CN110237682A - A kind of coal-fired flue-gas complementary energy recycling spray column with load adaptability - Google Patents

A kind of coal-fired flue-gas complementary energy recycling spray column with load adaptability Download PDF

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Publication number
CN110237682A
CN110237682A CN201910442228.9A CN201910442228A CN110237682A CN 110237682 A CN110237682 A CN 110237682A CN 201910442228 A CN201910442228 A CN 201910442228A CN 110237682 A CN110237682 A CN 110237682A
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China
Prior art keywords
gas
coal
spraying
lower section
spray column
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CN201910442228.9A
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Chinese (zh)
Inventor
胡鹏龙
边福忠
敖文志
吕菲
毛敏捷
金峰武
陈国军
夏振东
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GUIHUI ENVIRONMENTAL PROTECTION NEW ENERGY CO Ltd
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GUIHUI ENVIRONMENTAL PROTECTION NEW ENERGY CO Ltd
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Priority to CN201910442228.9A priority Critical patent/CN110237682A/en
Publication of CN110237682A publication Critical patent/CN110237682A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation 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
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/343Heat recovery
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation 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
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/46Removing components of defined structure
    • B01D53/48Sulfur compounds
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation 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
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/74General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/77Liquid phase processes
    • B01D53/78Liquid phase processes with gas-liquid contact

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Treating Waste Gases (AREA)

Abstract

The invention belongs to flue gas heat recovery and purification techniques fields, and in particular to a kind of coal-fired flue-gas complementary energy recycling spray column with load adaptability, including tower body, the top of tower body is equipped with gas outlet, the bottom of tower body is equipped with air inlet, and in the tower body, the lower section of gas outlet is equipped with demister;The lower section of demister is equipped with spraying layer, the spraying layer includes liquid distribution trough, the lower section of liquid distribution trough is spraying zone, the lower section of spraying zone is equipped with drip tray, it is parallel with flue gas flow direction in spraying zone to be equipped with several partitions, spraying zone is divided into several independent spraying zones by partition, is equipped with the gas baffle that can be stirred below each independent spraying zone.This spray column controls the opening and closing of independent spraying zone in spraying layer according to flue gas flow, and then controls the subregion that liquid distribution trough is opened, and reduces spray water flow, and concentrated area exchanges heat, and heat exchange efficiency is higher.

Description

A kind of coal-fired flue-gas complementary energy recycling spray column with load adaptability
Technical field
The invention belongs to flue gas heat recovery and purification techniques fields, and in particular to a kind of fire coal with load adaptability Flue gas complementary energy recycles spray column.
Background technique
China is maximum coal production and country of consumption in the world, and take coal as the economic giant of main non-renewable energy, Power generation and the rapid development of central heating industry are so that coal in China consumption sustainable growth.Fire coal generates a large amount of oxysulfides, therefore The coal unit in China is mounted with wet desulfurization system mostly at present, and according to the environmental regulations of different regions, general flue gas passes through Through smoke stack emission or wet stack after wet electrical dust precipitator, flue gas at this time is wet saturation state, carries a large amount of water and steams Gas.
China proposes water-saving requirement in development plan, meanwhile, it also proposed low product in promotion for energy conservation and environmental protection Industrial low grade residual heat resource innovation, is applied to the policies such as concentrated supply of heating in the city by position waste heat overbottom pressure resource recycling. The promotion of coal-burning boiler energy-saving Environmental-protection comprehensive, consumption of coal decrement substitution, urbanization energy conservation upgrading will be organized and implemented in next step Deng energy saving key project.Currently, coal-fired flue-gas discharged after wet desulphurization the main problems are as follows:
Due to the operational characteristic of wet desulphurization, flue gas and slurries counter current contacting progressively reach wet saturation state, typical at this time Operating condition is 52 DEG C of smoke temperature or so, and containing water vapor amount is about 112g/Nm3 and containing a large amount of desulfurization products, including sulfate, desulfurization Agent, nitrate and chloride ion etc..This part vapor and desulfurization product, which are discharged into atmosphere, will cause " white plume ", " gypsum Rain " phenomenon influences environment and visual perception around chimney.
The water vapour content of existing flue gas emission mode is higher, it is meant that the waste of large quantity of moisture and low temperature exhaust heat.One side Face, sulfur removal technology water consumption itself is huge, needs that process water is continuously replenished;On the other hand, enterprise is eager to improve boiler thermal effect Rate, and some areas do not allow new construction of coal-fired boiler, need to utilize low temperature exhaust heat to greatest extent.
There is the variation of exhaust gas volumn caused by how adapting to plant area's load, heat supply network caused by season in existing spray heat transfer technology Return water temperature variation issue.There are 20%~105% load adaptabilities for absorption heat pump itself, but only certainly by heat pump Body de-regulation has that regulative mode is single.Unit Commitment is frequent, it is long to stablize the time, and heat pump unit is wanted in design There are larger surpluses.In addition, whole water spray remains unchanged, pump consumption is big, and heat pump entrance heat source coolant-temperature gage reduces, no Conducive to the raising of whole efficiency.
Summary of the invention
The one side of the disclosure provides a kind of coal-fired flue-gas complementary energy recycling spray column with load adaptability, solves Only by heat pump itself de-regulation, it is single that there are regulative modes;And Unit Commitment is frequent, the stable time is long, and heat pump machine Group will there are larger surpluses in design;It is remained unchanged with whole water spray, pump consumption is big, heat pump entrance heat source water temperature The problems such as degree reduces, and is unfavorable for the raising of whole efficiency.
To achieve the above object, the present invention adopts the following technical scheme that, the present invention includes tower body, and the top of tower body is equipped with Gas outlet, the bottom of tower body are equipped with air inlet, and in the tower body, the lower section of gas outlet is equipped with demister;It is set below demister There is spraying layer, the spraying layer includes liquid distribution trough, and the lower section of liquid distribution trough is spraying zone, and the lower section of spraying zone is equipped with Drip tray, spraying zone is interior parallel with flue gas flow direction equipped with several partitions, and spraying zone is divided into several independently to spray by partition Area is drenched, is equipped with the gas baffle that can be stirred below each independent spraying zone, when gas baffle is closed, flue gas will be from it He is discharged independent spraying zone.
Further, the liquid distribution trough includes several sparge pipes, and the lower section of sparge pipe is equipped with nozzle, sparge pipe It is connected with the water inlet on tower body side wall.
Further, the liquid distribution trough marks off the independent partitions of quantity identical as spraying zone independent in spraying zone, And the independent spraying zone of each subregion and lower section matches, each independent partitions independent control.
Further, the gas baffle is electric rotating plate.
Further, the drip tray is equipped with water outlet, and water outlet is connected with the outlet pipe on tower body side wall.
Further, the side at the top of tower body is arranged in the gas outlet.
A kind of flue gas complementary energy recovery system, including it is above-mentioned with load adaptability coal-fired flue-gas complementary energy recycling spray column, Condensate tank, heat exchanger, absorption heat pump, the outlet pipe of the coal-fired flue-gas complementary energy recycling spray column with load adaptability One branch is connected with the hot end water inlet of heat exchanger, another branch is connected with the water inlet of condensate tank, heat exchanger Hot end water outlet be connected by water pump with liquid distribution trough, the water outlet of condensate tank by water pump and demister into The mouth of a river is connected, and the cold water end of heat exchanger is connected with absorption heat pump.
Compared with the prior art, the invention has the following advantages:
(1) energy saving and heat exchange efficiency is higher.The opening and closing of independent spraying zone in spraying layer is controlled according to flue gas flow, in turn The subregion that liquid distribution trough is opened is controlled, spray water flow is reduced, concentrated area exchanges heat, and heat exchange efficiency is higher.
(2) water-saving.The technology takes heat by vapor in condensation flue gas, this part vapor forms condensed water, condensed water It can be used for desulphurization system moisturizing, it is significant for the area of more water shortage.
(3) white, further purifying smoke is taken off.Part vapor and desulfurization product in flue gas are collected into shower water, subtracted " white plume ", " gypsum rain " phenomenon caused by being gently discharged into atmosphere, flue gas can reach ultra-clean discharge.
Detailed description of the invention
Fig. 1 is overall structure diagram according to one aspect of the disclosure;
Fig. 2 is spray schematic diagram of a layer structure according to one aspect of the disclosure;
Fig. 3 is flue gas complementary energy recovery system structural schematic diagram according to one aspect of the disclosure;
In figure: 1- tower body, the gas outlet 2-, 3- demister, 4- spraying layer, 401- liquid distribution trough, 402- drip tray, 403- partition, 404- independence spraying zone, 405- electric rotating plate, 5- air inlet, 6- condensate tank, 7- heat exchanger, 8- absorption type heat Pump.
Specific embodiment
The present invention is further explained below in conjunction with specific embodiment, but the not limitation present invention, is said Structure, ratio, size depicted in bright book attached drawing etc., only to cooperate the revealed content of specification, for being familiar with this skill The personage of art understands and reads, and is not intended to limit the invention enforceable qualifications, therefore does not have technical essence meaning Justice, the modification of any structure, the change of proportionate relationship or the adjustment of size, do not influence the effect of present invention can be generated and Under the purpose that can reach, should all still it fall in the range of disclosed technology contents can cover.Meanwhile this theory Cited such as "upper", "lower", "front", "rear", " centre " term in bright book are merely convenient to being illustrated for narration, rather than To limit the scope of the invention, relativeness is altered or modified, under the content of no substantial changes in technology, when Also it is considered as the enforceable scope of the present invention.
As shown in Figure 1, the present apparatus includes tower body 1, the top of tower body 1 is equipped with gas outlet 2, and the bottom of tower body is equipped with 5 air inlets Mouthful, the lower section of gas outlet 2 is equipped with demister 3;The lower section of demister 3 is equipped with spraying layer 4, and spraying layer 4 includes liquid distribution trough 401, the lower section of liquid distribution trough 401 is spraying zone, and the lower section of spraying zone is equipped with drip tray 402, is equipped with cross phase in spraying zone Two partitions 403 handed over, crosspoint are the center of spraying zone, and spraying zone is divided into four same big by the partition that two intersect Small independent spraying zone 404, the lower section of each independent spraying zone 404 are equipped with electric rotating plate 405, and electric rotating plate 405 is for controlling The trend of tobacco curing gas, plays the role of shunting.Liquid distribution trough 401 is equally separated out the independence point of four same sizes Area, each independent partitions can independent controls.
Liquid distribution trough 404 includes several sparge pipes, and the lower section of sparge pipe is equipped with nozzle, sparge pipe and tower body side wall On water inlet be connected.
Shower water after heat exchange is picked out from drip tray, and dust and desulfurization product are contained in water, as plate heat exchanger heat End uses after plate heat exchanger exchanges heat as circulated sprinkling water.Plate heat exchanger cold end is connect with absorption heat pump, is utilized Absorption heat pump takes out heat, heats heat supply network return water.For example, the coal-powder boiler of a 50t/h, by flue gas after desulfurization by 52.5 DEG C 38 DEG C are down to, water content is down to 53 g/Nm3 by 112g/Nm3, can recycle the water of 4.7t/h and the heat of 3.3MW, boiler Efficiency can be improved 9.4%.This partial heat is incorporated to heat supply network after upgrading by absorption heat pump, recycling is a large amount of low-grade remaining Heat.
In the case where load is low, exhaust gas volumn is small, part electric rotating plate 405 is closed, electric rotating plate of the flue gas from unlatching is made 405 sides and shower water carry out contact heat-exchanging (adverse current).At this point, being still able to maintain in 404 region of independent spraying zone of certain unlatchings For reasonable flue gas flow rate, sprinkle density (optimum operation condition), tower heat exchange efficiency itself is highest, and tower pressure drop is in design model In enclosing.Meanwhile under the premise of guaranteeing that heat pump entrance heat source water is temperature-resistant, water spray can be reduced, be conducive to water pump reduction Power consumption.
For example, certain 70MW boiler system, spray column are designed according to above-described embodiment, at full capacity under it is about recyclable 25.2Gj/h.Three layers of spray head of longitudinal design (about 60 spray heads) reach design area coverage about 24m2, it is ensured that without spray in tower Drench dead angle, sprinkle density can between 0~15L/Nm3 flexible conversion.To embody load adaptability, in system power 30MW, Exhaust gas volumn is reduced to original 43% at this time, closes spraying zone two therein independent spraying zones 404 and (closes independent spraying zone phase The subregion of associated gas baffle, liquid distribution trough), to guarantee that tower dynamic loading is stablized, closed in diagonal line, flue gas flow rate ratio Design value is slightly lower, about 1.72m/s, and liquid-gas ratio control is in 2.5L/Nm3, (water spray is controlled by electromagnetic valve and pipeline).Spray Water drenching flow-reduction 60% can save about 15 kilowatt hour of electrical power consumption of water pump.Source heat pump heat coolant-temperature gage keeps design value, and flow reduces, Conveniently regulating and controlling, heat exchange efficiency are higher.
As shown in Fig. 2, a kind of flue gas complementary energy recovery system, including the above-mentioned coal-fired flue-gas complementary energy with load adaptability Spray column, condensate tank 6, heat exchanger 7, absorption heat pump 8 are recycled, the coal-fired flue-gas complementary energy with load adaptability recycles spray A branch for drenching the outlet pipe of tower is connected with the hot end water inlet of heat exchanger 7, another branch and condensate tank 6 into The mouth of a river is connected, and the hot end water outlet of heat exchanger 7 is connected by water pump with liquid distribution trough 401, the water outlet of condensate tank 7 Mouth is connected by water pump with the water inlet of demister 3, and the cold water end of heat exchanger 7 is connected with absorption heat pump 8.
It although an embodiment of the present invention has been shown and described, for the ordinary skill in the art, can be with A variety of variations, modification, replacement can be carried out to these embodiments without departing from the principles and spirit of the present invention by understanding And modification, the scope of the present invention is defined by the appended.

Claims (7)

1. the coal-fired flue-gas complementary energy with load adaptability recycles spray column, including tower body, the top of tower body is equipped with gas outlet, tower The bottom of body is equipped with air inlet, it is characterised in that: in the tower body, the lower section of gas outlet is equipped with demister;
The lower section of demister is equipped with spraying layer, and the spraying layer includes liquid distribution trough, and the lower section of liquid distribution trough is spraying zone, The lower section of spraying zone is equipped with drip tray, and spraying zone is interior parallel with flue gas flow direction equipped with several partitions, and partition distinguishes spray Several independent spraying zones are cut into, are equipped with the gas baffle that can be stirred below each independent spraying zone.
2. the coal-fired flue-gas complementary energy according to claim 1 with load adaptability recycles spray column, it is characterised in that: institute Stating liquid distribution trough includes several sparge pipes, and the lower section of sparge pipe is equipped with nozzle, the water inlet on sparge pipe and tower body side wall It is connected.
3. the coal-fired flue-gas complementary energy according to claim 1 with load adaptability recycles spray column, it is characterised in that: institute State the independent partitions that liquid distribution trough marks off quantity identical as spraying zone independent in spraying zone, and each subregion and lower section is only Vertical spraying zone matches, each independent partitions independent control.
4. the coal-fired flue-gas complementary energy according to claim 1 with load adaptability recycles spray column, it is characterised in that: institute Stating gas baffle is electric rotating plate.
5. the coal-fired flue-gas complementary energy according to claim 1 with load adaptability recycles spray column, it is characterised in that: institute Drip tray is stated equipped with water outlet, water outlet is connected with the outlet pipe on tower body side wall.
6. the coal-fired flue-gas complementary energy according to claim 1 with load adaptability recycles spray column, it is characterised in that: institute State the side that the top of tower body is arranged in gas outlet.
7. a kind of flue gas complementary energy recovery system, it is characterised in that: including the fire coal described in claim 1 with load adaptability Flue gas complementary energy recycles spray column, condensate tank, heat exchanger, absorption heat pump, and the coal-fired flue-gas complementary energy with load adaptability is returned A branch for receiving the outlet pipe of spray column is connected with the hot end water inlet of heat exchanger, another branch and condensate tank into The mouth of a river is connected, and the hot end water outlet of heat exchanger is connected by water pump with liquid distribution trough, and the water outlet of condensate tank passes through Water pump is connected with the water inlet of demister, and the cold water end of heat exchanger is connected with absorption heat pump.
CN201910442228.9A 2019-05-24 2019-05-24 A kind of coal-fired flue-gas complementary energy recycling spray column with load adaptability Pending CN110237682A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113230871A (en) * 2021-05-08 2021-08-10 西安热工研究院有限公司 Spraying layer partition adjusting desulfurization absorption tower based on concentration field distribution at outlet of absorption tower
CN115193202A (en) * 2022-09-19 2022-10-18 航天氢能沧州气体有限公司 Energy-saving environment-friendly synthetic gas washing tower

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102728187A (en) * 2012-07-27 2012-10-17 北京国能中电节能环保技术有限责任公司 Absorption tower of multi-furnace one-tower desulfurizer
WO2017036199A1 (en) * 2015-09-01 2017-03-09 同济大学 Method for inhibiting the generation of dioxins in the solid waste incineration flue gas
CN207539920U (en) * 2017-10-31 2018-06-26 中国华能集团清洁能源技术研究院有限公司 A kind of system using absorption heat pump Mist heat recovering
CN210786836U (en) * 2019-05-24 2020-06-19 国惠环保新能源有限公司 Coal-fired flue gas complementary energy recovery spray tower and flue gas complementary energy recovery system with load adaptability

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102728187A (en) * 2012-07-27 2012-10-17 北京国能中电节能环保技术有限责任公司 Absorption tower of multi-furnace one-tower desulfurizer
WO2017036199A1 (en) * 2015-09-01 2017-03-09 同济大学 Method for inhibiting the generation of dioxins in the solid waste incineration flue gas
CN207539920U (en) * 2017-10-31 2018-06-26 中国华能集团清洁能源技术研究院有限公司 A kind of system using absorption heat pump Mist heat recovering
CN210786836U (en) * 2019-05-24 2020-06-19 国惠环保新能源有限公司 Coal-fired flue gas complementary energy recovery spray tower and flue gas complementary energy recovery system with load adaptability

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113230871A (en) * 2021-05-08 2021-08-10 西安热工研究院有限公司 Spraying layer partition adjusting desulfurization absorption tower based on concentration field distribution at outlet of absorption tower
CN115193202A (en) * 2022-09-19 2022-10-18 航天氢能沧州气体有限公司 Energy-saving environment-friendly synthetic gas washing tower

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Application publication date: 20190917