CN101333464B - Desulphurization process by vacuum ammonia method - Google Patents

Desulphurization process by vacuum ammonia method Download PDF

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Publication number
CN101333464B
CN101333464B CN2008101453997A CN200810145399A CN101333464B CN 101333464 B CN101333464 B CN 101333464B CN 2008101453997 A CN2008101453997 A CN 2008101453997A CN 200810145399 A CN200810145399 A CN 200810145399A CN 101333464 B CN101333464 B CN 101333464B
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ammonia
hcn
gas
coal gas
coke
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CN2008101453997A
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CN101333464A (en
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马永伟
李洪钧
张继明
华祥
顾兴林
魏盼冬
刘向阳
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马永伟
魏盼冬
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Abstract

The invention provides a novel process for removing ammonia, H2S and HCN in coke-oven gas in the coking industry, comprising: taking ammonia in coke-oven gas and the residual ammonia water as an alkali source to have reaction with H2S and HCN in the coke-oven gas, then carrying out the resolution in a regeneration tower, removing ammonia in the obtained mixed gas by a saturex firstly, and producing elemental sulfur by the residual sour gas in a Claus furnace. The process is characterized in that: a rich liquid is obtained by utilizing the strong ammonia water obtained by ammonia in the coal gas to have reaction with H2S and HCN in the coal gas under the vacuum state, the tower bottom takes the sensible heat of flue waste gas as a heat source, the resolution is implemented in the regeneration tower under the negative pressure, and the obtained barren solution on the tower bottom is used for rewashing the ammonia. The process has advantages of simple technique, low running cost, investment saving, and high ammonia, H2S and HCN removal efficiency. The invention is an innovation of ammonia, H2S and HCN removing process in coal gas for coke plants.

Description

Desulphurization process by vacuum ammonia
Technical field
The invention provides a kind of complete processing that removes that is widely used in ammonia, H2S and HCN in the coking industry coal gas.
Background technology
In the coking production process, contain ammonia, H in the coal gas of generation 2Gas such as S and HCN.Ammonia is serious to equipment corrosion, H 2S can produce SO when together burning with coke-oven gas 2Atmosphere pollution, and HCN is hypertoxic gas, therefore when utilizing coke-oven gas to carry out the product deep processing, must remove these gases, and H in the coal gas 2Can the height of S content be to weigh a steel mill process the rigid index of high-quality steel, if removed the above-mentioned several kinds of gases in the coal gas, not only solved above-mentioned several problem, and can increase benefit for enterprise simultaneously.If for example the ammonia in the coal gas can be reclaimed, can produce sulfuric acid or dense ammonium water, when chemical fertilizer is used.If can remove the H in the coal gas 2S can produce the simple substance elementary sulfur.And present ammonia, the H of removing 2Several kinds of technologies of S and HCN are not complex process, are exactly that investment is too high, and running cost is too high, and removal efficiency is too low, and the product sulfur value of production is low because of purity is not high, or absorption agent is poisonous etc., does not still solve question of substance.
Summary of the invention
The new process for processing that the present invention provides a kind of coking industry to remove ammonia in the coke-oven gas, sulphur hydrogen and prussic acid, the problems such as sulphur poor quality of solved traditional technology energy consumption height, complex process, absorption agent is poisonous, removal efficiency is low, producing.
Technical scheme of the present invention is a coal gas through behind the electrical tar precipitator, and with remained ammonia and the ammonia of regenerator column bottom lean solution in supercooler cooling back entering Ammonic washing tower absorption coal gas, the strong aqua 2/3rds of gained is used for absorbing the H of coal gas bottom the Ammonic washing tower 2S and HCN get into ammonia still after the wastewater heat exchange device heat exchange at the bottom of 1/3rd processes and the ammonia still, under negative pressure state, make the ammonia volatilization in the strong aqua, get into desulfuration absorbing tower again after ammonia cools off through condensed device, vacuum pump, ammonia cooler and absorb H 2S and HCN, a circulation spray pump has been installed at the desulfuration absorbing tower middle part, after the rich solution process and the rich or poor liquid heat exchange at the bottom of the regenerator column that the desulfuration absorbing tower bottom obtains, gets into regenerator column, under negative pressure state, makes ammonia, H in the rich solution 2S and HCN resolve, and after the gas mixture process condensed device refrigerated separation, to saturex, remove the ammonia in the gas mixture by the vacuum pump positive delivery, and the acid gas that saturex comes out after the supercooler cooling, gets into the acid gas separator again, gets into next procedure.The waste water of ammonia still bottom and with the cyclic ammonia water heat exchange after with the lean solution of regenerator column bottom and stack gas heat exchange after return tower at the bottom of, be that two towers provide sensible heat.Its principal character is:
After A, this technology are placed on electrical tar precipitator;
B, thionizer have added a circulation and have sprayed washing pump;
C, used alkali source are from the ammonia in coal gas and the remained ammonia;
D, ammonia still and regenerator column are in negative pressure state;
E, ammonia still bottom sensible heat provide with cyclic ammonia water, and regenerator column bottom sensible heat provides with coke oven flue waste gas;
F, ammonia still, regenerator column inside are filling-material structure;
G, ammonia, H 2S and HCN mixed gas are removed the ammonia in the mixed gas through saturex.
Vacuum ammonia process removes H in a kind of coking industry coke-oven gas 2The complete processing of S and HCN, its principal character is: part is washed the strong aqua that comes by Ammonic washing tower go thionizer to absorb the H in the coal gas 2S and HCN, all the other strong aquas are under vacuum negative pressure condition, and the ammonia vapour that obtains resolving acquisition at ammonia still is sent to the H that thionizer is used for further absorbing coal gas 2S and HCN, the rich solution that obtains in the thionizer bottom are sent to regenerator column; Under vacuum negative pressure condition, obtain resolving; The mixed steam of gained is removed ammonia vapour wherein through saturex earlier; Remaining sour gas is sent to next procedure, utilizes vacuum pump that ammonia still and regenerator column are reduced pressure, and pressure reduces to-and 81.1Kpa is to-83.1Kpa, and regenerator column is worked under vacuum, low temperature environment; The evaporation thermal source is provided by the sensible heat of cyclic ammonia water at the bottom of the ammonia still; Evaporation thermal source at the bottom of the regenerator column is provided by the sensible heat of coke oven flue waste gas; Add a circulation spray pump at the middle part of thionizer, be used for improving the H of coal gas 2The removal efficiency of S and HCN.
Vacuum ammonia process of the present invention removes H 2The S complete processing after said this technology is placed on electrical tar precipitator, is meant coke-oven gas through primary cooler and electrical tar precipitator, make gas temperature cool down by 80 ℃ drop to 23 ℃ remove with tar impurity after, guaranteed that coal gas removes H in thionizer 2The efficient of S and HCN and the obstruction that has reduced later process are simultaneously than cooling tower of HPF method minimizing traditionally; Said thionizer has added a circulation spray pump, is meant at thionizer middle part, and in order to add systemic circulation sprinkling amount, therefore most H 2S and HCN are absorbed at the thionizer middle part; Said all alkali source refers to the lean solution of coming out the free regenerator column of absorption agent bottom through behind the poor rich liquid heat exchanger from the ammonia in coal gas and the remained ammonia; Again through after the cooling of lean solution water cooler; Contact with coal gas with remained ammonia adverse current in Ammonic washing tower of coming, the ammonia that absorbs in the coal gas is H in the coal gas 2S and HCN reaction provide alkali source, and following reaction takes place in thionizer:
NH 4OH+H 2S=NH 4HS+H 2O
NH 4OH+NH 4HS=NH 42S+H 2O
NH 4OH+HCN=NH 4CN+H 2O
Thereby overcome vacuum Na 2CO 3And K 2CO 3Arts demand replenishes this problem of alkali source; Move under the subatmospheric negative pressure state of said ammonia still process and regenerator column, tower top pressure is-83.1P a, tower bottom pressure is-81.1P a, at this moment liquid seethes with excitement at 60C at the bottom of the tower, and reaction as follows takes place:
NH 42S+H 2O=NH 4OH+NH 4HS
NH 4HS+H 2O=NH 4OH+H 2S↑
NH 4CN+H 2O=NH 4OH+HCN↑
NH 4ON=NH 3↑+H 2O;
Said utilize the cyclic ammonia water sensible heat for ammonia still with utilize coke oven flue waste gas sensible heat the evaporation thermal source to be provided for regenerator column; After being meant that ammonia still and regenerator column are through the vacuum pump decompression; The boiling point of liquid of tower bottom has reduced; Therefore cyclic ammonia water that can be through being sent to coke oven and provide from the come out sensible heat of stack gases of main flue, the liquid of two tower bottoms boosts through the pump that boils again, the ammonia still bottom liquid after taking the intensification of device and cyclic ammonia water heat exchange heat again and the regenerator column bottom liquid after chimney heat exchanger and stack gases heat exchange intensification; Return into two tower bottoms, thereby cancelled the steam resource consumption; Said ammonia still and regenerator column inside are filling-material structure, are meant that this technology strong aqua all is low-temp low-pressure under operation with absorbing rich solution at regenerator column at ammonia still, have changed traditional metal tray structure, and available general filler replaces; Said ammonia, H 2O and HCN mixed gas process saturex are removed the ammonia of mixed gas, are meant the ammonia, the H that process 2Reaction as follows takes place through saturex in S and HCN:
NH 4OH+H 2SO 4=NH 4HSO 4+H 2O
NH 4HSO 4+ NH 4OH=NH 42SO 4+ H 2O removes the ammonia in the mixed gas.
The present invention is to the traditional deamination of coking industry, H 2S and HCN technology are bold in innovation, and have proposed new technical scheme, have cancelled steam, and the consumption of alkali source and other absorption agent makes the investment that exists in original technology situation high, that running cost is high, removal efficiency is low obtain radical change.
Fig. 1, the 2nd, vacuum ammonia process removes H 2The Figure of description of S
Embodiment
Among Fig. 2: 1, desulfuration absorbing tower, 2, Ammonic washing tower, 3, ammonia still, 4, regenerator column, 5, saturex, 6, sour vapour separator; 7, circulation spray pump, 8, the rich solution pump, 9, the strong aqua pump, 10, the remained ammonia water cooler, 11, lean pump, 12, the pump that boils again; 13, reboiler, 14, the pump that boils again, 15, chimney, 16, ammonia vapour water cooler, 17, vacuum pump; 18, ammoniacal liquor flow quantity self-adjusting valve, 19, water sealed tank, 20, ammonia vapour condensed device, 21, the mixed steam condensed device, 22, water sealed tank; 23, vacuum pump, 24, sour vapour water cooler, 25, the distilled ammonia wastewater pump, 26, the ammoniacal liquor interchanger, 27, poor rich liquid heat exchanger.28, lean solution water cooler, 29, the stack gas interchanger, 30 vacuum fans, 31, mother liquor tank, 32, little mother liquor pump
Patent of the present invention is implemented through following concrete steps: per hour to handle coal gas is 70,000 m 3Be example: the temperature of regenerator column 4 bottoms is that 60 ℃, flow are 60m 3/ h contains ammonia and pressurizes through lean pump 11 in the lean solution of 0.03g/L; After poor rich liquid heat exchanger 27 heat exchange to 46 ℃-48 ℃; Deliver to after the 28 water at low temperature heat exchange of lean solution water cooler 23 ℃-25 ℃ and get into Ammonic washing tower 2 epimeres, with on the dilute NaOH solution brought in and the stage casing temperature of coming be that 45 ℃-50 ℃ and flow are 30m 3, reduce to after 23 ℃-25 ℃ remained ammonia converges through remained ammonia water cooler 10 water at low temperature, in Ammonic washing tower 2 with coal gas counter current contact from desulfuration absorbing tower 1, absorb the ammonia in the coal gas, the Ammonic washing tower bottom rate is at 90m 3/ h temperature is at 28 ℃-30 ℃; Contain the strong aqua of ammonia at 8g-10g/l; Get to desulfuration absorbing tower 1 through 2/3 of strong aqua pump 9 flows, be warming up to 38 ℃-40 ℃ behind the 1/3 process ammoniacal liquor interchanger 26 of flow, get into ammonia stills 3 through flow quantity self-adjusting valve 18; 60 ℃ of distilled ammonia wastewaters of ammonia still bottom are sent to biochemical 3 after delivering to ammoniacal liquor interchanger 26 heat exchange to 45 ℃-48 ℃ after by 25 pressurizations of distilled ammonia wastewater pump; The ammonia vapour that comes out in the ammonia still top is pressurized to 25kPa-30kPa through ammonia vapour condensed device 20 recirculated water heat exchange to 35 ℃-40 ℃ by vacuum pump 17, and flow is 300m 3/ h-350m 3/ h ammonia is delivered to ammonia cooler 16 water at low temperature and is reduced to 23 ℃-25 ℃, and the flushing liquor that gets into 1 stage casing, thionizer absorption tower and circulation spray pump 7 converges sprinkling, and from the coal gas counter current contact behind the electrical tar precipitator, absorbs the H in the coal gas 2S and HCN; After the rich solution of desulfuration absorbing tower 1 bottom pressurizes through rich solution pump 8; Be delivered to poor rich liquid heat exchanger 27 temperature and be raised to 38 ℃-40 ℃ by 25 ℃, get into regenerator column 4, the mixing gas that comes out in regenerator column 4 tops is through mixed steam condensed device 21 circulating water coolings to 35 ℃-40 ℃; Be pressurized to 20kPa-30kPa by vacuum pump 23, flow is 1200m 3/ h-1400m 3/ h mixing gas is delivered to saturex 5, contacts the ammonia vapour of removing in the mixing with the dilute sulphuric acid of saturex 5, and the temperature of coming out from saturex is 50 ℃-55 ℃, and flow is 360m 3/ h-400m 3The sour vapour of/h with sour vapour water cooler 24 water at low temperature heat exchange to 25 ℃-28 ℃ of sour vapour separators 6 of entering, divides vapour to leave the acid gas entering next procedure that device 6 comes out from acid.
Make ammonia still, regeneration overhead maintenance-83.1KPa pressure through vacuum pump 17,23; Maintenance-81.1KPa pressure at the bottom of the tower; Liquid is about 60 ℃ of boilings at the bottom of the tower, and the liquid that the gas of generation and cat head get off contacts in that filling surface is reverse, and the gas in the liquid is parsed; The thermal source of ammonia still 3 bottoms is provided by the about 75 ℃ cyclic ammonia water that is sent to coke oven, and ammonia still 3 bottom liquids are by pump 12 pressurizations of boiling again, according to 700m at the bottom of the tower 3/ h internal circulating load is returned the ammonia still bottom after being warming up to 70 ℃-72 ℃, and the thermal source of regenerator column 4 bottoms is that 360 ℃ of stack gases sensible heats provide by the temperature of coming out from the coke oven main flue, and regenerator column 4 bottom liquids are by pump 14 pressurizations of boiling again, according to 2800m at the bottom of the tower 3After/h internal circulating load process stack gas interchanger 29 and the stack gases heat exchange, temperature is returned regenerator column 4 bottoms after rising to 70 ℃-72 ℃; After the flue waste vapour passed through stack gas interchanger 29 by 360 ℃, temperature was reduced to 80 ℃, is sent to chimney 15 by vacuum fan 30.
The condensing water that ammonia vapour condensed device 20 is condensed gets into water sealed tank 19; The condensing water that mixed steam condensed device 21 is condensed gets into water sealed tank 22; The fluid-tight of water sealed tank set inside, the liquid of water sealed tank 19,22 can be squeezed into system through the lean pump import and circulated; The liquid that acid vapour separator 6 separates flows into mother liquor tank 31, regularly squeezes in the saturex 5 with little mother liquor pump 32 and utilizes.

Claims (3)

1. vacuum ammonia process removes H in the coking industry coke-oven gas 2The complete processing of S and HCN, its principal character is: part is washed the strong aqua that comes by Ammonic washing tower go thionizer to absorb the H in the coal gas 2S and HCN, all the other strong aquas are under vacuum negative pressure condition, and the ammonia vapour that obtains resolving acquisition at ammonia still is sent to the H that thionizer is used for further absorbing coal gas 2S and HCN, the rich solution that obtains in the thionizer bottom are sent to regenerator column; Under vacuum negative pressure condition, obtain resolving; The mixed steam of gained is removed ammonia vapour wherein through saturex earlier; Remaining sour gas is sent to next procedure, utilizes vacuum pump that ammonia still and regenerator column are reduced pressure, and pressure reduces to-and 81.1Kpa is to-83.1Kpa, and regenerator column is worked under vacuum, low temperature environment.
2. remove H according to the said vacuum ammonia process of claim 1 2The complete processing of S and HCN is characterized in that: the evaporation thermal source is provided by the sensible heat of cyclic ammonia water at the bottom of the ammonia still; Evaporation thermal source at the bottom of the regenerator column is provided by the sensible heat of coke oven flue waste gas.
3. remove H according to the said vacuum ammonia process of claim 1 2The complete processing of S and HCN is characterized in that: added a circulation spray pump at the middle part of thionizer, be used for improving the H of coal gas 2The removal efficiency of S and HCN.
CN2008101453997A 2008-08-04 2008-08-04 Desulphurization process by vacuum ammonia method Expired - Fee Related CN101333464B (en)

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CN102277205B (en) * 2010-06-10 2014-05-07 宁波科新化工工程技术有限公司 Method for extracting salt from coke oven gas by desulfuration and decyanation
CN102485851A (en) * 2010-12-01 2012-06-06 鞍钢集团工程技术有限公司 Method and apparatus for removing acid-containing droplet in gas from soda acid neutralization deamination
CN102895848B (en) * 2011-07-27 2015-02-18 中国石油化工股份有限公司 Renewable wet flue gas desulfurization technology
CN102895840B (en) * 2011-07-27 2015-06-03 中国石油化工股份有限公司 Regenerable wet flue gas desulfurization process
CN102381688A (en) * 2011-09-06 2012-03-21 武汉科技大学 Concentrated sulfuric acid preparation method using hydrogen sulfide in manufactured gas
CN102776013A (en) * 2012-07-20 2012-11-14 黑龙江建龙钢铁有限公司 Method and device for heat preservation of coking coke tar
CN103113930B (en) * 2013-02-28 2014-11-26 武汉钢铁(集团)公司 Method and equipment for improving desulfurization efficiency of coke oven gas by vacuum potassium carbonate method
CN103113928B (en) * 2013-02-28 2014-06-18 武汉钢铁(集团)公司 Optimization process of vacuum potassium carbonate method coke oven gas desulfurization and equipment thereof
CN104212497B (en) * 2013-05-29 2018-12-14 宝钢工程技术集团有限公司 Add alkali decompression type device and its application method for coke oven gas desulfurization
CN104629818B (en) * 2015-02-03 2017-01-04 薛斌 Vacuum carbonate desulphurization rich solution economic benefits and social benefits desorption technique and system
CN105985814B (en) * 2015-02-09 2019-02-01 上海同特化工科技有限公司 The treatment process of hydrogen sulfide, hydrogen cyanide and ammonia is removed from coal gas
CN104726141A (en) * 2015-03-27 2015-06-24 山东钢铁股份有限公司 Method for ammonia removal of coke oven gas
CN105271305A (en) * 2015-09-29 2016-01-27 山东钢铁股份有限公司 Method for treating ammonia water obtained after ammonia distillation of residual ammonia water
CN106673014B (en) * 2016-12-29 2018-11-23 天津市创举科技股份有限公司 A kind of coke oven gas desulfurization Study of Deamination is for ammonium hydroxide technique

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