CN115105936B - Method and device for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas - Google Patents
Method and device for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas Download PDFInfo
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- CN115105936B CN115105936B CN202110289348.7A CN202110289348A CN115105936B CN 115105936 B CN115105936 B CN 115105936B CN 202110289348 A CN202110289348 A CN 202110289348A CN 115105936 B CN115105936 B CN 115105936B
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- 239000003546 flue gas Substances 0.000 title claims abstract description 277
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 276
- 239000012855 volatile organic compound Substances 0.000 title claims abstract description 65
- 239000012433 hydrogen halide Substances 0.000 title claims abstract description 58
- 229910000039 hydrogen halide Inorganic materials 0.000 title claims abstract description 58
- 238000000034 method Methods 0.000 title claims abstract description 43
- 230000003197 catalytic effect Effects 0.000 claims abstract description 72
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 50
- 230000003647 oxidation Effects 0.000 claims abstract description 49
- 238000006298 dechlorination reaction Methods 0.000 claims abstract description 45
- 238000006477 desulfuration reaction Methods 0.000 claims abstract description 43
- 238000006115 defluorination reaction Methods 0.000 claims abstract description 42
- 230000023556 desulfurization Effects 0.000 claims abstract description 42
- 238000006704 dehydrohalogenation reaction Methods 0.000 claims abstract description 39
- 238000010531 catalytic reduction reaction Methods 0.000 claims abstract description 35
- 238000000746 purification Methods 0.000 claims abstract description 22
- 238000010438 heat treatment Methods 0.000 claims abstract description 15
- 230000002195 synergetic effect Effects 0.000 claims abstract description 9
- 239000007789 gas Substances 0.000 claims description 33
- 239000003054 catalyst Substances 0.000 claims description 32
- 239000003638 chemical reducing agent Substances 0.000 claims description 22
- 230000008569 process Effects 0.000 claims description 20
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 13
- 239000003463 adsorbent Substances 0.000 claims description 13
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 12
- 239000000571 coke Substances 0.000 claims description 5
- 230000003009 desulfurizing effect Effects 0.000 claims description 4
- JQJCSZOEVBFDKO-UHFFFAOYSA-N lead zinc Chemical compound [Zn].[Pb] JQJCSZOEVBFDKO-UHFFFAOYSA-N 0.000 claims description 3
- 230000001502 supplementing effect Effects 0.000 claims description 3
- -1 wherein the CO Substances 0.000 claims 1
- 238000006243 chemical reaction Methods 0.000 abstract description 20
- 238000011282 treatment Methods 0.000 abstract description 9
- 230000000694 effects Effects 0.000 abstract description 5
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 239000003517 fume Substances 0.000 description 22
- 238000002485 combustion reaction Methods 0.000 description 9
- 239000000243 solution Substances 0.000 description 9
- 238000007599 discharging Methods 0.000 description 7
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 229910052717 sulfur Inorganic materials 0.000 description 5
- 239000011593 sulfur Substances 0.000 description 5
- 238000005245 sintering Methods 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 229910021529 ammonia Inorganic materials 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 230000000630 rising effect Effects 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 2
- 239000004202 carbamide Substances 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
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- 239000003344 environmental pollutant Substances 0.000 description 2
- 231100000719 pollutant Toxicity 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
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- 241001465754 Metazoa Species 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
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- 238000004458 analytical method Methods 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/75—Multi-step processes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8621—Removing nitrogen compounds
- B01D53/8625—Nitrogen oxides
- B01D53/8631—Processes characterised by a specific device
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/864—Removing carbon monoxide or hydrocarbons
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8668—Removing organic compounds not provided for in B01D53/8603 - B01D53/8665
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2258/00—Sources of waste gases
- B01D2258/02—Other waste gases
- B01D2258/0283—Flue gases
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
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- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
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Abstract
The invention provides a method and a device for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas, belonging to the technical field of environmental protection and energy utilization. According to the invention, after desulfurization treatment is carried out on metallurgical flue gas, dechlorination and defluorination are carried out to remove hydrogen halide in the flue gas, then the obtained dehydrohalogenation flue gas is subjected to heat exchange and heating to realize first-stage heating, catalytic oxidation is carried out on the heated flue gas to remove CO and VOCs, the temperature of the flue gas is raised by means of catalytic oxidation exothermic effect to realize second-stage heating, so that the flue gas temperature reaches the proper SCR reaction temperature, thereby carrying out selective catalytic reduction to purify NO x, meanwhile, the heat after the SCR reaction is recovered, the denitration flue gas obtained by the SCR reaction and the dehydrohalogenation flue gas are subjected to heat exchange, the heat required by the heat exchange of the dehydrohalogenation flue gas is reduced, and the synergistic purification of CO, VOCs, NO x and hydrogen halide in the flue gas is realized.
Description
Technical Field
The invention relates to the technical field of environmental protection and energy utilization, in particular to a method and a device for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas.
Background
In many typical metallurgical industry processes, including a number of high temperature combustion processes, the combustion is insufficient, and the fuel not pre-treated (e.g., the fossil fuel is not desulphurized) results in the production of a significant amount of nitrogen oxides (NO x), CO, VOCs and SO 2, hydrogen halide, etc. pollutants in the flue gas. For typical metallurgical flue gas, the flue gas contains a certain amount of hydrogen halide and heavy metals, such as SO 2 and NO x, which cause environmental pollution problems such as acid rain, photochemical smog and the like. The CO and the VOCs in the flue gas have certain toxicity, the direct emission can cause serious influence on the environment, and the latter can produce toxic effects on human bodies, animals, plants and the like and are also important precursors of photochemical smog. As for hydrogen halide, if the hydrogen halide is not removed, corrosion effect is generated on subsequent pipelines, and the operation cost is increased.
For removal of nitrogen oxides (NO x), the main technologies currently include activated carbon Adsorption (ACP)/Selective Catalytic Reduction (SCR), selective non-catalytic reduction (SNCR), and the like. Among them, NH 3 -SCR (ammonia selective catalytic reduction) is considered as the most effective denitration method, and is widely used because of its advantages of good removal efficiency, no by-products, no secondary pollution, and the like. In the existing NH 3 -SCR denitration reaction, the flue gas temperature is low, and a proper temperature window for catalyzing NH 3 -SCR cannot be reached, so that fuel gas is consumed to heat the flue gas, and denitration is performed after the flue gas reaches the proper temperature window, and the operation cost is increased to a certain extent.
CO generated by incomplete combustion exists in many metallurgical flue gases, and meanwhile, a part of VOCs is contained, and many enterprises directly discharge the tail gas treatment mode, so that the CO and the VOCs are discharged, and the environment pollution is caused, and meanwhile, the resource waste is caused. It is noted that the related national standard or industry standard has not formulated the emission standard of CO, so that the CO content in the atmospheric environment is continuously high, which has a great influence on the environment. And CO is taken as a highly toxic gas, and the direct emission causes pollution to the environment, so the removal of CO becomes a key ring in the emission of industrial flue gas. The metallurgical flue gas generated by many enterprises has low CO content, cannot be directly combusted, and needs auxiliary fuel addition, so that the cost is greatly increased, and the treatment of CO is particularly urgent. For direct combustion of low-concentration CO, fuel is required to be added, and high-temperature combustion radiates heat, so that serious heat loss is caused, and heat recovery is not facilitated.
Disclosure of Invention
The invention aims to provide a method and a device for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas, which can realize the cooperative purification of CO, VOCs, NOx and hydrogen halide in the metallurgical flue gas and can realize heat recovery.
In order to achieve the above object, the present invention provides the following technical solutions:
The invention provides a method for cooperatively purifying CO, VOCs, NO x and hydrogen halide in metallurgical flue gas, which comprises the following steps:
after desulfurization is carried out on metallurgical flue gas, dechlorination and defluorination are carried out on the obtained desulfurization flue gas, and dehydrohalogenation flue gas is obtained;
carrying out catalytic oxidation on the dehydrohalogenation flue gas after heat exchange and temperature rise to obtain catalytic oxidized flue gas;
Carrying out selective catalytic reduction on the flue gas after catalytic oxidation to obtain denitration flue gas;
And carrying out heat exchange on the denitration flue gas and the dehydrohalogenation flue gas, and discharging the denitration flue gas after heat exchange.
Preferably, the metallurgical fume comprises one or more of sintering fume, coke oven fume, lead-zinc fuming furnace fume and rotary kiln fume.
Preferably, the metallurgical off-gas comprises SO 2, CO, VOCs, NOx and hydrogen halide, and the concentration of SO 2 is 400-500 mg/Nm 3; the volume concentration of CO is 0.6-3%; the content of the VOCs is 50-200 mg/m 3; the content of the NO x is 200-600 mg/m 3; the hydrogen halide comprises HCl and HF, wherein the content of the HCl is 12-17 mg/m 3, and the content of the HF is 4-12 mg/m 3.
Preferably, the desulfurization method is wet stripping or dry desulfurization; the temperature of the desulfurized flue gas obtained by the wet desulfurization is 60-80 ℃, and the water vapor content is 15-20%; the temperature of the desulfurized flue gas obtained by the dry desulfurization is 130-160 ℃.
Preferably, the sulfur content in the desulfurization flue gas is less than or equal to 30mg/Nm 3, and the sulfur content in the dehydrohalogenation flue gas is 2-3 mg/Nm 3.
Preferably, the catalytic oxidation temperature is 80-200 ℃, the space velocity is 4000-8000 h -1, and the catalyst is Pt/Al 2O3.
Preferably, the temperature of the selective catalytic reduction is 200-300 ℃, the space velocity is 4000-8000 h -1, and the catalyst is V 2O5-WO3/TiO2.
The invention provides a co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas, which comprises a dechlorination defluorination tower 2, a heat exchanger 6, a catalytic tower 7, a rectifier 8 and an NH 3 -SCR reactor 10 which are sequentially connected, wherein the outlet end of the NH 3 -SCR reactor 10 is connected with the heat exchanger 6.
Preferably, a reducing agent inlet 9 is further included, said reducing agent inlet 9 being arranged on said NH 3 -SCR reactor 10.
Preferably, the device also comprises a flame arrester 3 and a variable frequency fan 5, wherein the flame arrester 3 is connected with the dechlorination defluorination tower 2; the variable frequency fan 5 is connected with the flame arrester 3.
The invention provides a method for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas, which comprises the following steps: after desulfurization is carried out on metallurgical flue gas, dechlorination and defluorination are carried out on the obtained desulfurization flue gas, and dehydrohalogenation flue gas is obtained; carrying out catalytic oxidation on the dehydrohalogenation flue gas after heat exchange and temperature rise to obtain catalytic oxidized flue gas; carrying out selective catalytic reduction on the flue gas after catalytic oxidation to obtain denitration flue gas; and carrying out heat exchange on the denitration flue gas and the dehydrohalogenation flue gas, and discharging the denitration flue gas after heat exchange.
According to the invention, after the metallurgical flue gas is subjected to desulfurization treatment, dechlorination and defluorination are carried out to remove hydrogen halide in the flue gas, then the obtained dehydrohalogenation flue gas is subjected to heat exchange and heating to realize first-stage heating, the heated flue gas is subjected to catalytic oxidation to remove CO and VOCs, the flue gas is heated by means of catalytic oxidation exothermic effect to realize second-stage heating, the flue gas temperature reaches the proper SCR reaction temperature, so that selective catalytic reduction is carried out to purify NOx, meanwhile, the heat after the SCR reaction is recovered, the denitration flue gas obtained by the SCR reaction and the dehydrohalogenation flue gas are subjected to heat exchange to reduce the heat required by the dehydrohalogenation flue gas heat exchange, and the CO-purification of CO, VOCs, NOx and hydrogen halide in the flue gas is realized while the removal of low-concentration CO is realized.
The method firstly removes the hydrogen halide, does not affect the subsequent catalytic process, and simultaneously prevents the corrosion of the pipeline; the flue gas temperature can be improved by means of the catalytic oxidation exothermic effect, so that the corresponding temperature range of NH 3 -SCR reaction is reached, a conventional low-cost SCR denitration catalyst can be adopted for subsequent denitration, the energy consumption required by flue gas reheating is avoided while the high denitration efficiency of NH 3 -SCR is ensured, meanwhile, the heat value after the denitration reaction is subjected to heat exchange, the full utilization of heat is ensured, the purification cost of flue gas is greatly reduced, and the cooperative purification of multiple pollutants is realized. The method has the advantages of simple process, low cost, good purifying effect and remarkable environmental benefit.
Drawings
FIG. 1 is a schematic diagram of a co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas, wherein the device comprises a 1-desulfurization flue gas inlet, a 2-dechlorination defluorination tower, a 3-flame arrester, a 4-blast furnace gas inlet, a 5-variable frequency fan, a 6-heat exchanger, a 7-catalytic tower, an 8-rectifier, a 9-reducer inlet, a 10-NH 3 -SCR reactor, a 11-heat exchanged flue gas outlet and temperature control detectors T0-T8.
Detailed Description
The invention provides a method for cooperatively purifying CO, VOCs, NO x and hydrogen halide in metallurgical flue gas, which comprises the following steps:
after desulfurization is carried out on metallurgical flue gas, dechlorination and defluorination are carried out on the obtained desulfurization flue gas, and dehydrohalogenation flue gas is obtained;
carrying out catalytic oxidation on the dehydrohalogenation flue gas after heat exchange and temperature rise to obtain catalytic oxidized flue gas;
Carrying out selective catalytic reduction on the flue gas after catalytic oxidation to obtain denitration flue gas;
And carrying out heat exchange on the denitration flue gas and the dehydrohalogenation flue gas, and discharging the denitration flue gas after heat exchange.
In the present invention, the required devices or reagents are commercially available products well known to those skilled in the art unless specified otherwise.
After desulfurization is carried out on metallurgical flue gas, the obtained desulfurization flue gas is subjected to dechlorination and defluorination to obtain dehydrohalogenation flue gas. In the invention, the metallurgical flue gas comprises one or more of sintering flue gas, coke oven flue gas, lead-zinc fuming furnace flue gas and rotary kiln flue gas; when the metallurgical fume is preferably selected from the above, the ratio of the metallurgical fume of different types is not particularly limited, and any ratio can be adopted. The source of the metallurgical off-gas is not particularly limited in the present invention, and may be obtained from sources well known in the art. The flow rate of the metallurgical flue gas is not particularly limited, and the metallurgical flue gas can be regulated according to the actual treatment capacity.
In the present invention, the metallurgical off-gas preferably comprises SO 2, CO, VOCs, NOx and hydrogen halide, the concentration of SO 2 preferably being 400-500 mg/Nm 3; the volume concentration of the CO is preferably 0.6-3%; the content of the VOCs is preferably 50-200 mg/m 3; the content of NO x is preferably 200-600 mg/m 3; the hydrogen halide preferably comprises HCl and HF, the content of HCl (relative to the metallurgical off-gas) preferably being 12-17 mg/m 3, and the content of HF preferably being 4-12 mg/m 3.
The flow rate of the metallurgical flue gas is not particularly limited, and the metallurgical flue gas can be regulated according to actual treatment requirements.
In the present invention, the desulfurization method is preferably wet stripping or dry desulfurization; the temperature of the desulfurized flue gas obtained by the wet desulfurization is preferably 60-80 ℃, more preferably 65-75 ℃; the water vapor content of the desulfurization flue gas obtained by the wet desulfurization is preferably 15-20%; the temperature of the desulfurized flue gas obtained by the dry desulfurization is preferably 130-160 ℃, more preferably 140-150 ℃. In the present invention, the sulfur content in the desulfurized flue gas is preferably not more than 30mg/Nm 3.
The specific process of desulfurization is not particularly limited, equipment and processes well known in the art are selected for desulfurization, so that the sulfur content in the desulfurized flue gas is less than or equal to 30mg/Nm 3, and the desulfurization is achieved.
In the invention, the desorption dechlorination adsorbent used for dechlorination and defluorination is preferably M@C-gamma-Al 2O3; the M@C-gamma-Al 2O3 is preferably an adsorbent prepared according to the method disclosed in claim 1 in patent CN107952418A ", a method for preparing an adsorbent for selectively adsorbing HF and HCl in flue gas of SO 2" (publication date is 24 of 2018, 4). The specific conditions for the dechlorination and defluorination are not particularly limited, and the dechlorination and defluorination may be performed according to a process well known in the art. In the invention, the space velocity of the dechlorination and defluorination is preferably 4000-5000 h -1, and the dosage of the dechlorination desorbent is preferably 10-20 m 3. The invention removes hydrogen halide in metallurgical flue gas through dechlorination and desulfurization. In the invention, the sulfur content in the dehydrohalogenation flue gas is 2-3 mg/Nm 3.
After dehydrohalogenation flue gas is obtained, the dehydrohalogenation flue gas is subjected to heat exchange and temperature rise, and catalytic oxidation is carried out to obtain catalytic oxidized flue gas. The invention preferably uses an external heat source to heat so as to realize heat exchange and heating of dehydrohalogenation flue gas. The external heat source used for heat exchange and temperature rising and the specific process of heat exchange and temperature rising are not particularly limited, and the dehydrohalogenation flue gas can reach the catalytic oxidation temperature by carrying out heat exchange and temperature rising according to the process known in the art. In the present invention, the temperature of the catalytic oxidation is preferably 80 to 200 ℃, more preferably 95 to 180 ℃, further preferably 120 to 160 ℃, and the space velocity is preferably 4000 to 8000h -1, more preferably 5000 to 6000h -1; the catalyst used for the catalytic oxidation is preferably Pt/Al 2O3. The present invention preferably determines the time at which the catalytic oxidation is carried out based on space velocity. The source of the Pt/Al 2O3 catalyst is not particularly limited, and commercial products well known in the art can be selected. The dosage of the catalyst is not particularly limited, and the catalyst can be adjusted according to the actual treatment capacity; the time of the catalytic oxidation is not particularly limited, and the catalytic oxidation can be adjusted according to the dosage and the space velocity of the catalyst. In the catalytic oxidation process, CO and VOCs in dehydrohalogenation flue gas are oxidized under the action of a catalyst to generate CO 2, so that the removal of CO and VOCs is realized, the temperature of the flue gas is exothermically increased, the proper NH 3 -SCR reaction temperature is reached, and the subsequent selective catalytic reduction is facilitated. In the invention, when the catalytic oxidation is completed, the temperature of the obtained flue gas cannot reach the selective catalytic reduction temperature of 200-280 ℃, and preferably, the catalytic oxidation reaction is promoted by adding CO, so that the heat released by the catalytic oxidation is increased until the temperature reaches the temperature range.
After the catalytic oxidized flue gas is obtained, the catalytic oxidized flue gas is subjected to selective catalytic reduction to obtain denitration flue gas. The selective catalytic reduction is preferably carried out under the condition of introducing ammonia gas-air mixture; the invention has no special limit to the inflow amount of the ammonia-air mixture, and can ensure that the selective catalytic reduction is smoothly carried out by adjusting according to actual requirements. In the invention, the temperature of the selective catalytic reduction is preferably 200-300 ℃, more preferably 220-280 ℃, the space velocity is preferably 4000-8000 h -1, more preferably 5000-6000 h -1, and the catalyst used in the selective catalytic reduction is preferably V 2O5-WO3/TiO2; the reducing agent used is preferably liquid ammonia or urea; the specific dosage of the reducing agent is not particularly limited, and the reducing agent can be adjusted according to actual requirements. The present invention preferably determines the time of the selective catalytic reduction based on space velocity. The source of the V 2O5-WO3/TiO2 catalyst is not particularly limited, a commercial medium-temperature V 2O5-WO3/TiO2 SCR catalyst well known in the art is selected, the dosage of the catalyst is not particularly limited, and the catalyst is adjusted according to the actual treatment capacity; the time of the selective catalytic reduction is not particularly limited, and the selective catalytic reduction can be adjusted according to the catalyst dosage and the space velocity. In the selective catalytic reduction process, NO x in the flue gas after catalytic oxidation is reduced to N 2, so that NO x is removed, and meanwhile, the selective catalytic reduction reaction releases heat, so that the temperature of the denitration flue gas is raised.
After denitration flue gas is obtained, the denitration flue gas and the dehydrohalogenation flue gas are subjected to heat exchange, and the denitration flue gas after heat exchange is discharged. The heat source of the denitration flue gas is continuously recycled to the dehydrohalogenation flue gas, so that no external heat source is needed in the heat exchange and temperature rise step of the dehydrohalogenation flue gas. The specific process of the heat exchange is not particularly limited in the present invention, and may be performed according to a process well known in the art. The invention uses the denitration flue gas containing heat to exchange heat with the dehydrohalogenation flue gas, thereby improving the temperature of the flue gas, reducing the energy consumption required by reheating the dehydrohalogenation flue gas and realizing the full utilization of heat.
In the invention, the flue gas temperature rise after the catalytic oxidation of the CO with different concentrations is calculated according to the formulas (1), (2) and (3):
Q＝n×Cp×ΔT (1)
In the formula (1), Q: heat of flue gas, KJ; n: the amount of CO substances in the flue gas, kmol; c p: specific heat capacity of flue gas, KJ/(kmol. DEG C), wherein metallurgical flue gas is calculated according to 30 KJ/(kmol. DEG C); Δt: flue gas temperature, DEG C;
Q＝V×X×ΔH (2)
In formula (2), Q: heat of flue gas, KJ; v: flue gas volume, m 3; x: the volume concentration of CO in the flue gas; Δh: the heat of combustion of CO, KJ/m 3;
2CO+O2＝2CO2 ΔH＝12644.1KJ/m3 (3)
the heat of the flue gas in the formula (1) and the formula (2) is equal, the right sides of the two formulas are formed into an equation, and the relation between the heat release of the CO combustion of different concentrations of the flue gas and the flue gas Wen Sheng T is obtained (delta H is the heat of the CO combustion, namely the heat released after the CO combustion, and delta T is the temperature of the flue gas which is increased after the CO releases heat).
As shown in fig. 1, the invention provides a co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas, which comprises a dechlorination defluorination tower 2, a heat exchanger 6, a catalytic tower 7, a rectifier 8 and an NH 3 -SCR reactor 10 which are sequentially connected, wherein the outlet end of the NH 3 -SCR reactor 10 is connected with the heat exchanger 6.
The invention provides a CO, VOCs, NOx and hydrogen halide synergistic purification device in metallurgical flue gas, which comprises a dechlorination defluorination tower 2, wherein the dechlorination defluorination tower 2 is used for dechlorination defluorination of the flue gas, and the dechlorination defluorination tower adopts three-tower adsorption, and the three towers are connected in parallel for treatment, so that the device is dual-purpose. The specific model of the dechlorination defluorination tower 2 is not particularly limited, and dechlorination defluorination towers well known in the art can be selected.
The co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas provided by the invention comprises a heat exchanger 6 connected with the dechlorination defluorination tower 2, wherein the heat exchanger 6 is used for realizing heat exchange and temperature rise of the flue gas. The specific type of the heat exchanger 6 is not particularly limited, and a heat exchanger well known in the art may be selected.
The co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas provided by the invention comprises a catalytic tower 7 connected with the heat exchanger 6, wherein the catalytic tower 7 is used for carrying out catalytic oxidation on the flue gas. The specific type of the catalytic tower 7 is not particularly limited, and a heat exchanger well known in the art may be selected.
The invention provides a device for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas, which comprises a rectifier 8 connected with a catalytic tower 7; the structure of the rectifier 8 is not particularly limited, and any rectifier capable of rectifying, which is well known in the art, may be used. The invention utilizes the rectifier 8 to convey the mixed flue gas of ammonia and air into the NH 3 -SCR reactor 10, thereby carrying out selective catalytic reduction.
The co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas provided by the invention comprises an NH 3 -SCR reactor 10 connected with a rectifier 8; the structure of the NH 3 -SCR reactor 10 is not particularly limited in the present invention, and a reactor capable of performing NH 3 -SCR reaction, which is well known in the art, may be used. The invention uses the NH 3 -SCR reactor 10 to carry out selective catalytic reduction reaction to remove NO x in the flue gas.
As an embodiment of the invention, the co-purifying device for CO, VOCs, NOx and hydrogen halide in metallurgical fume further comprises a desulfurization fume inlet 1, wherein the desulfurization fume inlet 1 is connected with the dechlorination defluorination tower 2 and is used for feeding the desulfurized metallurgical fume.
As an embodiment of the invention, the co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas further comprises a flame arrester 3, wherein the flame arrester 3 is connected with the dechlorination defluorination tower 2. The structure of the flame arrester 3 is not particularly limited, and flame arresters well known in the art can be selected. In the present invention, the flame arrestor 3 is used to prevent explosions caused by high CO content.
As an embodiment of the invention, the CO, VOCs, NOx and hydrogen halide synergistic purification device in metallurgical flue gas also comprises a blast furnace gas inlet 4, wherein the blast furnace gas inlet 4 is connected with a variable frequency fan 5 for supplementing CO flue gas.
As an embodiment of the invention, the CO, VOCs, NOx and hydrogen halide cooperative purification device in the metallurgical flue gas is an embodiment of the invention, and the CO, VOCs, NOx and hydrogen halide cooperative purification device in the metallurgical flue gas also comprises a variable frequency fan 5; the structure of the variable frequency fan 5 is not particularly limited, and a variable frequency fan well known in the art can be selected. In the invention, the variable frequency fan 5 is connected with the flame arrester 3. In the invention, the variable frequency fan 5 is used for supplementing CO smoke, whether CO is supplemented depends on whether the exothermic heat of catalytic oxidation reaches a proper NH 3 -SCR reaction temperature interval (200-280 ℃), and when the CO in the smoke subjected to catalytic oxidation is insufficient to raise the temperature to a proper temperature interval, CO is supplemented until the NH 3 -SCR reaction temperature interval is reached.
As an embodiment of the invention, the co-purification device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas further comprises a reducing agent inlet 9, wherein the reducing agent inlet 9 is arranged on the NH 3 -SCR reactor 10, and the reducing agent inlet 9 is used for introducing reducing agent so as to perform selective catalytic reduction.
As an embodiment of the invention, the co-purifying device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas further comprises a flue gas outlet 11 after heat exchange, wherein the 11-heat exchange flue gas outlet is arranged on the heat exchanger 6 and is used for discharging flue gas obtained by heat exchange.
As an embodiment of the invention, the CO-purifying device for CO, VOCs, NOx and hydrogen halide in metallurgical flue gas further comprises a plurality of temperature control detectors, as shown in fig. 1, wherein T0 detects the temperature of flue gas before entering the heat exchanger 6, T1 detects the temperature of flue gas after heat exchange, T2 and T3 detect the temperature of CO and VOCs catalyst beds, T4 detects the temperature of a pipeline before entering the NH 3 -SCR reactor 10, T5 detects the temperature of the front end of the rectifier, T6 and T7 detect the temperature of the NH 3 -SCR reactor, and T8 detects the temperature of a pipeline after entering the heat exchanger 6 after NH 3 -SCR reaction.
In the invention, the method for treating the metallurgical fume by utilizing CO, VOCs, NOx and the hydrogen halide synergistic purification device in the metallurgical fume preferably comprises the following steps of:
Introducing the desulfurized metallurgical flue gas into a dechlorination defluorination tower 2 to remove hydrogen halide and part of SO 2, introducing the obtained flue gas into a heat exchanger 6 to perform heat exchange and temperature rise after flowing through a flame arrester 3, raising the temperature of the flue gas to the catalytic oxidation temperature, sending the flue gas to a catalytic tower 7 to perform catalytic oxidation to remove CO and VOCs, raising the temperature of the obtained flue gas by heat generated in the catalytic oxidation process, mixing the heated flue gas with a reducing agent from a reducing agent inlet 9 through a rectifier 8, introducing the mixed flue gas into an NH 3 -SCR reactor 10 to perform selective catalytic reduction reaction to obtain denitration flue gas, sending the denitration flue gas into the heat exchanger 6 to perform heat exchange with the denitration flue gas, and discharging the denitration flue gas after heat exchange reaching the standard.
The technical solutions of the present invention will be clearly and completely described in the following in connection with the embodiments of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the following examples, the dechlorination defluorination adsorbent used is patent CN107952418a "a preparation method of adsorbent for selectively adsorbing HF and HCl in SO 2 flue gas", the dechlorination defluorination adsorbent Ca@ γ -Al 2O3 prepared in example 2; the preparation method comprises the steps of preparing Al (NO 3)3 solution, adding P123 into the NO 3)3 solution according to the proportion of 1.5g/L to obtain solution A, dissolving NH 4HCO3 into the mixed solution of P123 and PVP to prepare solution B, wherein the concentration of NH 4HCO3 in the solution B is 1g/L, the concentration of P123 is 1.5g/L, the concentration of PVP is 1g/L, slowly adding the solution B into the solution A according to the proportion of 1:1 by volume under vigorous stirring, adjusting the pH value to 5 by nitric acid, continuously stirring for 1.5h to obtain wet gel, aging the wet gel at room temperature for 40h, washing by absolute ethyl alcohol, drying at 60 ℃, calcining the obtained dry gel at 550 ℃ for 3h in the atmosphere of N 2, and preparing Ca@ gamma-Al 2O3 by adopting an equal volume impregnation method.
The catalyst for catalytic oxidation is commercial Pt/Al 2O3, and the catalyst for selective catalytic reduction is medium temperature V 2O5-WO3/TiO2.
In the following examples, temperatures at different locations were detected using T0 to T8 shown in fig. 1.
Example 1
The sintering flue gas (the flow rate is 50000Nm 3/h,SO2, the concentration is 400mg/Nm 3, the volume concentration of CO is 1.5%, the content of VOCs is 100mg/m 3;NOx, the content of HCL is 417mg/m 3, the content of HCL is 12mg/m 3, the content of HF is 12mg/m 3) is desulfurized by adopting a dry method to obtain desulfurized flue gas (the desulfurized flue gas temperature is 130 ℃, the composition is HCL 12mg/m 3,HF 12mg/m3, the volume concentration of CO is 1.5%, and the content of VOCs is 100mg/m 3,NOx is 417mg/m 3,SO220mg/Nm3);
Introducing the desulfurization flue gas into a dechlorination defluorination tower 2 through a desulfurization flue gas inlet 1 (the dosage of a dechlorination defluorination adsorbent is 10m 3, the space velocity is 5000h -1), removing hydrogen halide (the removal efficiency is 80%), and further reducing the concentration of SO 2 to 2mg/Nm 3; the obtained dehydrohalogenation flue gas (130 ℃) flows through a flame arrester 3, then enters a heat exchanger 6 for heat exchange and heating, so that the flue gas is heated to the catalytic oxidation temperature (180 ℃), and is sent to a catalytic tower 7, catalytic oxidation is carried out under the condition of a space velocity of 5000h -1 (catalyst consumption of 10m 3), the obtained flue gas is heated to 291 ℃ (CO conversion rate of 98%, heat exchange efficiency of 80%), the heated flue gas is mixed with ammonia gas from a reducing agent inlet 9 through a rectifier 8 and then enters an NH 3 -SCR reactor 10 for selective catalytic reduction reaction (catalyst consumption of 8.5m 3), the obtained denitration flue gas (temperature of 261 ℃) is sent to the heat exchanger 6, heat exchange is carried out on the denitration flue gas and the dehydrohalogenation flue gas, and the denitration flue gas (119 ℃) after heat exchange is discharged after heat exchange reaches the standard through a flue gas outlet 11 after heat exchange.
Example 2
The sintering flue gas (flow rate 100000Nm 3/h,SO2 concentration 450mg/Nm 3; CO volume concentration 1.8%, VOCs content 100mg/m 3;NOx content 400mg/m 3; HCl content 17mg/m 3, HF content 8mg/m 3) is desulfurized by dry method to obtain desulfurized flue gas (desulfurized flue gas temperature 120 ℃, composition HCl 17mg/m 3, HF 8mg/m 3, CO volume concentration 1.8%, VOCs content 100mg/m 3,NOx content 400mg/m 3,SO2 25mg/Nm3);
Introducing the desulfurization flue gas into a dechlorination defluorination tower 2 through a desulfurization flue gas inlet 1 (the dosage of a dechlorination defluorination adsorbent is 20m 3, the space velocity is 5000h -1), removing hydrogen halide (the removal efficiency is 80%), and further reducing the concentration of SO 2 to 2mg/Nm 3; the obtained dehydrohalogenation flue gas (120 ℃) flows through the flame arrester 3, then enters the heat exchanger 6 for heat exchange and heating, so that the flue gas is heated to the catalytic oxidation temperature (170 ℃), the flue gas is sent to the catalytic tower 7, catalytic oxidation (catalyst dosage 17m 3) is carried out under the condition of a space velocity of 5000h -1, CO and VOCs are removed, the heat generated in the catalytic oxidation process heats the obtained flue gas to 280 ℃ (the CO conversion rate is 95%, the heat exchange efficiency is 80%), the heated flue gas is mixed with the reducing agent urea from the reducing agent inlet 9 through the rectifier 8 and then enters the NH 3 -SCR reactor 10, the selective catalytic reduction reaction (catalyst dosage 17m 3) is carried out, the obtained denitration flue gas (the temperature is 270 ℃) is sent to the heat exchanger 6, the denitration flue gas subjected to heat exchange with the dehydrohalogenation flue gas, and the denitration flue gas (124 ℃) after heat exchange reaches the standard and is discharged after heat exchange through the flue gas outlet 11.
Example 3
Dry desulfurizing the coke oven fume (flow: 100000Nm 3/h,SO2 concentration 400mg/Nm 3; CO volume concentration 1.2%, VOCs content 50mg/m 3;NOx content 335mg/m 3; HCl content 15mg/m 3, HF content 4mg/m 3) to obtain desulfurized fume (desulfurized fume temperature 130 ℃, composition: HCl 15mg/m 3, HF 4mg/m 3, CO volume concentration 1.2%, VOCs content 50mg/m 3,NOx content 335mg/m 3,SO2 20mg/Nm3);
Introducing the desulfurization flue gas into a dechlorination defluorination tower 2 through a desulfurization flue gas inlet 1 (the dosage of a dechlorination defluorination adsorbent is 20m 3, the space velocity is 5000h -1), removing hydrogen halide (the removal efficiency is 80%), and further reducing the concentration of SO 2 to 3mg/Nm 3; the obtained dehydrohalogenation flue gas (130 ℃) flows through the flame arrester 3, then enters the heat exchanger 6 for heat exchange and heating, so that the flue gas is heated to the catalytic oxidation temperature (180 ℃), and then is sent to the catalytic tower 7, catalytic oxidation is carried out under the condition of a space velocity of 5000h -1 (catalyst consumption of 17m 3), the obtained flue gas is heated to 255 ℃ (CO conversion rate of 98%, heat exchange efficiency of 80%) by heat generated in the catalytic oxidation process, the heated flue gas is mixed with ammonia gas from the reducing agent inlet 9 through the rectifier 8 and then enters the NH 3 -SCR reactor 10 for selective catalytic reduction reaction (catalyst consumption of 17m 3), so that denitration flue gas (temperature of 242 ℃) is obtained, the obtained denitration flue gas is sent to the heat exchanger 6 for heat exchange with the dehydrohalogenation flue gas, and the denitration flue gas after heat exchange (114 ℃) reaches the standard and is discharged through the flue gas outlet 11 after heat exchange.
Example 4
Wet desulfurizing the Pb-Zn fuming furnace fume (flow: 100000Nm 3/h,SO2 concentration 500mg/Nm 3; CO volume concentration 3%, VOCs content 100mg/m 3;NOx content 375mg/m 3; HCl content 15mg/m 3, HF content 12mg/m 3) to obtain desulfurized fume (desulfurized fume temperature: 65 ℃, water vapor content 15%, HCl 15mg/m 3, HF 12mg/m 3, CO volume concentration 3%, VOCs content 100mg/m 3, NOx content 375mg/m 3,SO2 content 20mg/m 3);
Introducing the desulfurization flue gas into a dechlorination defluorination tower 2 through a desulfurization flue gas inlet 1 (the dosage of a dechlorination defluorination adsorbent is 20m 3, the space velocity is 5000h -1), removing hydrogen halide (the HCl removal efficiency is 80%, the HF removal efficiency is 74%), further reducing the concentration of SO 2 to 3mg/Nm 3, enabling the obtained dehydrohalogenation flue gas (65 ℃) to flow through a flame arrester 3, then introducing the obtained flue gas into a heat exchanger 6 for heat exchange and heating, enabling the flue gas to be heated to a catalytic oxidation temperature (100 ℃), sending the flue gas to a catalytic tower 7, carrying out catalytic oxidation (the dosage of the catalyst is 15m 3) under the space velocity of 5000h -1), enabling the obtained flue gas to be heated to 280 ℃ (the CO conversion rate is 90%, the heat exchange efficiency is 80%), enabling the flue gas after the temperature-heated flue gas to be mixed with ammonia gas from a reducing agent inlet 9 through a rectifier 8, then entering into a NH 3 -SCR reactor 10, carrying out selective catalytic reduction (the catalyst dosage is 15m 3), obtaining denitration flue gas 253, sending the obtained denitration flue gas into the heat exchanger 6, carrying out heat exchange with the denitration flue gas, and carrying out heat exchange with the denitration flue gas to reach the standard (130 ℃), and discharging the flue gas after the flue gas reaches the standard (130 ℃).
Example 5
The flue gas of the rotary kiln (the flow rate is 50000Nm 3/h,SO2, the concentration is 450mg/Nm 3; the volume concentration of CO is 1.5%, the blast furnace gas is supplemented with 1% CO (1% is relative to the volume content of CO in the blast furnace gas), the content of VOCs is 100mg/m 3;NOx and 340mg/m 3, the content of HCl is 17mg/m 3 and the content of HF is 9mg/m 3) is subjected to wet desulfurization to obtain desulfurized flue gas (the temperature of the desulfurized flue gas is 60 ℃, the water vapor content is 20%, the HCI is 17mg/m 3, the volume concentration of HF is 9mg/m 3, the volume concentration of CO is 1.5% and the blast furnace gas is supplemented, so that the concentration of CO is 2.5%, the content of VOCs is 100mg/m 3 and the content of NOx is 340mg/m 3,SO225mg/Nm3);
Introducing the desulfurization flue gas into a dechlorination defluorination tower 2 through a desulfurization flue gas inlet 1 (the dosage of a dechlorination defluorination adsorbent is 10m 3, the space velocity is 5000h -1), removing hydrogen halide (the HCl removal efficiency is 80%, the HF removal efficiency is 82%), further reducing the concentration of SO 2 to 2mg/Nm 3, mixing the blast furnace gas from a blast furnace gas inlet 4 with the dehydrohalogenation flue gas (60 ℃) through a variable frequency fan (5), then introducing the mixed gas into a heat arrester 3, introducing the mixed gas into a heat exchanger 6 for heat exchange and heating to the temperature of catalytic oxidation (95 ℃), introducing the mixed gas into a catalytic tower 7, carrying out catalytic oxidation (the dosage of a catalyst is 9m 3) under the space velocity of 5000h -1), heating the obtained flue gas to 242 ℃ (the CO conversion rate is 85%, the heat exchange efficiency is 80%), mixing the heated flue gas with ammonia gas from a reducing agent inlet 9 through a rectifier 8, introducing the mixed gas into a NH 3 -SCR reactor 10, carrying out selective catalytic reduction reaction (the catalyst is 9m 3), obtaining denitration flue gas (the temperature is 230 ℃), introducing the obtained flue gas into a heat exchanger for heat exchange and discharging the obtained flue gas after the denitration flue gas reaches the standard (the denitration flue gas reaches the temperature of the denitration flue gas 11).
Example 6
Wet desulfurizing the coke oven fume (flow rate of 80000Nm 3/h,SO2, concentration of 400mg/Nm 3; volume concentration of CO of 2.6%, content of VOCs of 100mg/m 3;NOx of 200mg/m 3; content of HCL of 12mg/m 3, content of HF of 10mg/m 3) to obtain desulfurized fume (desulfurized fume temperature of 63 ℃ C., moisture content of 18%, HCL of 12mg/m 3, HF of 10mg/m 3, CO concentration of 2.6%, VOCs of 50mg/m 3, NOx content of 200mg/m 3,SO220mg/Nm3);
Introducing the desulfurization flue gas into a dechlorination defluorination tower 2 through a desulfurization flue gas inlet 1 (the dosage of a dechlorination defluorination adsorbent is 17m 3, the airspeed is 4700h -1), removing hydrogen halide (the removal efficiency is 80%), and further reducing the concentration of SO 2 to 3mg/Nm 3; the obtained dehydrohalogenation flue gas (63 ℃) flows through the flame arrester 3, then enters the heat exchanger 6 for heat exchange and heating, so that the flue gas is heated to the catalytic oxidation temperature (96 ℃), and is sent to the catalytic tower 7, under the condition of the airspeed of 4700h -1, (the catalyst dosage of 10m 3), the obtained flue gas is heated to 244 ℃ (the CO conversion rate of 85 percent, the heat exchange efficiency of 80%) by the heat generated in the catalytic oxidation process, the heated flue gas is mixed with ammonia gas from the reducing agent inlet 9 through the rectifier 8, then enters the NH 3 -SCR reactor 10 for selective catalytic reduction reaction (the catalyst dosage of 10m 3), so that denitration flue gas (the temperature of 231 ℃) is obtained, the obtained denitration flue gas is sent to the heat exchanger 6 for heat exchange with the dehydrohalogenation flue gas, and the denitration flue gas after heat exchange (117 ℃) reaches the standard and is discharged through the flue gas outlet 11 after heat exchange.
The denitration efficiency of the selective catalytic reduction in examples 1 to 6 is shown in table 1, and the exhaust gas concentrations at the outlets in examples 1 to 6 are calculated by analysis using a flue gas analyzer, and the results are shown in table 1:
table 1 denitration efficiency and inlet and outlet exhaust gas concentrations of examples 1 to 6
As is clear from Table 1, the method of the present invention has high denitration efficiency, and can realize the synergistic purification of CO, VOCs, NOx and hydrogen halide.
The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (4)
1. The method for cooperatively purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas is characterized by utilizing a CO, VOCs, NOx and hydrogen halide cooperative purifying device in the metallurgical flue gas, wherein the CO, VOCs, NOx and hydrogen halide cooperative purifying device in the metallurgical flue gas comprises a dechlorination defluorination tower (2), a heat exchanger (6), a catalytic tower (7), a rectifier (8) and an NH 3 -SCR reactor (10) which are sequentially connected, and the outlet end of the NH 3 -SCR reactor (10) is connected with the heat exchanger (6);
The device also comprises a reducing agent inlet (9), a flame arrester (3) and a variable frequency fan (5), wherein the reducing agent inlet (9) is arranged on the NH 3 -SCR reactor (10); the flame arrester (3) is connected with the dechlorination defluorination tower (2); the variable frequency fan (5) is connected with the flame arrester (3);
The method for purifying CO, VOCs, NOx and hydrogen halide in metallurgical flue gas in a synergistic way comprises the following steps:
Supplementing blast furnace gas containing 1% of CO into the flue gas tail gas of the rotary kiln, wherein 1% is relative to the volume content of CO in the blast furnace gas, and desulfurizing by adopting a wet method to obtain desulfurized flue gas;
Introducing the desulfurization flue gas into a dechlorination defluorination tower (2) through a desulfurization flue gas inlet (1), wherein the dosage of a dechlorination defluorination adsorbent is 10m 3, the space velocity is 5000 and h -1, hydrogen halide is removed, the concentration of SO 2 is further reduced to 2 mg/Nm 3, the blast furnace gas from a blast furnace gas inlet is mixed with 60 ℃ dehydrohalogenation flue gas through a variable frequency fan (5) and then flows through a flame arrester (3), the mixed gas enters a heat exchanger (6) for heat exchange and temperature rise, the flue gas is heated to the temperature of catalytic oxidation of 95 ℃, the flue gas is sent to a catalytic tower (7), catalytic oxidation is carried out under the condition of space velocity of 5000 h -1, the heat generated in the catalytic oxidation process is used for heating the flue gas to 242 ℃, the heated flue gas is mixed with ammonia gas from a reducing agent inlet (9) through a rectifier (8) and then enters an NH 3 -SCR reactor (10), the selective catalytic reduction reaction is carried out, the flue gas temperature of the obtained denitration flue gas is 230 ℃, the obtained denitration flue gas is sent to a heat exchanger (6), the flue gas after the denitration flue gas reaches the temperature of 115 ℃ after the denitration flue gas reaches the standard, and the temperature of the denitration flue gas is subjected to heat exchange and the denitration flue gas is discharged after the flue gas is subjected to the heat exchange;
The metallurgical flue gas comprises SO 2, CO, VOCs, NOx and hydrogen halide, and the concentration of SO 2 is 400-500 mg/Nm 3; the volume concentration of the CO is 0.6-3%; the content of the VOCs is 50-200 mg/m 3; the content of the NOx is 200-600 mg/m 3;
the hydrogen halide comprises HCl and HF, wherein the content of the HCl is 12-17 mg/m 3, and the content of the HF is 4-12 mg/m 3.
2. The synergistic process for the purification of CO, VOCs, NOx and hydrogen halide in metallurgical off-gas as claimed in claim 1, wherein the metallurgical off-gas comprises one or more of sinter off-gas, coke oven off-gas, lead zinc fuming furnace off-gas and rotary kiln off-gas.
3. The synergistic process for the purification of CO, VOCs, NOx and hydrogen halide in metallurgical off-gas as claimed in claim 1, wherein the catalyst for catalytic oxidation is Pt/Al 2O3.
4. The synergistic process for the purification of CO, VOCs, NOx and hydrogen halide in metallurgical off-gas as claimed in claim 1, wherein the catalyst for the selective catalytic reduction is V 2O5-WO3/TiO2.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003002912A1 (en) * | 2001-06-29 | 2003-01-09 | Seghers Keppel Technology Group Nv | Flue gas purification device for an incinerator |
| CN105233672A (en) * | 2015-11-05 | 2016-01-13 | 云南蓝澈科技有限公司 | Denitration and decarburization device for sintering flue gas and process thereof |
| CN109482052A (en) * | 2018-12-06 | 2019-03-19 | 中国科学院过程工程研究所 | CO and NO in a kind of purifying sintering flue gasxDevice and method |
| CN109482049A (en) * | 2019-01-02 | 2019-03-19 | 武汉科林精细化工有限公司 | A kind of coke oven flue gas dry desulfurization denitration purification integral process |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003002912A1 (en) * | 2001-06-29 | 2003-01-09 | Seghers Keppel Technology Group Nv | Flue gas purification device for an incinerator |
| CN105233672A (en) * | 2015-11-05 | 2016-01-13 | 云南蓝澈科技有限公司 | Denitration and decarburization device for sintering flue gas and process thereof |
| CN109482052A (en) * | 2018-12-06 | 2019-03-19 | 中国科学院过程工程研究所 | CO and NO in a kind of purifying sintering flue gasxDevice and method |
| CN109482049A (en) * | 2019-01-02 | 2019-03-19 | 武汉科林精细化工有限公司 | A kind of coke oven flue gas dry desulfurization denitration purification integral process |
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