CN100377763C - Method for purifying flue gas by application of active coke - Google Patents
Method for purifying flue gas by application of active coke Download PDFInfo
- Publication number
- CN100377763C CN100377763C CNB2004100862724A CN200410086272A CN100377763C CN 100377763 C CN100377763 C CN 100377763C CN B2004100862724 A CNB2004100862724 A CN B2004100862724A CN 200410086272 A CN200410086272 A CN 200410086272A CN 100377763 C CN100377763 C CN 100377763C
- Authority
- CN
- China
- Prior art keywords
- flue gas
- activated coke
- purifying
- coke
- purifies
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000571 coke Substances 0.000 title claims abstract description 87
- 239000003546 flue gas Substances 0.000 title claims abstract description 70
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 65
- 238000000034 method Methods 0.000 title claims abstract description 42
- 238000006243 chemical reaction Methods 0.000 claims abstract description 10
- 239000007921 spray Substances 0.000 claims abstract description 7
- 238000006477 desulfuration reaction Methods 0.000 claims description 19
- 230000023556 desulfurization Effects 0.000 claims description 19
- 238000002347 injection Methods 0.000 claims description 19
- 239000007924 injection Substances 0.000 claims description 19
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 9
- 238000002156 mixing Methods 0.000 claims description 7
- 239000003595 mist Substances 0.000 claims description 3
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 abstract description 7
- 229910052753 mercury Inorganic materials 0.000 abstract description 7
- 229910001385 heavy metal Inorganic materials 0.000 abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 2
- 239000003344 environmental pollutant Substances 0.000 abstract 1
- 231100000719 pollutant Toxicity 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 15
- 238000004140 cleaning Methods 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 239000003638 chemical reducing agent Substances 0.000 description 4
- 239000003245 coal Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 230000008929 regeneration Effects 0.000 description 4
- 238000011069 regeneration method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000000746 purification Methods 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000000356 contaminant Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000005864 Sulphur Substances 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 229910052956 cinnabar Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
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- Treating Waste Gases (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
Abstract
The present invention discloses a method for purifying flue gas by using active coke, which relates to a flue gas purifying method. The method for purifying flue gas by using active coke provided by the present invention comprises the following steps that: the flue gas is purified in a desulphurization and denitration reaction device which comprises active coke and is composed of two segments of moving bed reactors, wherein the flue gas is also purified by a pipeline which sprays active coke. The method for purifying flue gas by using active coke of the present invention can simultaneously remove heavy metal pollutants, such as SO2, NO<X>, mercury, etc., has the advantages of high flue gas purifying rate, low engineering investment, no water consumption during a purifying course, etc., and has wide popularization and application prospects.
Description
Technical field
The present invention relates to flue gas purifying method, particularly relate to a kind of method of purifying flue gas by application of active coke.
Background technology
Develop clean coal technology be the strategy of sustainable development it.China's atmosphere pollution is mainly caused by fire coal, the NO that is produced
xWith SO
2Can cause acid rain harm; And the environmental pollution that heavy metals such as mercury, lead, chromium may cause after burning in the coal has got more and more people's extensive concerning, and is example with mercury, and mercury common form with cinnabar and free mercury in coal exists, and evaporate in the flue gas harmful to people and animals during its burning more.
At present, external gas cleaning is most of adopts Wet technique, but the wet type flue gas desulphurization technology at home some areas power plant apply and be restricted.The activated coke flue gases purification is a kind of advanced person's a dry method flue gases purification, developmental research methods such as activated coke fixed bed, moving bed.The inventor has applied for that on June 25th, 2004 name is called the patent of invention of " a kind of flue gas desulfurization, method of denitration ", and application number is 200410038037.X.This flue gas desulfurization, method of denitration carry out in the desulfurization and denitrification reaction device that is made of two sections moving-burden bed reactors, and flow process comprises: second section reactor from the activated coke of first section reactor is housed, the SO in the adsorbing and removing flue gas bottom flue gas is introduced into
2, then with NH
3Or H
2After the mixing of CO mist, enter the first section reactor that is added with activated coke in top, react the nitrogen oxide that removes wherein with the activated coke in the first section reactor in top, generate gas and enter atmosphere.This method is at NH
3Or H
2Under the effect of CO mixing reducing agent, have higher denitration performance, solved problems such as existing reaction speed is slow in flue gas desulfurization, the denitration, denitration efficiency is low, be mainly used in flue gas desulfurization and denitration; But the used moving bed device of this technology is general huger, the equipment investment height, and in addition, generally by burning disposal, utilization rate is not high, makes operating cost higher for the broken activated coke that is produced in desulfurization, denitrification process.
Summary of the invention
The flue gas purifying method that the purpose of this invention is to provide a kind of application of active coke high-efficiency and continuous.
The method of purifying flue gas by application of active coke provided by the present invention, comprise that flue gas purifies in the desulfurization and denitrification reaction device that is made of two sections moving-burden bed reactors of activated coke is housed, its flow process is: second section reactor from the activated coke of first section reactor is housed, the SO in the adsorbing and removing flue gas bottom flue gas is introduced into
2, then with NH
3Or H
2After the mixing of CO mist, enter the first section reactor that is added with activated coke in top, react the nitrogen oxide that removes wherein with the activated coke in the first section reactor in top, it is characterized in that: described flue gas also purifies by the pipeline that sprays activated coke.
Flue gas purifying method of the present invention has multiple compound mode, and flue gas can purify by the desulfurization and denitrification reaction device that is made of two sections moving-burden bed reactors that activated coke is housed earlier, and then purifies by the pipeline that sprays activated coke.Also can purify by the pipeline that sprays activated coke earlier, and then purify by the desulfurization and denitrification reaction device that constitutes by two sections moving-burden bed reactors that activated coke is housed.
In order to improve gas cleaning efficient, described duct injection derives from the activated coke that described two sections moving-burden bed reactors produce with activated coke, and use the back of it need being clayed into power usually.
Flue gas separates flue gas through deduster after purifying through the duct injection activated coke with powder activity Jiao, can emptying or be used to carry out next step desulfurization, denitration.
In the present invention, described moving bed air speed is 800-2000h
-1, the emitted dose of duct injection activated coke is 10-400mg activated coke/m
3Flue gas.In order to guarantee the effect of gas cleaning, the temperature of flue gas at 100-180 ℃ for well.
The preferred request for utilization of activated coke of the present invention number is 02146004.3, the activated coke of denomination of invention for preparing in the patent application of " a kind of preparation process of active carbon ".The patent No. that two sections moving-burden bed reactors that desulfurization, denitration reaction carry out can select for use the present inventor to invent is 00254473.3, and name is called disclosed reactor in " a kind of flue gas desulfur device ".
The method of purifying flue gas by application of active coke of the present invention is divided into two sections, wherein adopts the desulfurization of activated coke moving-burden bed reactor, denitrating technique schematic diagram shown in Figure 1A, adopts the duct injection activated coke to purify the process schematic representation of flue gas shown in Figure 1B.The broken activated coke that produces in moving bed is through SO repeatedly
2Absorption and thermal regeneration are handled, because thermal regeneration is the sulfuric acid on activated coke surface and the carbon generation oxidation reaction on activated coke surface, its absorption demercuration performance is significantly increased, and after it can being clayed into power, is used for duct injection and purifies flue gas.In the present invention, because purifying, duct injection removes part SO in the flue gas
2, NO
XWith heavy metal contaminants such as mercury, reduced the pressure of activated coke moving bed gas cleaning, make the activated coke moving bed air speed can be from the 200-600h of common process
-1Bring up to 800-2000h
-1, can make the moving-burden bed reactor volume-diminished, and the used activated coke performance of duct injection height both can significantly improve gas cleaning efficient, can reduce the waste of moving-bed active coke again, save the activated coke consumption, the gas cleaning cost is significantly reduced.The method of purifying flue gas by application of active coke of the present invention can remove SO simultaneously
2, NO
XWith heavy metal contaminants such as mercury, have that gas cleaning rate height, construction investment are low, a purification process advantage such as consume water not, have popularizing application prospect widely.
Description of drawings
Figure 1A is for adopting the desulfurization of activated coke moving-burden bed reactor, denitrating technique schematic diagram;
Figure 1B purifies the process schematic representation of flue gas for adopting the duct injection activated coke;
Fig. 2 is the structural representation of duct injection clarifier.
The specific embodiment
Embodiment 1, gas cleaning desulfurization, denitration, demercuration
1, flue gas adopts the activated coke moving-burden bed reactor to purify
Utilize two sections moving-burden bed reactors of Nanjing Electric Power Automation Equipment head factory production to remove sulphur and nitre in the flue gas.SO in the flue gas
2Concentration is 5000mg/m
3, NO
XConcentration is 500mg/m
3, Hg content is 20ug/m
3, temperature is 120 ℃, the moving-burden bed reactor air speed is 1000h
-1Take off SO
x/ take off NO
XFirst section of reactor is added with 150 kilograms of activated coke; The NH that adds
3With CO mixing reductant concentration be 500 mg/m
3(NH
3/ CO mol ratio is 20), temperature is 10-100 ℃, charge flow rate is 500m
3/ h.Regenerator is sent in activated coke recovery through second section desulphurization reaction, and 200-600u ℃ of heating 3-30h regeneration down, the CO gas that regenerative process produces is sent into and taken off SO
x/ take off NO
XReactor, the activated coke that regeneration is good are added to send into after the new activated coke of 0.5-10% of its total amount and are taken off SO
x/ take off NO
XFirst section of reactor, the next circulation of beginning.
2, flue gas adopts the duct injection activated coke to purify
It is 100-320 purpose powder that the broken activated coke that the last step was generated in moving bed is worn into granularity, is used for the duct injection clarifier.
The structure of this duct injection clarifier as shown in Figure 2, activated coke storage warehouse 11, doser 12, gas compressor 13 and activated coke conveyance conduit 14 are formed the activated coke induction system, have row's activated coke input hole 21 to be used for spraying into activated coke to pipeline 22 on the pipeline 22, flue gas flows in pipeline 22.The activated coke that is stored in activated coke storage warehouse 11 enters doser 12, with gas compressor 13 to wherein being pressed into air, emitted dose by doser 12 control activated coke, the ejection activated coke is sent in the pipeline 22 from activated coke input hole 21 through activated coke conveyance conduit 14, purifies the flue gas in the pipeline 22.
To be passed into through the flue gas of moving-burden bed reactor in the duct injection clarifier, with 150mg activated coke powder/m
3The emitted dose of flue gas is sprayed activated coke in pipeline.
Whole process flue gas SO
2Removal efficiency is 95%, NO
XRemoval efficiency is 79%, and the Hg removal efficiency is 85%.
Embodiment 2, gas cleaning desulfurization, denitration, demercuration
1, flue gas adopts the duct injection activated coke to purify
Flue gas SO
2Content is 3000mg/m
3, NO
XConcentration is 300mg/m
3, Hg content is 10ug/m
3, flue-gas temperature is 120 ℃, and this flue gas is passed in the duct injection clarifier as embodiment 1, with 380mg activated coke powder/m
3The emitted dose of flue gas is sprayed activated coke in pipeline.Wherein, initial used activated coke powder can adopt new activated coke, and later process can adopt the broken activated coke that generates in moving bed.
2, flue gas adopts the activated coke moving-burden bed reactor to purify
Gained flue gas of last step is passed in the moving-burden bed reactor as embodiment 1, and wherein, the moving bed air speed is 800h
-1, the NH of adding
3With the concentration of CO mixing reducing agent be 300PPm (NH
3/ CO mol ratio is 5), all the other processes are carried out according to embodiment 1.
Whole process flue gas SO
2Removal efficiency is 98%, NO
XRemoval efficiency is 83%, and the Hg removal efficiency is 90%.
Embodiment 3, gas cleaning desulfurization, denitration, demercuration
Flue gas SO
2Content is 7500 mg/m
3, NO
XConcentration is 600 mg/m
3, Hg content is 25ug/m
3, flue-gas temperature is 180 ℃, carries out gas cleaning continuously according to step 1 and the step 2 of embodiment 1, wherein, the moving bed air speed is 900h
-1, the H of adding
2With the concentration of CO mixing reducing agent be 600mg/m
3(H
2/ CO mol ratio is 0.5), activated coke duct injection amount is 50mg/m
3Whole process SO
2Removal efficiency is 90%, NO
XRemoval efficiency is 75%, and the Hg removal efficiency is 80%.
Claims (9)
1. the method for a purifying flue gas by application of active coke, comprise that flue gas purifies in the desulfurization and denitrification reaction device that is made of two sections moving-burden bed reactors of activated coke is housed, its flow process is: second section reactor from the activated coke of first section reactor is housed, the SO in the adsorbing and removing flue gas bottom flue gas is introduced into
2, then with NH
3Or H
2After the mixing of CO mist, enter the first section reactor that is added with activated coke in top, react the nitrogen oxide that removes wherein with the activated coke in the first section reactor in top, it is characterized in that: described flue gas also purifies by the pipeline that sprays activated coke.
2. method according to claim 1 is characterized in that: described flue gas purifies by the desulfurization and denitrification reaction device that is made of two sections moving-burden bed reactors that activated coke is housed earlier, and then purifies by the pipeline that sprays activated coke.
3. method according to claim 1 is characterized in that: described flue gas purifies by the pipeline that sprays activated coke earlier, and then purifies by the desulfurization and denitrification reaction device that is made of two sections moving-burden bed reactors that activated coke is housed.
4. according to claim 1 or 2 or 3 described methods, it is characterized in that: described duct injection derives from the activated coke that described two sections moving-burden bed reactors produce with activated coke.
5. according to claim 1 or 2 or 3 described methods, it is characterized in that: described two sections moving-burden bed reactor air speeds are 800-2000h
-1
6. according to claim 1 or 2 or 3 described methods, it is characterized in that: the emitted dose of described duct injection activated coke is 10-400mg activated coke/m
3Flue gas.
7. method according to claim 5 is characterized in that: the emitted dose of described duct injection activated coke is 10-400mg activated coke/m
3Flue gas.
8. according to claim 1 or 2 or 3 described methods, it is characterized in that: the temperature of described flue gas is 100-180 ℃.
9. method according to claim 7 is characterized in that: the temperature of described flue gas is 100-180 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100862724A CN100377763C (en) | 2004-10-29 | 2004-10-29 | Method for purifying flue gas by application of active coke |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100862724A CN100377763C (en) | 2004-10-29 | 2004-10-29 | Method for purifying flue gas by application of active coke |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1765471A CN1765471A (en) | 2006-05-03 |
| CN100377763C true CN100377763C (en) | 2008-04-02 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100862724A Expired - Lifetime CN100377763C (en) | 2004-10-29 | 2004-10-29 | Method for purifying flue gas by application of active coke |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101310827B (en) * | 2008-02-22 | 2011-12-28 | 北京国电清新环保技术股份有限公司 | Activated charcoal gas cleaning method and device thereof |
| CN106474916B (en) * | 2015-09-01 | 2019-07-23 | 中国科学院过程工程研究所 | A kind of activated coke combined desulfurization and denitration device and method for flue gas |
| CN106621701B (en) * | 2016-12-20 | 2020-09-11 | 神华集团有限责任公司 | Flue gas desulfurization system |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1435273A (en) * | 2002-01-29 | 2003-08-13 | 国家电站燃烧工程技术研究中心 | Cyclic fluidized bed active coke desulfurating and sulfur reutilization method |
| US6616905B1 (en) * | 1998-04-07 | 2003-09-09 | Chiyoda Corporation | Desulfurization of exhaust gases using activated carbon catalyst |
-
2004
- 2004-10-29 CN CNB2004100862724A patent/CN100377763C/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6616905B1 (en) * | 1998-04-07 | 2003-09-09 | Chiyoda Corporation | Desulfurization of exhaust gases using activated carbon catalyst |
| CN1435273A (en) * | 2002-01-29 | 2003-08-13 | 国家电站燃烧工程技术研究中心 | Cyclic fluidized bed active coke desulfurating and sulfur reutilization method |
Non-Patent Citations (1)
| Title |
|---|
| 活性焦脱硫脱氮技术开发与研究. 刘静，肖友国，张文辉，刘春兰.二氧化硫污染治理技术汇编——2001年全国烟气脱硫成套技术工程应用实例分析及学术研讨会论文集. 2001 * |
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Owner name: CHINA SHENHUA ENERGY STOCK CO., LTD. Free format text: FORMER OWNER: ZHANG WENHUI Effective date: 20100521 Free format text: FORMER OWNER: WANG LING LI SHURONG LIU CHUNLAN |
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Free format text: CORRECT: ADDRESS; FROM: 100013 COAL-CHEMICAL RESEARCH INSTITUTE, INSTITUTE OF COAL, NO.5, QINGNIANGOUDONG ROAD, HEPINGLI, CHAOYANG DISTRICT, BEIJING CITY TO: 100011 4/F, ZHOUJI BUILDING, NO.16 ANDE ROAD, DONGCHENG DISTRICT, BEIJING |
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Effective date of registration: 20100521 Address after: 100011 Beijing city Dongcheng District No. 16 Andrew intercontinental 4 storey building Patentee after: China Shenhua Energy Co.,Ltd. Address before: 100013, Beijing, Hepingli Youth ditch East Road, No. 5 coal branch of the Chaoyang District Institute of coal Co-patentee before: Wang Ling Patentee before: Zhang Wenhui Co-patentee before: Li Shurong Co-patentee before: Liu Chunlan |
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