CN1374148A

CN1374148A - Integrated liquid column spraying fume desulfurizing and dust eliminating method and apparatus

Info

Publication number: CN1374148A
Application number: CN 01109634
Authority: CN
Inventors: 项光明; 姚强; 陈昌和; 徐旭常; 李定凯; 刘惠永; 孙俊民; 廖洪强; 何苏浩; 佟会玲; 李彦; 祁海鹰; 由长福; 沈伯雄
Original assignee: Tsinghua University; Qinghua Tongfang Co Ltd
Current assignee: TONGFANG ENVIRONMENT CO Ltd; Tsinghua University
Priority date: 2001-03-14
Filing date: 2001-03-14
Publication date: 2002-10-16
Anticipated expiration: 2021-03-14
Also published as: CN1229168C

Abstract

A liquid column injection flue gas desulfurization and dust removal integrated method and device thereof. Its characteristic is that the flue gas desulfurization and dust removal are integrated, the flue gas is sent tangentially to the middle and lower part of the reaction tower, so that the smoke and dust in the flue gas are enriched on the wall of the reaction tower, and the upper part of the reaction tower is injected with water to clean out the dust in the flue gas. Dust; there is a nozzle in the reaction tower to make the flue gas mix, react and form calcium sulfite and calcium sulfate. Through forced oxidation, the concentrated mortar is discharged, and the thinner mortar and unreacted and newly added calcium-based desulfurizer are transported to the nozzle and sprayed again. Compared with the prior art, the present invention has small footprint, low investment and operation cost, and high desulfurization and dust removal efficiency.

Description

A kind of integrated liquid column spraying fume desulfurizing and dust eliminating method and device thereof

The invention belongs to flue-gas dust-removing and desulfurization integrated technology field, relate in particular to the technique device that removes of sulfur in smoke that pulverized-coal fired boiler, grate firing boiler or other combustion apparatus discharge and solid particle.

In the middle of the present coal-burned industrial boiler and station boiler, quite a few adopts water film dust removal device.The flue gas that combustion apparatus is discharged is first by a convergent increaser (claiming Venturi tube again) in flue, entering the back from the cylinder lower tangential of water dust scrubber then upwards flows and rotates, spray into current simultaneously, form adherent current at the cylindrical shape water dust scrubber, solid particle enters adherent current under centrifugal action, thereby washes the dust that is contained in the flue gas that flows from bottom to top.Adopt the efficient of water film dedusting generally to be lower than 85%, and, there is not desulfurizing function, can not satisfy requirement on environmental protection.Because the pollution of sulfur dioxide is the focus of world many countries environmental protection always, the flue gas desulfurization technique that various countries successively develop has reached kind more than 200.But, can be applied to the industrial kind more than ten of having only.Up to the present, in the Industrial Boiler and station boiler of fire coal, adopt the wet process of FGD technology more than 90%, wherein based on limestone-gypsum method.Though this method desulfuration efficiency is higher, be the effective method of flue gas desulfurization.But there is system's relative complex usually, the shortcoming that floor space is bigger, and fouling and clogging appear easily, cause initial cost and operating cost all higher.Chinese patent for this reason, the patent No. is CN1238233, discloses a kind of process for integrating dust removal with desulfurization by water film and system, it can overcome above-mentioned shortcoming well.Its main feature is that existing water dust scrubber is transformed, increase the injection apparatus of desulfurizer slurry, in this process, fully react with sulfur dioxide in flue gas, realize high-efficiency desulfurization and prevent fouling and obstruction, while is owing to the increase of fluid column has been strengthened the washing of center dust, nor the meeting transition increases the flue gas resistance of system.This patented technology has obtained good application.But, because this patented technology is that the water dust scrubber of routine is transformed, must increase auxiliary equipment such as oxidation pond in addition, cause floor space big, and, need the equipment changed more in the transformation process, complex process.

Purpose of the present invention and task are deficiency and the defectives that exists in the existing and above-mentioned improved water dust scrubber technology, provide a kind of liquid to annotate spraying fume desulfurizing and dust integrated approach and device thereof, under the prerequisite that it is little at occupation area of equipment and the investment operating cost is low, dedusting and desulfur technology are integrated in one, can access higher efficiency of dust collection, desulfuration efficiency, sorbent utilization and desulfurization product oxygenation efficiency.

In order to reach above-mentioned goal of the invention, technical scheme of the present invention realizes as follows:

A kind of liquid is annotated the spraying fume desulfurizing and dust integrated approach, the steps include:

1. the flue gas of discharging in the combustion apparatus is tangentially sent into middle and lower part in the desulfurization and dedusting reaction tower, make flue dust in the flue gas be enriched in the wall of reaction tower, and, form top-down adherent moisture film at reaction tower internal upper part injection current, wash the dust that is contained in the flue gas that flows from bottom to top.

2. by being arranged on the liquid column-spraying device at middle part in the reaction tower, at the inner fluid column that forms earlier from bottom to top of reaction tower, form the drop of adverse current from top to bottom again, make it mix, react with from bottom to top flue gas and form calcium sulfite and calcium sulfate, the dust in flue gas flows to down with liquid and discharges afterwards.

3. the calcium sulfite of reaction back generation and calcium sulfate flow into the oxidation trough of reaction tower bottom with soot dust granule and water, by being calcium sulfate with calcium sulfite oxidation behind the forced oxidation, concentrated, the precipitation process of warp in the portion of concentrating, denseer mortar is disposed to the lime-ash treatment system, mortar that will be rarer and unreacted calcium-based desulfurizing agent and initiate desulfurizing agent completely are recycled pump with current and are delivered to the liquid column-spraying device and spray once more after stirring.

Realize the device of above-mentioned integrated liquid column spraying fume desulfurizing and dust eliminating method, it comprises reaction tower, oxidation fan and circulating pump.Its design feature is that the top of described reaction tower and the middle part of its outer wall are respectively equipped with exhanst gas outlet and smoke inlet.Top in the reaction tower is provided with demister, is provided with the female pipe of the moisture film that can form adherent moisture film below the demister.Demister, the female Guan Jun of moisture film connect feed pipe outward.Middle and lower part in the reaction tower is provided with the injection apparatus that can spray fluid column.Be furnished with nozzle on the injection apparatus, the bottom to reaction tower below the injection apparatus is made as oxidation trough, and the top of oxidation trough and middle part are respectively equipped with the pulp-inlet pipe and the portion of concentrating.The bottom of oxidation trough is provided with interface and pump entry joins, and the feed pipe for mortar of circulating-pump outlet and injection apparatus joins.Be provided with agitator in the oxidation trough.The bottom of oxidation trough is provided with air blast, and the outer oxidation fan of air blast and reaction tower joins.

According to above-mentioned technical scheme, the female pipe ring of described moisture film is around the reaction tower internal perisporium; Described injection apparatus is made up of the branch jet pipe of many parallel arrangements, is furnished with nozzle on each minute jet pipe, all joins with feed pipe for mortar.

The present invention has the following advantages and useful effect compared with the prior art:

(1) because the present invention has adopted desulphurizing and dust-removing integral and absorption reaction district zoneofoxidation integrated, reduces the investment and the operating cost of equipment significantly, and saved land area, reduced the complexity of technology and device thereof.

(2) this device adopts flue gas tangentially to enter reaction tower, produces eddy flow and utilizes moisture film to carry out dedusting.Because desulfurization slurry forms good gas-liquid mixed attitude in reactor, the drop that contains desulfurizing agent is fully contacted with flue gas, strengthened making dust removing effects better than general water film dedusting to the removing of flue dust.

(3) atomizing effect that this device is good contacts with gas-liquid and makes sulfur in smoke be removed effectively, owing to remove the grit itself that gets off and just desulphurization reaction had good facilitation, so this device reaches high desulfuration efficiency than general desulfurization reaction tower is easier.Recycling repeatedly of desulfurization slurry makes the higher utilization rate that desulfurizing agent can reach, and the forced oxidation in oxidation trough then can guarantee the high oxidation rate of desulfurization product.

(4) this device has solved system's fouling and blockage problem preferably in efficient desulfurizing and dust collecting.

The present invention will be further described with reference to accompanying drawing below in conjunction with the step of the inventive method and embodiment.

Fig. 1 is an apparatus structure connection layout of implementing the inventive method;

Fig. 2 is that the A-A of Fig. 1 is to sectional structure chart.

The concrete steps of the inventive method are: (1) tangentially sends the flue gas of discharging in the combustion apparatus into middle and lower part in the desulfurization and dedusting reaction tower, make flue dust in the flue gas be enriched in the wall of reaction tower, and at reaction tower top injection current, form top-down adherent moisture film, wash the dust that is contained in the flue gas that flows from bottom to top; (2) by being arranged on the liquid column-spraying device at middle part in the reaction tower, at the inner fluid column that forms earlier from bottom to top of reaction tower, form the drop of adverse current from top to bottom again, it is mixed with from bottom to top flue gas, reaction also forms calcium sulfite and calcium sulfate, and the dust in flue gas flows to down with liquid and discharges afterwards; (3) calcium sulfite of reaction back generation and calcium sulfate flow into the oxidation trough of reaction tower bottom with soot dust granule and water, by being calcium sulfate with calcium sulfite oxidation behind the forced oxidation, concentrated, the precipitation process of warp in the portion of concentrating, denseer mortar is disposed to the lime-ash treatment system, mortar that will be rarer and unreacted calcium-based desulfurizing agent and initiate desulfurizing agent completely are recycled pump with current and are delivered to the fluid column jet pipe and spray once more after stirring.

Referring to Fig. 1 and Fig. 2, implement the device of the inventive method, it comprises reaction tower 7, oxidation fan 14 and circulating pump 9.The top of described reaction tower 7 and the middle part of its outer wall are respectively equipped with exhanst gas outlet 4 and smoke inlet 2, and the tops in the reaction tower 7 are provided with demister 5, are provided with the female pipe 3 of the moisture film that is looped around reaction tower 7 internal perisporiums that can form adherent moisture film below the demister 5.Demister 5, all outer feed pipe 6 that connects of the female pipe 3 of moisture film.Middle and lower part in the reaction tower 7 be provided with can spray fluid column, by the injection apparatus 8 that the branch jet pipe of many parallel arrangements is formed, be furnished with nozzle 15 on the injection apparatus 8, all join with feed pipe for mortar.Bottom to reaction tower 7 below the injection apparatus 8 is made as oxidation trough 11.The top of oxidation trough 11 and middle part are respectively equipped with pulp-inlet pipe 1 and concentrate portion 10.The bottom of oxidation trough 11 is provided with interface and circulating pump 9 inlets join.The feed pipe for mortar of circulating pump 9 outlets and injection apparatus 8 joins.Be provided with agitator 13 in the oxidation trough 11, the bottom of oxidation trough 11 is provided with air blast 12, and the oxidation fan 14 outside air blast 12 and the reaction tower 7 joins.

When this device used, the flue gas of discharging from combustion apparatus rotated after smoke inlet 2 tangentially enters reaction tower 7.Water from the industrial water supply device supplies water in female pipe 3 of moisture film and demister 5 respectively through feed pipe 6.The water that enters the female pipe 3 of moisture film forms adherent moisture film in reaction tower 7, wash the dust that is contained in the flue gas that flows from bottom to top.Simultaneously, sufficient desulphurization reaction takes place with the slurries that injection apparatus 8 sprays in priority in the process that flue gas moves upward.Flue gas behind the desulphurization reaction carries out the demist depositing dust through demister 5 to be handled, and discharges by exhanst gas outlet 4.Slurries with desulfurizing function are supplemented in the oxidation trough 11 by pulp-inlet pipe 1 by apparatus for preparing desulphurizing agent.Deliver to injection apparatus 8 by circulating pump 9 by feed pipe for mortar.Accessory substance calcium sulfite behind the desulphurization reaction comes downwards to the oxidation trough 11 that is arranged in reaction tower 7 bottoms, and the air generation oxidation reaction with also carrying by oxidation fan 14 from air blast 12 generates calcium sulfate (gypsum).Calcium sulfate drains into the desulfurization product treating apparatus in concentrated portion 10 through concentrated, post precipitation.In order to keep desulfurization product in tower, not deposit, be provided with agitating device 13 in the oxidation trough 11, air-blowing device 12 also plays stirring action.

Claims

1. A liquid column injection type flue gas desulfurization and dust removal integrated method, its steps are:

(1) The flue gas discharged from the combustion equipment is sent tangentially to the middle and lower part of the desulfurization and dust removal reaction tower, so that the dust in the flue gas is enriched on the wall of the reaction tower, and water is injected into the upper part of the reaction tower to form a top-down The wall-attached water film below cleans away the dust contained in the flue gas flowing from bottom to top;

(2) Through the liquid column injection device installed in the middle of the reaction tower, a bottom-up liquid column is first formed inside the reaction tower, and then a top-down countercurrent liquid drop is formed to make it merge with the bottom-up smoke The gas mixes, reacts, and forms calcium sulfite and calcium sulfate, which are then discharged downward with the liquid flow together with the dust in the flue gas;

(3) The calcium sulfite and calcium sulfate generated after the reaction flow into the bottom of the reaction tower with the soot particles and water, and the calcium sulfite is oxidized to calcium sulfate after forced oxidation. After concentration and precipitation in the concentration part, the concentrated mortar is It is discharged to the ash and slag treatment system. After stirring the thinner mortar, unreacted calcium-based desulfurizer and newly added desulfurizer, it is transported to the liquid column injection device by the circulating pump along with the water flow and sprayed again.

2. realize the device of claim 1 said liquid column injection type flue gas desulfurization and dust removal integrated method, it comprises reaction tower (7), oxidation fan (14), circulation pump (9), it is characterized in that: described reaction tower ( 7) The top of the top and the middle part of the outer wall are respectively provided with a flue gas outlet (4) and a flue gas inlet (2). A water film main pipe (3) capable of forming a wall-attached water film is provided, and the mist eliminator (5) and the water film main pipe (3) are all externally connected to the water supply pipe (6), and the middle and lower parts of the reaction tower (7) are provided with The injection device (8) that can spray liquid column is arranged, and nozzle (15) is arranged on the injection device (8), is set as oxidation tank (11) to the bottom of reaction tower (7) below the injection device (8), and oxidation tank The top and middle part of (11) are respectively provided with inlet pipe (1) and concentrator (10), and the bottom of oxidation tank (11) is provided with interface and joins with circulation pump (9) inlet, and circulation pump (9) outlet is connected with The slurry delivery pipes of the injection device (8) are connected, the oxidation tank (11) is provided with an agitator (13), the bottom of the oxidation tank (11) is provided with a blower (12), and the blower (12) and the reaction tower (7) Outer oxidation fan (14) is connected.

3. The device according to claim 2, characterized in that: said water film main pipe (3) surrounds the inner peripheral wall of the reaction tower (7).

4. according to the described device of claim 2 or 3, it is characterized in that: described spraying device (8) is made up of the sub-spray pipes of a plurality of parallel arrangements, and each sub-spray pipe is equipped with nozzles (15) that are all connected with the delivery pipes. The pulp pipes are connected.