WO2021139815A1 - 废气净化***及净化方法 - Google Patents

废气净化***及净化方法 Download PDF

Info

Publication number
WO2021139815A1
WO2021139815A1 PCT/CN2021/071121 CN2021071121W WO2021139815A1 WO 2021139815 A1 WO2021139815 A1 WO 2021139815A1 CN 2021071121 W CN2021071121 W CN 2021071121W WO 2021139815 A1 WO2021139815 A1 WO 2021139815A1
Authority
WO
WIPO (PCT)
Prior art keywords
exhaust gas
sheet
vapor
cooling device
droplets
Prior art date
Application number
PCT/CN2021/071121
Other languages
English (en)
French (fr)
Inventor
高境
赵传峰
李艳萍
杨宝勇
段承希
赵雯
高迪
Original Assignee
高境
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 高境 filed Critical 高境
Publication of WO2021139815A1 publication Critical patent/WO2021139815A1/zh

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/26—Drying gases or vapours
    • B01D53/265—Drying gases or vapours by refrigeration (condensation)
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/1431—Pretreatment by other processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/18—Absorbing units; Liquid distributors therefor

Definitions

  • the invention relates to the field of industrial waste gas and air purification, in particular to a method and system for removing gaseous pollutants in waste gas, especially gaseous pollutants in wet waste gas.
  • Gaseous pollutants are pollutants that exist in molecular state under normal conditions and atmospheric pressure.
  • Gaseous pollutants include gas pollutants and vapor pollutants.
  • Gas is a substance that exists as a gas at normal temperature and pressure.
  • Common gas pollutants include: CO, SO 2 , NO 2 , NH 3 , H 2 S, low boiling point organics (such as propane, butane, etc.).
  • Vapor is a gas that evaporates from a substance that is liquid or solid at room temperature, such as a gaseous substance formed by sublimation of a solid or volatilization of a liquid. Steam can only be obtained after high temperature conversion, and it is unstable at room temperature. It can be seen that as the operating temperature changes, the scope of steam and gas will change.
  • butane has a boiling point of 0.50°C, and at 20°C, it is a gas; but at -20°C, butane is liquid, and butane in the air is steam.
  • Common vapor pollutants include: volatile organic compounds (VOCs for short), volatile heavy metals (such as mercury, arsenic, selenium vapor), SO 3 vapor and so on. When the vapor is cold, it can gradually return to its original solid or liquid state.
  • Gaseous pollutants can be divided into primary pollutants and secondary pollutants.
  • Primary pollutants refer to the original pollutants discharged directly from the pollution source into the atmosphere; secondary pollutants refer to a series of chemical or photochemical reactions between primary pollutants and existing components in the atmosphere, or several primary pollutants And new pollutants with different properties from the primary pollutants are generated.
  • the primary pollutants that have received widespread attention in air pollution control include sulfur oxides, nitrogen oxides, carbon oxides, and organic compounds; secondary pollutants include sulfuric acid smog and photochemical smog.
  • gaseous pollutants that are easily soluble in water such as SO 2 , NH 3, etc.
  • they can be absorbed into the water body through water spray to achieve removal from the exhaust gas; but for gaseous pollutants that are difficult to dissolve in water ,
  • gaseous pollutants that are difficult to dissolve in water Such as butane, when spraying with conventional water, it is difficult to dissolve in water and has poor absorption effect and is difficult to remove. It needs to be removed by combustion decomposition or activated carbon adsorption.
  • Activated carbon is difficult to adsorb butane because it preferentially adsorbs water vapor, and it is difficult to achieve a good removal effect.
  • Vapor pollutants such as SO 3 vapor
  • SO 3 vapor can absorb moisture and transform into aerosol particles when sprayed with water, and have a small particle size (about 50 nanometers), which is difficult to be caught by the sprayed water droplets and the removal efficiency is also low.
  • the purpose of the present invention is to provide a purification system and purification method that can effectively remove gaseous pollutants and/or recover gaseous pollutants in exhaust gas.
  • the method of the present invention is particularly suitable for removing and/or recovering insoluble gaseous pollutants in high-humidity exhaust gas. And/or purification system and purification method of vapor pollutants.
  • One aspect of the present invention provides a method for removing gaseous pollutants in exhaust gas, including: passing the exhaust gas through a gaseous pollutant removal device, the gaseous pollutant removal device comprising an airflow channel and a cooling device arranged in the airflow channel, the cooling device It includes at least two sheet-shaped members, the sheet-shaped members are substantially parallel to each other and substantially parallel to the flow direction of the exhaust gas, the exhaust gas passes between adjacent sheet-shaped members, and the exhaust gas flow rate is not higher than 10m/s; the sheet-shaped member
  • the temperature of the outer surface is lower than the dew point temperature of at least part of the vapor components in the exhaust gas. At least part of the vapor in the exhaust gas is condensed into droplets by cooling the exhaust gas.
  • the gaseous pollutants in the exhaust gas are adsorbed on the droplets and follow the liquid. The wet drop settles on the outer surface of the sheet-like member.
  • the method further includes: recovering the droplets wet-sedimented to the outer surface of the sheet-like member.
  • the flow rate of the exhaust gas is not higher than 9m/s, or not higher than 8m/s, or not higher than 7m/s, or not higher than 6m/s, or not higher than 5m/s, Or not higher than 4m/s, or not higher than 3m/s, or not higher than 2m/s, or not higher than 1m/s.
  • the flow rate includes the flow rate of the exhaust gas in the gas flow channel.
  • the ratio of the distance between adjacent sheet-like members to the length of the sheet-like member in the air flow direction is less than 0.5, less than 0.2, less than 0.1, or less than 0.05.
  • the relative humidity of the exhaust gas is greater than or equal to 60%, greater than or equal to 80%, or greater than or equal to 90%.
  • the cooling device is a plate heat exchanger.
  • the cooling device is a finned tube heat exchanger, and fins on the heat exchanger constitute the sheet-shaped member.
  • the finned tube heat exchanger is a finned heat tube heat exchanger.
  • the cooling device is made of a metal material.
  • the metal components made of steel, copper, or aluminum in the cooling device are sprayed or passivated with anticorrosive materials.
  • the sheet member is a semiconductor thermoelectric chip
  • the cooling device includes two semiconductor thermoelectric chips with opposite cold ends, and exhaust gas passes between the cold ends of the two semiconductor thermoelectric chips.
  • the exhaust gas is pretreated before or when the exhaust gas is passed through the cooling device.
  • the pretreatment includes increasing the vapor content in the exhaust gas, adding acidic substances to the exhaust gas, oxidizing the exhaust gas, and adding to the exhaust gas. Any one or more of adding alkaline substances and pressurizing exhaust gas.
  • the increasing the vapor content in the exhaust gas includes spraying a substance that can form vapor in the exhaust gas into the exhaust gas.
  • the temperature of these substances preferably drops below their dew point temperature during the cooling process of the exhaust gas, so that liquid droplets can be formed.
  • these substances are water, ethanol, ethylene glycol, other substances that may be present in the exhaust gas in a vapor state (for example, organic substances), or solutions containing any of them, or vapors of these substances.
  • the acidic substance is an acidic substance that can be combined with water vapor in the exhaust gas to form an acid mist with a high dew point temperature, such as one or more of SO 3 , HCl, and/or acetic acid.
  • the alkaline substance can react with some gaseous pollutants to produce a substance with a higher boiling point and/or more soluble in water, such as ammonia gas NH 3 , sodium carbonate, quicklime CaO, or sodium hydroxide Or one or more of sodium hydroxide solution.
  • some gaseous pollutants such as ammonia gas NH 3 , sodium carbonate, quicklime CaO, or sodium hydroxide Or one or more of sodium hydroxide solution.
  • the oxidation treatment includes adding oxidizing substances to the exhaust gas and/or passing the exhaust gas through a photocatalytic oxidation device.
  • the oxidizing substance can oxidize some gaseous pollutants into substances with higher boiling points and/or more soluble in droplets, such as one or more of ozone and sodium chlorite.
  • the method further includes spraying any one or a mixture of water, an aqueous solution, and an organic solvent on the outer surface of the sheet-shaped member.
  • the gaseous pollutant removal device includes a set of cooling devices arranged side by side on the cross section of the exhaust gas flow direction.
  • the gaseous pollutant removal device includes multiple sets of cooling devices arranged along the flow direction of the exhaust gas, and each set of cooling devices is arranged side by side on a cross section of the flow direction of the exhaust gas.
  • the adjacent two sets of cooling devices are arranged in a staggered or in-line arrangement.
  • other particulate matter trapping devices are used to further remove large-diameter droplet particulate matter.
  • the other particulate matter trapping device is a mist eliminator or dust collector.
  • the method further includes dripping or running away the wet droplets that have settled on the outer surface of the sheet member. In some embodiments, droplets that drip or run off are recovered.
  • Another aspect of the present invention provides a system for removing gaseous pollutants in exhaust gas, including: a gaseous pollutant removal device for exhaust gas to pass and be processed, the gaseous pollutant removal device including an airflow channel and a cooling device arranged in the airflow channel
  • the cooling device includes at least two sheet-like members, and the sheet-like members are substantially parallel to each other and substantially parallel to the direction of the airflow.
  • the ratio of the distance between adjacent sheet-like members to the length of the sheet-like member in the air flow direction is less than 0.5, less than 0.2, less than 0.1, or less than 0.05.
  • the cooling device is a plate heat exchanger.
  • the cooling device is a finned tube heat exchanger, and fins on the heat exchanger constitute the sheet-shaped member.
  • the finned tube heat exchanger is a finned heat tube heat exchanger.
  • the cooling device is made of a metal material.
  • the metal components made of steel, copper, or aluminum in the cooling device are sprayed or passivated with anticorrosive materials.
  • the sheet member is a semiconductor thermoelectric sheet
  • the cooling device includes two semiconductor thermoelectric sheets with opposite cold ends.
  • an injection device is provided on the upstream side of the cooling device for injecting any one of substances that can form vapor in the exhaust gas, oxidizing substances, acidic substances, and alkaline substances into the exhaust gas.
  • substances that can form vapor in the exhaust gas oxidizing substances, acidic substances, and alkaline substances into the exhaust gas.
  • oxidizing substances oxidizing substances, acidic substances, and alkaline substances into the exhaust gas.
  • an oxidation device is provided on the upstream side of the cooling device for oxidizing the exhaust gas.
  • the oxidation device is a photocatalytic oxidation device.
  • a pressurizing device is provided on the upstream side of the cooling device for pressurizing the exhaust gas.
  • a spray device is provided on one or both sides of the gaseous pollutant removal device for spraying one of water, an aqueous solution, or an organic solvent on the outer surface of the sheet-shaped member. A mixture of several.
  • the gaseous pollutant removal device includes a set of cooling devices arranged side by side on the cross section of the air flow channel.
  • the gaseous pollutant removal device includes multiple sets of cooling devices arranged along the direction of the airflow channel, and each set of cooling devices is arranged side by side on a cross section of the airflow channel.
  • the adjacent two sets of cooling devices are arranged in a staggered or in-line arrangement.
  • other particulate trapping devices are provided after the cooling device.
  • the other particulate matter trapping device is a mist eliminator or dust collector.
  • the system further includes a drainage channel for drawing and/or recovering droplets through the drainage channel.
  • the present invention uses a gaseous pollutant removal device to treat exhaust gas, and its structure is conducive to condensing vapor to form liquid droplets, and efficiently adsorbs gaseous pollutants by means of the high specific surface area of the liquid droplets; further adopts metal sheet-shaped members, which have strong thermal conductivity, and when used as a cooler , It can form a large temperature gradient between the surface of the sheet-shaped component and the exhaust gas, and use the thermophoretic force to push the liquid droplets adsorbing gaseous pollutants to the surface of the sheet-shaped component; the droplets wet-sink on the outer surface of the sheet-shaped component and gather to a certain extent. After the measurement, the gaseous pollutants are removed from the exhaust gas.
  • the present invention relates to the following solutions:
  • a method for removing gaseous pollutants in exhaust gas comprising: passing the exhaust gas through a gaseous pollutant removal device, the gaseous pollutant removal device comprising an airflow channel and a cooling device arranged in the airflow channel, the cooling device comprising at least Two sheet-shaped members, the sheet-shaped members are substantially parallel to each other and substantially parallel to the flow direction of the exhaust gas, the exhaust gas passes between adjacent sheet-shaped members, and the exhaust gas flow rate is not higher than 10m/s; the outer surface of the sheet-shaped member The temperature is lower than the dew point temperature of at least part of the vapor components in the exhaust gas. At least part of the vapor in the exhaust gas is condensed into droplets by cooling the exhaust gas. The gaseous pollutants in the exhaust gas are adsorbed on the droplets and wet with the droplets. Settle on the outer surface of the sheet-shaped member.
  • Scheme 2 The method according to scheme 1, further comprising: recovering liquid droplets wet-sedimented on the outer surface of the sheet-like member.
  • Scheme 3 The method according to scheme 1 or 2, wherein the flow rate of the exhaust gas is not higher than 5 m/s.
  • Solution 4 The method according to any one of the aspects 1 to 3, wherein the ratio of the distance between adjacent sheet-like members to the length of the sheet-like members in the air flow direction is less than 0.5.
  • Option 5 The method according to any one of options 1-4, wherein the relative humidity of the exhaust gas is greater than or equal to 60%.
  • Item 7 The method according to any one of items 1 to 5, wherein the cooling device is a finned tube heat exchanger, and fins on the heat exchanger constitute the sheet-shaped member.
  • Item 8 The method according to item 7, wherein the finned tube heat exchanger is a finned heat tube heat exchanger.
  • Solution 9 The method according to any one of the solutions 6-8, wherein the cooling device is made of a metal material.
  • Solution 10 The method according to claim 9, wherein the metal components made of steel, copper, and aluminum in the cooling device are sprayed or passivated with anticorrosive materials.
  • Item 11 The method according to any one of items 1-5, wherein the sheet-shaped member is a semiconductor thermoelectric chip, the cooling device includes two semiconductor thermoelectric chips with opposite cold ends, and the exhaust gas flows from the cold ends of the two semiconductor thermoelectric chips. Pass between.
  • Option 12 The method according to any one of options 1-11, wherein the exhaust gas is pretreated before passing the exhaust gas through a cooling device, the pretreatment includes increasing the vapor content in the exhaust gas, adding acidic substances to the exhaust gas, and performing treatment on the exhaust gas. Any one or more of oxidation treatment, addition of alkaline substances to exhaust gas, and pressurization of exhaust gas.
  • Item 13 The method according to item 12, wherein the increasing the vapor content in the exhaust gas includes spraying into the exhaust gas a substance that can form vapor in the exhaust gas.
  • Item 14 The method according to item 12, wherein the oxidation treatment includes adding an oxidizing substance to the exhaust gas and/or passing the exhaust gas through a photocatalytic oxidation device.
  • Solution 15 The method according to any one of the aspects 1-14, further comprising spraying any one or a mixture of any one or more of water, an aqueous solution, and an organic solvent onto the outer surface of the sheet-shaped member.
  • Item 16 The method according to any one of items 1-15, wherein the gaseous pollutant removal device includes a set of cooling devices arranged side by side on a cross section of the flow direction of the exhaust gas.
  • Item 17 The method according to any one of items 1-16, wherein the gaseous pollutant removal device includes multiple sets of cooling devices arranged along the flow direction of the exhaust gas, and each set of cooling devices is arranged side by side on a cross section of the flow direction of the exhaust gas .
  • Item 18 The method according to item 17, wherein the adjacent two sets of cooling devices are arranged in a staggered arrangement or arranged in a row.
  • Item 19 The method according to any one of items 1-18, wherein after the exhaust gas passes through the cooling device, another particle trap device is used to further remove large-diameter droplet particles.
  • Item 20 The method according to Item 19, wherein the other particulate matter trapping device is a mist eliminator or a dust eliminator.
  • Item 21 The method according to items 1-19, wherein the method further comprises dripping or running away the liquid droplets that are wet settled on the outer surface of the sheet-shaped member.
  • Item 22 The method according to item 21, wherein the droplets that wet settled on the outer surface of the sheet-like member are flowed away by spraying the droplets wet-settled on the outer surface of the sheet-like member to wash off the outer surface of the sheet-like member, and then pass The drainage channel makes it flow away.
  • a system for removing gaseous pollutants in exhaust gas comprising: a gaseous pollutant removal device for exhaust gas to pass and be processed, the gaseous pollutant removal device including an airflow channel and a cooling device arranged in the airflow channel, the cooling The device includes at least two sheet-like members which are substantially parallel to each other and substantially parallel to the direction of the airflow.
  • Item 24 The system according to item 23, wherein the ratio of the distance between adjacent sheet-like members to the length of the sheet-like members in the air flow direction is less than 0.5.
  • Item 25 The system according to item 23 or 24, wherein the cooling device is a plate heat exchanger.
  • Item 26 The system according to Item 23 or 24, wherein the cooling device is a finned tube heat exchanger, and fins on the heat exchanger constitute the sheet-shaped member.
  • Item 27 The system according to item 26, wherein the finned tube heat exchanger is a finned heat tube heat exchanger.
  • Item 28 The system according to any one of items 23-27, wherein the cooling device is made of a metal material.
  • Item 29 The system according to item 28, wherein the metal components made of steel, copper, or aluminum in the cooling device are sprayed or passivated with anticorrosive materials.
  • Item 30 The system according to item 23, wherein the sheet-shaped member is a semiconductor thermoelectric sheet, and the cooling device includes two semiconductor thermoelectric sheets with opposite cold ends.
  • Item 31 The system according to any one of items 23-30, wherein an injection device is provided on the upstream side of the cooling device for injecting substances that can form vapor in the exhaust gas, oxidizing substances, and acidic substances into the exhaust gas. Any one or more of substances and alkaline substances.
  • Item 32 The system according to any one of items 23 to 31, wherein an oxidation device is provided on the upstream side of the cooling device for oxidizing the exhaust gas.
  • Item 33 The system according to item 31, wherein the oxidation device is a photocatalytic oxidation device.
  • Item 34 The system according to any one of items 23 to 33, wherein a pressurizing device is provided on the upstream side of the cooling device for pressurizing the exhaust gas.
  • Item 35 The system according to any one of items 23 to 34, wherein a spray device is provided on one or both sides of the gaseous pollutant removal device for spraying water on the outer surface of the sheet-shaped member, One or a mixture of several in aqueous solution and organic solvent.
  • Item 36 The system according to any one of items 23 to 35, wherein the gaseous pollutant removal device includes a set of cooling devices arranged side by side on the cross section of the air flow channel.
  • Item 37 The system according to any one of items 23-35, wherein the gaseous pollutant removal device includes multiple sets of cooling devices arranged along the direction of the airflow channel, and each set of cooling devices is arranged in parallel on a cross-section of the airflow channel .
  • Item 38 The system according to item 37, wherein the adjacent two sets of cooling devices are arranged in a staggered arrangement or arranged in a row.
  • Item 39 The system according to any one of items 23 to 38, wherein after the cooling device, another particulate matter trapping device is provided.
  • Item 40 The system according to Item 39, wherein the other particulate matter trapping device is a mist eliminator or a dust eliminator.
  • Solution 41 The system according to any one of the solutions 23-40, further comprising a drainage channel for drawing and/or recovering liquid droplets through the drainage channel.
  • Item 42 The system of item 26, wherein the finned tube heat exchanger is an inner finned tube heat exchanger.
  • Figure 1 is a schematic diagram of a gaseous pollutant removal device.
  • Fig. 2 is a schematic structural diagram of an embodiment of a gaseous pollutant removal device.
  • Figure 3 is a schematic diagram of the arrangement of a set of cooling devices.
  • Figure 4 is a schematic diagram of the arrangement of multiple sets of cooling devices.
  • Figure 5 is a schematic diagram of the structure of a finned tube heat exchanger.
  • Fig. 6 is a schematic diagram of another embodiment of a gaseous pollutant removal device.
  • Fig. 7 is a schematic diagram of another embodiment of a gaseous pollutant removal device.
  • Fig. 8 is a schematic diagram of another embodiment of a gaseous pollutant removal device.
  • Fig. 9 is a schematic diagram of another embodiment of a gaseous pollutant removal device.
  • Fig. 10 is a schematic cross-sectional view of the airflow channel of the petal-shaped tube heat exchanger.
  • gaseous pollutants refer to pollutants existing in the form of molecules in the exhaust gas.
  • Gaseous pollutants include gaseous pollutants and/or vapor pollutants.
  • the gaseous pollutants described herein are pollutants that are present in the exhaust gas in gaseous form.
  • the boiling point of gaseous pollutants is lower than the temperature of the exhaust gas, and therefore exists as a gas.
  • Gas pollutants include, but are not limited to, any of CO, SO 2 , NO, NH 3 , H 2 S, low boiling point organics (such as low boiling point alkanes, such as propane, butane, isobutane, neopentane, etc.) Or several.
  • Some volatile organic compounds (VOCs for short) can also exist in the exhaust gas in the form of gas, constituting gaseous pollutants. For those skilled in the art, it is possible to judge whether a certain gas component in the exhaust gas is a gas pollutant according to common sense, and it can be easily judged according to the type of the gas component, the boiling point, and the temperature of the exhaust gas.
  • the vapor pollutants described herein refer to pollutants that exist in the form of vapor in the exhaust gas.
  • the boiling point of vapor pollutants is higher than the temperature of the exhaust gas, but the dew point is lower than the temperature of the exhaust gas, so it exists in the form of vapor in the exhaust gas.
  • Vapor pollutants include but are not limited to some volatile organic compounds (such as isopentane, benzene, acetic acid, furfural, etc.), volatile heavy metals (such as mercury, arsenic, selenium vapor), SO 3 vapor (also known as sulfuric acid vapor) ) Any one or more of the following.
  • volatile organic compounds such as isopentane, benzene, acetic acid, furfural, etc.
  • volatile heavy metals such as mercury, arsenic, selenium vapor
  • SO 3 vapor also known as sulfuric acid vapor
  • the gas molecules (adsorbent) move to the surface of the droplet (adsorbent), the gas molecules stay on the surface of the droplet due to the interaction between the gas molecules and the molecules on the surface of the droplet. This phenomenon is called gas molecules in the liquid. Adsorption on the surface of the drop. If gas molecules (adsorbents) further enter the inside of the droplet to form a solution, this process is called absorption.
  • the adsorption capacity of a droplet (adsorbent) is mainly positively related to its surface free energy and specific surface area. The surface free energy of water in common liquids is the largest; the specific surface area of a droplet is usually inversely proportional to its particle size.
  • nano-micron droplets such as mist droplets, Its particle size is usually on the order of microns
  • Atmospheric environmental scientific research found that fog has a good adsorption effect on gaseous pollutants, even hydrophobic (hardly soluble in water) gaseous pollutants.
  • the content of hydrophobic organic compounds in fog droplets is higher than that in raindrops (the particle size is usually The content in millimeter level) is ten to thousands times higher.
  • the inventor found that a large number of small particle size droplets can be obtained by cooling the exhaust gas. These small particle size droplets can further adsorb and/or absorb other gaseous pollutants in the exhaust gas through thermophoresis. These liquid droplets realize wet sedimentation, and then aggregate to form larger liquid beads or liquid film and remove them, which can effectively remove gaseous pollutants in the exhaust gas.
  • the liquid droplets or liquid film containing the gaseous pollutants can be collected and recycled to reuse the gaseous pollutant components.
  • the main components of oil and gas pollutants, tar pollutants, etc. are organic mixtures, which can be added to gasoline or other oils for reuse after being recovered.
  • the exhaust gas containing steam can form liquid droplets when the temperature is cooled down, so that the temperature of the exhaust gas is cooled to the dew point or below the dew point of the contained vapor. Because these vapors undergo a phase change at the dew point temperature, liquid droplets can be formed. Under the condition that the vapor has a higher degree of supersaturation, small-sized droplets can be formed, and the particle size of the small-sized droplets can be on the order of nanometers and micrometers. In the present invention, the formed droplets of nanometers The small particle size droplets can also be called mist droplets.
  • substance A refers to one or more substances in the exhaust gas.
  • substance B For substances that exist in the vapor state, the temperature of substance A drops to its own dew point or below during the cooling process of the exhaust gas, thereby forming a large number of droplets.
  • These droplets formed by substance A further adsorb and/or absorb substance B, and further aggregate into larger liquid beads or liquid film after wet sedimentation, and then be removed.
  • Substance A can contain some vapor pollutants, water vapor and/or any other substances that can exist in the exhaust gas in a vapor state (such as alcohol).
  • Substance B refers to vapor pollutants in addition to other vapor pollutants and other vapor pollutants that exist as substance A. /Or gaseous pollutants.
  • To determine which substances in the exhaust gas belong to substance A and which substances belong to substance B it needs to be determined according to the boiling point temperature, dew point temperature, and target cooling temperature of each substance. In short, the steam whose dew point temperature is higher than the target cooling temperature belongs to substance A. Vapors and gases whose dew point temperature is lower than the target cooling temperature are B substances.
  • a part of the gaseous pollutants in the exhaust gas is contained in the A substance, and a part is contained in the B substance.
  • substance A contains water vapor and some vapor pollutants
  • substance B contains gas pollutants and some vapor pollutants.
  • the exhaust gas can be pretreated by the following two ways: 1. Increase the amount of substance A, such as adding water vapor or other substances (such as alcohol) that can exist in the exhaust gas in a vapor state to the exhaust gas. Increase the vapor content in the exhaust gas, or add acidic substances to the exhaust gas to introduce acid mist, or pressurize the exhaust gas to increase the partial pressure (relative humidity) of substance A; 2. Modify substance B to make substance B easier
  • the droplets formed by substance A are absorbed and/or adsorbed, such as oxidizing the exhaust gas and/or adding alkaline substances to the exhaust gas. This modification, for example, can transform at least part of the substance B into a higher boiling point through a chemical reaction Substances and/or substances with higher solubility in the droplets.
  • Dew point temperature refers to the temperature at which a certain gas (vapor) content and pressure do not change when the gas is cooled to saturation.
  • the dew point temperature can be checked according to the saturated vapor partial pressure diagram of the gas at different temperatures. Taking water as an example, the dew point temperature of water is the saturation temperature corresponding to the partial pressure of water vapor. For the water vapor contained in the air, the dew point temperature is the temperature at which it turns into dew.
  • the dew point temperature of water vapor can be referred to as the water dew point temperature
  • the dew point temperature at which the acid gas combines with water vapor in the exhaust gas to form an acid mist can be referred to as the acid dew point temperature.
  • the dew point temperature can refer to the dew point temperature of any steam present in the exhaust gas, and can refer to either the water dew point temperature or the steam dew point temperature, or the acid dew point temperature.
  • the vapor may also be referred to as a vapor-like substance.
  • a vapor-like substance refers to a substance that has a boiling point higher than the temperature of the exhaust gas but a dew point lower than the temperature of the exhaust gas, and exists in a vapor state in the exhaust gas.
  • the exhaust gas may contain one or more kinds of steam, and the steam may be water vapor, any vapor pollutant and/or any other substances that can exist in the exhaust gas as a vapor state (for example, ethanol, SO 3 , Hg, etc.), Therefore, the exhaust gas may contain water vapor, one or more vapor pollutants and/or any other substances that can exist in the exhaust gas in a vapor state (such as ethanol vapor, SO 3 vapor, Hg vapor, etc.), or their mixture.
  • the steam may be water vapor, any vapor pollutant and/or any other substances that can exist in the exhaust gas as a vapor state (for example, ethanol, SO 3 , Hg, etc.), Therefore, the exhaust gas may contain water vapor, one or more vapor pollutants and/or any other substances that can exist in the exhaust gas in a vapor state (such as ethanol vapor, SO 3 vapor, Hg vapor, etc.), or their mixture.
  • Liquid droplets are formed by cooling the vapor in the exhaust gas.
  • Different types of steam contained in the exhaust gas have different dew point temperatures.
  • the steam with a higher dew point first forms droplets.
  • the vapor used to form liquid droplets may be water vapor contained in the exhaust gas, any vapor pollutant, and/or any other substance that may exist in the exhaust gas in a vapor state (for example, ethanol), and is not limited to water vapor. It should be understood that the exhaust gas does not have to contain water vapor, it is sufficient if it contains vapor (any vapor-like substance).
  • the content of vapor in the exhaust gas is not particularly limited, as long as small-diameter droplets can be formed when the exhaust gas is cooled down. It should be understood that the more vapor contained in the exhaust gas, the more liquid droplets formed during cooling, and the more other gaseous pollutants adsorbed and/or absorbed, and the better the removal effect.
  • high-humidity waste gas is preferred, for example, waste gas with relative humidity greater than or equal to 60%, humidity greater than or equal to 80%, or humidity greater than or equal to 90%.
  • the exhaust gas can be pretreated to increase the vapor content in the exhaust gas. For example, substances that can form vapor in the exhaust gas are added to the exhaust gas.
  • These substances are preferably lowered to their dew point during the cooling process of the exhaust gas.
  • droplets can be formed.
  • These substances can be, for example, water, ethanol, ethylene glycol, other substances that can exist in the exhaust gas in a vapor state (for example, organic substances), or a solution containing any of them, or vapors of these substances.
  • these substances can be sprayed into the exhaust gas to increase the vapor content in the exhaust gas.
  • the relative humidity of the exhaust gas can reach 60% or more, 80% or more, or 90% or more.
  • the composition of the formed droplets varies with the type of vapor in the exhaust gas, the dew point temperature of the vapor, the temperature of the exhaust gas, and the cooling temperature. It can include water droplets, droplets formed after the temperature of vapor pollutants are cooled, droplets of vapor pollutants in aqueous solution, and vapor One or more of the pollutant ethanol solution droplets.
  • the pretreatment may also include pressurizing the exhaust gas to increase the partial pressure of the vapor contained therein. After pressurization, the partial pressure of each component in the exhaust gas is increased in equal proportion. After the partial pressure of the original unsaturated vapor component increases, a part of it can reach supersaturation and condense into droplets. Even if the other vapor components are not supersaturated, their components Higher pressures are also easier to condense into droplets through a small drop in temperature.
  • the exhaust gas can be pressurized by a pressurizing device, and then passed through a gaseous pollutant removal device.
  • the pressurizing device may be, for example, an air compressor to isothermally pressurize the exhaust gas.
  • the air pressure of the exhaust gas may be increased from a normal 1 atmosphere to 2 atmospheres or more, 3 atmospheres or more, or 4 atmospheres or more. Or greater than or equal to 5 atmospheres, etc.
  • acid gas such as SO 3 , HCl, acetic acid, etc.
  • acid mist When there is acid gas (such as SO 3 , HCl, acetic acid, etc.) in the exhaust gas, it will combine with the water vapor in the exhaust gas, and the formed substance is called acid mist.
  • the condensation temperature of acid mist is called acid dew point, which is higher than water.
  • the dew point is much higher. Taking SO 3 as an example, the higher its concentration, the higher the acid dew point, and the acid dew point in the exhaust gas can reach 140-160°C, or even higher.
  • the SO 3 acid dew point can be calculated according to the following formula:
  • the pretreatment of the exhaust gas may also include adding an acidic substance that can combine with water vapor in the exhaust gas to form an acid mist with a high dew point temperature to the exhaust gas containing water vapor (such as high-humidity exhaust gas), thereby improving Quickly form small-size droplets, and form more small-size droplets, improving the removal efficiency of gaseous pollutants.
  • water vapor and the above-mentioned acidic substance can also be added to the exhaust gas at the same time.
  • the above-mentioned acidic substance may be sprayed into the exhaust gas containing water vapor.
  • the droplets formed by the cooling of the vapor in the exhaust gas will further adsorb other gaseous pollutants. If the gas adsorbed on the surface of the adsorbent is only one molecule thick, it is called monolayer adsorption; if the adsorption layer is thicker than one molecule, it is called multi-molecular layer adsorption. When the temperature of the adsorbate is lower than its normal boiling point, multi-molecular layer adsorption often occurs, so the higher the boiling point of the gaseous pollutant, the easier it is to be adsorbed.
  • the liquid droplets can further absorb the adsorbed gaseous pollutants, and the degree of absorption is related to the diffusion rate of the gaseous pollutant molecules, the solubility of the gaseous pollutants in the droplets (such as water droplets), and the reactivity in the droplets (such as aqueous solutions).
  • the higher the solubility of gaseous pollutants in droplets the higher the degree of absorption of such gaseous pollutants by the droplets, the higher the degree of absorption of such gaseous pollutants by the droplets.
  • the adsorbed gaseous pollutants may be those gaseous pollutants that have not yet reached their dew point temperature during the cooling process of the exhaust gas, and may include vapor pollutants and/or gaseous pollutants that have not yet reached their dew point temperature. .
  • the pretreatment of the exhaust gas may also include converting the gaseous pollutants contained in the exhaust gas into gaseous substances with higher boiling points (gaseous substances with higher boiling points). It is easier to adsorb onto droplets), or convert the gaseous pollutants contained in the exhaust gas into more soluble droplets (for example, when the droplet is composed of water or an aqueous solution, it is more soluble in water), that is, in the droplet
  • these transformations can be achieved, for example, through chemical reactions.
  • oxidizing substances and/or alkaline substances may be added (for example, sprayed) to the exhaust gas.
  • the oxidizing substances can oxidize some gaseous pollutants into substances with higher boiling points and/or more soluble in liquid droplets.
  • the choice of oxidizing substances depends on the gaseous pollutants in the exhaust gas, such as adding ozone O 3 and subchlorine.
  • Sodium NaClO 2 can oxidize NO to NO 2 , and those skilled in the art can determine the oxidizing substance used according to the composition of gaseous pollutants and general physical and chemical knowledge.
  • Non-limiting examples of the oxidizing substance include one or more of ozone and sodium chlorite.
  • oxidizing substances such as ozone and sodium chlorite can be sprayed into the exhaust gas to oxidize the NO in the exhaust gas to NO 2 and N 2 O 5 , which have a higher boiling point and are more soluble in water. In order to be better absorbed and/or absorbed by the droplets.
  • ozone can be sprayed into the exhaust gas to oxidize furfural with a boiling point of 167 degrees to furoic acid with a boiling point of 232 degrees. Capture.
  • the alkaline substance may react with part of the gaseous pollutants (for example, together with the gaseous pollutants, it is adsorbed by the droplets and further reacted) to produce a substance with a higher boiling point and/or more soluble in water.
  • alkaline substances can be added to the exhaust gas to make it absorb some acid gaseous pollutants.
  • the alkaline substance include ammonia gas NH 3 , sodium carbonate, quicklime CaO, or sodium hydroxide or sodium hydroxide solution, and the like.
  • ammonia gas can be sprayed into the exhaust gas.
  • the ammonia gas is adsorbed by the droplets and reacts with NO 2 , N 2 O 5 and other substances in the droplets, thereby causing the droplets to adsorb and/or absorb
  • the NO 2 and N 2 O 5 are more.
  • the exhaust gas may also be oxidized in other ways, such as passing the exhaust gas through a photocatalytic oxidation device, etc., to oxidize some gaseous pollutants into substances with higher boiling points and/or more soluble in liquid droplets.
  • Cooling the exhaust gas can be achieved by using a cooling device (such as a heat exchanger), which can make the temperature of the outer surface of the cooling device (that is, the surface of the cooling device in contact with the exhaust gas) (also referred to as the target cooling temperature in the present invention) lower than that of the exhaust gas
  • a cooling device such as a heat exchanger
  • the dew point temperature of at least a part of the vapor in the air (this part of the vapor may also be referred to as substance A), so that the at least a part of the vapor forms droplets during the cooling process.
  • Means for maintaining a certain temperature on the outer surface of the cooling device are well known to those skilled in the art, for example, cooling liquid or cooling gas or any other suitable cold source can be used.
  • the temperature of the outer surface of the cooling device can be determined according to the type, content, dew point temperature, etc. of the steam contained in the exhaust gas, and it can be lower than the dew point of at least one, at least two, at least three or more kinds of steam contained in the exhaust gas.
  • the temperature should be at least lower than the highest dew point temperature in the exhaust gas.
  • the highest dew point temperature in the exhaust gas refers to the temperature at which condensate droplets begin to appear during the cooling process of the exhaust gas under other conditions unchanged. It can also be understood as Among the different components contained in the exhaust gas, the dew point temperature of the component with the highest dew point temperature.
  • the different components mentioned here refer to the components with the dew point temperature, such as acid mist, water vapor, or other vapor components.
  • the temperature of the outer surface of the cooling device can be lower than the acid dew point temperature of the exhaust gas, that is, the dew point temperature of the acid mist contained in the exhaust gas. If there are multiple acid mists in the exhaust gas, there will be more acid mists.
  • An acid dew point temperature at this time, the temperature of the outer surface of the cooling device can be lower than any one or more kinds of acid dew point temperature, for example, lower than the highest acid dew point temperature.
  • the moisture content is 10%
  • the volume concentration of SO 3 is 10 ppm
  • the other has 5 ppm of insoluble organic vapor.
  • the size of the droplets formed in the cooling process of the exhaust gas is related to the supersaturation of the vapor that can form droplets after cooling.
  • the phase change process from water vapor to liquid water is called nucleation process.
  • nucleation process the phase change process from water vapor to liquid water
  • multiple water vapor molecules can form molecular clusters (or germs).
  • the formation of germ can be regarded as the random condensation of water vapor molecules. Whether it can continue to exist stably depends on the size of the embryo droplet and the degree of water vapor supersaturation in the exhaust gas.
  • the boundary layer is the thin fluid layer formed on the solid wall when the fluid flows through the solid wall, also known as the flow boundary layer and the attached surface layer. It is generally believed that temperature gradients and flow velocity gradients mainly exist in the boundary layer, and the fluid flow above the boundary layer can be regarded as the same temperature and the same flow velocity.
  • the calculation formula of the boundary layer thickness is:
  • ⁇ is the thickness of the boundary layer
  • L is the characteristic length
  • Re is the Reynolds number. The smaller the Reynolds number, the greater the thickness of the boundary layer.
  • Reynolds number is the dimensionless ratio of the inertial force and the viscous force of a fluid under flow conditions. Reynolds number can characterize fluid flow characteristics (ie laminar flow or turbulent flow).
  • Reynolds number Re is:
  • ⁇ is the fluid density
  • v is the fluid flow rate
  • ⁇ is the fluid viscosity
  • L is the characteristic length
  • characteristic length is well known to those skilled in the art. For example, when gas flows through a circular pipe, the term “characteristic length” is the equivalent diameter of the pipe. When the fluid flows through the plate, the term “characteristic length” is the distance that flows backward from the end of the plate.
  • the exhaust gas flow rate is preferably less than or equal to 10m/s, more preferably less than or equal to 9m/s, more preferably less than or equal to 8m/s, more preferably less than or equal to 7m/s, more preferably less than or equal to 6m/s, more preferably less than It is equal to 5 m/s, more preferably 4 m/s or less, more preferably 3 m/s or less, more preferably 2 m/s or less, and more preferably 1 m/s or less.
  • the cooling device of the present invention uses a sheet-shaped member.
  • the cooling device includes at least two parallel sheet-like members, the sheet-like members are substantially parallel to each other and substantially parallel to the flow direction of the exhaust gas, and a channel is formed between adjacent sheet-like members to Allow exhaust gas to pass between the channels.
  • the temperature of the outer surface of the sheet-shaped member is lower than the dew point temperature of at least a part of the vapor in the exhaust gas.
  • the sheet-shaped member can provide a larger contact area with the exhaust gas, thereby providing a larger boundary layer area.
  • the length of the passage formed by the adjacent sheet-shaped members in the air flow direction is longer, for example, at least 30 mm, preferably at least 45 mm, more preferably at least 60 mm, and more preferably at least 90 mm, so that the air flow can stay through the sheet-shaped member. Time is long enough.
  • the spacing between the sheet-like members is small, such as 45mm or less, more preferably 30mm or less, more preferably 15mm or less, more preferably 10mm or less, and more preferably 5mm or less, so that the boundary layer is occupied by the cooling device The space occupied is relatively large.
  • the ratio of the distance between adjacent sheet-like members to the length of the sheet-like member in the air flow direction is less than 0.5, less than 0.2, less than 0.1, or less than 0.05.
  • the distance between adjacent sheet-like members may be the distance between the center lines of adjacent sheet-like members; it may also be the distance between adjacent outer surfaces of adjacent sheet-like members, such as the lower surface of the upper sheet-like member The distance between the upper surface of the lower sheet member (when the sheet members are placed next to each other), or the distance between the inner surface of the outer sheet member and the outer surface of the inner sheet member (when the sheet member is inside and outside When placed next to each other, the inside and outside refers to the observer, the side close to the observer is called the outside, and the side far away from the observer is called the inside).
  • a part of the vapor component When using a cooling device in the form of a sheet-like member, when the surface temperature of the sheet-like member is lower than the dew point temperature of at least a part of the vapor component, a part of the vapor component will condense on the wall of the cooling device, and the other part will condense in the boundary layer
  • the boundary layer can form a high degree of supersaturation of the vapor component (up to 200% or more)
  • the vapor component can be nucleated homogeneously, and the droplet size formed is smaller than 1 micron, or even only about 10 nanometers, the number concentration can reach 10 5 -10 7 /cm 3 , and the specific surface area is very high, so as to adsorb and/or absorb other gaseous pollutants that have not reached their dew point temperature.
  • Dry sedimentation also called gravity sedimentation, refers to the process in which particles are caught by gravity sedimentation and collide with the surface of interference. It is collectively referred to as dry deposition. Gravity sedimentation is only effective for particles with a diameter greater than 10 microns.
  • Wet deposition refers to the process in which the contaminants in the gas are condensed and nucleated and then removed from the gas. It is divided into two stages: in-cloud removal and under-cloud removal. Clearance under cloud refers to the process of inertial collision and Brownian diffusion of liquid droplets to capture particles in the gas and remove them from the gas. It is mainly effective for larger particles.
  • In-cloud removal means that fine particles act as condensation nuclei and condense and grow. Through Brownian motion, migration (including thermophoresis, vapor pressure gradient force, etc.) or inertial collision process, a large number of fine particles are removed from the gas, mainly for 1 Fine particles below micrometers are effective.
  • the term "wet sedimentation” used in the present invention refers to a process in which gaseous pollutants in the exhaust gas are condensed and nucleated, and then removed by inertial collision, Brownian motion and/or migration.
  • thermophoretic force used in the present invention refers to the formation of the temperature gradient between the outer surface of the cooling device and the airflow (caused by the temperature difference between the outer surface of the cooling device and the airflow) that pushes tiny particles (such as liquid droplets) toward The force of cold wall movement, the greater the temperature difference, the greater the temperature gradient, and the greater the thermophoretic force.
  • thermophoretic force When particles move in a fluid with a temperature gradient, because the molecules in the hot and cold regions have different momentums when they collide with them, they appear to be subjected to a force opposite to the temperature gradient (ie, thermophoretic force), causing the particles to produce the opposite of the temperature gradient.
  • the speed of movement and deposition on a low-temperature surface is called the thermophoretic effect. Since the temperature gradient exists in the boundary layer of the cold wall, the thermophoretic effect is a short-range effect, which only occurs in the boundary layer of the wall.
  • thermophoretic force see "Aerosol Mechanics", Science Press, 1960) is:
  • F is the thermophoretic force
  • Xa is the thermal conductivity of the gas
  • Xi is the thermal conductivity of the particles
  • ⁇ is the gas viscosity coefficient
  • R is the particle radius
  • ⁇ a is the temperature gradient
  • ⁇ is the gas density
  • T is the gas temperature. Since the temperature gradient exists in the boundary layer, with the same thickness of the boundary layer, the greater the temperature difference, the greater the temperature gradient.
  • the viscous drag force is the force formed on the particles (such as liquid droplets) in contact with the gas flow.
  • the size of the viscous drag force is proportional to the square of the flow velocity and proportional to the square of the particle diameter.
  • the formula for calculating viscous drag is:
  • F is the viscous drag force
  • ⁇ is the drag force coefficient
  • ⁇ R 2 -particle projected area ⁇ -gas density
  • U-gas flow rate ⁇ R 2 -particle projected area
  • thermophoretic force is proportional to the temperature gradient and proportional to the first power of the droplet diameter, while the viscous drag force is proportional to the square of the droplet diameter, so under the same conditions
  • the smaller the droplet diameter the greater the ratio of the thermophoretic force to the viscous drag force, and the more obvious the effect of using the thermophoretic force to achieve settlement.
  • the lower the airflow velocity the smaller the viscous drag force, and the more obvious the effect of using thermophoretic force to achieve settlement.
  • the principle of the vapor pressure gradient force is that when supersaturated vapor is condensed, it will cause a vapor pressure gradient between the airflow and the condensation wall, and form a flow of gas molecules toward the condensation wall, causing the gas to collide with the particles on the opposite sides of the molecule. Cause the particles to migrate, and the direction of their movement points to the condensation surface.
  • the vapor pressure gradient force is also a microscopic force, and the vapor pressure gradient mainly exists in the boundary layer of the cold wall. The calculation of the vapor pressure gradient force is more complicated.
  • the magnitude of the vapor pressure gradient is proportional to the vapor pressure gradient. The higher the vapor content of the exhaust gas that can be condensed into droplets, the smaller the thickness of the boundary layer, and the greater the vapor pressure gradient.
  • the vapor pressure gradient force can be superimposed with the thermophoretic force to jointly promote the wet sedimentation of the droplets on the outer surface of the cooling device.
  • the liquid droplets that wet settled on the outer surface of the cooling device can be aggregated into larger droplets, which can be naturally dropped or flowed away, thereby being removed, and the removal of gaseous pollutants is realized.
  • the droplets can be washed away from the outer surface of the sheet-like member by spraying to make them flow away.
  • these droplets can be allowed to flow away through the drainage channel.
  • the dripped or run-off droplets can be collected for recovery and reuse.
  • the dripping or running away droplets can be collected in a container.
  • the liquid droplets that flow away can also be collected by drainage through the drainage channel.
  • the gaseous pollutant removal device 1 of the present invention has an airflow channel for exhaust gas to pass through, and a cooling device 2 is provided in the airflow channel.
  • the cooling device includes at least two sheet-shaped members, and the sheet-shaped members are substantially parallel to each other. And basically parallel to the direction of the airflow.
  • the exhaust gas can pass through the gaseous pollutant removal device and pass between the adjacent sheet-shaped components, and control the exhaust gas flow rate not to be higher than 10m/s; and control the outer surface temperature of the sheet-shaped components to be lower than the exhaust gas
  • the dew point temperature of at least part of the vapor components in the exhaust gas has a temperature difference sufficient to cause at least part of the vapor in the exhaust gas to condense into liquid droplets.
  • the removal of gaseous pollutants can be achieved by removing the wet droplets deposited on the outer surface of the sheet-shaped member.
  • the liquid droplets that wet settled on the outer surface of the sheet-shaped member can be caused to drop or flow away, and the liquid droplets can be further caused to flow away through the drainage channel.
  • these droplets can be recovered to facilitate the reuse of certain gaseous pollutant components.
  • the droplets can be collected through the drainage channel, or the droplets can be further collected into the container, for example, the droplets can be drained into the container.
  • the gaseous pollutant removal device of the present invention can be placed on the gas flow path of the exhaust gas, so that the exhaust gas flows through the gaseous pollutant removal device.
  • the gaseous pollutant removal device can be inserted in the middle of the airflow channel.
  • the gaseous pollutant removal device can replace a part of the airflow channel, or the airflow can be made The channel is cut off from the middle and is respectively connected with the air inlet and the air outlet of the gaseous pollutant removal device.
  • the gaseous pollutant removal device of the present invention can also be applied to a non-enclosed exhaust gas flow, as long as the exhaust gas flows through the gaseous pollutant removal device.
  • the “sheet-shaped member” in the present invention refers to a substantially sheet-shaped member.
  • the outer surface of the member may have a certain curvature or angle. For example, it may be pressed to form a corrugated shape, as long as it is generally sheet-shaped as a whole.
  • the device of the present invention When the device of the present invention is used to remove gaseous pollutants in the exhaust gas, the device should be placed in a position such that the parallel member is substantially parallel to the direction of the airflow.
  • substantially parallel does not exclude the presence of arcs or relative angles on lines and/or planes that are parallel to each other. It is only required to form approximately the same distance between them.
  • “substantially "Upper parallel” includes a completely parallel state and a not completely parallel but substantially parallel state. In the not completely parallel but substantially parallel state, the desired effect can basically be obtained.
  • the term “substantially parallel” includes the state where the line and the plane or the plane and the plane are completely parallel, and the situation where they move from the completely parallel state by 0° to about 10°-30°, for example, they move from the completely parallel state. 0° to about 10°-20°.
  • the sheet-like members can be connected to each other by any means that can fix them in a substantially parallel state, for example, they can be connected to each other at the edges of the sheet-like members by connecting pieces, or they can be connected to each other on the plate surface of the sheet-like members.
  • the positions are connected to each other by connecting pieces, and the connecting pieces may be plate-shaped, strip-shaped, tubular, column-shaped or any shape suitable for connecting sheet-shaped members.
  • the connecting piece should not block the direction of the air flow, but the disturbance of the connecting piece to the air flow is allowed.
  • the outer surface of the sheet-like component can be kept at the desired temperature by any suitable means known in the art, for example, the temperature of the outer surface of the sheet-like component can be made by the contact of cooling gas, coolant or cold source with the sheet-like component or the principle of semiconductor refrigeration. Below the dew point temperature of at least part of the vapor components.
  • the exhaust gas may flow through one side of the sheet-like member, and cooling air or cooling liquid may be passed through the other side of the sheet-like member.
  • the sheet-shaped member can be sealed around to form a circumferentially closed channel, the exhaust gas passes through the channel, and the outside of the channel is connected to a cold source or cooling liquid.
  • a hollow tube or a heat-conducting solid tube penetrating the sheet-shaped member may be provided in the sheet-shaped member, a cooling liquid may flow in the hollow tube, and a cold source may be connected to the solid tube.
  • the cooling liquid is well-known in the art, and may be, for example, any one or a mixture of liquids such as water, freon, methanol, ethanol, acetone, and ammonia.
  • the cooling gas may be, for example, a mixture of one or more of air, flue gas or any other gas.
  • the sheet-shaped member of the cooling device is preferably a metallic material, such as one of aluminum, copper and steel. kind or several kinds of compound made.
  • a metallic material such as one of aluminum, copper and steel. kind or several kinds of compound made.
  • special anti-corrosion treatments can also be applied to metal components. For example, spraying or passivation of anti-corrosion materials for metal components of steel, copper, aluminum and other materials.
  • the sheet member is a semiconductor thermoelectric sheet
  • the cooling device includes two semiconductor thermoelectric sheets with opposite cold ends.
  • the cooling device includes an upper semiconductor thermoelectric sheet 7 and a lower semiconductor thermoelectric sheet 10.
  • the upper power supply 6 is used to connect a direct current power supply in the upper semiconductor thermoelectric sheet 7 to form
  • the upper hot end 9 and the upper cold end 8 use the lower power supply 13 to connect the DC power supply in the lower semiconductor thermoelectric chip 10 to form the lower hot end 12 and the lower cold end 11.
  • the exhaust gas flows from the upper cold end 8 and the lower cold end 11 Passed between.
  • semiconductor thermoelectric film is also called a semiconductor refrigeration film. It is a refrigeration technology based on the Peltier effect. Its simple working principle is: when a piece of N-type semiconductor material and a piece of P-type semiconductor material are connected to form a galvanic pair, when the DC current is connected in this circuit, energy transfer can occur, and the current flows from the N-type element to the P. The joint of the type element absorbs heat and becomes the cold end; the joint that flows from the P-type element to the N-type element releases heat and becomes the hot end. The temperature difference between the hot and cold ends of the semiconductor refrigeration fins can reach between 40 and 65 degrees Celsius.
  • the temperature of the hot end is reduced by active heat dissipation, the temperature of the cold end will also decrease accordingly, thereby reaching a lower temperature.
  • the exhaust gas flows through the channel between the cold ends of the two semiconductor thermoelectric sheets, and the exhaust gas contacts the cold ends and forms a temperature difference with the cold ends.
  • the cooling device is a plate heat exchanger or a finned tube heat exchanger
  • Plate heat exchanger is a kind of heat exchanger formed by pressing thin metal plates into heat exchange plates with a certain corrugated shape, then stacking them, and fastening them with splints and bolts. Thin rectangular channels are formed between the plates, and heat exchange is performed through the plates. The working fluid flows through the narrow and tortuous channel formed between the two plates. The circulating cooling water and the exhaust gas pass through two adjacent channels respectively, and there is an interlayer plate in the middle to separate the two, and the heat exchange is carried out through the plate. The small spacing of the plate heat exchanger and the long stroke are conducive to the formation of a higher proportion of boundary layer space. When a plate heat exchanger is used, the heat exchange plates constitute the sheet-shaped member.
  • the fins constitute the sheet-shaped member, and the outer diameter D of the fin corresponds to the length of the sheet-shaped member.
  • the fin pitch can be used to represent the spacing between the outer surfaces of the sheet-like components.
  • the fin pitch t is preferably less than 15 mm, more preferably less than 10 mm, more preferably less than 9 mm, more preferably less than 8 mm, and more preferably less than 5 mm.
  • the fin height h is preferably greater than 10 mm, more preferably greater than 15 mm, and more preferably greater than 18 mm.
  • Finned tube heat exchangers are well known to those skilled in the art.
  • Finned tube also known as fin tube or fin tube
  • the base tube is usually a round tube, but can also be a flat tube or an oval tube.
  • the shape of the fin can be any suitable shape, and the fin can be installed inside the tube and/or outside the tube, depending on the application of the heat exchanger and the specific fluid type inside and outside the base tube of the heat exchanger.
  • the base tube of the finned tube heat exchanger can be filled with coolant, the exhaust gas flows between the fins outside the tube, and the heat of the exhaust gas is transferred to the cooling liquid in the tube through the fins and the tube wall, thereby realizing the heat inside and outside the fin tube exchange.
  • the finned tube heat exchanger used is a finned heat tube heat exchanger.
  • the heat pipe is also called "closed two-phase heat transfer system", that is, a device that transfers heat in a closed system by relying on the phase change of the fluid (liquid phase becomes vapor phase and vapor phase becomes liquid phase).
  • the heat pipe has excellent heat transfer characteristics due to the heat transfer by the phase change of the working fluid.
  • the equivalent thermal conductivity of heat pipes is dozens or even hundreds of times higher than that of copper and aluminum, so it is called super-conductor.
  • the heat pipe has good axial isothermal properties when transmitting the same power, and can form a larger heat transfer temperature difference.
  • a typical heat pipe heat exchanger is composed of a tube shell, a liquid wick and an end cap.
  • the inside of the tube is pumped to a certain negative pressure and then filled with an appropriate amount of working liquid, so that the capillary porous material of the liquid wick close to the inner wall of the tube is filled with liquid. seal.
  • One end of the tube is the evaporation section (heating section), and the other end is the condensation section (cooling section).
  • an adiabatic section can be arranged between the two sections.
  • the cooling device may also be an internal finned tube heat exchanger.
  • the inner finned tube heat exchanger improves the performance of the heat exchanger by expanding the surface inside the heat exchange tube and enhancing the heat transfer in the tube.
  • the inner fin tube usually adopts vertical straight ribs.
  • the system and method of the present invention can be used in the exhaust pipe of automobile exhaust, and an internal finned tube heat exchanger can be selected, for example, a petal-shaped tube heat exchanger with a cross section as shown in FIG. 10 The heat exchanger replaces the exhaust pipe from the three-way catalytic converter or the middle muffler to the tail muffler.
  • the air flow channel of the tubular heat exchanger includes a central cylindrical channel and a plurality of plate-shaped channels of the same size located around the cylindrical channel.
  • the plate-shaped channels extend in the direction of the central axis of the cylindrical channel and are separated from the cylindrical channel.
  • the central shaft extends radially outwards, and the plate-shaped channel communicates with the cylindrical channel.
  • Each plate-shaped channel is composed of two parallel plates, and a plurality of plate-shaped channels are evenly distributed around the circumference of the cylindrical channel.
  • the internal diameter of the cross section of the cylindrical channel in the center of the air flow channel of the tubular heat exchanger can be 20-60mm, preferably 30-50mm, more preferably 40mm; the diameter of the outer edge of the plate-shaped channel can be 100-200mm, preferably 170- 220mm, more preferably 150mm; the angle between adjacent plate-shaped channels can be 20-40 degrees, preferably 30 degrees.
  • air sweeps over the outer surface of the tube heat exchanger to cool the exhaust gas.
  • two or more (for example, three, four, five or more) cooling devices can be arranged side by side on the cross section of the exhaust gas flow direction.
  • Device in which multiple cooling devices are separated from each other by an appropriate distance), as shown in Figure 3.
  • two or more sets (for example, three, four, five or more sets) of cooling devices can be arranged along the exhaust gas flow direction, and each set of cooling devices is located in the exhaust gas flow direction.
  • the adjacent two sets of cooling devices can be arranged in a row or staggered, as shown in Figure 4.
  • the Reynolds number, boundary layer thickness, thermophoretic force and viscous drag force are calculated separately for each cooling device.
  • a spray device 3 may be provided on one side of the cooling device 2, and the spray device 3 is used to spray any suitable liquid on the outer surface of the sheet member, including water, Any one or a mixture of aqueous solutions and organic solvents is used to clean the outer surface of the sheet-shaped member to prevent fouling on the wall surface, and at the same time, it can also remove the liquid droplets that wet settled on the wall surface.
  • a spray device that sprays the outer surface of the sheet-shaped member may be provided on both sides of the cooling device.
  • the spray device can be arranged inside the gaseous pollutant removal device, or can be arranged outside the gaseous pollutant removal device, for example, can be arranged in the airflow channel upstream of the gaseous pollutant removal device.
  • the spray device is close to the sheet-shaped member to have a better washing effect.
  • a device for pretreatment of the exhaust gas may be provided.
  • an injection device for the exhaust gas may be installed upstream of the cooling device for injecting substances that can form vapor in the exhaust gas into the exhaust gas to increase the content of the exhaust gas.
  • the injecting device can also be used to inject acidic substances into the exhaust gas to produce an acid mist with a high dew point temperature; the injecting device can also be used to inject oxidizing substances into the exhaust gas And/or alkaline substances to modify certain gaseous components in the exhaust gas.
  • the descriptions of the substances, acidic substances, oxidizing substances, and alkaline substances that can form vapor in the exhaust gas are as described above.
  • the injecting device for exhaust gas may be one or more injecting devices, or an injecting device with two or more nozzles, and different nozzles can inject different substances.
  • the injection device can be used to inject any one, any two, or any more of substances that can form vapor in the exhaust gas, acidic substances, oxidizing substances, and alkaline substances.
  • any one, any two, or any more of substances that can form vapor in the exhaust gas, acidic substances, oxidizing substances, and alkaline substances can be injected through multiple injection devices.
  • An injection device with two or more nozzles injects different substances through different nozzles, and can also inject a mixture of different substances through the same nozzle of the same injection device, provided that the different substances in the mixture are not A chemical reaction will occur (understandably, for example, acidic substances and alkaline substances cannot be mixed together and sprayed through a nozzle).
  • Any one of substances that can form vapor in the exhaust gas, acidic substances, oxidizing substances, and alkaline substances can optionally be sprayed into its pure substance or solution form, and can also optionally be in liquid form or gaseous form ( For example, in the form of gas or vapor) is sprayed, for example, for water, atomized water droplets can be sprayed, or water vapor can be sprayed.
  • a device for oxidizing the exhaust gas may also be provided upstream of the cooling device, such as a photocatalytic oxidation device.
  • a device for example, an air compressor for pressurizing the exhaust gas may be provided upstream of the cooling device.
  • Various injection devices, oxidation treatment devices, and pressurizing devices can be optionally provided according to requirements, for example, all of them can be provided, or only one, two or more of them can be provided.
  • These pretreatment devices can be arranged inside or outside the gaseous pollutant removal device, for example, can be arranged in the airflow channel upstream of the gaseous pollutant removal device. The positions of these pretreatment devices are not particularly limited, and can be set as required.
  • the pressure device may be set after the injection device and/or the oxidation treatment device. It should be understood that, in order to enhance the pretreatment effect, these pretreatment devices are preferably far away from the cooling device, so that the exhaust gas is sufficiently pretreated before passing through the cooling device. When these pretreatment devices and a spray device for spraying the outer surface of the sheet-like member exist simultaneously, it is preferable that the distance between these pretreatment devices and the sheet-like member is greater than the distance between the spray device and the sheet-like member.
  • the escaped droplets can act as condensation nuclei to absorb moisture and grow up. Therefore, in some embodiments, other particulate matter trapping devices 4, such as demisters, dust collectors, etc., can be provided after the cooling device.
  • the grown droplets are captured again, as shown in Figure 7.
  • the dust collector may be, for example, a wet electric dust collector or a Venturi dust collector.
  • the particulate matter trapping device can be arranged inside or outside the gaseous pollutant removal device, for example, it can be arranged in the airflow channel downstream of the gaseous pollutant removal device.
  • the spraying device 3 may be provided on one or both sides of the cooling device, while other particulate matter trapping devices 4 are provided after the cooling device, as shown in FIG. 8.
  • a drainage channel 5 can be provided in the lower part of the gaseous pollutant removal device to facilitate the flow of liquid droplets, or the drainage channel 5 can introduce liquid droplets into the container for recovery. It should be understood that the drainage channel can be provided in any gaseous pollutant removal device described in the present invention, and is not limited to the specific structure shown in FIG. 9.
  • the exhaust gas described in the present invention can be any exhaust gas containing gaseous pollutants, for example, it can be oil and gas containing low-boiling organic matter discharged from a gas station, high-humidity clean flue gas containing organic matter after dedusting and desulfurization of coal-fired boilers, and after natural gas combustion
  • the high-humidity flue gas containing nitrogen oxides and organic components, the high-humidity exhaust gas containing acetic acid and furfural components emitted from the furfural production workshop, the high-humidity exhaust gas emitted from the wood processing workshop and the air containing volatile organic compounds and acid gases It also includes vehicle exhaust emitted during the operation of fuel vehicles (such as gasoline- or diesel-burning vehicles).
  • the exhaust gas of the present invention includes, but is not limited to, high-humidity exhaust gas, especially high-humidity exhaust gas after water spray treatment.
  • the exhaust gas preferably mainly contains gaseous pollutants, where "mainly contains” means that the content of gaseous pollutants in the exhaust gas is higher than that of any other type of pollutants (for example, particulate pollutants, that is, they exist in particulate form in the exhaust gas).
  • the content of pollutants or the content of gaseous pollutants is higher than the sum of the content of all other types of pollutants.
  • the vapor content can be increased by pretreatment, such as increasing its water vapor content (ie, moisture content, for example, by adding steam, Pre-cooling, spray water, etc.) or spray alcohol vapor, and then pass through the gaseous pollutant removal device.
  • pretreatment such as increasing its water vapor content (ie, moisture content, for example, by adding steam, Pre-cooling, spray water, etc.) or spray alcohol vapor, and then pass through the gaseous pollutant removal device.
  • a nozzle or spray device can be added in front of the gaseous pollutant removal device to spray one or more mixtures of water or ethanol or other organic substances to increase the vapor content in the exhaust gas; it can also be added before the gaseous pollutant removal device Pre-heat exchanger, to pre-cool the exhaust gas and increase the vapor content of the exhaust gas (including increasing the relative humidity of the exhaust gas or increasing the relative content of other vapors in the exhaust gas).
  • the preheat exchanger form can be any form of heat exchanger, such as ordinary bare tube heat exchanger.
  • the conventional atomization spray method is to spray the liquid substance into the gas to be purified through various atomization methods. Due to the limitation of the atomization ability and the trapping ability, the sprayed droplet size is more than 20-100 microns (convenient for the The latter is trapped in the mist eliminator), the specific surface area of the droplets is small. After the gaseous pollutants are adsorbed on the droplets of the vapor substance, if they can be absorbed by them, they can be further adsorbed, if they cannot be absorbed by them. , The surface adsorption will no longer be captured after the completion of the surface adsorption, due to the small specific surface area of the sprayed droplets, at this time the capture efficiency of other gaseous pollutants is not high. Generally, after the gaseous pollutants are captured, the sprayed droplets will settle by gravity or other inertial force methods and then be collected by the mist eliminator. There is no wet sedimentation, especially in the cloud removal process.
  • Oil and gas are the volatile matter of gasoline. Usually, a large amount of oil and gas volatilize at the exhaust port of gasoline storage tank, which needs to be condensed and recovered, and finally control its emission concentration.
  • Gasoline components are C4-C12, of which C4-C6 accounts for 35%, and C7-C12 accounts for 65%.
  • C4 and C5 are the main components in oil and gas.
  • pentane has a boiling point of 36°C
  • isopentane has a boiling point of 28°C
  • Neopentane has a boiling point of 10°C
  • butane has a boiling point of 0.50°C
  • isobutane has a boiling point of -11.73°C. It is a gas at room temperature, and it is a gaseous pollutant.
  • the previous recovery plan was to use a tube heat exchanger to cool down to -15°C and recover its condensate.
  • the tube heat exchanger has a weak interception capacity for fine particles.
  • the removal efficiency is below 20%. If higher removal efficiency is required, it is necessary to reduce the temperature to a lower temperature or pressurize the oil and gas to promote condensation.
  • the change of the scheme is: the gaseous pollutant removal device is used to pass the oil and gas discharged from the gasoline storage tank.
  • the gaseous pollutant removal device is in the form of a multi-row finned tube heat exchanger.
  • the oil and gas pass outside the finned tube and the airflow velocity is 7m. /s
  • the working medium in the fin tube is Freon 134A
  • the working medium temperature is -15°C
  • the fin pitch is 5mm
  • the fin height is 15mm
  • the outer diameter of the fin tube is 55mm
  • the temperature of the outer surface of the fin is lower than -10°C.
  • a spray device is arranged to spray ethanol solution.
  • the heat exchanger exchanges part of the heat in the oil and gas to reduce the temperature of the oil and gas, causing some of the pollutants such as pentane, isopentane, and neopentane to condense into mist droplets.
  • the formation of mist droplets will also pollute the rest of the gas in the exhaust gas.
  • the alkane and isobutane are adsorbed, and then through the thermophoresis effect between the fin tubes, the wet sedimentation on the outer surface of the fins, the accumulation of a certain amount, the dripping, and the recovery through the liquid discharge port.
  • the ethanol solution with a low freezing point is sprayed to form atomization, which can wash the outer surface of the fin and strengthen the recovery of the captured oil and gas droplets.
  • the overall removal/recovery efficiency of oil and gas pollutants is over 90%, and the recovered oil and gas pollutants can be further dissolved into gasoline for reuse.
  • a furfural production plant with a process exhaust residue positions 30,000 Nm 3 / h,, moisture saturated temperature around 80 °C, acetic acid containing 70mg / Nm 3, furfural 70mg / Nm 3, formaldehyde 5mg / Nm 3, SO 3 12mg /Nm 3 , and a small amount of dust, with a significant sour smell.
  • the airflow channel connected to the exhaust port of the slag bin first passes through the photocatalytic oxidation system to oxidize part of the gaseous organic matter.
  • Part of the gaseous organic matter is completely oxidized and decomposed into CO 2 and water, and most of the remaining gaseous organic matter is oxidized to higher boiling point organic matter. , In order to be absorbed by the droplets.
  • the finned tube is metal composite rolling
  • the fin pitch is 6mm
  • the fin height is 16mm
  • the outside of the fin tube With a diameter of 64mm, 20°C circulating water flows in the base tube, and the temperature of the outer surface of the fin is about 30°C, which is much lower than the acid dew point and water dew point temperature of the exhaust gas.
  • Spraying devices are also arranged on both sides of the condensing section (in the clean flue) to spray the aqueous solution.
  • the finned tube heat exchanger exchanges part of the heat in the wet flue gas to cool the exhaust gas.
  • the SO 3 , acetic acid and water vapor in the exhaust gas condense into droplets, and other gaseous organic pollutants in the exhaust gas are adsorbed by the droplets, and the droplets wet down.
  • the organic pollutant removal efficiency is over 80% when it accumulates to a certain amount and then drips.
  • a 300MW coal-fired boiler the flue gas produced by wet desulfurization becomes nearly saturated wet flue gas (relative humidity above 95%), the flue gas volume is 1.2 million m 3 /h, the flue gas temperature is about 50 °C, and it contains 2 mg of particulate matter /Nm 3 , sulfuric acid SO 3 vapor 10mg/Nm 3 , volatile organic compounds 13mg/Nm 3 , volatile organic compounds are mainly aliphatic hydrocarbons, halogenated hydrocarbons, aromatic hydrocarbons, oxygen-containing organics, etc., and more than 100 types of gaseous pollutants .
  • the gaseous pollutant removal device is in the form of a metal finned tube heat exchanger, the cooling liquid is 20°C circulating water, and the finned tube is made of metal.
  • the temperature of the outer surface of the fin is about 30°C, which is much lower than the acid dew point and water dew point of the flue gas.
  • the airflow passes through the gaseous pollutant removal device, and the airflow velocity is 4m/s.
  • Spray devices are also arranged on both sides of the gaseous pollutant removal device to spray the aqueous solution.
  • the finned tube heat exchanger exchanges part of the heat in the wet flue gas, realizes the cooling and condensation of the wet flue gas, and forms a large number of droplets, including sulfuric acid mist and water droplets. Volatile organic compounds are adsorbed on the surface of the droplets, and the droplets are in the thermophoretic force. , Driven by the vapor pressure gradient force, wet sedimentation on the outer surface of the fin tube, accumulates to a certain amount and then drips, to achieve the removal of sulfuric acid vapor and volatile organic compounds in the exhaust gas, and the removal efficiency is above 70% and 80%, respectively. the above.
  • the exhausted flue gas after combustion is nearly saturated wet flue gas (relative humidity above 90%), the flue gas temperature is about 80°C, and it contains 100mg/Nm 3 of NO.
  • An ultraviolet photocatalytic oxidation device is installed in the flue to realize the conversion of NO to NO 2 and N 2 O 5 gaseous pollutants (higher boiling point).
  • the gaseous pollutant removal device is installed in the form of ordinary finned tube heat exchange.
  • the fin pitch is 5mm
  • the fin height is 16mm
  • the outer diameter of the fin tube is 64mm
  • the temperature difference between the fin and the smoke is above 10°C
  • the smoke flow rate is 5m/s.
  • the heat exchanger exchanges part of the heat in the wet flue gas to realize the cooling of the wet flue gas and the condensation of water vapor into droplets. After the droplets adsorb/absorb NO 2 and N 2 O 5 , they will settle on the outer surface of the fin tube and accumulate to a certain amount. Dripping, NOx removal efficiency is above 40%.
  • Spray water devices are also arranged on both sides of the gaseous pollutant removal device.
  • the spray water is ordinary process water, and an appropriate amount of Na 2 CO 3 or NaOH is added to flush the fin tube and increase the alkalinity of the condensate to facilitate Absorption of NO x.
  • a demister is installed after the gaseous pollutant removal device, and the water droplets and escaped droplets are further removed by the demister.
  • the exhaust gas temperature is usually about 300°C
  • the relative humidity is 10-20%
  • the water dew point temperature is 50-70°C.
  • hydrocarbon components in the exhaust gas which are in the high-temperature pipeline.
  • the medium is a gaseous state, and after being discharged, it will condense to form fine particles when it meets with the cold air. It is difficult to meet the emission requirements of the National Sixth Standard on hydrocarbon components and particle number concentration.
  • the air flow channel of the tubular heat exchanger includes a central cylindrical channel and a plurality of plate-shaped channels of the same size located around the cylindrical channel.
  • the plate-shaped channels extend in the direction of the central axis of the cylindrical channel and are separated from the cylindrical channel.
  • the central shaft extends radially outwards, and the plate-shaped channel communicates with the cylindrical channel.
  • Each plate-shaped channel is composed of two parallel plates, and a plurality of plate-shaped channels are evenly distributed around the circumference of the cylindrical channel.
  • the cross section of the air flow channel of the tube heat exchanger is shown in Figure 10.
  • the inner diameter of the cross section of the cylindrical channel in the center is 40mm
  • the diameter of the outer edge of the plate-shaped channel is 150mm
  • the clamp between adjacent plate-shaped channels The angle is 30 degrees.
  • the air sweeps over the outer surface of the tube heat exchanger to cool down.
  • the exhaust gas discharge temperature can be reduced from 300 degrees to less than 120 degrees, and the end tube wall temperature drops to about 40 degrees, which is lower than the water dew point temperature of the exhaust gas.
  • the boiling point temperature of most hydrocarbons the petal-shaped tube heat exchanger has a boundary layer between the plates of the plate channel. The water vapor can absorb a large amount of hydrocarbon components after condensing into mist in the boundary layer, which can be removed The removal efficiency of the hydrocarbon components and the number of particles in the exhaust gas is about 70%.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Treating Waste Gases (AREA)
  • Gas Separation By Absorption (AREA)

Abstract

去除废气中的气态污染物的方法和***，利用包含相互平行的片状构件的气态污染物去除装置(1)，使废气在片状构件之间的通道中通过，片状构件外表面温度低于废气中至少部分蒸气的露点温度，通过对废气冷却，废气中的蒸气凝结而形成液滴，液滴利用其高比表面积对气态物质进行吸附，再湿沉降到所述片状构件的外表面上，实现气态物质在废气中被去除；液滴聚集到一定量后滴落，可对气态污染物进行回收再利用。所述方法和***可以有效去除废气中的气态污染物，特别是高湿废气中的蒸气污染物及难溶类气体污染物，降低其浓度。

Description

废气净化***及净化方法 技术领域
本发明涉及工业废气及空气净化领域，具体涉及去除废气中的气态污染物，特别是含湿废气中的气态污染物的方法和***。
背景技术
气态污染物是在常态、常压下以分子状态存在的污染物。气态污染物包括气体污染物和蒸气污染物。气体是在常温、常压下以气体形式存在的物质。常见的气体污染物有：CO、SO 2、NO 2、NH 3、H 2S、低沸点有机物(如丙烷、丁烷等)等。蒸气是常温下为液态或固态的物质蒸发出来的气体，例如固体升华或液体挥发而形成的气态物质。蒸气经过高温转化才能获得，常温下不稳定。可以看到，随着工作温度的变化，蒸汽和气体的范畴会有所变化。例如丁烷沸点是0.50℃，在20℃时，它属于气体；但到-20℃时，丁烷为液态，空气中的丁烷则属于蒸汽。常见的蒸气污染物有：挥发性有机物(简称VOCs)、挥发性重金属(如汞、砷、硒蒸气)、SO 3蒸气等。蒸气遇冷，仍能逐渐恢复原有的固体或液体状态。
气态污染物又可以分为一次污染物和二次污染物。一次污染物是指直接从污染源排到大气中的原始污染物质；二次污染物是指由一次污染物与大气中已有组分，或几种一次污染物之间经过一系列化学或光化学反应而生成的与一次污染物性质不同的新污染物质。在大气污染控制中受到普遍重视的一次污染物有硫氧化物、氮氧化物、碳氧化物以及有机化合物等；二次污染物有硫酸烟雾和光化学烟雾。
通常对于易溶于水的气体污染物，如SO 2、NH 3等，可以通过水喷淋将其吸收进水体中，来实现从废气中的去除；但对于难溶于水的气体污染物，如丁烷，常规水喷淋时，由于其难溶于水，吸收效果差，难于去除，需要通过燃烧分解或者活性炭吸附的方式进行去除，但当废气中湿度较高时，燃烧难于持续，活性炭会因优先吸附水蒸汽而难于对丁烷进行吸附，皆难实现良好的去除效果。
而蒸气污染物，如SO 3蒸气，在水喷淋时可吸湿转化为气溶胶颗粒物，且粒径较小(50纳米左右)，很难被喷淋的水滴碰撞捕获，去除效率也较低。
废气中气态污染物的去除是当前大气环境治理的工作重点，且其中很多气态污染物具有回收价值，其中高湿废气中的气体污染物、蒸气污染物的去除与回收更是当前大气环境治理的技术难点。
发明内容
本发明的目的是提供能有效去除废气中气态污染物和/或回收气态污染物的净化***和净化方法，本发明的方法特别适用于去除和/或回收高湿废气中的难溶性气体污染物和/或蒸气污染物的净化***和净化方法。
本发明一方面提供去除废气中的气态污染物的方法，包括：使废气通过气态污染物去除装置，所述气态污染物去除装置包括气流通道以及布置在气流通道中的冷却装置，所述冷却装置包括至少两个片状构件，所述片状构件基本上相互平行且基本上平行于废气的流动方向，废气从相邻片状构件之间通过，废气流速不高于10m/s；片状构件外表面温度低于废气中至少部分蒸气成分的露点温度，通过对废气进行冷却使得废气中的至少部分蒸气凝结成液滴，废气中的气态污染物吸附在所述液滴上并随所述液滴湿沉降在片状构件外表面。
在一些实施方案中，所述方法进一步包括：回收湿沉降到片状构件外表面的液滴。
在一些实施方案中，所述废气的流速不高于9m/s，或者不高于8m/s，或者不高于7m/s，或者不高于6m/s，或者不高于5m/s，或者不高于4m/s，或者不高于3m/s，或者不高于2m/s，或者不高于1m/s。在一些实施方案中，所述流速包括所述废气在气流通道内的流速。
在一些实施方案中，相邻片状构件之间的间距与片状构件在气流流动方向上的长度的比值小于0.5、小于0.2、小于0.1、或小于0.05。
在一些实施方案中，所述废气的相对湿度大于等于60％、大于等于80％或大于等于90％。
在一些实施方案中，所述冷却装置是板式换热器。
在一些实施方案中，所述冷却装置是翅片管换热器，换热器上的翅片构成所述片状构件。
在一些实施方案中，所述翅片管换热器是翅片热管换热器。
在一些实施方案中，所述冷却装置由金属材料制成。
在一些实施方案中，所述冷却装置中的钢、铜、铝材质的金属构件经防腐材料喷涂处理或钝化处理。
在一些实施方案中，所述片状构件是半导体热电片，所述冷却装置包括两个冷端相对的半导体热电片，废气从两个半导体热电片的冷端之间通过。
在一些实施方案中，在使废气通过冷却装置之前或之时对废气进行预处理，所述预处理包括提高废气中的蒸气含量、向废气中添加酸性物质、对废气进行氧化处理、向废气中添加碱性物质、对废气进行加压中的任意一项或几项。
在一些实施方案中，所述提高废气中的蒸气含量包括向废气中喷入可在废气中形成蒸气的物质。在优选的实施方案中，这些物质优选在废气降温冷却的过程中温度降至其露点温度以下，从而能够形成液滴。在一些实施方案中，这些物质是水、乙醇、乙二醇、其 它可在废气中以蒸气状态存在的物质(例如有机物)、或含有其中任何一种的溶液，或者这些物质的蒸气。
在一些实施方案中，所述酸性物质是可在废气中与水蒸气结合形成具有高露点温度的酸雾的酸性物质，例如SO 3，HCl和/或醋酸中的一种或更多种。
在一些实施方案中，所述碱性物质是可以与部分气态污染物反应，产生沸点更高和/或更易溶于水的物质，例如氨气NH 3、碳酸钠、生石灰CaO、或者氢氧化钠或氢氧化钠溶液中的一种或更多种。
在一些实施方案中，所述氧化处理包括向废气中添加氧化性物质和/或使废气通过光催化氧化装置。
在一些实施方案中，所述氧化性物质是可以使部分气态污染物氧化为沸点更高和/或更易溶于液滴的物质，例如臭氧、亚氯酸钠中的一种或更多种。
在一些实施方案中，所述方法还包括向所述片状构件的外表面上喷淋水、水溶液、有机溶剂中的任意一种或多种的混合物。
在一些实施方案中，所述气态污染物去除装置包括在废气流动方向的横截面上并列布置的一组冷却装置。
在一些实施方案中，所述气态污染物去除装置包括沿废气流动方向上布置的多组冷却装置，每组冷却装置并列布置于废气流动方向的一个横截面上。
在一些实施方案中，相邻两组冷却装置错排布置或顺排布置。
在一些实施方案中，在所述废气通过所述冷却装置之后，利用其它颗粒物捕集装置进一步去除大粒径液滴颗粒物。
在一些实施方案中，所述其它颗粒物捕集装置是除雾器或除尘器。
在一些实施方案中，所述方法进一步包括使湿沉降到片状构件外表面的液滴滴落或流走。在一些实施方案中，回收滴落或流走的液滴。
在一些实施方案中，使湿沉降到片状构件外表面的液滴流走是通过喷淋将湿沉降到片状构件外表面的液滴冲洗脱离片状构件外表面，再通过引流通道使其流走。
本发明的另一方面提供去除废气中气态污染物的***，包括：供废气通过并进行处理的气态污染物去除装置，所述气态污染物去除装置包括气流通道及布置在气流通道中的冷却装置，所述冷却装置包括至少两个片状构件，所述片状构件基本上相互平行且基本上平行于气流走向。
在一些实施方案中，相邻片状构件之间的间距与片状构件在气流流动方向上的长度的比值小于0.5、小于0.2、小于0.1、或小于0.05。
在一些实施方案中，所述冷却装置是板式换热器。
在一些实施方案中，所述冷却装置是翅片管换热器，换热器上的翅片构成所述片状构件。
在一些实施方案中，所述翅片管换热器是翅片热管换热器。
在一些实施方案中，所述冷却装置由金属材料制成。
在一些实施方案中，所述冷却装置中的钢、铜、铝材质的金属构件经防腐材料喷涂处理或钝化处理。
在一些实施方案中，所述片状构件是半导体热电片，所述冷却装置包括两个冷端相对的半导体热电片。
在一些实施方案中，在所述冷却装置的上游侧设置有喷入装置，用于向废气中喷入可在废气中形成蒸气的物质、氧化性物质、酸性物质、碱性物质中的任意一种或几种。
在一些实施方案中，在冷却装置的上游侧设置有氧化装置，用于对废气进行氧化处理。
在一些实施方案中，所述氧化装置是光催化氧化装置。
在一些实施方案中，在冷却装置的上游侧设置有加压装置，用于对废气进行加压处理。
在一些实施方案中，在所述气态污染物去除装置的一侧或两侧设置有喷淋装置，用于向所述片状构件的外表面上喷水、水溶液、有机溶剂中的一种或几种的混合物。
在一些实施方案中，所述气态污染物去除装置包括在气流通道的横截面上并列布置的一组冷却装置。
在一些实施方案中，所述气态污染物去除装置包括沿着气流通道走向上布置的多组冷却装置，每组冷却装置并列布置于气流通道的一个横截面上。
在一些实施方案中，相邻两组冷却装置错排布置或顺排布置。
在一些实施方案中，冷却装置之后设置其它颗粒物捕集装置。
在一些实施方案中，所述其它颗粒物捕集装置是除雾器或除尘器。
在一些实施方案中，所述***还包括引流通道，用于使液滴通过所述引流通道引出和/或回收。
本发明利用气态污染物去除装置处理废气，其结构有利于让蒸气凝结形成液滴，借助液滴高比表面积高效吸附气态污染物；进一步采用金属片状构件，其导热性能强，作为冷却器时，可在片状构件表面与废气间形成较大的温度梯度，利用热泳力推动吸附了气态污染物的液滴向片状构件表面移动；液滴湿沉降在片状构件外表面，聚集到一定量后滴落，实现气态污染物在废气中被去除。
具体而言，本发明涉及以下方案：
方案1.去除废气中的气态污染物的方法，包括：使废气通过气态污染物去除装置，所述气态污染物去除装置包括气流通道以及布置在气流通道中的冷却装置，所述冷却装置包括至少两个片状构件，所述片状构件基本上相互平行且基本上平行于废气的流动方向，废气从相邻片状构件之间通过，废气流速不高于10m/s；片状构件外表面温度低于废气中至少部分蒸气成分的露点温度，通过对废气进行冷却使得废气中的至少部分蒸气凝结成液滴，废气中的气态污染物吸附在所述液滴上并随所述液滴湿沉降在片状构件外表 面。
方案2.根据方案1的方法，进一步包括：回收湿沉降到片状构件外表面的液滴。
方案3.根据方案1或2的方法，其中所述废气的流速不高于5m/s。
方案4.根据方案1-3任一项的方法，其中相邻片状构件之间的间距与片状构件在气流流动方向上的长度的比值小于0.5。
方案5.根据方案1-4任一项的方法，其中所述废气的相对湿度大于等于60％。
方案6.根据方案1-5任一项的方法，其中所述冷却装置是板式换热器。
方案7.根据方案1-5任一项的方法，其中所述冷却装置是翅片管换热器，换热器上的翅片构成所述片状构件。
方案8.根据方案7的方法，其中所述翅片管换热器是翅片热管换热器。
方案9.根据方案6-8任一项的方法，其中所述冷却装置由金属材料制成。
方案10.根据方案9的方法，其中所述冷却装置中的钢、铜、铝材质的金属构件经防腐材料喷涂处理或钝化处理。
方案11.根据方案1-5任一项的方法，其中所述片状构件是半导体热电片，所述冷却装置包括两个冷端相对的半导体热电片，废气从两个半导体热电片的冷端之间通过。
方案12.根据方案1-11任一项的方法，其中在使废气通过冷却装置之前对废气进行预处理，所述预处理包括提高废气中的蒸气含量、向废气中添加酸性物质、对废气进行氧化处理、向废气中添加碱性物质、对废气进行加压中的任意一项或几项。
方案13.根据方案12的方法，其中所述提高废气中的蒸气含量包括向废气中喷入可在废气中形成蒸气的物质。
方案14.根据方案12的方法，其中所述氧化处理包括向废气中添加氧化性物质和/或使废气通过光催化氧化装置。
方案15.根据方案1-14任一项的方法，还包括向所述片状构件的外表面上喷淋水、水溶液、有机溶剂中的任意一种或多种的混合物。
方案16.根据方案1-15任一项的方法，其中所述气态污染物去除装置包括在废气流动方向的横截面上并列布置的一组冷却装置。
方案17.根据方案1-16任一项的方法，其中所述气态污染物去除装置包括沿废气流动方向上布置的多组冷却装置，每组冷却装置并列布置于废气流动方向的一个横截面上。
方案18.根据方案17的方法，其中相邻两组冷却装置错排布置或顺排布置。
方案19.根据方案1-18任一项的方法，其中在所述废气通过所述冷却装置之后，利用其它颗粒物捕集装置进一步去除大粒径液滴颗粒物。
方案20.根据方案19的方法，其中所述其它颗粒物捕集装置是除雾器或除尘器。
方案21.根据方案1-19的方法，其中进一步包括使湿沉降到片状构件外表面的液滴滴落或流走。
方案22.根据方案21的方法，其中使湿沉降到片状构件外表面的液滴流走是通过喷 淋将湿沉降到片状构件外表面的液滴冲洗脱离片状构件外表面，再通过引流通道使其流走。
方案23.去除废气中气态污染物的***，包括：供废气通过并进行处理的气态污染物去除装置，所述气态污染物去除装置包括气流通道及布置在气流通道中的冷却装置，所述冷却装置包括至少两个片状构件，所述片状构件基本上相互平行且基本上平行于气流走向。
方案24.根据方案23的***，其中相邻片状构件之间的间距与片状构件在气流流动方向上的长度的比值小于0.5。
方案25.根据方案23或24的***，其中所述冷却装置是板式换热器。
方案26.根据方案23或24的***，其中所述冷却装置是翅片管换热器，换热器上的翅片构成所述片状构件。
方案27.根据方案26的***，其中所述翅片管换热器是翅片热管换热器。
方案28.根据方案23-27任一项的***，所述冷却装置由金属材料制成。
方案29.根据方案28的***，其中所述冷却装置中的钢、铜、铝材质的金属构件经防腐材料喷涂处理或钝化处理。
方案30.根据方案23的***，其中所述片状构件是半导体热电片，所述冷却装置包括两个冷端相对的半导体热电片。
方案31.根据方案23-30任一项的***，其中在所述冷却装置的上游侧设置有喷入装置，用于向废气中喷入可在废气中形成蒸气的物质、氧化性物质、酸性物质、碱性物质中的任意一种或几种。
方案32.根据方案23-31任一项的***，其中在冷却装置的上游侧设置有氧化装置，用于对废气进行氧化处理。
方案33.根据方案31的***，其中所述氧化装置是光催化氧化装置。
方案34.根据方案23-33任一项的***，其中在冷却装置的上游侧设置有加压装置，用于对废气进行加压处理。
方案35.根据方案23-34任一项的***，其中在所述气态污染物去除装置的一侧或两侧设置有喷淋装置，用于向所述片状构件的外表面上喷水、水溶液、有机溶剂中的一种或几种的混合物。
方案36.根据方案23-35任一项的***，其中所述气态污染物去除装置包括在气流通道的横截面上并列布置的一组冷却装置。
方案37.根据方案23-35任一项的***，其中所述气态污染物去除装置包括沿着气流通道走向上布置的多组冷却装置，每组冷却装置并列布置于气流通道的一个横截面上。
方案38.根据方案37的***，其中相邻两组冷却装置错排布置或顺排布置。
方案39.根据方案23-38任一项的***，其中冷却装置之后，设置其它颗粒物捕集装置。
方案40.根据方案39的***，其中所述其它颗粒物捕集装置是除雾器或除尘器。
方案41.根据方案23-40任一项的***，还包括引流通道，用于使液滴通过所述引流通道引出和/或回收。
方案42.根据方案26的***，其中所述翅片管换热器是内翅片管式换热器。
附图说明
图1是气态污染物去除装置的示意图。
图2是气态污染物去除装置的一个实施方案的结构示意图。
图3是一组冷却装置的排列方式示意图。
图4是多组冷却装置的排列方式示意图。
图5是翅片管换热器的结构示意图。
图6是气态污染物去除装置的另一实施方案的示意图。
图7是气态污染物去除装置的另一实施方案的示意图。
图8是气态污染物去除装置的另一实施方案的示意图。
图9是气态污染物去除装置的另一实施方案的示意图。
图10是花瓣形管式换热器气流通道的横截面示意图。
具体实施方式
为使本发明的目的、技术方案和优点更加清楚明了，下面结合具体实施方式并参照附图，对本发明进一步详细说明。应该理解，这些描述只是示例性的，而并非要限制本发明的范围。此外，在以下说明中，省略了对部分公知结构和技术的描述，以避免不必要地混淆本发明的概念。
除另有说明外，本发明中的术语均应按照本领域中通常的理解方式理解其含义。本发明中关于理论和具体实施方案的说明是为了更好地理解本发明，不应视为对本发明保护范围的限制。
本发明人发现，可以通过小粒径液滴对气态污染物的吸附和/或吸收作用实现对废气中气态污染物的去除。
本发明中，气态污染物是指在废气中以分子形式存在的污染物。气态污染物包括气体污染物和/或蒸气污染物。
本文所述的气体污染物是在废气中以气体形式存在的污染物。气体污染物的沸点低于废气温度，因而以气体形式存在。气体污染物包括但不限于CO、SO 2、NO、NH 3、H 2S、低沸点有机物(如低沸点烷烃，如丙烷、丁烷、异丁烷、新戊烷等)中的任意一种或几种。部分挥发性有机物(简称VOCs)在废气中也可以以气体形式存在，构成气体污染物。对本领域技术人员而言，根据常识即可判断废气中的某种气体组分是否属于气体污染物，可以根据该气体组分的种类、沸点和废气的温度等容易地进行判断。
本文所述的蒸气污染物是指在废气中以蒸气形式存在的污染物。蒸气污染物的沸点高于废气温度，但露点低于废气温度，因而在废气中以蒸气形式存在。蒸气污染物包括但不限于部分挥发性有机物(，例如异戊烷、苯、乙酸、糠醛等)、挥发性重金属(如汞、砷、硒蒸气)、SO 3蒸气(也可被称为硫酸蒸气)等中的任意一种或几种。本领域技术人员而言，根据常识即可判断废气中的某种组分是否属于蒸气污染物，可以根据该组分的种类、沸点和废气的温度等容易地进行判断。
当气体分子(吸附质)运动到液滴(吸附剂)表面时，由于气体分子和液滴表面分子之间的相互作用，气体分子停留在液滴表面上，这种现象称为气体分子在液滴表面的吸附。如气体分子(吸附质)进一步进入到液滴内部形成溶液，这个过程叫做吸收。通常来说液滴(吸附剂)的吸附能力主要与其表面自由能和比表面积正相关。常见液体中水的表面自由能最大；液滴的比表面积通常与其粒径大小成反比，液滴粒径越小，液滴的比表面积越大，因此纳微米级的液滴(例如雾滴，其粒径通常在微米量级)是一种很好的吸附剂。大气环境科学研究中发现雾对于气态污染物，哪怕是疏水(难溶于水)性气态污染物都有很好的吸附效果，雾滴中的疏水性有机化合物的含量较雨滴(粒径通常在毫米量级)中的含量高十至上千倍。
受到上述现象的启发，本发明人发现，可以通过对废气进行降温冷却获得大量小粒径液滴，这些小粒径液滴可以进一步吸附和/或吸收废气中的其它气态污染物，通过热泳力等作用使这些液滴实现湿沉降，聚集形成较大的液珠或液膜并除去，可以有效去除废气中的气态污染物。
含有所述气态污染物的液珠或液膜可以被收集并回收，以对所述气态污染物成分进行再利用。例如油气污染物、焦油污染物等的成分主要成分是有机混合物，将其回收后可以再次添加到汽油或其它油类中，实现再利用。
含有蒸气的废气在降温冷却时能够形成液滴，使废气降温至所含蒸气的露点或露点以下，由于这些蒸气在露点温度发生相变，便可形成液滴。在蒸气具有较高的过饱和度的条件下，可形成小粒径液滴，所述小粒径液滴的粒径可以是纳微米量级的，本发明中，所形成的纳微米量级的小粒径液滴也可被称为雾滴。
本发明的构思可以通过如下非限制性的说明得到更好地理解。为了通过小粒径液滴对气态污染物的吸附和/或吸收作用去除废气中的气态污染物，废气中应当存在A物质和B物质，A物质是指一种或更多种在废气中以蒸气态存在的物质，A物质的温度在废气降温冷却的过程中降至其自身的露点或露点以下，由此形成大量液滴。这些由A物质形成的液滴进一步吸附和/或吸收B物质，湿沉降后进一步聚集成较大的液珠或液膜，随后被除去。A物质可以包含部分蒸气污染物、水蒸气和/或其它任何可以在废气中以蒸气状态存在的物质(例如酒精)，B物质是指蒸气污染物中除作为A物质存在的其它蒸气污染物和/或气体污染物。判断废气中哪些物质属于A物质，哪些物质属于B物质，需要依据各物质的沸点温度、露点温度、目标降温温度等确定，简而言之，露点温度高于目标降温温 度的蒸气属于A物质，露点温度低于目标降温温度的蒸气和气体属于B物质。在一些实施方案中，废气中的气态污染物的一部分包含在A物质中，一部分包含在B物质中。在一些实施方案中，A物质包含水蒸气和部分蒸气污染物，B物质包含气体污染物和部分蒸气污染物，在废气降温冷却的过程中，A物质凝结为液滴，吸收和/或吸附B物质并湿沉降到冷却装置外表面，最终A物质和B物质被有效除去。
为了加强去除效果，可以通过以下两种途径对废气进行预处理：一、增加A物质的量，例如向废气中添加水蒸气或其它可以在废气中以蒸气状态存在的物质(例如酒精)，来增加废气中的蒸气含量，或者向废气中添加酸性物质引入酸雾，或者对废气加压从而提高A物质的分压(相对湿度)；二、对B物质进行改性，以使得B物质更易于被A物质形成的液滴吸收和/或吸附，例如对废气进行氧化处理和/或向废气中添加碱性物质等，这种改性例如可以通过化学反应使至少部分B物质转化为沸点更高的物质和/或在液滴中溶解度更高的物质。
露点温度指在某气体(蒸气)含量和气压都不改变的条件下，冷却到该气体饱和时的温度。露点温度可以根据该气体的不同温度下饱和蒸气分压图查得。以水为例，水的露点温度是水蒸气分压所对应的饱和温度，对于空气所含有的水蒸气而言，其露点温度即是其变为露珠时候的温度。水蒸气的露点温度可被称为水露点温度，酸性气体与废气中的水蒸气结合形成酸雾的露点温度可被称为酸露点温度。本发明中，露点温度可以指废气中存在的任何蒸气的露点温度，既可以指水露点温度或蒸气露点温度，也可以指酸露点温度。
所述蒸气也可以称为蒸气类物质，在本发明中，它是指沸点高于废气温度但露点低于废气温度、在废气中以蒸气状态存在的物质。废气中可以包含一种或更多种蒸气，所述蒸气可以是水蒸气、任何蒸气污染物和/或其它任何可以在废气中以蒸气状态存在的物质(例如乙醇、SO 3、Hg等)，因此，废气中可以包含水蒸气、一种或更多种蒸气污染物和/或其它任何可以在废气中以蒸气状态存在的物质(例如乙醇蒸气、SO 3蒸气、Hg蒸气等)，或它们的混合物。
液滴由废气中的蒸气降温冷却而形成。废气中所含的不同种类的蒸气的露点温度不同，在废气降温冷却过程中，露点较高的蒸气先形成液滴。本发明中，使废气中的所有蒸气均降温至露点或露点以下不是必需的，可以使废气中至少一部分蒸气降温至露点或露点以下形成液滴。
用于形成液滴的蒸气可以是废气中包含的水蒸气、任何蒸气污染物和/或其它任何可以在废气中以蒸气状态存在的物质(例如乙醇)，而不限于水蒸气。应当理解，废气中并不必需含有水蒸气，含有蒸气(任何蒸气类物质)即可。
废气中蒸气的含量没有特别限制，只要在废气降温冷却时能够形成小粒径液滴即可。应当理解，废气中所含有的蒸气越多，在降温冷却时形成的液滴越多，其吸附和/或吸收的其它气态污染物越多，去除效果越好。在一些实施方案中，高湿废气是优选的，例如相对湿度大于等于60％、湿度大于等于80％、或湿度大于等于90％的废气。在一些实施方 案中，可以对废气进行预处理，以提高废气中的蒸气含量，例如向废气中添加可在废气中形成蒸气的物质，这些物质优选在废气降温冷却的过程中温度降至其露点温度以下，从而能够形成液滴。这些物质例如可以是水、乙醇、乙二醇、其它可在废气中以蒸气状态存在的物质(例如有机物)、或含有其中任何一种的溶液，或者这些物质的蒸气。在一些实施方案中，例如可以向废气中喷入这些物质，以提高废气中的蒸气含量。在一些实施方案中，可以使废气的相对湿度达到大于等于60％、大于等于80％、或大于等于90％。所形成的液滴组成随废气中蒸气种类、蒸气露点温度、废气温度、降温温度的不同而不同，可以包括水滴、蒸气污染物降温后形成的液滴、蒸气污染物的水溶液液滴、以及蒸气污染物的乙醇溶液液滴中的一种或多种。
在一些实施方案中，预处理还可以包括对废气进行加压，以提高其中所含蒸气的分压。加压后废气中各组分的分压等比例提高，原不饱和的蒸气组分分压增加后一部分可达到过饱和，从而凝结成液滴，其他蒸气组分即使未达到过饱和，其分压更高也更易于通过小幅度降温凝结成液滴。例如可以使废气先通过加压装置加压后，再通过气态污染物去除装置。所述加压装置例如可以是空气压缩机，对废气进行等温加压，废气的气压例如可以从正常的1个大气压升为大于等于2个大气压、大于等于3个大气压、大于等于4个大气压、或大于等于5个大气压等。
当废气中有酸性气体(如SO 3，HCl，醋酸等)时，会与废气中的水蒸气结合，所形成的物质被称为酸雾，酸雾的凝结温度称为酸露点，它比水露点要高很多。以SO 3为例，其浓度含量越高，酸露点就愈高，废气中的酸露点可达140～160℃，甚至更高。SO 3酸露点可按如下公式计算：
tp＝20LgVso 3+α
式中tp是酸露点温度℃
Vso 3烟气中SO 3体积份数％
α——水分常数，
当水分为5％，α＝184
当水分为10％，α＝194
当水分为15％，α＝201
因此，如果废气中的酸性气体比较多，则能够更快形成小粒径液滴，并且形成更多的小粒径液滴，气态污染物去除效率会更高。
在一些实施方案中，对废气的预处理还可以包括向含有水蒸气的废气(例如高湿废气)中添加可在废气中与水蒸气结合形成具有高露点温度的酸雾的酸性物质，从而更快形成小粒径液滴，并且形成更多的小粒径液滴，提高气态污染物去除效率。。本领域技术人员根据常规的物理化学知识即可知哪些酸性物质可在废气中与水蒸气结合形成具有高露点温度的酸雾，其实例包括SO 3，HCl和/或醋酸等。在一些实施方案中，还可以向废气中同时添加水蒸气和上述的酸性物质。在一些实施方案中，可以向含有水蒸气的废气中喷入 上述的酸性物质。
废气中的蒸气降温所形成的的液滴会进一步吸附其它的气态污染物。如果在吸附剂表面上吸附的气体仅仅只有一分子的厚度，则称作单分子层吸附；如果吸附层厚度超过一分子，则称为多分子层吸附。当吸附质的温度低于其正常沸点时，往往发生多分子层吸附，所以气态污染物的沸点越高，其越容易被吸附。
液滴对于吸附到的气态污染物可进一步的吸收，吸收程度与气态污染物分子的扩散速率、气态污染物在液滴(例如水滴)中的溶解度，在液滴(例如水溶液)中的反应性有关，通常气态污染物在液滴中的溶解度越高，在液滴中能发生反应转化为其他物质，则雾滴对于该类气态污染物的吸收程度越高。
被吸附的气态污染物可以是在废气降温冷却过程中尚未达到其露点温度的那些气态污染物，可以包括尚未达到其露点温度的蒸气污染物和/或气体污染物。。
为了使废气中的其余气态污染物更容易被吸附和/或吸收，对废气的预处理还可以包括将废气中包含的气态污染物转化成具有更高沸点的气态物质(沸点更高的气态物质更容易吸附到液滴上)，或者将废气中包含的气态污染物转化为更易溶于液滴(例如当液滴由水或水溶液组成时，即为更易溶于水)，即在液滴中溶解度更高的气态污染物，这些转化例如可以通过化学反应实现。例如可以向废气添加(例如喷入)氧化性物质和/或碱性物质。所述氧化性物质可以使部分气态污染物氧化为沸点更高和/或更易溶于液滴的物质，氧化性物质的选择取决于废气中的气态污染物成分，例如加入臭氧O 3、亚氯酸钠NaClO 2可以将NO氧化为NO 2，本领域技术人员可以根据气态污染物的成分和一般的物理化学知识确定所使用的氧化性物质。所述氧化性物质的非限制性的实例包括臭氧、亚氯酸钠中的一种或更多种。作为非限制性的实例，例如可以向废气喷入氧化性物质，如臭氧、亚氯酸钠，将废气中的NO氧化为沸点更高，也更易溶于水的NO 2、N 2O 5，以便于被液滴更好地吸收和/或吸附。作为另一个非限制性的实例，，例如可以向废气喷入臭氧，将沸点为167度的糠醛氧化为沸点为232度的糠酸，氧化后形成的糠酸更易形成液滴，通过湿沉降被捕集。所述碱性物质可以与部分气态污染物反应(例如与所述气态污染物一同被液滴吸附并进一步反应)，产生沸点更高和/或更易溶于水的物质。例如可以向废气中添加碱性物质，以使其吸收部分酸性气态污染物。本领域技术人员可以根据气态污染物的成分和一般的物理化学知识确定所使用的碱性物质。所述碱性物质的实例包括氨气NH 3、碳酸钠、生石灰CaO、或者氢氧化钠或氢氧化钠溶液等。作为非限制性的实例，可以向废气中喷入氨气，氨气被液滴吸附，并在液滴中与NO 2、N 2O 5等物质发生反应，从而使得液滴吸附和/或吸收的NO 2、N 2O 5更多。还可以是通过其他方式对废气进行氧化处理，例如使废气通过光催化氧化装置等，以实现将部分气态污染物氧化为沸点更高和/或更易溶于液滴的物质。
对废气进行降温冷却可以使用冷却装置(例如换热器)实现，可以使冷却装置外表面(即冷却装置与废气接触的表面)温度(在本发明中也被称为目标降温温度)低于废气 中至少一部分蒸气的露点温度(这部分蒸气也可被称为A物质)，使得所述至少一部分蒸气在冷却过程中形成液滴。使冷却装置外表面保持一定温度的手段是本领域技术人员熟知的，例如可以通过冷却液或冷却气或其它任何适合的冷源。冷却装置外表面的温度可以依据废气中所含蒸气的种类、含量、露点温度等确定，其可以低于废气中所含的至少一种、至少两种、至少三种或更多种蒸气的露点温度，其至少应低于废气中最高的露点温度，所述废气中最高的露点温度是指在其它条件不变的情况下，废气冷却过程中开始出现冷凝液滴的温度，也可以被理解为废气所含的不同组分中露点温度最高的那种组分的露点温度，这里所说的不同组分指具有露点温度的组分，例如酸雾、水蒸气、或其它蒸气组分等。例如，对于含有酸雾的蒸气，可以使冷却装置外表面的温度低于废气的酸露点温度，即废气中所含酸雾的露点温度，如果废气中存在多种酸雾，则相应地存在多种酸露点温度，此时可使冷却装置外表面的温度低于任何一种更多种酸露点温度，例如低于最高的酸露点温度。例如对于一种废气，水分为10％，含有SO 3的体积浓度为10PPm，另具有5PPm难溶性有机蒸气，依据上述酸露点温度计算公式，其SO 3酸露点温度为94℃，其水露点温度为47℃，可使这种废气通过板式换热器，板式换热器另一侧走20℃循环水，此时板式换热器气侧壁面温度在25℃，废气通过冷壁面，既形成了一定量的硫酸雾滴，也形成了更大量的水雾滴，可对有机蒸气进行高效地吸附。
废气降温冷却过程中形成的液滴大小与其中降温后能形成液滴的蒸气的过饱和度有关。以水蒸气为例，由水汽变为液态水的相变过程称为核化过程。在特定过饱和度下，多个水汽分子可以组成分子团(或称胚芽)。胚芽的形成可以看作是靠水汽分子的随机凝聚而成，其能否稳定地继续存在下去，主要看胚滴的粒径大小与废气中水汽过饱和度大小。研究表明，过饱和度越高，能够稳定存在的胚滴粒径越小，所形成水雾的比表面积越大，吸附能力越强(其理论可参见《大气环境化学.第二版》，高等教育出版社，2006年5月，第五章第三节)。当废气通过冷却装置时，由于在冷却装置表面只有在边界层内才有温度梯度和蒸汽压梯度，只有在边界层内才稳定存在过饱和的蒸气，且越接近冷却装置外表面，其过饱和度越高。所以要使形成的液滴粒径尽量小，发挥液滴的吸附能力，需要冷却装置外表面有较大的边界层空间。
边界层是当流体流过固体壁面时，固体壁面上形成的流动薄层，又称流动边界层、附面层。通常认为温度梯度、流速梯度主要存在在边界层内，边界层以上的流体流动可看作同温同流速的。边界层厚度的计算公式为：
Figure PCTCN2021071121-appb-000001
其中θ是边界层厚度，L是特征长度，Re是雷诺数。雷诺数越小边界层厚度越大。
特征长度和雷诺数的计算在本领域技术人员掌握的技术之内。雷诺数是在流动条件下流体的惯性力与粘性力的无量纲比值。雷诺数可以表征流体流动特性(即层流或湍流)。雷诺数Re的计算公式为：
Figure PCTCN2021071121-appb-000002
式中：ρ是流体密度，v是流体流速，μ是＝流体粘度，L是特征长度。
术语“特征长度”是本领域技术人员熟知的。例如，当气体流过圆形管道时，术语“特征长度”为管道的当量直径。当流体流过平板时，术语“特征长度”为自板端向后流过的距离。
本发明的方法中，优选废气流速小于等于10m/s，更优选小于等于9m/s，更优选小于等于8m/s，更优选小于等于7m/s，更优选小于等于6m/s，更优选小于等于5m/s，更优选小于等于4m/s，更优选小于等于3m/s，更优选小于等于2m/s，更优选小于等于1m/s。
本发明的冷却装置采用片状构件。在一些实施方案中，所述冷却装置包括至少两个平行的片状构件，所述片状构件基本上相互平行且基本上平行于废气的流动方向，相邻片状构件之间形成通道，以使得废气在通道间通过。该片状构件外表面的温度低于废气中至少一部分蒸气的露点温度。片状构件可以提供较大的与废气的接触面积，从而提供较大的边界层面积。优选相邻片状构件形成的通道在气流流动方向上的长度较长为好，例如至少30mm，优选至少45mm，更优选为至少60mm，更优选为至少90mm，以使得气流通过片状构件的停留时间足够长。优选片状构件之间的间距较小为好，例如45mm以下，更优选为30mm以下，更优选为15mm以下，更优选为10mm以下，更优选为5mm以下，以使得边界层在冷却装置所占空间中的占比较大。进一步优选地，相邻片状构件之间的间距与片状构件在气流流动方向上的长度的比值小于0.5、小于0.2、小于0.1、或小于0.05。相邻片状构件之间的间距可以是相邻片状构件的中心线之间的间距；也可以是相邻片状构件的相邻外表面之间的间距，例如上部片状构件的下表面与下部片状构件的上表面之间的间距(当片状构件上下相邻放置时)，或者外侧片状构件的内表面与内侧片状构件的外表面之间的间距(当片状构件内外相邻放置时，所述内外是指相对于观察者而言，靠近观察者的一侧称为外，远离观察者的一侧称为内)。
当使用片状构件形式的冷却装置时，当片状构件的表面温度低于至少一部分蒸气组分的露点温度时，该蒸气组分一部分凝结在冷却装置壁面上，另一部分会在边界层内凝结形成液滴，由于边界层内可形成很高的该蒸气组分的过饱和度(可达200％以上)，此情况下该蒸气组分可通过均相成核，形成的液滴粒径小于1微米，甚至只有10纳米左右，数浓度可达到10 5-10 7个/cm 3，比表面积很高，从而吸附和/或吸收尚未达到其露点温度的其它气态污染物。即使其它气态污染物难于被该蒸气组分的液滴吸收，也能有很高的吸附捕集效果。吸附完的液滴多小于10微米，难于重力沉降，但可在适宜的风速下(例如10m/s，优选5m/s以下)通过边界层内的热泳力和蒸气压梯度力湿沉降并到冷却装置壁面上，随后可被除去。
湿沉降和干沉降通常是指大气中颗粒物的两种主要自净机制。干沉降也叫重力沉降，是指颗粒物通过重力沉降，与干扰物表面相碰撞而被捕获的过程，统称干沉降(dry  deposition)，重力沉降仅对直径大于10微米的颗粒物有效。湿沉降是指作气体中的污染物凝结成核后再从气体中被清除的过程，分为云内清除和云下清除两个阶段。云下清除指的是液滴在降落过程中，通过惯性碰并过程和布朗扩散作用俘获气体中颗粒物，使之从气体中清除，主要对较大颗粒有效。云内清除是指细颗粒物充当凝结核，凝结增长，通过布朗运动、泳移(包括热泳、蒸气压梯度力的推动等)或惯性碰并过程，在气体内清除大量细颗粒物，主要对1微米以下的细颗粒物有效。本发明中所使用的术语“湿沉降”是指废气中的气态污染物凝结成核之后，再通过惯性碰并、布朗运动和/或泳移而被清除的过程。
本发明所使用的术语“热泳力”是指由于冷却装置外表面与气流之间的温度梯度(由冷却装置外表面与气流之间的温差而导致)形成的推动微小颗粒物(如液滴)向冷壁运动的力，温差越大，温度梯度越大，热泳力越大。
颗粒物在具有温度梯度的流体中运动时，由于冷热区分子与其碰撞时传递的动量不同，而表现为受到与温度梯度方向相反的力(即热泳力)的作用，使颗粒物产生与温度梯度相反的运动速度，并沉积于低温表面上，这被称为热泳效应。由于温度梯度存在于冷壁面的边界层内，热泳效应是短程效应，仅在壁面边界层中发生。
热泳力的计算公式(参见《气溶胶力学》，科学出版社，1960年)为：
Figure PCTCN2021071121-appb-000003
式中F是热泳力，Xa是气体导热系数，Xi是颗粒物导热系数，η是气体粘性系数，R是颗粒物半径，Γa是温度梯度，ρ是气体密度，T是气体温度。由于温度梯度存在于边界层内，在相同边界层厚度的情况下，温差越大，则温度梯度越大。
根据流体力学理论，粘性曳力是气体流动中对所接触的颗粒物(例如液滴)形成的力，粘性曳力的大小与流速的平方成正比，与颗粒物直径的平方成正比。粘性曳力的计算公式为：
Figure PCTCN2021071121-appb-000004
式中：F是粘性曳力，ξ是曳力系数，πR 2-颗粒物投影面积，ρ-气体密度，U-气体流速。
由热泳力和粘性曳力的计算公式可知，热泳力大小与温度梯度成正比，与液滴直径的一次方成正比，而粘性曳力的大小与液滴直径的平方成正比，因此在相同条件下，液滴直径越小，热泳力相对粘性曳力的比值越大，利用热泳力实现沉降的效果越明显。气流流速越低，粘性曳力越小，利用热泳力实现沉降的效果越明显。
对于露点温度高于冷却装置外表面温度的蒸气而言，其一部分冷凝在壁面上，壁面处蒸气压下降，另一部分在边界层中被降温从而形成过饱和蒸气，该过饱和蒸气与冷却装置外表面间会产生蒸汽压梯度差，此时液滴会受到指向冷却装置外表面的蒸汽压梯度力，此力可以推动该液滴沉降到冷却装置外表面上。
蒸气压梯度力的原理是，过饱和蒸气在冷凝时，会引起气流与冷凝壁面间的蒸气压梯度，并形成向着冷凝壁面的气体分子流，造成气体对其中的颗粒物相对两面的分子碰撞不同并致使颗粒物迁移，其运动方向指向冷凝面。与热泳力一样，蒸气压梯度力也是微观力，蒸气压梯度主要存在于冷壁面的边界层内。蒸汽压梯度力的计算较为复杂，可以看做介于不考虑其他气体成分分压，仅存在蒸气压力梯度时，所产生的气压梯度力，与假定气体总气压不变，蒸气分压变化时产生的斯蒂芬流的推动力这两个计算数值之间的一个数值。简单地说，蒸气压梯度力大小与蒸气压梯度成正比，。废气中可冷凝成液滴的蒸气含量越高，边界层厚度越小，蒸气压梯度越大。
蒸汽压梯度力可与热泳力叠加，共同推动液滴湿沉降到冷却装置外表面上。
湿沉降到冷却装置外表面上的液滴可以聚集成较大的液滴，可以使其自然滴落或流走，从而被去除，实现气态污染物的去除。在一些方案中，可以通过喷淋将这些液滴冲洗脱离片状构件外表面，使其流走。在一些实施方案中，可以使这些液滴通过引流通道流走。在一些实施方案中，可以收集滴落或流走的液滴，以进行回收，便于再利用。在一些实施方案中，可以将滴落或流走的液滴收集到容器中。在另一些实施方案中，还可以通过引流通道将流走的液滴引流收集。
如图1所示，本发明的气态污染物去除装置1具有供废气通过的气流通道，气流通道中设置冷却装置2，冷却装置包括至少两个片状构件，所述片状构件基本上相互平行且基本上平行于气流走向。
为去除废气中的气态污染物，可使废气通过气态污染物去除装置并从相邻片状构件之间通过，控制废气流速不高于10m/s；并控制片状构件外表面温度低于废气中至少部分蒸气组分的露点温度，其温差足以使得废气中的至少部分蒸气凝结成液滴，通过对废气进行冷却使得废气中的至少部分蒸气凝结成液滴，废气中的气态污染物吸附在所述液滴上并随所述液滴湿沉降在片状构件外表面。
去除湿沉降在片状构件外表面的液滴即可实现气态污染物的去除。例如可以使湿沉降在片状构件外表面的液滴滴落或流走，还可以进一步使这些液滴通过引流通道流走。在一些实施方案中，可以回收这些液滴，以便于对某些气态污染物组分进行再利用。例如可以通过引流通道收集这些液滴，或者还可以进一步将这些液滴收集到容器中，例如将这些液滴引流至容器中。
使用时，可以将本发明的气态污染物去除装置放置在废气的气流通路上，使废气流过该气态污染物去除装置。例如，如果废气通过封闭的气流通道(如烟道)，则可以将该气态污染物去除装置安插在该气流通道中间，例如可以以该气态污染物去除装置取代一部分气流通道，或者可以使该气流通道从中间截断，并分别与该气态污染物去除装置的气流入口和气流出口相连。应当理解，本发明的气态污染物去除装置也可以应用于非封闭的废气流，只要使废气流过该气态污染物去除装置即可。
冷却装置中的片状构件为至少2个，即可以是2个或更多个，例如3个、4个、5个 或更多个。
本发明的“片状构件”是指基本上为片状的构件，该构件的外表面可以具有一定的弧度或角度，例如可以经压制形成波纹形状，只要整体上大体是片状的即可。当使用本发明的装置去除废气中的气态污染物时，所述装置放置的位置应当使得平行构件基本上平行于气流走向。
本发明中所述的“基本上平行”并不排除相互平行的线和/或面上存在弧度或相对呈一定角度，仅要求形成它们之间有大致相同的距离，总的来说，“基本上平行”包括完全平行的状态和并非完全平行但基本上平行的状态，在该并非完全平行但基本上平行的状态，基本上可以获得期望的效果。具体地，术语“基本上平行”包括线和面或者面和面完全平行的状态，以及它们从完全平行状态相对移动0°至约10°-30°的情况，例如它们从完全平行状态相对移动0°至约10°-20°的情况。
片状构件之间可以通过任何可以将其固定为基本上平行的状态的方式相互连接，例如可在片状构件的边缘处通过连接件相互连接，或者可以在片状构件的板面上的任何位置处通过连接件相互连接，所述连接件可以是板状、条状、管状、柱状或任何适宜连接片状构件的形状。连接件应当不会阻挡气流流动的方向，但连接件对气流流动的扰动是允许的。
可以通过本领域已知的任何适当的方式使得片状构件外表面保持所需的温度，例如通过冷却气、冷却液或冷源与片状构件的接触或半导体制冷原理使得片状构件外表面温度低于至少部分蒸气组分的露点温度。例如，可以使废气流过片状构件一侧，而使片状构件另一侧通有冷却气或冷却液。例如，可以使片状构件四周密封，形成周向封闭的通道，废气从通道内部通过，通道外侧接冷源或冷却液。或者，例如，可以在片状构件中设置贯穿片状构件的空心管或导热实心管，空心管中可以流动冷却液，实心管可以外接冷源。冷却液是本领域公知的，例如可以是水、氟利昂、甲醇、乙醇、丙酮、氨水等液体中的任意一种或多种的混合物。冷却气例如可以是空气、烟气或其它任何气体中的一种或多种的混合物。
由于金属材料的导热能力高于非金属材料，为了保证较大的温差，以利于热泳效应的实现，所述冷却装置的片状构件优选为金属材料，例如由铝、铜和钢中的一种或几种复合制成。为了进一步提高金属构件的使用寿命，还可对金属构件作专门的防腐处理。如对钢、铜、铝等材质的金属构件作防腐材料喷涂处理或钝化处理。
在一些实施方案中，所述片状构件是半导体热电片，所述冷却装置包括两个冷端相对的半导体热电片。如图2所示，在气态污染物去除装置1中，冷却装置冷却装置包括上部半导体热电片7和下部半导体热电片10，利用上部电源6在上部半导体热电片7中接通直流电源后，形成上部热端9和上部冷端8，利用下部电源13在下部半导体热电片10中接通直流电源后，形成下部热端12和下部冷端11，废气从上部冷端8和下部冷端11之间通过。
术语“半导体热电片”也叫半导体制冷片。它是以帕尔帖效应为基础的一种制冷技术。它的简单工作原理是：当一块N型半导体材料和一块P型半导体材料联结成电偶对时，在这个电路中接通直流电流后，就能产生能量的转移，电流由N型元件流向P型元件的接头吸收热量，成为冷端；由P型元件流向N型元件的接头释放热量，成为热端。半导体制冷片冷热端的温差可以达到40～65℃之间，如果通过主动散热的方式来降低热端温度，那冷端温度也会相应的下降，从而达到更低的温度。当两个冷端相对的半导体热电片处于工作状态时，使废气流过两个半导体热电片的冷端之间的通道，废气与冷端接触并与冷端之间形成温差。
在另一些实施方案中，所述冷却装置为板式换热器或翅片管换热器，
板式换热器是用薄金属板压制成具有一定波纹形状的换热板片，然后叠装，用夹板、螺栓紧固而成的一种换热器。板片之间形成薄矩形通道，通过板片进行热量交换。工作流体在两块板片间形成的窄小而曲折的通道中流过。循环冷却水与废气分别通过相邻的两个通道，中间有一隔层板片将两者分开，并通过此板片进行换热。板式换热器间距小，行程长，利于形成较高比例的边界层空间。使用板式换热器时，换热板片构成所述的片状构件。
如图5所示。使用翅片管换热器时，翅片构成所述的片状构件，翅片外径D相应于片状构件长度。为了便于测量和计算，在使用翅片管换热器时，可以用翅片节距代表片状构件外表面之间的间距。翅片节距t优选为小于15mm，更优选为小于10mm，更优选小于9mm，更优选小于8mm，更优选为小于5mm。翅片高h优选为大于10mm，更优选为大于15mm，更优选为大于18mm。
“翅片管换热器”是本领域技术人员所熟知的。翅片管又称鳍片管或肋片管，通常由基管和其表面上增加的翅片组合而成，使得基管表面得到扩展，管内、外流体通过管壁及翅片进行热交换，由于翅片扩大了传热面积，从而提高了换热效率。基管通常为圆管，也可以是扁平管或椭圆管。翅片形状可以是任何适合的形状，翅片可以装设在管内侧和/或管外侧，取决于换热器应用的场合以及换热器基管内外的具体流体种类。翅片管换热器的基管中可通入冷却液，废气在管外翅片间流动，废气的热量经过翅片、管壁传给管内的冷却液，从而实现了翅片管内外的热量交换。
更优选地，在本发明中，所采用的翅片管换热器是翅片热管换热器。热管又称“封闭两相传热***”，即在一个封闭体系内，依靠流体的相态变化(液相变成汽相和汽相变成液相)传递热量的装置。热管由于靠工质的相变传热，具有优异的传热特性。热管的相当导热系数比铜铝高出几十甚至上百倍，因而有超导热体之称。与外形尺寸完全相同的普通翅片管换热器相比，传递相同的功率时，热管具有良好的轴向等温性，可形成更大的传热温差。典型的热管换热器由管壳、吸液芯和端盖组成，将管内抽成一定负压后充以适量的工作液体，使紧贴管内壁的吸液芯毛细多孔材料中充满液体后加以密封。管的一端为蒸发段(加热段)，另一端为冷凝段(冷却段)，根据应用需要在两段中间可布置绝热段。当热管 的一端受热时毛纫芯中的液体蒸发汽化，蒸汽在微小的压差下流向另一端放出热量凝结成液体，液体再沿多孔材料靠毛细力的作用流回蒸发段。如此循环不己，热量由热管的一端传至另—端。本发明中，优选使用分离式热管换热器。
在一些实施方案中，所述冷却装置还可以是内翅片管式换热器。内翅片管式换热器通过在换热管内扩展表面，强化管内传热的途径来提高换热器的性能，内翅片管通常采用纵向直肋。在一个优选的实施方案中，本发明的***和方法可用于汽车尾气的排气管，可选用内翅片管式换热器，例如用横截面如图10所示的花瓣型的管式换热器替代三效催化器或中段消音器到尾部消音器之间的排气管。该管式换热器的气流通道包括中心的圆柱形通道和位于圆柱形通道四周的多个尺寸相同的板状通道，所述板状通道沿圆柱形通道的中心轴方向延伸并且从圆柱通道的中心轴沿径向向外延伸，板状通道与圆柱形通道连通。每个板状通道由两个平行的板片构成，多个板状通道绕圆柱形通道周向均匀分布。该管式换热器的气流通道中心的圆柱形通道的横截面内径可以是20-60mm，优选30-50mm，更优选为40mm；板状通道外沿的直径可以是100-200mm，优选170-220mm，更优选150mm；相邻板状通道之间的夹角可以是20-40度，优选30度。使用过程中，空气掠过管式换热器外表面可实现对尾气的冷却降温。
在冷却装置外表面(在本发明中也可称为片状构件外表面)和废气之间形成温差的其它方法是本领域技术人员公知的。
当废气的气量较大时，可以在废气流动方向的横截面上，并列布置两个或更多个(例如三个、四个、五个或更多个)冷却装置(又称为一组冷却装置，其中多个冷却装置彼此隔开适当的距离)，如图3所示。考虑到一组冷却装置的效果有限，可沿着废气流动方向布置两组或更多组(例如三组、四组、五组或更多组)冷却装置，每组冷却装置位于废气流动方向的一个横截面上，相邻两组冷却装置可以顺排布置，也可以错排布置，如图4所示。
当使用多个冷却装置时，针对每个冷却装置单独计算雷诺数、边界层厚度、热泳力和粘性曳力等。
在一些实施方案中，如图6所示，可以在冷却装置2的一侧设置喷淋装置3，该喷淋装置3用于向片状构件的外表面喷淋任何适合的液体，包括水、水溶液、有机溶剂中的任意一种或多种的混合物，以对片状构件的外表面进行清洗，防止壁面结垢，同时也可以除去湿沉降到壁面上的液滴。在一些实施方案中，可以在冷却装置两侧都设置向片状构件的外表面进行喷淋的喷淋装置。该喷淋装置可以设置在气态污染物去除装置内部，也可以设置在气态污染物去除装置外部，例如可以设置在气态污染物去除装置上游的气流通道中。优选所述喷淋装置接近片状构件，以具有较好的冲洗效果。
在一些实施方案中，可以设置对废气进行预处理的装置，例如冷却装置的上游还可以设置针对废气的喷入装置，用于向废气喷入可在废气中形成蒸气的物质，以提高废气中的蒸气含量，所述喷入装置还可以用于向废气喷入酸性物质，以产生具有高露点温度的酸 雾的喷淋装置；所述喷入装置还可以用于向废气喷入氧化性物质和/或碱性物质，以对废气中的某些气态组分进行改性。所述可在废气中形成蒸气的物质、酸性物质、氧化性物质、碱性物质的说明如前所述。所述针对废气的喷入装置可以是一个或更多个喷入装置，还可以是带有两个或更多个喷嘴、且不同喷嘴可以喷入不同物质的喷入装置。所述喷入装置可用于喷入可在废气中形成蒸气的物质、酸性物质、氧化性物质、碱性物质中的任意一种、任意两种、或任意更多种。例如可以通过多个喷入装置分别喷入可在废气中形成蒸气的物质、酸性物质、氧化性物质、碱性物质中的任意一种、任意两种、或任意更多种，还可以通过带有两个或更多个喷嘴的喷入装置分别通过不同喷嘴喷入不同物质，还可以通过同一个喷入装置的同一个喷嘴喷入不同物质的混合物，条件是所述混合物中的不同物质不会发生化学反应(可以理解，例如酸性物质和碱性物质不能混合在一起通过一个喷嘴喷入)。可在废气中形成蒸气的物质、酸性物质、氧化性物质、碱性物质中的任意一种，可以任选地喷入其纯物质或溶液形式，还可以任选地以液态形式或气态形式(例如气体或蒸气形式)被喷入，例如对于水而言，可以喷入雾化的水滴，也可以喷入水蒸气。冷却装置的上游还可以设置用于对废气进行氧化处理的装置，例如光催化氧化装置。冷却装置的上游还可以设置用于对废气进行加压的装置(例如空气压缩机)。各种喷入装置、氧化处理装置、加压装置可以根据需要任选设置，例如可以都设置，也可以仅设置其中一种、两种或更多种。这些预处理装置可以设置在气态污染物去除装置内部，也可以设置在其外部，例如可以设置在气态污染物去除装置上游的气流通道中。这些预处理装置相互之间的位置没有特别限制，可以根据需要进行设置，在一种非限制性的实例中，加压装置可以设置在喷入装置和/或氧化处理装置之后。应当理解的是，为了增强预处理效果，这些预处理装置优选与冷却装置相距较远，以使废气得到充分的预处理之后，再通过冷却装置。当这些预处理装置与用于喷淋片状构件外表面的喷淋装置同时存在时，优选这些预处理装置与片状构件之间的距离大于该喷淋装置与片状构件之间的距离。
废气经过冷却装置后，逃逸的液滴可作为凝结核吸湿长大，因此，在一些实施方案中，在冷却装置之后还可以设置其它颗粒物捕集装置4，如除雾器、除尘器等，对长大的液滴再次捕集，如图7所示。所述除尘器例如可以是湿电除尘器或文丘里除尘器。该颗粒物捕集装置可以设置在气态污染物去除装置内部，也可以设置在其外部，例如可以设置在气态污染物去除装置下游的气流通道中。
在一些实施方案中，可以在冷却装置的一侧或两侧设置喷淋装置3，同时在冷却装置之后设置其它颗粒物捕集装置4，如图8所示。
在一些实施方案中，如图9所示，可以在气态污染物去除装置下部设置引流通道5，以便于使液滴流走，或者通过该引流通道5将液滴引入容器中回收。应当理解，所述引流通道可以设置于本发明所述的任何一种气态污染物去除装置中，而不限于图9中所显示的具体结构。
本发明中所述的废气可以是任何包含气态污染物的废气，例如可以是加油站排放的 含有低沸点有机物的油气，燃煤锅炉除尘脱硫后含有有机物质的高湿净烟气，天然气燃烧后的含有氮氧化物及有机组分的高湿烟气，糠醛生产车间排放的含有乙酸、糠醛组分的高湿废气，木材处理车间所排放的高湿度废气及含有挥发性有机物及酸性气体的空气等，还包括燃油交通工具(例如燃烧汽油或柴油的汽车)运行期间排放的汽车尾气。本发明的废气包括但不限于高湿度废气，特别是经过水喷淋处理后的高湿度废气。所述废气优选主要包含气态污染物，其中“主要包含”的含义是指废气中气态污染物的含量高于其他任何一类污染物(例如颗粒态污染物，即在废气中以颗粒态形式存在的污染物)的含量，或者气态污染物的含量高于所有其他类污染物含量的总和。
如废气中所含的蒸气相对浓度不够高，不能在冷却装置内快速形成液滴时，可通过预处理提高其蒸气含量，例如提高其水蒸气含量(即含湿率，例如可以通过加蒸汽，预降温，喷水等等)或者喷入酒精蒸气，再通过气态污染物去除装置。例如可以在气态污染物去除装置前增设喷嘴或喷淋装置，喷入水或乙醇或其它有机物中的一种或更多种的混合物，增加废气中蒸气含量；也可在气态污染物去除装置前增设预换热器，对废气进行预降温，提高废气的蒸气含量(包括提高废气的相对湿度或提高废气中其它蒸气的相对含量)。预换热器形式可以是任何形式的换热器，例如普通光管换热器。
本发明与常规冷凝方法、常规雾化喷淋方法的区别：
常规冷凝方法，多是利用光管换热器，废气先接触光管换热器迎风面，行程长度较短，边界层较薄，之后接触光管换热器的背尘面，通常在光管换热器的背尘面易因涡街效应形成湍流，破坏背尘面的边界层形成，所以整体来看，光管换热器外表面边界层的平均厚度较薄，蒸气类物质冷凝达到露点后主要凝结在换热器壁面上，形成珠状或膜状凝结，在换热器外难于形成有效的雾化区域，此冷凝过程只能对于达到露点温度的蒸气类物质进行捕获，不能对其他的气态污染物进行捕捉。即使个别项目使用板式换热器换热，但其设计都从换热效率角度出发，气流风速较高，一般都在10m/s以上(风速越高，边界层越薄，换热器外对流换热系数越高，换热器换热效率越高)，所形成的纳微米雾滴数量少，高流速下难于有效发挥热泳力、蒸汽压梯度力对于雾滴的捕集，对于纳微米液滴及吸附其上的其它气态污染物无明显的捕集效果。
常规雾化喷淋方法是通过各种雾化方法将液态物质喷入待净化气体中，受雾化能力及捕集能力的限制，喷入液滴粒径多在20-100微米以上(便于在后面的除雾器中捕集)，液滴的比表面积较小，气态污染物吸附到该蒸气类物质的雾滴上后，如能被其吸收，则可以进一步被吸附，如不能被其吸收，则表面吸附完成后将不再被捕获，由于喷入液滴比表面积较小，此时对其它气态污染物的捕集效率不高。通常气态污染物被捕集后，随着喷入液滴通过重力沉降，或其他惯性力方法再被除雾器收集，不存在湿沉降，特别是云内清除过程。
实施例1
油气是汽油的挥发物，通常汽油储罐排气口会有大量油气挥发，需要进行冷凝回收，最终控制其排放浓度。
汽油组分为C4～C12，其中C4～C6占比为35％，C7～C12占比为65％。在油气中C4、C5为主要成份，其中戊烷沸点36℃，异戊烷沸点28℃，常温下属于蒸气，新戊烷沸点10℃，丁烷沸点0.50℃，异丁烷沸点-11.73℃，常温下属于气体，皆为气态污染物。
之前的回收方案为用管式换热器，降温到-15℃，回收其冷凝液，但由于上述气态污染物冷凝后形成细小的颗粒物，管式换热器对于细小颗粒物的拦截能力较弱，去除效率在20％以下，如要求更高的去除效率，需要降低到更低的温度或者对油气加压，以促进起凝结。
更改其方案为：将汽油储罐所排放油气的通入气态污染物去除装置，此气态污染物去除装置形式为：多排翅片管换热器，油气在翅片管外通过，气流流速7m/s，翅片管内工质为氟利昂134A，工质温度为-15℃，翅片节距为5mm，翅片高15mm，翅片管外径55mm，翅片外表面温度低于-10℃。翅片换热前布置有喷淋装置，喷淋乙醇溶液。
换热器换走油气中部分热量，实现油气温度下降，导致其中戊烷、异戊烷、新戊烷等污染物部分凝结成雾滴，雾滴形成的同时对废气中的其余气态污染如丁烷、异丁烷进行吸附，再通过翅片管间的热泳效应，湿沉降到翅片外表面，积累到一定量后滴落，并通过排液口回收。
凝固点较低的乙醇溶液通过喷淋形成雾化，可对翅片外表面进行冲洗，强化对捕捉到的油气液滴的回收。
整体油气污染物的去除/回收效率达90％以上，回收的油气污染物可进一步溶解入汽油中再次利用。
实施例2
一家糠醛生产厂，有渣仓工艺废气3万Nm 3/h，为饱和湿气，气温80℃左右，其中含有乙酸70mg/Nm 3，糠醛70mg/Nm 3，甲醛5mg/Nm 3，SO 3 12mg/Nm 3，及少量粉尘，且带有显著酸臭味。
与渣仓排气口相连的气流通道先经过光催化氧化***，将部分气态有机物进行氧化处理，一部分气态有机物完全氧化分解为CO 2和水，其余大部分气态有机物被氧化为更高沸点的有机物，以便于被雾滴吸附。
光催化氧化***后设有多组气态污染物去除装置，形式为：翅片管换热器，翅片管为金属复合轧制，翅片节距为6mm，翅片高16mm，翅片管外径64mm，基管内走20℃循环水，翅片外表面温度约为30℃，大大低于废气的酸露点和水露点温度，气流通过气态污染物去除装置，气流流速为4m/s。
冷凝段(净烟道内)两侧还布置有喷淋装置，喷淋水溶液。
翅片管换热器换走湿烟气中部分热量，实现废气降温，其中的SO 3、乙酸和水汽冷 凝成液滴，废气中的其他气态有机污染物被液滴所吸附，液滴湿沉降到翅片管外表面，积累到一定量后滴落，有机污染物去除效率在80％以上。
实施例3
一台300MW燃煤锅炉，产生的烟气经过湿法脱硫后成为近饱和湿烟气(相对湿度95％以上)，烟气量120万m 3/h，烟温50℃左右，其中含有颗粒物2mg/Nm 3，硫酸SO 3蒸气10mg/Nm 3，挥发性有机物13mg/Nm 3，挥发性有机物主要为脂肪烃、卤代烃、芳香烃、含氧有机物等类型，气态污染物种类达100多种。
与脱硫塔相连的净烟道内设有多组气态污染物去除装置，此气态污染物去除装置形式为：金属翅片管换热器，冷却液为20℃循环水，翅片管为金属材质，翅片外表面温度约30℃左右，大大低于烟气的酸露点和水露点，气流通过气态污染物去除装置，气流流速为4m/s。
气态污染物去除装置两侧还布置有喷淋装置，喷淋水溶液。
翅片管换热器换走湿烟气中部分热量，实现湿烟气降温冷凝，形成大量液滴，其中包括硫酸雾滴和水滴，挥发性有机物被吸附到液滴表面，液滴在热泳力、蒸汽压梯度力的推动下，湿沉降到翅片管外表面，积累到一定量后滴落，实现对于废气中的硫酸蒸气和挥发性有机物的去除，去除效率分别在70％以上和80％以上。
实施例4
一台燃气锅炉，所排放的燃烧后的烟气为近饱和湿烟气(相对湿度90％以上)，烟温约80℃，其中含有NO100mg/Nm 3。
烟道内设有紫外光催化氧化装置，实现NO向NO 2及N 2O 5气态污染物(沸点更高)去除的转化，之后设气态污染物去除装置形式为：普通翅片管式换热器，翅片节距为5mm，翅片高16mm，翅片管外径64mm，翅片与烟气温差在10℃以上，烟气流速5m/s。
换热器换走湿烟气中部分热量，实现湿烟气降温水汽冷凝成液滴，液滴吸附/吸收NO 2、N 2O 5后，沉降到翅片管外表面，积累到一定量后滴落，NOx去除效率在40％以上。
气态污染物去除装置两侧还布置有喷淋水装置，喷淋水为普通工艺水，加入适量Na 2CO 3或NaOH，用于冲洗翅片管，并可提高凝结水的碱性，以利于对NO x的吸收。
气态污染物去除装置后设置除雾器，冲洗水滴、逃逸的液滴进一步被除雾器去除。
实施例5
汽车燃烧汽油后，尾气温度通常在300℃左右，相对湿度10-20％，水露点温度在50-70℃，尾气中有部分碳氢化合物组份，这部分碳氢化合物组份在高温管路中为气态，排出后与冷空气相遇凝结形成细颗粒物。难以满足国六标准关于碳氢化合物组份及颗粒物数浓度的排放要求。
选用横截面为花瓣型的管式换热器替代三效催化器或中段消音器到尾部消音器之间的排气管。该管式换热器的气流通道包括中心的圆柱形通道和位于圆柱形通道四周的多个尺寸相同的板状通道，所述板状通道沿圆柱形通道的中心轴方向延伸并且从圆柱通道的中心轴沿径向向外延伸，板状通道与圆柱形通道连通。每个板状通道由两个平行的板片构成，多个板状通道绕圆柱形通道周向均匀分布。该管式换热器的气流通道的横截面如图10所示，其中中心的圆柱形通道的横截面内径为40mm，板状通道外沿的直径为150mm，相邻板状通道之间的夹角为30度。
汽车启动后，空气掠过管式换热器外表面进行冷却降温，可实现尾气排放温度从300度降到120度以下，末端管壁温度降到40度左右，低于尾气的水露点温度及大部分碳氢化合物的沸点温度，花瓣型的管式换热器的板状通道的板片间存在边界层，水汽在边界层内凝结成雾滴后可吸附大量碳氢化合物组份，可去除尾气中的碳氢化合物组份及颗粒物数浓度，去除效率在70％左右。
应当理解的是，本发明的上述具体实施方式仅仅用于示例性说明或解释本发明的原理，而不构成对本发明的限制。因此，在不偏离本发明的精神和范围的情况下所做的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。此外，本发明所附权利要求旨在涵盖落入所附权利要求范围和边界、或者这种范围和边界的等同形式内的全部变化和修改例。

Claims (42)

  1. 去除废气中的气态污染物的方法，包括：使废气通过气态污染物去除装置，所述气态污染物去除装置包括气流通道以及布置在气流通道中的冷却装置，所述冷却装置包括至少两个片状构件，所述片状构件基本上相互平行且基本上平行于废气的流动方向，废气从相邻片状构件之间通过，废气流速不高于10m/s；片状构件外表面温度低于废气中至少部分蒸气成分的露点温度，通过对废气进行冷却使得废气中的至少部分蒸气凝结成液滴，废气中的气态污染物吸附在所述液滴上并随所述液滴湿沉降在片状构件外表面。
  2. 根据权利要求1的方法，进一步包括：回收湿沉降到片状构件外表面的液滴。
  3. 根据权利要求1或2的方法，其中所述废气的流速不高于5m/s。
  4. 根据权利要求1-3任一项的方法，其中相邻片状构件之间的间距与片状构件在气流流动方向上的长度的比值小于0.5。
  5. 根据权利要求1-4任一项的方法，其中所述废气的相对湿度大于等于60％。
  6. 根据权利要求1-5任一项的方法，其中所述冷却装置是板式换热器。
  7. 根据权利要求1-5任一项的方法，其中所述冷却装置是翅片管换热器，换热器上的翅片构成所述片状构件。
  8. 根据权利要求7的方法，其中所述翅片管换热器是翅片热管换热器。
  9. 根据权利要求6-8任一项的方法，其中所述冷却装置由金属材料制成。
  10. 根据权利要求9的方法，其中所述冷却装置中的钢、铜、铝材质的金属构件经防腐材料喷涂处理或钝化处理。
  11. 根据权利要求1-5任一项的方法，其中所述片状构件是半导体热电片，所述冷却装置包括两个冷端相对的半导体热电片，废气从两个半导体热电片的冷端之间通过。
  12. 根据权利要求1-11任一项的方法，其中在使废气通过冷却装置之前对废气进行预处理，所述预处理包括提高废气中的蒸气含量、向废气中添加酸性物质、对废气进行氧化处理、向废气中添加碱性物质、对废气进行加压中的任意一项或几项。
  13. 根据权利要求12的方法，其中所述提高废气中的蒸气含量包括向废气中喷入可在废气中形成蒸气的物质。
  14. 根据权利要求12的方法，其中所述氧化处理包括向废气中添加氧化性物质和/或使废气通过光催化氧化装置。
  15. 根据权利要求1-14任一项的方法，还包括向所述片状构件的外表面上喷淋水、水溶液、有机溶剂中的任意一种或多种的混合物。
  16. 根据权利要求1-15任一项的方法，其中所述气态污染物去除装置包括在废气流动方向的横截面上并列布置的一组冷却装置。
  17. 根据权利要求1-16任一项的方法，其中所述气态污染物去除装置包括沿废气 流动方向上布置的多组冷却装置，每组冷却装置并列布置于废气流动方向的一个横截面上。
  18. 根据权利要求17的方法，其中相邻两组冷却装置错排布置或顺排布置。
  19. 根据权利要求1-18任一项的方法，其中在所述废气通过所述冷却装置之后，利用其它颗粒物捕集装置进一步去除大粒径液滴颗粒物。
  20. 根据权利要求19的方法，其中所述其它颗粒物捕集装置是除雾器或除尘器。
  21. 根据权利要求1-19的方法，其中进一步包括使湿沉降到片状构件外表面的液滴滴落或流走。
  22. 根据权利要求21的方法，其中使湿沉降到片状构件外表面的液滴流走是通过喷淋将湿沉降到片状构件外表面的液滴冲洗脱离片状构件外表面，再通过引流通道使其流走。
  23. 去除废气中气态污染物的***，包括：供废气通过并进行处理的气态污染物去除装置，所述气态污染物去除装置包括气流通道及布置在气流通道中的冷却装置，所述冷却装置包括至少两个片状构件，所述片状构件基本上相互平行且基本上平行于气流走向。
  24. 根据权利要求23的***，其中相邻片状构件之间的间距与片状构件在气流流动方向上的长度的比值小于0.5。
  25. 根据权利要求23或24的***，其中所述冷却装置是板式换热器。
  26. 根据权利要求23或24的***，其中所述冷却装置是翅片管换热器，换热器上的翅片构成所述片状构件。
  27. 根据权利要求26的***，其中所述翅片管换热器是翅片热管换热器。
  28. 根据权利要求23-27任一项的***，所述冷却装置由金属材料制成。
  29. 根据权利要求28的***，其中所述冷却装置中的钢、铜、铝材质的金属构件经防腐材料喷涂处理或钝化处理。
  30. 根据权利要求23的***，其中所述片状构件是半导体热电片，所述冷却装置包括两个冷端相对的半导体热电片。
  31. 根据权利要求23-30任一项的***，其中在所述冷却装置的上游侧设置有喷入装置，用于向废气中喷入可在废气中形成蒸气的物质、氧化性物质、酸性物质、碱性物质中的任意一种或几种。
  32. 根据权利要求23-31任一项的***，其中在冷却装置的上游侧设置有氧化装置，用于对废气进行氧化处理。
  33. 根据权利要求32的***，其中所述氧化装置是光催化氧化装置。
  34. 根据权利要求23-33任一项的***，其中在冷却装置的上游侧设置有加压装置，用于对废气进行加压处理。
  35. 根据权利要求23-34任一项的***，其中在所述气态污染物去除装置的一侧 或两侧设置有喷淋装置，用于向所述片状构件的外表面上喷水、水溶液、有机溶剂中的一种或几种的混合物。
  36. 根据权利要求23-35任一项的***，其中所述气态污染物去除装置包括在气流通道的横截面上并列布置的一组冷却装置。
  37. 根据权利要求23-35任一项的***，其中所述气态污染物去除装置包括沿着气流通道走向上布置的多组冷却装置，每组冷却装置并列布置于气流通道的一个横截面上。
  38. 根据权利要求37的***，其中相邻两组冷却装置错排布置或顺排布置。
  39. 根据权利要求23-38任一项的***，其中冷却装置之后，设置其它颗粒物捕集装置。
  40. 根据权利要求39的***，其中所述其它颗粒物捕集装置是除雾器或除尘器。
  41. 根据权利要求23-40任一项的***，还包括引流通道，用于使液滴通过所述引流通道引出和/或回收。
  42. 根据权利要求26的***，其中所述翅片管换热器是内翅片管式换热器。
PCT/CN2021/071121 2020-01-09 2021-01-11 废气净化***及净化方法 WO2021139815A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202010022101.4 2020-01-09
CN202010022101.4A CN112642265A (zh) 2020-01-09 2020-01-09 废气净化***及净化方法

Publications (1)

Publication Number Publication Date
WO2021139815A1 true WO2021139815A1 (zh) 2021-07-15

Family

ID=75345953

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/071121 WO2021139815A1 (zh) 2020-01-09 2021-01-11 废气净化***及净化方法

Country Status (2)

Country Link
CN (1) CN112642265A (zh)
WO (1) WO2021139815A1 (zh)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113289466B (zh) * 2021-05-26 2022-02-08 杭州昂途生物科技有限公司 一种无源直饮水和空气净化集成设备
CN114607998B (zh) * 2022-04-14 2023-06-09 泸州老窖股份有限公司 蒸糠废气热能回收处理方法和用于该方法的蒸糠机***

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63107731A (ja) * 1986-10-23 1988-05-12 Shigehisa Okayama 排煙浄化装置
CN1085120A (zh) * 1992-10-07 1994-04-13 植村博信 用于冷凝和净化燃烧气的方法和烟囱
CN1632294A (zh) * 2004-12-24 2005-06-29 清华大学 一种汽车尾气可吸入颗粒物脱除装置
CN101031673A (zh) * 2004-07-23 2007-09-05 诺尔斯海德公司 用于热量回收的方法和设备
CN105920960A (zh) * 2016-06-15 2016-09-07 高境 去除气溶胶中细颗粒物的方法和***
CN206152545U (zh) * 2016-06-23 2017-05-10 李艳萍 去除气溶胶中细颗粒物的***

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5427610A (en) * 1994-05-27 1995-06-27 Nec Electronics, Inc. Photoresist solvent fume exhaust scrubber
CN101732884A (zh) * 2008-11-26 2010-06-16 华智***科技股份有限公司 具高效率降温核凝作用的冷凝装置与方法
CN102980171A (zh) * 2011-09-06 2013-03-20 陈兴元 一种燃煤锅炉烟气余热深度回收利用与烟气冷凝脱硫除尘用省煤器
US10495361B2 (en) * 2012-05-24 2019-12-03 Maxsystems, Llc Multiple panel heat exchanger
KR101751783B1 (ko) * 2015-05-18 2017-06-28 성진엔지니어링 (주) 입자성 물질과 난용성 성상물질 및 기체상 오염물질이 포함된 배기가스 처리장치
KR101702259B1 (ko) * 2016-01-11 2017-02-06 손상영 액적 생성 장치
WO2017135182A1 (en) * 2016-02-01 2017-08-10 Central Glass Company, Limited Polymer dispersed liquid crystal glass construction
CN105854483A (zh) * 2016-05-05 2016-08-17 山东大学 强化细颗粒物表面蒸汽吸附长大过程的除尘烟道及***及方法
CN109381958A (zh) * 2017-08-10 2019-02-26 北京俊懿科技有限公司 一种复合管及voc富集装置
CN107485881A (zh) * 2017-09-28 2017-12-19 清华大学 高湿烟气净化装置
KR102063748B1 (ko) * 2018-03-21 2020-01-13 주식회사 케이에프에너지 텐터 설비용 폐열 회수 및 분진 제거 장치
CN110102406B (zh) * 2019-04-02 2024-05-03 华北电力大学（保定） 一种用于团聚和捕集可凝结颗粒物的冷电极电除尘工艺

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63107731A (ja) * 1986-10-23 1988-05-12 Shigehisa Okayama 排煙浄化装置
CN1085120A (zh) * 1992-10-07 1994-04-13 植村博信 用于冷凝和净化燃烧气的方法和烟囱
CN101031673A (zh) * 2004-07-23 2007-09-05 诺尔斯海德公司 用于热量回收的方法和设备
CN1632294A (zh) * 2004-12-24 2005-06-29 清华大学 一种汽车尾气可吸入颗粒物脱除装置
CN105920960A (zh) * 2016-06-15 2016-09-07 高境 去除气溶胶中细颗粒物的方法和***
CN206152545U (zh) * 2016-06-23 2017-05-10 李艳萍 去除气溶胶中细颗粒物的***

Also Published As

Publication number Publication date
CN112642265A (zh) 2021-04-13

Similar Documents

Publication Publication Date Title
US11014033B2 (en) Method and system for removing fine particulates from aerosol
WO2021139815A1 (zh) 废气净化***及净化方法
CN108970370A (zh) 一种低成本烟气深度净化装置及其净化收水消白烟工艺
WO2013091439A1 (zh) 一种捕集电站烟气中二氧化碳的方法及其设备
WO2012106125A1 (en) Gas treatment process and system
CN109794133B (zh) 一种烟气湿式相变超净除尘与除雾消白的一体化处理方法及其装置
CN107042048B (zh) 一种重力热管式除雾方法及除雾装置
CN110124503A (zh) 一种烟气除雾除尘消白装置及工艺
CN208927905U (zh) 一种低成本烟气深度净化装置
CN111569630A (zh) 湿法脱硫***和湿法脱硫方法
CN213021041U (zh) 烧结机烟气协同处理***
CN208244444U (zh) 一种烟气综合治理装置
CN206152545U (zh) 去除气溶胶中细颗粒物的***
JP3251883B2 (ja) 排ガス脱硫方法及びその装置
CN110141928B (zh) 一种低成本船舶湿法脱硫尾气制取淡水的装置及方法
US20050022668A1 (en) Method and apparatus for removing sulfur components
CN108786423B (zh) 一种烟气综合治理方法及装置
CN206082143U (zh) 一种脱硫塔喷雾冷凝除尘装置
CN210845867U (zh) 一种医药行业有机废气处理***
CN209317425U (zh) 一种降低白烟排放量的脱硫塔
JP2007519512A (ja) 大気から水を回収するための方法および装置
CN117643783B (zh) 一种可处理低浓度高湿度有机废气的吸收净化设备
CN206688443U (zh) 一种重力热管式除雾装置
CN110645583A (zh) 一种危险废物焚烧烟气超净排放处理***及方法
CN110841439A (zh) 一种有机废气的处理***及其处理方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21738111

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21738111

Country of ref document: EP

Kind code of ref document: A1