CN116445673B - Energy-saving water-saving blast furnace gas purification method - Google Patents
Energy-saving water-saving blast furnace gas purification method Download PDFInfo
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- CN116445673B CN116445673B CN202310359525.3A CN202310359525A CN116445673B CN 116445673 B CN116445673 B CN 116445673B CN 202310359525 A CN202310359525 A CN 202310359525A CN 116445673 B CN116445673 B CN 116445673B
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- 238000000034 method Methods 0.000 title claims abstract description 25
- 238000000746 purification Methods 0.000 title claims abstract description 16
- 239000007789 gas Substances 0.000 claims abstract description 153
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 78
- 239000007788 liquid Substances 0.000 claims abstract description 55
- 239000007921 spray Substances 0.000 claims abstract description 50
- 238000001816 cooling Methods 0.000 claims abstract description 49
- 238000006298 dechlorination reaction Methods 0.000 claims abstract description 43
- 239000000428 dust Substances 0.000 claims abstract description 43
- 238000006243 chemical reaction Methods 0.000 claims abstract description 31
- 239000002699 waste material Substances 0.000 claims abstract description 30
- 230000003197 catalytic effect Effects 0.000 claims abstract description 19
- 238000006477 desulfuration reaction Methods 0.000 claims abstract description 19
- 230000023556 desulfurization Effects 0.000 claims abstract description 19
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims abstract description 15
- 239000008213 purified water Substances 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims description 21
- 230000003009 desulfurizing effect Effects 0.000 claims description 19
- 239000002826 coolant Substances 0.000 claims description 17
- 238000005507 spraying Methods 0.000 claims description 12
- 125000001741 organic sulfur group Chemical group 0.000 claims description 5
- 238000004064 recycling Methods 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 2
- 229910052739 hydrogen Inorganic materials 0.000 claims description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims 1
- 238000006124 Pilkington process Methods 0.000 claims 1
- 239000000498 cooling water Substances 0.000 abstract description 17
- 239000003034 coal gas Substances 0.000 abstract description 16
- 238000005406 washing Methods 0.000 abstract description 7
- 238000001704 evaporation Methods 0.000 abstract description 6
- 230000008020 evaporation Effects 0.000 abstract description 5
- 238000003303 reheating Methods 0.000 abstract description 5
- 239000002918 waste heat Substances 0.000 abstract description 2
- 239000002893 slag Substances 0.000 description 15
- 239000003054 catalyst Substances 0.000 description 8
- 238000007599 discharging Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 8
- 239000000460 chlorine Substances 0.000 description 7
- 238000010521 absorption reaction Methods 0.000 description 5
- 230000009471 action Effects 0.000 description 4
- 229910052801 chlorine Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000005192 partition Methods 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- -1 chlorine ions Chemical class 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- 230000005494 condensation Effects 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 239000011280 coal tar Substances 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 230000009849 deactivation Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 2
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 2
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 238000007790 scraping Methods 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical class 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 238000006056 electrooxidation reaction Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000005189 flocculation Methods 0.000 description 1
- 230000016615 flocculation Effects 0.000 description 1
- 239000003546 flue gas Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 239000002808 molecular sieve Substances 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000036284 oxygen consumption Effects 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 239000011787 zinc oxide Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
- C21B7/002—Evacuating and treating of exhaust gases
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
- C21B7/22—Dust arresters
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
- C21B2100/40—Gas purification of exhaust gases to be recirculated or used in other metallurgical processes
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
- C21B2100/40—Gas purification of exhaust gases to be recirculated or used in other metallurgical processes
- C21B2100/42—Sulphur removal
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
- C21B2100/40—Gas purification of exhaust gases to be recirculated or used in other metallurgical processes
- C21B2100/44—Removing particles, e.g. by scrubbing, dedusting
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
- C21B2100/60—Process control or energy utilisation in the manufacture of iron or steel
- C21B2100/66—Heat exchange
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treating Waste Gases (AREA)
Abstract
The invention discloses an energy-saving water-saving blast furnace gas purifying method. The invention utilizes the dechlorination and dust removal tower, the catalytic conversion tower and the desulfurization tower to purify the blast furnace gas, specifically removes chloride and dust in a water washing, cooling and condensing mode, and realizes the high-efficiency purification of the blast furnace gas after catalytic conversion and desulfurization; after the washing spray waste liquid is purified, purified water is recycled to the circulating cooling water system; the circulating cooling water is used for cooling the coal gas, and the heat pump is used for recovering the waste heat of the circulating water and is used for reheating the coal gas, so that the steam consumption and the evaporation water consumption of the system are reduced.
Description
Technical Field
The invention belongs to the technical field of blast furnace gas purification, and particularly relates to an energy-saving water-saving blast furnace gas purification system and method.
Background
Blast furnace gas is used as one of the main secondary utilization energy sources in the steel industry, and the blast furnace gas contains CO and CO 2 、N 2 、H 2 The main components of the composition also contain trace sulfide (H) 2 S、COS、CS 2 ) Chloride (HCl, NH) 4 Cl), dust, and the like.
Along with the ultra-low emission requirement of the steel industry, the source fine desulfurization treatment is required to be carried out on the blast furnace gas, and the conventional blast furnace gas fine desulfurization process generally adopts hydrolysis conversion to convert organic sulfur into hydrogen sulfide first, and then adopts adsorption or reaction to remove the hydrogen sulfide. The dry-process fine desulfurization technology is widely used in industry due to the characteristics of strong applicability, simple operation, high desulfurization efficiency and the like, but the dry-process desulfurization temperature of blast furnace gas is generally lower than the gas temperature, liquid water can be carried in the cooling process, and the liquid water not only corrodes pipelines, but also can cause the blocking, poisoning and deactivation of the catalyst.
In addition, because the temperature window of the hydrolysis reaction of the blast furnace gas is different from the temperature window of the desulfurization reaction, the temperature of the gas needs to be increased and decreased, and a large amount of energy is lost.
Disclosure of Invention
Aiming at the defects or shortcomings of the prior art, the invention provides an energy-saving water-saving blast furnace gas purifying method.
Therefore, the method provided by the invention can save energy and save water for purifying blast furnace gas, and comprises the following steps:
the blast furnace gas with the temperature of 30-150 ℃ is in countercurrent contact with spray liquid in a dechlorination and dust removal tower, and is cooled by a multi-stage condenser in the dechlorination and dust removal tower to obtain first gas after dechlorination and dust removal, wherein the temperature of the first gas is 10-20 ℃ lower than the temperature in a desulfurizing tower; wherein the condenser which is firstly contacted with the blast furnace gas is a precooler;
the first gas is heated to 60-120 ℃ by a heating device and then enters a catalytic conversion tower, and organic sulfur in the first gas is catalytically degraded to generate H-containing gas 2 S, gas; the temperature in the catalytic conversion tower is 60-120 ℃;
containing H 2 S, cooling the gas to 30-70 ℃ by a cooling device, and then feeding the cooled gas into a desulfurizing tower to obtain clean gas through desulfurization treatment; the temperature in the desulfurizing tower is 30-70 ℃;
recovering spray waste liquid in the dechlorination dust removal tower, purifying the spray waste liquid to generate water, and taking the purified water as cooling medium and H-containing water of the cooling device 2 S gas is subjected to heat exchange to recover H-containing gas 2 And (3) after the heat in the gas is used as the cooling medium of the precooler, continuously recovering the heat of the blast furnace gas, then using the heat as the heat source of the heating device to heat the first gas, and then cooling the first gas and recycling the newly generated spray waste liquid.
The preferable scheme is that the mass percentage concentration of chloride ions in the spray waste liquid is less than 1%.
Preferably, the water content of the blast furnace gas is more than or equal to 30g/m 3 。
Preferably, the temperature of the first gas is 10-50 ℃.
The preferable scheme is that the blast furnace gas is in countercurrent contact with the multi-stage spray liquid in the dechlorination dust removal tower, and the multi-stage spray liquid and the multi-stage condenser are arranged at intervals.
The preferable scheme is that the spray liquid in the dechlorination dust removing tower closest to the blast furnace gas inlet is from the spray waste liquid; the temperature of the subsequent spray liquid of the spray waste liquid is normal temperature.
Alternatively, the purification is performed by an electrolytic air process.
The preferable scheme is that the blast furnace gas is cooled by a two-stage condenser in the dechlorination dust removal tower, and the cooling medium adopted by the condenser after the precooler is chilled water.
The energy-saving and water-saving blast furnace gas purification system for realizing the method comprises a dechlorination dust removal tower, a catalytic conversion tower and a desulfurization tower;
the dechlorination dust removal tower comprises a tower body, wherein a blast furnace gas inlet and a spray waste liquid outlet are arranged at the bottom of the tower body; the top of the tower body is provided with a first coal gas outlet; the tower body is internally provided with a spray device from the bottom to the top in sequence; wherein the condenser which is firstly contacted with the blast furnace gas is a precooler;
the bottom of the catalytic conversion tower is provided with a first gas inlet, and the top of the catalytic conversion tower is provided with a gas containing H 2 S gas outlet; the bottom of the desulfurizing tower is provided with a H-containing part 2 S gas inlet, the top has purified gas outlet;
the first gas outlet is connected with the first gas inlet through a heating device;the H-containing 2 S gas outlet is connected with H-containing gas through a first cooling device 2 S gas inlet is connected;
the spray waste liquid outlet is connected with a purifying device which is connected with a first cooling device; the first cooling device is connected with the precooler, a cooling medium in the precooler and coal gas to be added in the heating device are subjected to heat exchange and then enter the second cooling device, and the second cooling device is connected with the first cooling device.
The alternative scheme is that a multi-stage spray device is arranged in the dechlorination dust removal tower, and the multi-stage spray device and the multi-stage condenser are arranged at intervals. And a spraying device in the dechlorination dust removal tower, which is nearest to the blast furnace gas inlet, is connected with a spraying waste liquid outlet. The precooler is connected with the second cooling device through a heat exchange device, and the heat exchange device is connected with the heating device through a heat pump unit. The dechlorination dedusting tower is internally provided with a two-stage condenser, and the condenser behind the precooler is connected with a chilled water unit. The purifying device adopts an electrolytic air floatation device. And the blast furnace gas inlet is connected with a TRT unit. The system comprises two sets of dechlorination and dust removal towers which are connected in parallel.
The method adopts the modes of spray absorption, phase-change condensation and demisting separation to remove chloride, dust and water in the coal gas so as to ensure the efficient and stable operation of a fine desulfurization system, and the washing liquid after dechlorination can be recycled to a circulating cooling water system after purification treatment; the deep cooling mode is adopted, so that water carried in the coal gas is effectively removed, and the problems of catalyst deactivation, poor desulfurization effect and the like caused by the water are prevented; and the waste heat in the gas is recovered later, so that the energy consumption and the evaporation water consumption of the system are reduced.
The system and the rear end of the TRT unit can be suitable for desulfurization and dechlorination integrated purification of gas at different temperatures. The invention is especially suitable for blast furnace gas with certain water content.
Drawings
FIG. 1 is a schematic diagram of an energy-saving and water-saving blast furnace gas purification system in an embodiment of the invention;
fig. 2 is a schematic structural diagram of an electrolytic air floatation device according to an embodiment of the present invention.
Detailed Description
Unless specifically stated otherwise, the terms herein are to be understood based on knowledge of one of ordinary skill in the relevant art.
The directions or orientations of the upper, lower, bottom, top, side and the like described herein are consistent with the corresponding directions or orientations in the drawings of the specification, and it is to be noted that the directions or orientations referred to in the drawings of the specification are a specific example of the present invention, and equivalent rotations and exchanges made by those skilled in the art based on the disclosure herein are within the scope of the present invention.
The invention adds cooling process on the basis of the prior art, the spray liquid used in the chlorine dust removal tower is spray liquid used in the prior art for purifying blast furnace gas, such as but not limited to water or treated industrial wastewater, and the spray liquid is used for absorbing chloride ions in the gas and removing dust in the gas; cooling means are added in the tower, so that the gas can be cooled and water carried in the gas can be condensed out. The corresponding dechlorination dedusting tower is provided with a reasonable number of condensers at reasonable positions in the existing desulfurization dedusting tower. The multistage condenser in the specific scheme can adopt the same or different structures, and specifically realizes the target cooling temperature by controlling the temperature of the cooling medium; the structure aspect can be a heat exchange pipeline structure. In the embodiment shown in fig. 1, the cooling medium of the precooler comes from the cooling medium after the use of the first cooling device, and the cooling medium of the second stage adopts chilled water, and can be supplied by a chilled water unit 27.
The reaction principle and reaction conditions involved in the catalytic degradation, desulfurization and the like of organic sulfur are all conventional in the art, and the raw materials involved in each reaction process are substances contained in the processed gas on one hand and substances added on the other hand, for example but not limited to, catalysts used in catalytic conversion towers can be selected from aluminum-based, titanium-based and noble metal catalysts and mixtures of various types, more specifically, for example, al 2 O 3 Based on, tiO 2 One or a mixture of the groups, and impregnating a certain amount of alkali metal, alkaline earth metal, transition metal or the like; the desulfurizing agent in the desulfurizing tower can be selected from ferric oxide, zinc oxide and manganese oxideA mixture of one or more of activated carbon and molecular sieves, and the like. The corresponding equipment used for carrying out the above reactions, namely catalytic converter towers and desulfurizing towers, are well known to those skilled in the relevant arts. In a specific scheme, the temperature in the catalytic conversion tower is 60-120 ℃, preferably 70-90 ℃; the temperature in the desulfurizing tower is 30-70 ℃, preferably 40-50 ℃;
in order to achieve the effect of energy and water conservation, on the basis of the scheme, the invention recovers and purifies the spraying waste liquid (the waste liquid contains condensed water in the gas) in the dechlorination and dust removal tower by controlling the temperature of the gas outlet of the dechlorination and dust removal tower, the temperature of the gas entering the catalytic tower and the temperature of the gas entering the desulfurizing tower, and the purified waste liquid is used as a cooling medium for controlling the temperature of the gas to recover energy; and the condensed water in the blast furnace gas is contained in the spray waste liquid, so that the water of the whole process is saved.
In a further proposal, the invention can be implemented aiming at blast furnace gas with certain water content, for example, the water content in the blast furnace gas is more than or equal to 30g/m 3 . In some preferred schemes, the working efficiency of the whole system can be improved by controlling the chloride ion content in the spray waste liquid through the buckle, for example, the chloride ion content in the spray waste liquid can be controlled to be less than 1% in percentage by mass of chloride ions. In some schemes, in order to improve cooling and spray adsorption effects, spraying devices and condensing devices are arranged at intervals or alternately in the dechlorination dust removal tower. In the dechlorination spray tower in the scheme shown in fig. 1, a first-stage spray device, a precooler, a second-stage spray device, a condenser and a third-stage spray device are sequentially arranged from bottom to top. Further, a demisting device is arranged at the top of the tower.
The purification purpose of the invention is that dechlorination, ammonium removal, deslagging and oil removal (such as coal tar and the like) can be performed by adopting an electrolytic air floatation method, and the electrolytic air floatation purification principle is a technology known in the art, for example, under the action of direct current, chloride ions in the sprayed waste liquid react at an anode to generate chlorine to escape: 2Cl - (aq)-2e - ＝Cl 2 (g) Reduction reactions occur at the cathode cations: o (O) 2 (g)+4H + (aq)+4e - ＝2H 2 O、4NH 4 + (aq)+4e - +_O 2 (g)＝4NH 3 (g)+2H 2 O; and meanwhile, under the actions of flocculation, coprecipitation, electrochemical oxidation, electrochemical reduction and the like generated by electrolysis, pollutants such as chloride ions, dust, oil and the like in the solution are removed, and purified water is recycled to a circulating cooling water system. The corresponding device can be an electrolytic air floatation device. The electrolytic floatation device adopts a commercial electrolytic floatation device, such as electrolytic floatation equipment CZ010 (treatment capacity 10m 3/h) which is kept in the positive environment; or the device provided by the invention, as shown in fig. 2, comprises a shell, wherein a flow inlet chamber 91, an electrolytic reaction chamber 92, a slag discharge chamber 93 and a water purifying chamber 94 are sequentially arranged in the shell along the fluid flow direction, and a gas collecting chamber is arranged at the top of the shell; the inflow chamber 91, the electrolytic reaction chamber 92, the slag discharging chamber 93 and the water purifying chamber 94 are positioned below the gas collecting chamber; electrodes (921, 922) are arranged in the electrolytic reaction chamber 92; a slag scraping machine is arranged in the gas collection chamber; the five functional chambers are separated by a partition plate;
the side wall of the inflow chamber is provided with a water inlet, a first through hole is distributed on a partition plate between the inflow chamber and the electrolytic reaction chamber and is used for enabling water to be treated to enter the electrolytic reaction chamber from the inflow chamber, the first through hole is arranged close to the bottom of the shell, and newly entered wastewater can be fully contacted with the electrode; a second through hole is formed in the partition plate area between the electrolytic reaction chamber and the gas collection chamber, and flocculated slag and gas enter the gas collection chamber through the second through hole; a slag inlet is arranged in a partition plate area between the slag discharging chamber and the gas collecting chamber, and slag materials such as flocculate and the like entering the gas collecting chamber are discharged into the slag discharging chamber through a slag scraping machine through a gate inlet and then are discharged through a slag discharging opening at the bottom of the slag discharging chamber; the electrolytic reaction chamber is communicated with the water purifying chamber through a pipeline, the pipeline penetrates through the slag discharging chamber, purified water enters the water purifying chamber from the electrolytic reaction chamber through the pipeline, and is output through a water outlet at the bottom of the water purifying chamber.
During operation, the liquid to be treated enters the electrolytic reaction chamber 92 through the inflow chamber 91, the anode adopts a titanium electrode, chlorine ions react at the anode to generate chlorine molecules and escape, the cathode adopts an oxygen consumption electrode, and hydrogen ions and ammonium ions are electrolyzed at the cathode and react with oxygen to form ammonia and water; flocs or/and oil (oil refers to coal tar) are attached to bubbles, float up to the liquid surface, are removed by a slag scraper 95, enter a slag discharging chamber 93, and are discharged through a slag discharging port; the gas is exhausted through an exhaust port in the exhaust cover plate 96; the purified water is sent to the first cooling device 5 to be used as a cooling medium, and then is continuously sent to a precooler to be used.
In a further aspect, the electrolytic air floatation device shown in fig. 2 further includes a dual-effect circulation pump 97; the double-effect circulating pump is communicated with the bottom area of the shell, and the double-effect circulating pump 97 pumps part of the treated bottom liquid to flow back, and simultaneously pumps part of the compressed air, so that the treatment efficiency of the device is improved.
Referring to FIG. 1, the purification system structure for implementing the method of the present invention comprises a dechlorination and dust removal tower 2, a catalytic conversion tower 4 and a desulfurization tower 6; wherein: the bottom of the tower body of the dechlorination dust removal tower 2 is provided with a blast furnace gas inlet and a spray waste liquid outlet; the top of the tower body is provided with a first coal gas outlet; the tower body is internally provided with a plurality of stages of condensers from bottom to top in sequence, wherein two stages of condensers are shown in fig. 1, the condenser which is firstly contacted with blast furnace gas is a precooler 23, the other condenser 24 is externally connected with a cooling medium supply device, and a chilled water unit 27 is shown in fig. 1; a first-stage or multi-stage spraying device is also arranged in the tower body; the three-stage spraying devices (22, 26) are arranged in the way shown in FIG. 1; in the system shown in FIG. 1, the three-stage spraying device and the two-stage condenser are alternately arranged; and a demisting device 25 is arranged above the last stage of spraying device in the system shown in fig. 1;
the bottom of the catalytic conversion tower 4 is provided with a first gas inlet, and the top is provided with a gas containing H 2 S gas outlet; the bottom of the desulfurizing tower 6 is provided with H-containing components 2 S gas inlet, the top has purified gas outlet;
the first gas outlet is connected with the first gas inlet through a heating device 3; containing H 2 S gas outlet is connected with H-containing gas through a first cooling device 5 2 S gas inlet is connected;
meanwhile, a purification device 9 is connected to the spray waste liquid outlet and is connected with the first cooling device 5; the first cooling device is connected with a precooler 23, a cooling medium in the precooler exchanges heat with the gas to be heated in the heating device 3 and then enters a second cooling device (such as a cold water cooling tower) 10, and the second cooling device 10 is connected with the first cooling device 5.
In some schemes, one dechlorination dedusting tower can be arranged, or two dechlorination dedusting towers are connected in parallel and are standby, and the system can continuously operate when one tower is overhauled.
When the blast furnace gas recovery device works, original blast furnace gas (or after the residual pressure of the gas is recovered through the blast furnace gas residual pressure turbine power generation device 1, the temperature of the gas is about 40-80 ℃ at the moment, the pressure is about 20 kPa), the gas firstly enters the dechlorination and dust removal tower 2, the dechlorination and dust removal tower 2 is in countercurrent contact with the gas and normal-temperature spray liquid, dust, hydrogen chloride and the like in the gas are washed and absorbed, meanwhile, a precooler 23 and a condenser 24 (chilled water at 7-12 ℃ is used as cooling medium) arranged in the tower reduce the temperature of the gas to 10-60 ℃, and at the moment, the agglomeration and the agglomeration of fine particles in the gas are promoted due to the action of phase change nucleation and are captured by a tower top demister 25; finally, the cooled, dedusted and dechlorinated coal gas enters a heating device 3 for reheating to 60-120 ℃ and then enters a catalytic conversion tower 4;
the precooler 23 in the dechlorination dedusting tower 2 adopts circulating water cooling, the cooling condenser 24 adopts the cooling water cooling, the tower bottom is provided with a washing liquid discharge port, the washing liquid is discharged at regular time, and the concentration of chloride ions in the washing liquid is controlled to be less than 1% in a specific process.
In the catalytic converter 4, the organic sulfur in the gas is converted into H under the action of the catalyst 2 S, then the gas is cooled to 30-70 ℃ by a first cooling device 5 before desulfurization and then enters a desulfurizing tower 6, H is arranged in the desulfurizing tower 6 2 S is adsorbed or reacted by a desulfurizing agent, and clean gas is sent to downstream users;
the spray waste liquid generated in the dechlorination dust removal tower 2 is sent to a purifying device such as an electrolytic air floatation device 9 to be purified, and the purified water is sent to a first cooling device 5 to be used as a cooling medium and then is continuously sent to a precooler to be used; the heat of the high-temperature gas is recovered and then subjected to heat exchange with the gas to be heated in the heating device, and the gas is sent to the second cooling device 10 for cooling after heat release or is recycled together with the newly purified spraying waste liquid.
In some cases, when multi-stage spray is provided, the spray which is first contacted with the newly entered blast furnace gas comes from the spray waste liquid, and the spray waste liquid can be fed into the primary spray device by the washing pump 21.
In a further scheme, heat exchange between a medium output by a precooler and the heating device 3 is realized through the heat pump unit 7 and the heat exchange device 8 (such as a plate heat exchanger), the precooler is connected with the second cooling device through the heat exchange device 8, the heat absorption end (evaporator) of the heat pump unit 7 is connected with the heat exchange device 8 and is used for absorbing heat of cooling water, and the hot end (condenser) of the heat pump unit 7 is connected with the heating device 3 through heat medium water and is used for reheating cooled coal gas; thereby recovering heat in the circulating cooling water, being used for reheating the coal gas, reducing the energy consumption of the system and simultaneously saving the evaporation water consumption of the cooling tower. The circulating cooling water reduces the temperature of coal gas in the dechlorination dust removing tower and the cooler before desulfurization, and meanwhile, the temperature of the circulating water is increased. In a specific embodiment, the heat pump unit 7 may use an absorption heat pump or a vapor compression heat pump. In the specific process, the temperature difference of an inlet and an outlet of the heat exchange device can be controlled to be about 5 ℃, and the temperature difference of an inlet and an outlet of the second cooling device 10 can be controlled to be about 5 ℃.
In a further scheme, referring to fig. 1, the system further comprises a cooling water tank 11 and a cooling water pump 12, wherein purified or cooled circulating water is stored in the cooling water tank 11 and is supplied to the first cooling device 5 through the cooling water pump 12 for use in a subsequent heat exchange link.
The above description of the embodiment and the accompanying drawings represent a preferred embodiment of the present invention, and can be adjusted according to flue gas parameters, construction site conditions, etc. in actual operation.
Example 1:
the embodiment adopts the system shown in fig. 1 to carry out purification treatment on the blast furnace gas after passing through the TRT unit shown in table 1; the method for detecting the gas components in the embodiment is based on the following steps: GB-T12208-2008.
After passing through a TRT unit, the blast furnace gas enters the blast furnace gas purifying system, and the gas contains Cl, dust and H 2 S, COS, and the parameters of the blast furnace gas are shown in table 1.
TABLE 1
The blast furnace gas enters a dechlorination dust removal tower (the initial spray liquid used is water), the temperature is reduced through three-stage spray liquid spraying, a precooler and a condenser, the precooler adopts circulating cooling water to reduce the temperature of the gas from 80 ℃ to about 42 ℃, the condenser adopts chilled water to reduce the temperature of the gas from 42 ℃ to about 30 ℃, the chilled water is prepared by adopting a water-cooling compression type chilled water unit, and the temperature of the chilled water is 7-12 ℃;
after the treatment of the dechlorination and dust removal tower, the content of the outlet chloride ions is 3mg/Nm 3 The removal rate reaches 95.38 percent, and the content of the outlet dust is reduced to 3mg/Nm 3 The heat exchanger parameters are shown in table 2.
TABLE 2
| Sequence number | Project | Unit (B) | Medium 1 | Medium 2 |
| 1 | Precooler | |||
| Media name | Gas (gas) | Cooling water | ||
| Medium flow rate | Nm 3 /h | 500000 | 1354.164594 | |
| Operating temperature | ℃ | 80/42 | 30/40 | |
| Thermal load | kW | 19013.82 | 15798.59 | |
| 2 | Condenser | |||
| Medium (D)Name of the name | Gas (gas) | Chilled water | ||
| Medium flow rate | Nm 3 /h | 500000 | 551.18 | |
| Operating temperature | ℃ | 42/30 | 7/12 | |
| Thermal load | kW | 19013.82 | 3215.23 | |
| Condensation water volume | kg/h | 8525 | ||
| 3 | Chilled water unit | |||
| Media name | Chilled water | Cooling water | ||
| Medium flow rate | Nm 3 /h | 551.18 | 705.51 | |
| Operating temperature | ℃ | 7/12 | 30/35 | |
| Thermal load | kW | 3215.23 | 4115.49 |
The gas after dechlorination and dust removal is heated to 80 ℃ through a heating device 3 and then enters a catalytic conversion tower 4 (the catalyst in the tower is a catalyst which is a T908 COS hydrolytic aluminum-based catalyst (northwest chemical engineering institute), the temperature control range in the tower is 75-100 ℃), and the reacted gas is cooled to 50 ℃ through a first cooling device and enters a desulfurizing tower 6; the first cooling device adopts circulating cooling water to cool the coal gas;
the heat is extracted from the cooling circulating water backwater by adopting an absorption heat pump 7 and a heat exchange device 8, and hot water at 90 ℃ is produced and is used for reheating coal gas by a heating device, and the absorption heat pump is driven by steam. The heat exchanger parameters are shown in table 3 below.
TABLE 3 Table 3
The heat pump-free type heating device 3, the heat pump unit 7 and the heat exchange device 8 are not used in the table, and steam is used for heating the first gas.
The specific structure of the steam driven heat pump unit 7 is not shown in detail in fig. 1, and the steam driven heat pump unit comprises a generator, an evaporator, a condenser and the like, wherein the input steam of the generator is connected and is the driving side of the heat pump; the evaporator is connected with the heat exchange device 8 and is a low-temperature heat source end for recovering heat in the circulating water; the absorber and the condenser are connected with the heating device 3 and are high-temperature heat source ends for heating coal gas; the generator heat load, the evaporator heat load, the absorber heat load and the condenser heat load correspond to corresponding components in the special pump system respectively.
The desulfurizing agent used in the desulfurizing tower is active carbon, and the temperature in the tower is controlled at 40-60 ℃; the results of the clean gas are shown in Table 4:
TABLE 4 Table 4
The flow of the spraying waste liquid of the dechlorination dust removing tower is about 9m 3 Delivering 3400mg/L chloride ion content to an electrolytic air floatation device, arranging 50 pairs of electrode plates side by side into one group for ensuring working efficiency, arranging two groups along the water flow direction, connecting each group together by using PP materials, treating to obtain a solution with chloride ion content less than 100mg/L, and removing effectThe rate is more than 97%, and the treated purified water is used as circulating cooling water.
Compared with a heat pump-free process, the system of the embodiment has the advantages that the dechlorination dust removal tower recovers condensation in the coal gas and performs electrolytic treatment for recycling for 8.53t; the heat pump is adopted to save 8.42t of evaporation water of the cooling tower 10; the heat pump is adopted to recycle the heat of the circulating water for heating, and the steam is saved by 8.92t compared with the direct steam heating; the economic efficiency of the system is improved, the condensed water in the coal gas is recovered, the evaporation water consumption of the cooling tower is reduced, the water is saved by 40.86 percent, the steam is saved by 43.35 percent, and the obvious energy and water saving effect is realized, and the method is shown in the following table 5.
TABLE 5
| Project | Unit (B) | Numerical value | Remarks |
| Saving evaporating water | t/h | 8.41 | |
| Recovering condensed water | t/h | 8.53 | |
| Total water saving | t/h | 16.94 | Water saving 40.86% |
| Total steam saving | t/h | 8.92 | Saving steam 43.35% |
Claims (4)
1. An energy-saving water-saving blast furnace gas purifying method is characterized by comprising the following steps:
the blast furnace gas with the temperature of 30-150 ℃ is in countercurrent contact with spray liquid in a dechlorination and dust removal tower, and is cooled by a multi-stage condenser in the dechlorination and dust removal tower to obtain first gas after dechlorination and dust removal, wherein the temperature of the first gas is 10-20 ℃ lower than the temperature in a desulfurizing tower; wherein the condenser which is firstly contacted with the blast furnace gas is a precooler; the water content of the blast furnace gas is more than or equal to 30g/m 3 The method comprises the steps of carrying out a first treatment on the surface of the The blast furnace gas is in countercurrent contact with the multi-stage spray liquid in the dechlorination dust removal tower, and the multi-stage spray liquid and the multi-stage condenser are arranged at intervals; the spray liquid in the dechlorination dust removal tower closest to the blast furnace gas inlet comes from the spray waste liquid; the temperature of the subsequent spray liquid for spraying the waste liquid is normal temperature; the blast furnace gas is cooled by a two-stage condenser in the dechlorination dust removal tower, and a cooling medium adopted by the condenser after the precooler is chilled water;
the first gas is heated to 60-120 ℃ by a heating device and then enters a catalytic conversion tower, and organic sulfur in the first gas is catalytically degraded to generate hydrogen-containing gas 2 S, gas; the temperature in the catalytic conversion tower is 60-120 ℃;
containing H 2 S, cooling the gas to 30-70 ℃ by a cooling device, and then, introducing the cooled gas into a desulfurizing tower to obtain clean gas through desulfurization treatment; the temperature in the desulfurizing tower is 30-70 ℃;
recovering spray waste liquid in the dechlorination dust removal tower, purifying the spray waste liquid to generate water, and taking the purified water as cooling medium and H-containing water of the cooling device 2 S gas is subjected to heat exchange to recover the contentH 2 And (3) after the heat in the gas is used as the cooling medium of the precooler, continuously recovering the heat of the blast furnace gas, then using the heat as the heat source of the heating device to heat the first gas, and then cooling the first gas and recycling the newly generated spray waste liquid.
2. An energy-saving water-saving blast furnace gas purification method as set forth in claim 1, wherein the chloride ion mass percentage concentration in the spray waste liquid is less than 1%.
3. An energy-saving water-saving blast furnace gas purifying method according to claim 1, wherein the temperature of the first gas is 10-50 ℃.
4. An energy-saving water-saving blast furnace gas purifying method according to claim 1, wherein said purifying adopts an electrolytic gas float method.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007045857A (en) * | 2005-08-05 | 2007-02-22 | Nippon Steel Corp | Method and apparatus for purifying gasified gas |
| CN212025276U (en) * | 2020-01-20 | 2020-11-27 | 张鑫 | Purification device, blast furnace ironmaking system and coal gas and wastewater treatment system |
| CN112831622A (en) * | 2021-01-06 | 2021-05-25 | 鞍钢股份有限公司 | Blast furnace gas cooling and dechlorinating system and method |
| CN114854456A (en) * | 2022-04-26 | 2022-08-05 | 安徽威达环保科技股份有限公司 | Low-cost blast furnace gas desulfurization method and device thereof |
| CN115820303A (en) * | 2022-11-14 | 2023-03-21 | 中冶南方都市环保工程技术股份有限公司 | Cooling dechlorination and heat recovery blast furnace gas desulfurization system and process |
-
2023
- 2023-04-06 CN CN202310359525.3A patent/CN116445673B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007045857A (en) * | 2005-08-05 | 2007-02-22 | Nippon Steel Corp | Method and apparatus for purifying gasified gas |
| CN212025276U (en) * | 2020-01-20 | 2020-11-27 | 张鑫 | Purification device, blast furnace ironmaking system and coal gas and wastewater treatment system |
| CN112831622A (en) * | 2021-01-06 | 2021-05-25 | 鞍钢股份有限公司 | Blast furnace gas cooling and dechlorinating system and method |
| CN114854456A (en) * | 2022-04-26 | 2022-08-05 | 安徽威达环保科技股份有限公司 | Low-cost blast furnace gas desulfurization method and device thereof |
| CN115820303A (en) * | 2022-11-14 | 2023-03-21 | 中冶南方都市环保工程技术股份有限公司 | Cooling dechlorination and heat recovery blast furnace gas desulfurization system and process |
Non-Patent Citations (2)
| Title |
|---|
| 协同颗粒物脱除和水分回收的电站锅炉烟气余热利用***;李斌;王金平;安连锁;;环境工程(10);第179-183页 * |
| 移动供热:钢铁企业工业废水废热回用新途径;金亚飚;;节能与环保(06);全文 * |
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