CN214971782U

CN214971782U - Efficient anti-scale and reinforced heat exchange plate type falling film evaporation system

Info

Publication number: CN214971782U
Application number: CN202120338597.6U
Authority: CN
Inventors: 褚兴全; 褚校崧
Original assignee: Shanghai Xingquan Power Co ltd
Current assignee: Shanghai Xingquan Power Co ltd
Priority date: 2021-02-06
Filing date: 2021-02-06
Publication date: 2021-12-03
Anticipated expiration: 2031-02-06

Abstract

The utility model discloses a high-efficient anti-scaling and enhancement heat transfer board formula falling liquid film evaporation system, the utility model discloses a board-like main evaporator, steam heater, the condensate water heater of anti-scaling to and not scale deposit carrier gas heater, evaporate in succession "evaporation mother liquor", stopped production that the scale deposit caused and overhauld problem, and the problem of dirt thermal resistance. Simultaneously, still adopted heat transfer plate high frequency fluctuation to strengthen heat transfer technique and carrier gas evaporation and strengthened heat transfer technique, made the utility model discloses an evaporation system work efficiency compares ordinary MVR evaporation system efficiency and exceeds 30%.

Description

Efficient anti-scale and reinforced heat exchange plate type falling film evaporation system

Technical Field

The utility model belongs to the technical field of high salt waste water evaporative concentration, concretely relates to high-efficient anti-fouling and reinforce heat transfer plate formula falling liquid film evaporation system.

Background

In industrial production, such as coal chemical industry enterprises, steel enterprises, dairy processing industries, pesticide and pharmacy enterprises, a large amount of production tail water is generated along with production, and when the salt content in discharged water exceeds 1000mg/L, the discharged water is called high-salt water. The high-salt wastewater contains a large amount of soluble inorganic salts, such as Cl-, SO2-4, Na +, Ca2+ and other ions, and also contains a part of organic pollutants. Therefore, the high salinity wastewater produced by the production process is difficult to treat. If untreated high salt water is directly discharged into natural water, river water and underground water can be polluted, and certain threats can be caused to organisms and human beings in the water. How to efficiently treat high salt-containing water is not only beneficial to the recycling of water resources and the energy conservation and emission reduction, but also can directly influence the sustainable development of ecological environment and the human health. In the past, high-salinity water is mostly sent to an evaporation pond (also called an airing pond) in the industry, and the evaporation capacity of the environment is utilized to evaporate water to dispose the high-salinity water, but with the increasingly strict environmental protection requirements of the country and various places, the problem of high-salinity water treatment and discharge is solved, and the realization of near zero emission of industrial wastewater is one of the important problems to be solved urgently in the modern coal chemical industry at present. The 'zero discharge' scheme of further recovering water and producing crystallized salt by adopting membrane concentration treatment and evaporative crystallization technology becomes a trend for solving the problem of high-salt water.

At present, the mechanical compression re-evaporation (MVR evaporation for short) technology is adopted, which utilizes a high-energy-efficiency vapor compressor to compress secondary vapor generated by an evaporation system, improves the enthalpy of the secondary vapor, and introduces the secondary vapor into an original evaporation system to be used as a heat source for recycling. The technology greatly reduces the consumption of the raw steam of the evaporator, the supplemented raw steam is only used for supplementing the heat loss of the system and the heat enthalpy required by the temperature difference of the feeding and the discharging, the energy-saving effect is equivalent to a ten-effect evaporation system, and the technology is a relatively widely and advanced evaporator technology internationally applied at present.

After the MVR evaporation system is used for treatment, a concentrated solution with higher concentration, namely 'evaporation mother liquor', is finally generated, contains high-concentration ammonia nitrogen, salts and refractory organic matters, has high viscosity, extremely poor fluidity and extremely high scaling tendency, is difficult to treat, and cannot be treated by treatment technologies such as mature wastewater treatment methods or conventional evaporation methods. The prior treatment modes of evaporating mother liquor comprise flue spraying treatment, solidification landfill treatment, special incinerator treatment and continuous evaporation concentration treatment of a heating reaction kettle. The heating reaction kettle continuous evaporation concentration treatment technology is a treatment mode widely applied in the current market from the comprehensive consideration of investment and secondary pollution reduction. But the unit volume heating area of heating reation kettle is very little, and the problem of scale deposit in addition, the evaporation thermal efficiency is very low, can't in time effectual processing MVR evaporation mother liquor, causes the deposit volume increase of evaporation mother liquor or adopts the processing mode that has the secondary pollution problem to deal with.

And whether the membrane separation technology or the thermal evaporation technology exists the outstanding problems of high investment, high consumption and high energy consumption, and the economic cost of high-salt water treatment is huge. In short, the current method for solving the problem of high brine discharge mainly trades more energy consumption for pollutant emission reduction. Therefore, the high brine treatment system can be really operated, and the operation cost thereof must be considered. The data show that the treatment is carried out for 1m according to the characteristics of high and low salinity³The comprehensive cost of the high-salt water is about 5-20 yuan.

SUMMERY OF THE UTILITY MODEL

The utility model aims at the not enough in the above-mentioned current concentrated mother liquor technique, provide one kind can overcome evaporation mother liquor mobility poor with very easily scale deposit, and the problem that evaporation efficiency is low, accomplish in succession high-efficiently will evaporate the high-efficient anti-scaling and the enhancement heat transfer board formula falling liquid film evaporation system of the disposable dry moisture content that is fit for the combustion processing of mother liquor.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a high-efficiency anti-scaling and heat exchange plate-enhanced falling film evaporation system comprises a shell, wherein a stock solution inlet is formed in the shell, a left cavity and a right cavity are arranged in the shell in parallel, a preheating material distributing and spraying pipe connected with the stock solution inlet is arranged in the left cavity, and a condensation water heater and a secondary steam heater are arranged below the preheating material distributing and spraying pipe in parallel; the condensed water heater comprises a plurality of groups of condensed water heater heat exchange plates, and two ends of each condensed water heater heat exchange plate are respectively connected with an inlet of the condensed water heater and an outlet of the condensed water heater; the secondary steam heater comprises a plurality of groups of secondary steam heat exchange plate pieces, and two ends of each secondary steam heat exchange plate piece are respectively connected with an inlet of the secondary steam heater and an outlet of the secondary steam heater; the outlet of the secondary steam heater is connected with the inlet of the condensed water heater through a condensed water pump; a steam-water separator is arranged above the preheating material sprinkling pipe, the top of the steam-water separator is connected with a non-condensable gas outlet, and the bottom of the steam-water separator is connected with an outlet of a condensed water heater through a condensed water return pipe;

a hot material sprinkling pipe connected with a stock solution inlet is arranged in the right cavity, and a main evaporator is arranged below the hot material sprinkling pipe; the main evaporator comprises a plurality of groups of main heat exchange plates, and two ends of each main heat exchange plate are respectively connected with a main heat source through a main heat source inlet header and a main heat source outlet header; an evaporation hopper is arranged below the main heat exchange plate, and is connected with a hot material sprinkling pipe through a hot material circulating pipe with a hot material circulating pump; the lower parts of the secondary steam heater and the condensed water heater are communicated with the evaporation hopper through the preheating hopper.

Preferably, a group of liquid distributors are respectively arranged in the left cavity and the right cavity of the shell, the group of liquid distributors are arranged between the preheating material sprinkling pipe and the secondary steam heat exchange plate and the condensation water heater heat exchange plate, and the other group of liquid distributors are arranged between the hot material sprinkling pipe and the main heat exchange plate; the liquid distributors in the left cavity and the right cavity are respectively connected with the preheating material sprinkling pipe and the hot material sprinkling pipe through the liquid material distribution ultrasonic homogenizer.

Preferably, the liquid distributor comprises a liquid distribution rack, a liquid distributor flume and a liquid distributor vent groove; the bottom of the liquid distribution frame is provided with a plurality of liquid distributor liquid grooves with inverted triangular three-dimensional structures in parallel, the side edges of the bottom of the liquid distributor liquid grooves are in contact with the two sides of the main heat exchange plate, and liquid distributor vent grooves are formed in the liquid distribution frame among the liquid distributor liquid grooves.

Preferably, a carrier gas enhanced heat exchange system is arranged below the plurality of groups of main heat exchange plates, and comprises a carrier gas distributor, a carrier gas inlet pipe, a carrier gas heater and an air inlet pipe; the air inlet pipe is provided with an air filter and is connected with the carrier gas inlet pipe through the carrier gas heater, the carrier gas inlet pipe is arranged below the carrier gas distributor, the carrier gas in the carrier gas inlet pipe uniformly rises through the carrier gas distributor, saturated steam between each main heat exchange plate is rapidly taken away, the heat transfer temperature difference and the pressure difference of the liquid film are increased, and the heat exchange effect is enhanced.

Preferably, the solar heating device further comprises a solar heater, the solar heater is arranged on an air inlet pipe, the air inlet pipe is respectively connected with the carrier gas inlet pipe and the carrier gas heater through a carrier gas three-way valve, and the carrier gas inlet pipe is respectively connected with the carrier gas heater and the air inlet pipe through a carrier gas automatic valve.

Preferably, a carrier gas evaporation system is arranged above the main heat exchange plate and comprises an evaporation chamber, a secondary steam outlet, a secondary steam pipeline and a secondary steam fan; the evaporation chamber sets up in right cavity, the secondary steam pipeline sets up in left cavity, the top installation secondary steam fan of secondary steam pipeline, the bottom and the entry UNICOM of secondary steam heater of secondary steam pipeline, the evaporation chamber in the right cavity passes through the secondary steam pipeline in the left cavity of secondary steam outlet UNICOM.

Preferably, ultrasonic descaling equipment is arranged in the shell and comprises an ultrasonic generator, an ultrasonic transducer and an ultrasonic vibration transmission rod, the ultrasonic vibration transmission rod is connected with each heat exchange plate, the ultrasonic generator is connected with the ultrasonic vibration transmission rod through the ultrasonic transducer to transmit variable-frequency high-frequency low-amplitude energy waves generated by the ultrasonic transducer to each main heat exchange plate, so that metal particles of the main heat exchange plates continuously generate high-frequency low-amplitude fluctuation, and ultrasonic descaling is realized.

Preferably, a mechanical scraper type descaling device is arranged in the shell, and comprises a scraper, a bracket and a driving mechanism; the scraper blades are arranged between every two heat exchange plate sheets, the driving mechanism is connected with the scraper blades through the support, and the driving mechanism controls the support to drive the scraper blades to move, so that mechanical scraper blade type descaling is realized.

Preferably, the bottom of evaporation hopper adopts the toper structure, the concentrate export is connected to toper structure bottom, be equipped with anti-sticking device on the evaporation hopper, make the inseparable firm bonding of material on the wall, be equipped with rotatory scraper blade material conveyer in the concentrate export.

Compared with the prior art, the utility model beneficial effect as follows:

(1) the main evaporator, the steam heater and the condensed water heater adopt a plate-type falling film evaporation mode, and have the advantages of large evaporation free surface, high heat transfer coefficient, large water evaporation capacity, low steam consumption, large backwater ratio, high secondary steam condensed water quality, light equipment weight of unit heat exchange surface, easy self-falling of scale (scab), no influence on heat transfer area due to scale (scab) on the heat exchange surface, no problem that the tubular evaporator blocks up tubes, and the like.

(2) The main evaporator, the steam heater and the condensed water heater are arranged side by side, the shell of the heat exchanger can serve as a shell of skid-mounted equipment, an independent skid-mounted equipment shell is not needed, the structure is compact, and the occupied space of a unit heat exchange area is smaller than that of a shell-and-tube evaporator of the same evaporator by more than 3 times.

(3) 1 set of ultrasonic scale prevention and removal device can be shared in small-sized evaporation, and the investment cost is saved on the basis of ensuring the application effect.

(4) Metal particles on heat exchange plates of the main evaporator, the steam heater and the condensed water heater have high-frequency low-amplitude elliptical fluctuation, so that the heat exchange plate has a good scale prevention and removal effect, a good enhanced heat exchange effect and small total heat source loss of an evaporation system.

(5) And the carrier gas heater adopts a low surface energy technology, so that effective heat exchange can be ensured in high-concentration materials without bonding the materials.

(6) The carrier gas evaporation system is arranged, boiling heat exchange carried out on the heating wall surface is effectively changed into evaporation heat exchange on a gas-liquid phase interface, a heat transfer boundary layer is damaged, heat transfer is further strengthened, and the possibility of overheating and scabbing of materials on the heating wall surface is reduced and inhibited.

(7) The liquid distributor adopts an ultrasonic material homogenizing technology, so that not only can the scaling of a material tank be prevented, but also the membrane can be effectively and uniformly distributed, and the foundation is laid for efficient heat exchange.

(8) The evaporation hopper is provided with the wall adhesion preventing device, the scraper device and the material conveying device, so that the evaporated materials in various forms are smoothly discharged, and the normal operation of an evaporation system is ensured.

(9) And the steam-water separation system adopts a needle-shaped wheel hypergravity separation technology, and the device has small volume and high separation efficiency.

(10) The utility model discloses evaporation equipment is fit for using in the serious high salt waste water evaporation of scale deposit and material evaporation field.

The utility model discloses a board-like main evaporator, steam heater, the condensate water heater of anti-scaling to and not scale deposit carrier gas heater, evaporate in succession "evaporation mother liquor", stopped production that the scale deposit caused and overhauld problem, and the problem of dirt thermal resistance has been stopped. Simultaneously, still adopted heat transfer plate high frequency fluctuation to strengthen heat transfer technique and carrier gas evaporation and strengthened heat transfer technique, made the utility model discloses an evaporation system work efficiency compares ordinary MVR evaporation system efficiency and exceeds 30%. The drying degree of the evaporation mother liquor processed by the evaporation system can be manually controlled, namely the evaporation mother liquor can be evaporated to the required drying degree, so as to facilitate the subsequent further processing; for example, the 'evaporation mother liquor' with higher combustion heat value can be treated to the water content below 30 percent and then put into an incinerator for treatment, and the heat emitted during combustion is larger than the absorbed heat, so that the harm of 'high-concentration concentrated liquor' is thoroughly eliminated; for another example, the utility model discloses evaporating system can once only evaporate to below the water content 10% with "evaporation mother liquor" that has the high-risk nature, then carries out ultra-high temperature crystallization again and handles to thoroughly eliminate the secondary pollution problem.

Drawings

FIG. 1 is a schematic structural view of a high-efficiency anti-scaling and enhanced heat exchange plate-type falling film evaporation system provided by the present invention;

fig. 2 is a schematic diagram of a liquid distributor principle of a high-efficiency anti-scaling and reinforced heat exchange plate type falling film evaporation system provided by the utility model.

Reference numbers in the figures:

1. a primary evaporator; 1.1, a main heat source inlet header; 1.2, a main heat source outlet header; 1.3, main heat exchange plates; 1.4, a main heat source; 2. a secondary steam heater; 2.1, a secondary steam heater inlet; 2.2, a secondary steam heater outlet; 2.3, secondary steam heat exchange plates; 2.4, a condensate pump; 3. a condensed water heater; 3.1, a condensed water heater inlet; 3.2, outlet of the condensed water heater; 3.3, heat exchange plates of the condensed water heater; 4. a condensate return pipe; 5. An ultrasonic transducer; 6. an ultrasonic vibration transmission rod; 7. a stock solution inlet; 7.1, preheating a material distribution and sprinkling pipe; 8. A liquid distributor; 8.1, a liquid distributor liquid tank; 8.2, a liquid distributor vent groove; 9. a steam-water separator; 10. a housing; 11. a noncondensable gas outlet; 12. preheating a hopper; 13. a secondary steam fan; 14. a secondary steam outlet; 15. an evaporation chamber; 16. a demister; 17. a hot material separate spraying pipe; 18. liquid distribution ultrasonic homogenizer; 19. a hot material circulating pipe; 20. a hot material circulating pump; 21. a carrier gas distributor; 22. a carrier gas inlet tube; 23. a carrier gas automatic valve; 24. rotating the scraper conveyor; 25. a carrier gas heater; 26. an anti-sticking device; 27. a carrier gas three-way valve; 28. a solar heater; 29. an air filter; 30. an air inlet pipe; 31. a high-frequency vibrator; 32. an evaporation hopper; 33. and (6) a concentrated solution outlet.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.

As shown in fig. 1, the high-efficiency anti-scaling and heat exchange plate-enhanced falling film evaporation system provided by the present invention comprises a casing 10, wherein a stock solution inlet 7 is provided on the casing 10, a left cavity and a right cavity are provided in the casing 10 in parallel, a preheating material separate shower pipe 7.1 connected to the stock solution inlet 7 is provided in the left cavity, and a condensate water heater 3 and a secondary steam heater 2 are provided in parallel below the preheating material separate shower pipe 7.1; the condensed water heater 3 comprises a plurality of groups of condensed water heater heat exchange plate pieces 3.3, and two ends of each condensed water heater heat exchange plate piece 3.3 are respectively connected with a condensed water heater inlet 3.1 and a condensed water heater outlet 3.2; the secondary steam heater 2 comprises a plurality of groups of secondary steam heat exchange plate pieces 2.3, and two ends of each secondary steam heat exchange plate piece 2.3 are respectively connected with a secondary steam heater inlet 2.1 and a secondary steam heater outlet 2.2; the outlet 2.2 of the secondary steam heater is connected with the inlet 3.1 of the condensed water heater through a condensed water pump 2.4; a steam-water separator 9 is arranged above the preheating material sprinkling pipe 7.1, the top of the steam-water separator 9 is connected with a non-condensable gas outlet 11, the non-condensable gas outlet 11 is used for discharging non-condensable gas in steam in time so as to enhance the rapid heat exchange of condensed water, and the bottom of the steam-water separator 9 is connected with a condensed water heater outlet 3.2 through a condensed water return pipe 4;

a hot material spray pipe 17 connected with the stock solution inlet 7 is arranged in the right cavity, and a main evaporator 1 is arranged below the hot material spray pipe 17; the main evaporator 1 comprises a plurality of groups of main heat exchange plate sheets 1.3, and two ends of each main heat exchange plate sheet 1.3 are respectively connected with a main heat source 1.4 through a main heat source inlet header 1.1 and a main heat source outlet header 1.2; an evaporation hopper 32 is arranged below the main heat exchange plate 1.3, and the evaporation hopper 32 is connected with the hot material sprinkling pipe 17 through a hot material circulating pipe 19 with a hot material circulating pump 20; the lower parts of the secondary steam heater 2 and the condensed water heater 3 are communicated with the evaporation hopper 32 through the preheating hopper 12.

The utility model provides a main evaporator 1, secondary steam heater 2, condensate water heater 3 (be abbreviated as three heat exchanger once) install side by side in the cavity about casing 10, and the shell 10 of heat exchanger just can act as the shell of sled dress equipment, does not need solitary sled dress equipment shell, compact structure, and unit heat transfer area occupation of land space is than 3 times less than with evaporation buret shell type evaporimeter volume. The installation space is saved, and necessary conditions for saving descaling equipment and reducing the arrangement of system pipelines are also provided. The three heat exchangers are all corrosion-resistant metal plate heat exchangers, and the material of the heat exchange plate is determined according to the property of the evaporation material and the heat source parameter so as to meet the performance requirements of pressure, temperature, corrosion resistance and the like. The main heat exchange plate 1.3, the secondary steam heat exchange plate 2.3 and the condensed water heat exchange plate 3.3 (hereinafter referred to as heat exchange plates) are arranged in parallel in the left cavity and the right cavity, and the distance between the three heat exchange plates is not less than 30 mm.

Further, the main heat source 1.4 of the main evaporator 1 can be determined according to the conditions of the application place and the requirements of the user, and can be electric energy heating, heat transfer oil heating, solar energy heating, smoke preheating heating or MVR heating. A heat source in the main heater 1 is moved away from the plate, enters from a main heat source inlet header 1.1 and is discharged from a main heat source outlet header 1.2; the evaporated material flows from the shell side to the bottom in a thin film state.

The heat source of the secondary steam heater 2 is hot steam generated when the main evaporator 1 heats the evaporated material, the hot steam moves away from the plate side, and the preheated material moves away from the shell side.

The heat source of the condensed water heater 3 is hot condensed water generated when the secondary steam heater 2 preheats the evaporated material, the hot condensed water goes through the plate side, and the shell side goes through the preheated material.

The utility model discloses a concrete operation method can adopt following two kinds of start-up modes:

the first starting mode is as follows: the evaporated material enters from a raw material inlet 7, and as shown in the direction of a dotted line on the figure 1, the evaporated material forms a liquid film on the secondary steam heat exchange plate 2.3 and the condensed water heater heat exchange plate 3.3 through a liquid distributor liquid tank 8.1 by a preheated material spraying pipe 7.1 connected with the raw material inlet 7 and slowly flows downwards; when the evaporation system is just started, as no secondary steam and condensed water exist in the main heat exchange plate 1.3, evaporated materials flow into the preheating hopper 12 without being heated, directly enter the evaporation hopper 32 through the one-way check valve, then are sent into the hot material sprinkling pipe 17 through the hot material circulating pipe 19 by the hot material circulating pump 20, then enter the liquid distributor 8 to form a liquid film, and the liquid film flows downwards along the outer wall of the main heat exchange plate 1.3 through the liquid distributor liquid tank 8.1;

the second starting mode is as follows: as shown in the solid line direction in fig. 1, the evaporated material enters from the raw material inlet 7, the evaporated material passes through the hot material sprinkling pipe 17 connected with the raw material inlet 7 and the liquid distributor liquid tank 8.1 to form a liquid film on the main heat exchange plate 1.3 and slowly flows downwards, heat is already in the main heat exchange plate 1.3, the liquid film flowing downwards is heated, and the evaporated material is deposited in the evaporation hopper 32;

steam generated when the incoming materials are preheated on the outer walls of the secondary steam heater 2 and the condensed water heater 3 rises into the steam-water separator 9, and after the super-gravity steam-water separation, condensed water flows back to an outlet 3.2 of the condensed water heater through the condensed water return pipe 4 to be discharged; the separated non-condensable gas is discharged through a non-condensable gas outlet 11; the preheated material falls into the preheating hopper 12, and the preheated material is smoothly introduced into the evaporation hopper 32 by the vibration of the high-frequency vibrator 31 provided in the preheating hopper 12.

The utility model discloses utilize the action of gravity of solution, make solution carry out the device of cloth membrane through liquid distributor 8, form the film on the face wall of heat transfer slab, because the film thickness is little, the free surface of evaporation is big, therefore the coefficient of heat transfer of evaporimeter is high, and the ability of evaporating water is big. Compared with the common tubular falling-film evaporator, the tubular falling-film evaporator has the advantages of high heat transfer coefficient, low steam consumption, large backwater ratio, high secondary steam condensate water quality, light equipment weight of unit heat exchange surface, easy falling of scale (scab), no influence on heat transfer area due to scale (scab) on the heat exchange surface, no problem of pipe blockage of the tubular evaporator, easy equipment installation, low civil engineering cost and the like.

Example one

According to the embodiment, the incoming materials can be evaporated into the materials with different water contents at one time according to different management standards of an application site, for example, the materials can be evaporated into a dry powder state at one time, but the operation method is not economical; generally, the evaporated material is circulated for many times to carry out evaporation concentration operation, so that energy is saved. The following is a description of multiple cycle evaporation:

the bottom of evaporation hopper 32 adopts the toper structure, concentrated solution export 33 is connected to toper structure bottom, and after the material deposit after being heated and evaporating for the first time in evaporation hopper 32 the inside, carry the material again through hot material circulating pump 20 and drench the pipe 17 the inside is drenched to the hot material, and liquid distributor cistern 8.1 through liquid distributor 8 forms the liquid film on main heat exchanger plate 1.3 and slowly flows down, so repeats. When concentrated to a certain degree, is discharged through the concentrate outlet 33.

Example two

Because the liquid film is continuously evaporated in the descending process, saturated steam is filled between each main heat exchange plate 1.3, so that the heat transfer pressure difference is reduced, and the heat exchange is influenced; a small amount of inert gas is introduced between the heat exchange plates as carrier gas to form a vaporization core in the liquid phase main body, so that the boiling mechanism is changed, and the boiling heat transfer which is usually carried out on the heating wall surface can be changed into the evaporation heat transfer process on the gas-liquid phase interface. Therefore, a carrier gas enhanced heat exchange system is arranged below the groups of main heat exchange plates 1.3, and comprises a carrier gas distributor 21, a carrier gas heater 25, a carrier gas three-way valve 27, a solar heater 28, an air filter 29 and an air inlet pipe 30. The air inlet pipe 30 is provided with an air filter 29, the air inlet pipe 30 is connected with the carrier gas inlet pipe 22 through the carrier gas heater 25, the carrier gas inlet pipe 22 is arranged below the carrier gas distributor 21, the carrier gas distributor 21 is arranged below the main heat exchange plates 1.3, the carrier gas in the carrier gas inlet pipe 22 uniformly rises through the carrier gas distributor 21, saturated steam between each main heat exchange plate 1.3 is rapidly taken away, the heat transfer temperature difference and the pressure difference of the liquid film are increased, and the heat exchange effect is enhanced. In addition, the introduction of carrier gas increases the circulation speed of liquid, and strengthens the macroscopic convection between the heat exchange plates; meanwhile, the carrier gas bubbles cause transverse pulsation of liquid around the carrier gas bubbles, a heat transfer boundary layer is damaged, heat transfer is enhanced, the total heat transfer coefficient can be improved by 30-60%, the degree of superheat of the wall surface is reduced, the heat exchange efficiency is enhanced, and the possibility of overheating, scaling and scarring of the material on the heating wall surface can be reduced and inhibited.

Further, the carrier gas heater 25 employs a low surface energy treatment technique to ensure that the carrier gas heater heat exchange tubes do not adhere to material within the highly concentrated material. The solar heater adopts a straight-through vacuum tube type heater, and a plurality of solar vacuum heating tubes are connected in series or in parallel to ensure that the heated air is at a higher temperature per unit volume.

Further, the utility model discloses a carrier gas evaporation enhanced heat transfer device has two kinds of operational modes: one is a material preheating operation mode, and is automatically switched by a carrier gas automatic valve 23 and a carrier gas three-way valve 27; in the other solar heating operation mode, the solar heater 28 is arranged on the air inlet pipe 30, the air inlet pipe 30 is respectively connected with the carrier gas inlet pipe 22 and the carrier gas heater 25 through the carrier gas three-way valve 27, and the carrier gas inlet pipe 22 is respectively connected with the carrier gas heater 25 and the air inlet pipe 30 through the carrier gas automatic valve 23.

When solar heating is available, the air passing through the air filter 29 directly enters the carrier gas distributor 21 through the carrier gas three-way valve 27 and the carrier gas automatic valve 23 after passing through the solar heater 28; when the solar heating condition is not available, the air passing through the air filter 29 passes through the carrier gas three-way valve 27 and the carrier gas automatic valve 23 and directly enters the carrier gas heater 25 to absorb the heat generated after evaporating and concentrating the materials, and then enters the carrier gas distributor 21.

Because a carrier gas reinforced heat exchange system is additionally arranged, a carrier gas evaporation system is arranged above the main heat exchange plate 1.3, and comprises a demister 16, an evaporation chamber 15, a secondary steam outlet 14, a secondary steam pipeline and a secondary steam fan 13; evaporation chamber 15 sets up in right cavity, the secondary steam pipeline sets up in left cavity, secondary steam pipeline's top installation secondary steam fan 13, secondary steam pipeline's bottom and secondary steam heater entry 2.1 UNICOM, evaporation chamber 15 in the right cavity leads to the secondary steam pipeline in the left cavity through secondary steam outlet 14 UNICOM.

Further, for better carrier gas of filtering heating, the demister is installed above the hot material sprinkling pipe 17 in the right cavity, saturated steam between a plurality of groups of main heat exchange plate sheets 1.3 is taken away by the carrier gas and passes through the liquid distributor vent groove 8.2 of the liquid distributor 8, the saturated steam enters the evaporation chamber 15 after being defoamed by the demister 16, then enters the secondary steam fan 13 through the secondary steam outlet 14, and the saturated steam enters the secondary steam heater plate sheet 2.3 of the secondary steam heater 2 through the secondary steam fan 13 through the secondary steam heater inlet 2.1. At the moment, the outer wall of the secondary steam heater plate 2.3 is provided with a liquid film of the material to be preheated, saturated steam in the plate releases latent heat of vaporization through heat exchange and then becomes hot condensed water which is discharged from the outlet 2.2 of the secondary steam heater; the condensed water is input into a condensed water heater inlet 3.1 of the condensed water heater 3 through a condensed water pump 2.4, and after heat exchange is carried out between the interior of a condensed water heater plate 3.3 and a preheated material on the outer wall of the plate, the condensed water becomes low-temperature condensed water which is discharged from a condensed water heater outlet 3.2.

EXAMPLE III

The utility model discloses an operating principle is the equipment that will distribute the liquid film on the heat transfer slab and carry out the heating evaporation, so the evenly distributed of material has very big influence to its productivity and operating performance. The ideal liquid distributor can lead the material to form a stable and even liquid film on the wall surface of the heat exchange plate, if the liquid material is unevenly distributed, bias flow or channeling easily exists, the liquid film is interrupted or evaporated to dryness, and a dry path is generated, so that scaling or scabbing is caused, on one hand, the heat transfer efficiency is reduced, and on the other hand, the service life of the evaporator is influenced. In addition, because the utility model discloses in set up carrier gas vaporization system, the carrier gas will flow from bottom to top along the heat transfer board to reach evaporation chamber 15 after passing liquid distributor 8 and demister 16. Therefore, the liquid distributor 8 in the utility model has two basic functions of uniform film distribution and ventilation; in addition, the utility model discloses a target market is using in the high concentrated "evaporation mother liquor" field of high salt, consequently still needs to have fine prevention scab and scale deposit function.

Therefore, as shown in fig. 2, a group of liquid distributors 8 are respectively arranged in the left cavity and the right cavity of the shell 10, and the liquid distributors 8 are arranged into a structure of parallel pipes and grooves, and specifically comprise a liquid distribution frame, a liquid groove 8.1 of the liquid distributor and a vent groove 8.2 of the liquid distributor; the bottom of the liquid distribution frame is provided with a plurality of liquid distributor liquid grooves 8.1 with inverted triangular three-dimensional structures in parallel, the side edges of the bottoms of the liquid distributor liquid grooves 8.1 are contacted with the two sides of the main heat exchange plate pieces 1.3, and liquid distributor vent grooves 8.2 are arranged on the liquid distribution frame among the liquid distributor liquid grooves 8.1.

One group of liquid distributors 8 are arranged between the preheating material sprinkling pipe 7.1 and the secondary steam heat exchange plate 2.3 and the condensed water heater heat exchange plate 3.3, and the other group of liquid distributors 8 are arranged between the hot material sprinkling pipe 17 and the main heat exchange plate 1.3; control liquid distributor 8 in two cavities and connect respectively through liquid material distribution supersound homocline ware 18 and preheat material branch and drench pipe 7.1 and hot material branch and drench pipe 17 (the utility model discloses one set of liquid distribution supersound homocline ware 18 of two sets of liquid distributors 8 sharing of prize has saved the input quantity of ultrasonic equipment on the basis of guaranteeing the homocline effect, has practiced thrift the cost), and supersound homocline ware 18 makes the liquid distributor wholly produce high frequency fluctuation when starting, plays the effect of scale control and homocline.

Example four

Research shows that during the process of descending the liquid film along the heat exchange plate for heat exchange, a dynamic gas mold exists between the liquid and the plate, and the existence of the gas film is not beneficial to erecting heat transfer of the surface. This is because heat needs to pass through the air film before it is transferred to the primary fluid, which is less thermally conductive than the liquid, and therefore only a small portion of the heat is transferred to the primary fluid. After the air film is fused and separated from the wall surface by the continuous bubbles, new bubbles can be formed again on the wall surface, and part of heat can enter the fluid in a nucleate boiling mode. Therefore, on the basis of the above embodiments, in this embodiment, an ultrasonic descaling device is disposed in the casing 10, the ultrasonic descaling device includes an ultrasonic generator, an ultrasonic transducer 5 and an ultrasonic vibration rod 6, the ultrasonic vibration rod 6 is connected to a plurality of groups of secondary steam heater plates 2.3, a plurality of groups of condensed water heater plates 3.3 and a plurality of groups of primary heat exchange plates 1.3, the ultrasonic generator is connected to the ultrasonic vibration rod 6 through the ultrasonic transducer 5, the energy wave which is generated by the ultrasonic transducer 5 and can be frequency-converted, high frequency and low amplitude is transmitted to the upper surface of each heat exchange plate under the driving of the ultrasonic transducer 5, the wall surface of each heat exchange plate generates high frequency fluctuation, the high frequency and low amplitude fluctuation of the wall surface of the heat exchange plate generates strong disturbance between the liquid film and the heat exchange plate to form the flow of the fluctuated liquid film, and the bubbles on the heat exchange wall surface provide energy except for heat energy, small bubbles are rapidly fused and rapidly enter the fluid, so that metal particles of the heat exchange plate continuously generate high-frequency low-amplitude fluctuation, and firstly, a retention layer between a liquid film and a metal surface is broken through, the resistance of the retention layer is reduced, the liquid film is thinner and is not broken, and the heat transfer coefficient is improved; secondly, the bubbles on the heat exchange wall surface grow up rapidly to form a gas film and enter the flowing liquid film rapidly, so that the thermal resistance formed by the gas film is reduced, and the heat transfer coefficient is improved; thirdly, the high-frequency fluctuating heat exchange plate generates strong ultrasonic impact and compression on the thin liquid film, so that water molecules are separated from the liquid state to the gas state to provide energy, and the heat transfer coefficient is further improved.

The working principle of the ultrasonic descaling equipment is as follows: the motion of the heat exchange plate is represented by that surface particles of the heat exchange plate are always kept in a high-speed elliptical track state along a certain direction, and the motion ensures that any substance on the surface of the metal wall does not stay in one place but moves along a preset direction (for example, the hand feels slippery); in addition, the surface of the heat exchange plate can generate high-frequency low-amplitude pulsation, and the pulsation ensures that any substance is not bonded to a fixed place and is continuously peeled and moved. Under the condition of not serious scaling, the two energies ensure that the surface of the metal wall is not physically sticky under any condition; under the condition of very serious scale formation, the technology has very good scale resistance.

According to the size of the heat exchangers, the three heat exchangers can share one set of descaling and antiscaling device, and can also be respectively provided with independent descaling and antiscaling devices.

The heat exchange strengthening method adopted in the utility model is a mode of making the heat exchange plate generate high-frequency fluctuation. The ultrasonic transducer source which enables the heat exchange plate to generate high-frequency fluctuation adopts a magnetostrictive transducer, and has the characteristics of high Curie temperature, stable driving force, no fatigue period, strong loading capacity, wide output frequency band and the like.

EXAMPLE five

On the basis of the fifth embodiment, in the sixth embodiment, mechanical scraper descaling equipment is added in the shell 10, and when the mechanical scraper descaling equipment is applied to special environments with very high viscosity, high organic matter specific gravity and the like, the mechanical scraper descaling equipment which runs on line can be additionally arranged between every two heat exchange plates.

The mechanical scraper type descaling equipment comprises a scraper, a bracket and a driving mechanism; the scraper blades are arranged between every two heat exchange plate sheets, the driving mechanism is connected with the scraper blades through the support, and the driving mechanism controls the support to drive the scraper blades to move, so that mechanical scraper blade type descaling is realized.

The utility model can be used independently or jointly with the ultrasonic descaling equipment and the mechanical scraper descaling equipment according to the scaling characteristics of the heat exchanger; when the scale is light, or the inorganic salt as the main component or the scale is brittle and hard, the ultrasonic online scale prevention and removal device can be independently applied. When the scale is serious, or the organic salt as the main component of the scale or the viscosity of the scale is large, the mechanical scraper type online scale prevention and removal device can be independently applied. When the scale components are relatively complex and the scaling degree is severe, two online scale prevention and removal technical devices need to be applied simultaneously.

When the mechanical scraper type descaling equipment is used together with ultrasonic type descaling equipment, the mechanical scraper type descaling equipment has super strong online scale prevention and removal and heat exchange enhancement functions, and can be applied to the fields of high-salinity wastewater evaporation and material evaporation with serious scaling. In practical application, when high-viscosity 'evaporation mother liquor' is evaporated, due to the fact that the organic matter content of the evaporated liquid is high and the viscosity of the evaporated liquid is high, the ultrasonic energy wave of a single ultrasonic descaling device can hardly achieve a satisfactory effect, and the ultrasonic descaling device has the capability of continuously running when being applied to the field of processing 'evaporation mother liquor' after being combined with mechanical scraper descaling devices.

EXAMPLE six

Because the evaporation hopper 32 is a container for the evaporated material, the difference of the dryness and the humidity of the material in the evaporation hopper is very large according to different on-site evaporation standards, and the moisture content can reach about 10% -30% sometimes, at the moment, the viscosity ratio of the material is large, and the material cannot be automatically discharged by the self gravity.

In this embodiment, the anti-sticking device 26 is provided on the evaporation hopper 32, so that the material cannot be tightly and firmly adhered to the wall surface. In addition, the rotary scraper conveyor 24 is arranged in the evaporation hopper 32, and the rotary scraper conveyor 24 has the functions of rotary scraping at the interface of the evaporation hopper 32 and the concentrated solution outlet and rotary extrusion on the vertical concentrated solution discharge pipe.

Through the cooperation of antiseized device 26 and rotatory scraper blade conveying device 24 two kinds of devices use, can ensure that the material in the evaporation hopper no matter how wet degree does, all can discharge the hopper smoothly, in order to ensure the utility model discloses the normal operating of system.

Compared with the prior art, the utility model beneficial effect as follows:

Claims

1. A high-efficiency anti-scaling and heat exchange plate-enhanced falling film evaporation system comprises a shell (10), and is characterized in that a stock solution inlet (7) is formed in the shell (10), a left cavity and a right cavity are arranged in the shell (10) in parallel, a preheating material separate spraying pipe (7.1) connected with the stock solution inlet (7) is arranged in the left cavity, and a condensation water heater (3) and a secondary steam heater (2) are arranged below the preheating material separate spraying pipe (7.1) in parallel; the condensed water heater (3) comprises a plurality of groups of condensed water heater heat exchange plate sheets (3.3), and two ends of each condensed water heater heat exchange plate sheet (3.3) are respectively connected with a condensed water heater inlet (3.1) and a condensed water heater outlet (3.2); the secondary steam heater (2) comprises a plurality of groups of secondary steam heat exchange plate sheets (2.3), and two ends of each secondary steam heat exchange plate sheet (2.3) are respectively connected with an inlet (2.1) of the secondary steam heater and an outlet (2.2) of the secondary steam heater; the outlet (2.2) of the secondary steam heater is connected with the inlet (3.1) of the condensed water heater through a condensed water pump (2.4); a steam-water separator (9) is arranged above the preheating material sprinkling pipe (7.1), the top of the steam-water separator (9) is connected with a non-condensable gas outlet (11), and the bottom of the steam-water separator (9) is connected with a condensed water heater outlet (3.2) through a condensed water return pipe (4);

a hot material spray pipe (17) connected with a stock solution inlet (7) is arranged in the right cavity, and a main evaporator (1) is arranged below the hot material spray pipe (17); the main evaporator (1) comprises a plurality of groups of main heat exchange plates (1.3), and two ends of each main heat exchange plate (1.3) are respectively connected with a main heat source (1.4) through a main heat source inlet header (1.1) and a main heat source outlet header (1.2); an evaporation hopper (32) is arranged below the main heat exchange plate (1.3), and the evaporation hopper (32) is connected with a hot material sprinkling pipe (17) through a hot material circulating pipe (19) with a hot material circulating pump (20); the lower parts of the secondary steam heater (2) and the condensed water heater (3) are communicated with the evaporation hopper (32) through the preheating hopper (12).

2. The high-efficiency anti-scaling and enhanced heat exchange plate type falling film evaporation system according to claim 1, wherein a set of liquid distributors (8) are respectively arranged in the left cavity and the right cavity of the shell (10), the set of liquid distributors (8) is arranged between the preheating material distribution shower pipe (7.1) and the secondary steam heat exchange plate (2.3) and the condensation water heater heat exchange plate (3.3), and the other set of liquid distributors (8) is arranged between the hot material distribution shower pipe (17) and the main heat exchange plate (1.3); the liquid distributors (8) in the left cavity and the right cavity are respectively connected with a preheating material spray pipe (7.1) and a heating material spray pipe (17) through a liquid material distribution ultrasonic homogenizer (18).

3. A highly efficient scale-resistant and heat exchange plate falling film evaporation system according to claim 2, wherein said liquid distributor (8) comprises a liquid distribution shelf, a liquid distributor flume (8.1) and a liquid distributor aeration flume (8.2); the bottom of the liquid distribution frame is provided with a plurality of liquid distributor liquid grooves (8.1) of inverted triangular three-dimensional structures in parallel, the side edges of the bottoms of the liquid distributor liquid grooves (8.1) are in contact with the two sides of the main heat exchange plate (1.3), and liquid distributor vent grooves (8.2) are arranged on the liquid distribution frame among the liquid distributor liquid grooves (8.1).

4. The system of claim 1, wherein a carrier gas enhanced heat exchange system is arranged below the plurality of groups of main heat exchange plates (1.3), and comprises a carrier gas distributor (21), a carrier gas inlet pipe (22), a carrier gas heater (25) and an air inlet pipe (30); the air inlet pipe (30) is provided with an air filter (29), the air inlet pipe (30) is connected with a carrier gas inlet pipe (22) through a carrier gas heater (25), the carrier gas inlet pipe (22) is arranged below a carrier gas distributor (21), the carrier gas in the carrier gas inlet pipe (22) uniformly rises through the carrier gas distributor (21), saturated steam between each main heat exchange plate (1.3) is rapidly taken away, the heat transfer temperature difference and the pressure difference of a liquid film are increased, and the heat exchange effect is enhanced.

5. The high efficiency scale-resistant and heat exchange plate falling film evaporation system according to claim 4, further comprising a solar heater (28), wherein the solar heater (28) is disposed on an air inlet pipe (30), the air inlet pipe (30) is connected to the carrier gas inlet pipe (22) and the carrier gas heater (25) through a carrier gas three-way valve (27), and the carrier gas inlet pipe (22) is connected to the carrier gas heater (25) and the air inlet pipe (30) through a carrier gas automatic valve (23).

6. The system according to claim 1, wherein a carrier gas evaporation system is arranged above the main heat exchange plates (1.3), and comprises an evaporation chamber (15), a secondary steam outlet (14), a secondary steam pipeline and a secondary steam blower (13); evaporating chamber (15) set up in the right cavity, the secondary steam pipeline sets up in the left cavity, secondary steam fan (13) are installed at the top of secondary steam pipeline, the bottom and secondary steam heater entry (2.1) UNICOM of secondary steam pipeline, evaporating chamber (15) in the right cavity are through the secondary steam pipeline in the left cavity of secondary steam export (14) UNICOM.

7. The efficient scale-resistant and heat-exchange plate-type falling film evaporation system according to claim 1, wherein an ultrasonic scale removal device is arranged in the shell (10), the ultrasonic scale removal device comprises an ultrasonic generator, an ultrasonic transducer (5) and an ultrasonic vibration rod (6), the ultrasonic vibration rod (6) is connected with each heat exchange plate (1.3), the ultrasonic generator is connected with the ultrasonic vibration rod (6) through the ultrasonic transducer (5) to transmit the energy wave which is generated by the ultrasonic transducer (5) and can be in frequency conversion, high frequency and low amplitude onto each main heat exchange plate (1.3), so that the metal particles of the main heat exchange plates (1.3) continuously generate high frequency and low amplitude fluctuation, and the ultrasonic scale removal is realized.

8. The high efficiency scale-resistant and enhanced heat exchange plate falling film evaporation system according to claim 1 or 7, wherein a mechanical scraper descaling device is arranged in the shell (10), and comprises a scraper, a bracket and a driving mechanism; the scraper blades are arranged between every two heat exchange plate sheets, the driving mechanism is connected with the scraper blades through the support, and the driving mechanism controls the support to drive the scraper blades to move, so that mechanical scraper blade type descaling is realized.

9. The high efficiency scale-resistant and heat exchange plate falling film evaporation system according to claim 1, wherein the bottom of the evaporation hopper (32) is of a conical structure, the bottom of the conical structure is connected with the concentrated solution outlet (33), the evaporation hopper (32) is provided with an anti-sticking device (26) to prevent the materials from tightly and firmly adhering to the wall surface, and the concentrated solution outlet (33) is provided with a rotary scraper conveyor (24).