Remove the device of sulfur dioxide in the waste gas
Technical field
The present invention relates to a kind of device that removes sulfur dioxide in the waste gas.
Background technology
Usually in discharging tail gas such as refining miner industry, sulfuric acid industry or fire coal, oil burning boiler, all contain SO
2Gas.Even the SO of trace
2Content because discharge capacity is huge, also can do great damage to environment and ecology.It is reported, China become continue America, Europe after be subjected to acid rain to endanger serious area the most, the sheet forest, soil ruined.China explicitly calls for, and newly going up power plant must supporting flue gas desulphurization unit, and the power plant that requires existing discharging to exceed standard must install the desulfurization facility before the end of the year 2010, wherein goes into operation more than 20 years or installed capacity below 100,000 kilowatts, time limit transformation or close down.Meanwhile, stipulate 1 kilogram of SO of every discharging
2Charge 0.63 yuan, the management of environmental protection special fund is directly included in this charge in, is used to curb environmental pollution.In order to encourage enterprise to reduce discharging, to put into effect electrovalence policy in June, 2006 and represent, the every kilowatt hour of newly-built and existing desulfurization unit rate for incorporation into the power network all improves 0.015 yuan.From the state macro-control policy, the supporting exhuast gas desulfurization facility of relevant enterprise is imperative.
Existing a kind of application number is 200710130218.9 and is called that the Chinese invention patent of " by the process units of waste gas sulfate ammonium " discloses a kind of structure, and its structure be three functional areas of main branch: deamination district, desulfurization zone and oxidizing and crystallizing district.It is provided with the purification exhanst gas outlet in desulfurizing tower cat head center; Be provided with gas, the liquid separating member that comprises the flushing water distributor at the tower body internal upper part; The deamination circulating absorption solution distributor that is connected with the import of deamination circulating absorption solution is set below gas, liquid separating member; Below deamination circulating absorption solution distributor, the deamination district is set; The desulphurization circulating absorption liquid distributor that is connected with the import of desulphurization circulating absorption liquid is set below the deamination district; Below desulphurization circulating absorption liquid distributor, desulfurization zone is set; Absorption liquid overflow outlet is set on tower body; Below the overflow outlet, the oxidizing and crystallizing district is set.The characteristics of this equipment are that investment is low, and energy consumption is little, and gas treatment ability is big, and the efficient height is fit to heavy industrialization and uses.But its shortcoming is: 1, waste gas cooling is that gas-liquid in the absorption tower is divided in the absorber portion of device and carried out, be the water that on gas-liquid distributor, sprays of waste gas or absorption liquid counter current contacting and be cooled, and cooling water adds from the desulfurizing tower top, mix in tower with absorption liquid, cause: a, absorption liquid are diluted; It is higher that b, EGT enter the temperature of desulfurizing tower, if make waste gas be reduced to lower temperature by absorption liquid (or mixture of water and absorption liquid) counter current contacting, can only strengthen the height of desulfurizing tower, perhaps increases liquid-gas ratio.More than two all can cause its assimilation effect to descend, perhaps cause equipment investment to strengthen and increase operating cost.2, the absorption liquid distributor of this structure is the liquid spray thrower, be about to absorption liquid through spray head do to spray and with, upwards the gas that flows is upwards to flow through one side madial wall in the absorption tower, this structure is for forming the gas-liquid bias current, thereby make distribution of gas inhomogeneous, cause contact area to reduce, absorptivity is low; Also have, gas-liquid separator can make gas rising resistance increase because of rising by bias current, and operating efficiency is descended.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of device that removes sulfur dioxide in the waste gas at above-mentioned prior art present situation, it concentrates on waste gas cooling, concentrated absorption liquid, desulfurization, oxidizing process in the absorption tower and carries out, make full use of the device space, save the area, simplify technological process, reduce equipment investment, and waste gas is evenly distributed in the absorption tower, desulfurization reduces production costs fully.
The present invention solves the problems of the technologies described above the technical scheme that is adopted: this removes the device of sulfur dioxide in the waste gas, include the absorption tower, the side, middle part on absorption tower is provided with the waste gas inlet port, in the absorption tower, be provided with gas-liquid distributor, be provided with the clean gas floss hole at the top on absorption tower, concentrate zoneofoxidation and be provided with absorption liquid in the bottom on absorption tower, concentrating zoneofoxidation is connected with the extraneous air hose that is provided with air-blaster by pipeline, gas-liquid distributor is connected with the absorption liquid of concentrated zoneofoxidation through circulating pump by pipeline, it is characterized in that: described waste gas inlet port is connected with cooling device in the absorption tower, the gas vent of this cooling device is connected with concentrated zoneofoxidation, concentrate zoneofoxidation and absorption tower intracavity inter-connection, and concentrated zoneofoxidation flows to collection place of ammonium sulfate finished product by the pipeline that is provided with valve through the extraction pump.
As improvement, the structure of described cooling device can be preferably: be provided with the cooling cylindrical shell in the absorption tower, it in the cooling cylindrical shell helical form annular chamber of coiling downwards, described waste gas leads to annular chamber from the waste gas inlet port, the gas outlet of annular chamber is connected with concentrated zoneofoxidation, be provided with spray thrower in annular chamber, spray thrower is connected with absorption liquid or cooling fluid by the circulating pump of pipeline through the outside, absorption tower.
Improve again, described annular chamber is provided with dedusting mechanism in it, the structure choice of this dedusting mechanism is: the toroidal frame that is provided with vertical setting in annular chamber, be provided with at the top of toroidal frame and prevent that liquid from entering the liquid barrier of toroidal frame inner chamber, have in the side that is positioned at toroidal frame and can make waste gas enter the air admission hole of toroidal frame inner chamber, the toroidal frame inner chamber is connected with concentrated zoneofoxidation, in annular chamber, be provided with and prevent that absorption liquid from entering the clamping plate that concentrate zoneofoxidation, absorption liquid in the described annular chamber is connected with the absorption liquid filter through circulating pump by pipeline, and the outlet of absorption liquid filter is connected with spray thrower by pipeline.
Improve, its distributed architecture of described spray thrower is the structure that forms spiral distribution from top to bottom in the helical form annular chamber again.
Above-mentioned gas-liquid distributor may be selected to be 1 to 6, is distributed in the inner chamber on absorption tower with compartment of terrain up and down respectively.
As further improvement, be provided with the ammonia retracting device at described absorption tower inner chamber and between the clean gas floss hole at top gas-liquid distributor and top, absorption tower, this ammonia retracting device is connected with absorption liquid in the concentrated zoneofoxidation through circulating pump by pipeline; And be provided with wire mesh demister in the absorption tower inner chamber between ammonia retracting device and clean gas floss hole, and be provided with below the wire mesh demister dash to drench be entrained in drop on the wire mesh demister dash the pouring device, should dash and drench device and be connected with drilling fluid through circulating pump one by pipeline.
Above-mentioned concentrated zoneofoxidation by pipeline with the structure optimization that the extraneous air hose that is provided with air-blaster is connected is: 1 to 6 gas distributor that stretches into by pipeline in concentrating zoneofoxidation and being arranged at concentrated zoneofoxidation through air blast is connected.
Improve, described waste gas inlet port place also can be provided with chilling spray device one again, and this chilling spray device one is connected with cooling fluid by pipeline.
Improve, described chilling spray device one has two again, and chilling spray device one is connected with drilling fluid in the circulating pump one by pipeline, and another chilling spray device one is connected with absorption liquid in the concentrated zoneofoxidation through circulating pump by pipeline.
The shape of its peripheral shape of above-mentioned gas-liquid distributor and absorption tower cross-sectional perimeter is suitable and be packaged in the inner chamber on absorption tower.
Compared with prior art, the invention has the advantages that: waste gas cooling is to carry out in the cooling device in the absorption tower, enter then through concentrating zoneofoxidation, gas has been reduced to 45~60 ℃ in the temperature that enters the absorption tower inner chamber, because temperature is low more, gas-liquid contact back assimilation effect is just good more, so absorptivity increases considerably after the gas of low temperature enters the absorption tower; And cooling device of the present invention can not dilute absorption liquid, obtains the absorption tower of same assimilation effect and need not strengthen the height of desulfurizing tower (being the absorption tower) or increase liquid-gas ratio, thereby can reduce the expense that is equipped with investment and operation effectively.Also have, the shape of the peripheral shape of gas-liquid distributor of the present invention and absorption tower cross-sectional perimeter is suitable, and is packaged in the inner chamber on absorption tower, has eliminated the bias current phenomenon of gas-liquid, this structure has promoted the contact area of gas-liquid, thereby further improves assimilation effect; The present invention is applicable to SO in all sulphur-containing exhaust gas
2Remove, and convert it into ammonium sulfate fertilizer, dust removal efficiency and desulfurization degree are higher simultaneously, meet the national environmental protection emission request, and producing ammonium sulfate byproduct chemical fertilizer, can win benefit for enterprise, and desulfurizing tower (promptly refers to the absorption tower, the desulfurizing tower of the following stated all refers to the absorption tower) can simplify flow process, reduce equipment investment, save the area, and waste gas dedusting, cooling, the processes such as absorption liquid, desulfurization, oxidation that concentrate are concentrated on and finish in the desulfurizing tower, improvement gas flow process makes full use of the device space, and operating condition elasticity is big.
Description of drawings
Fig. 1 is the structural representation of the embodiment of the invention;
Fig. 2 is the structural representation that is provided with dedusting mechanism among Fig. 1 in cooling device;
Fig. 3 is the upward view of gas-liquid distributor among Fig. 1;
Fig. 4 is the vertical view of gas-liquid distributor among Fig. 1;
Fig. 5 is the vertical view of Fig. 1 cooling body.
The specific embodiment
Embodiment describes in further detail the present invention below in conjunction with accompanying drawing.
Embodiment one, extremely shown in Figure 5 as Fig. 1, Fig. 3, the device that removes sulfur dioxide in the waste gas in the present embodiment, include absorption tower 1, the side, middle part on absorption tower 1 is provided with waste gas inlet port 12, in absorption tower 1, be provided with gas- liquid distributor 3,1 top is provided with clean gas floss hole 11 on the absorption tower, 1 bottom is provided with the concentrated zoneofoxidation 13 of absorption liquid and on the absorption tower, concentrate zoneofoxidation 13 and be connected with the extraneous air hose that is provided with air-blaster 5, make airborne energy of oxidation oxidation ammonium sulfite or ammonium bisulfite by pipeline.Gas-liquid distributor 3 is connected through the absorption liquid of circulating pump 31 with concentrated zoneofoxidation 13 by pipeline.Cooling device in described waste gas inlet port 12 and the absorption tower 1 is connected, the gas vent of this cooling device is connected with concentrated zoneofoxidation, concentrate zoneofoxidation 13 and absorption tower 1 intracavity inter-connection, and concentrated zoneofoxidation 13 flows to collection place of ammonium sulfate finished product by the pipeline that is provided with valve through extraction pump 6.The structure of described cooling device is: be provided with cooling cylindrical shell 4 in absorption tower 1, it in the cooling cylindrical shell 4 the helical form annular chamber 41 of coiling downwards, described waste gas leads to annular chamber 41 from waste gas inlet port 12, the gas outlet of annular chamber 41 is connected with concentrated zoneofoxidation 13, be provided with spray thrower 42 in annular chamber 41, spray thrower 42 is connected with absorption liquid or cooling fluid by the circulating pump of pipeline 1 outside through the absorption tower.Described spray thrower 42 is the structure that forms spiral distribution from top to bottom in helical form annular chamber 41.Above-mentioned gas-liquid distributor 3 may be selected to be 1 to 6, is distributed in the inner chamber 14 on absorption tower 1 with compartment of terrain up and down respectively.Certainly number also can be than 6 more, specifically can decide by designing requirement.Be provided with ammonia retracting device 23 at absorption tower 1 inner chamber and between the clean gas floss hole 11 at top gas- liquid distributor 3 and 1 top, absorption tower, this ammonia retracting device 23 is connected with absorption liquid in the concentrated zoneofoxidation 13 through circulating pump 31 by pipeline.And be provided with wire mesh demister 2 in absorption tower 1 inner chamber between ammonia retracting device 23 and clean gas floss hole, and be entrained on the wire mesh demister 2 dashing of drop and drench device 21 being provided with below the wire mesh demister 2 dash to drench, should dash and drench device 21 and be connected with drilling fluid through circulating pump 1 by pipeline.And concentrate zoneofoxidation 13 by pipeline with the structure that the extraneous air hose that is provided with air-blaster 5 is connected be: 1 to 6 gas distributor 51 that stretches into by pipeline in concentrating zoneofoxidation 13 and being arranged at concentrated zoneofoxidation 13 through air blast 5 is connected.12 places also are provided with chilling spray device 1 at the waste gas inlet port, and this chilling spray device 1 is connected with cooling fluid by pipeline.This chilling spray device 1 has two, and chilling spray device 1 is connected with drilling fluid in the circulating pump 1 by pipeline, and another chilling spray device 1 is connected with absorption liquid in the concentrated zoneofoxidation 13 through cooling circulating pump 131 by pipeline.The shape of the shape of the periphery of above-mentioned gas-liquid distributor 3 and absorption tower 1 cross-sectional perimeter is suitable and be packaged in the inner chamber 14 on absorption tower 1.
Embodiment two, as shown in Figure 2, present embodiment is identical with the basic structure of embodiment one, different is, in annular chamber 41, be provided with dedusting mechanism, the structure of this dedusting mechanism is: the toroidal frame 7 that is provided with vertical setting in annular chamber 41, be provided with at the top of toroidal frame 7 and prevent that liquid from entering the liquid barrier 71 of toroidal frame inner chamber 70, have in the side that is positioned at toroidal frame 7 and can make waste gas enter the air admission hole 72 of toroidal frame inner chamber 70, toroidal frame inner chamber 70 is connected with concentrated zoneofoxidation 13, in annular chamber 41, be provided with and prevent that absorption liquid from entering the clamping plate 43 that concentrate zoneofoxidation 13, absorption liquid in the described annular chamber 41 is connected with absorption liquid filter 8 through circulating pump 81 by pipeline, and the outlet of absorption liquid filter 8 is connected with spray thrower 42 by pipeline.
Below the invention will be further described.
The mechanism of exhuast gas desulfurization is alkaline absorbent and SO
2Gas generation chemical reaction according to the kind of absorbent, mainly is divided into desulfurization of calcium method and the ammonia process of desulfurization two classes.The desulfurization of calcium method can obtain by-produced gypsum in theory, but China's gypsum resource is abundant, and in fact gypsum by-product is all as waste dump, both land occupations, and contaminated environment has consumed limestone resource again, therefore has the people that the desulfurization of calcium method is called the method for abandoning.The byproduct of the ammonia process of desulfurization is an ammonium sulfate fertilizer, neither influences the total amount of nitrogenous fertilizer, has adjusted the fertilizer structure of China again.Therefore, the desulfurization of calcium method will be replaced by the ammonia process of desulfurization gradually.
In the ammonia process of desulfurization, generally include following chemical reaction:
(1) SO in the absorption waste gas
2
Effective absorbent components in the absorption liquid is an ammonium sulfite, recovers the absorbability of absorption liquid by replenishing ammoniacal liquor, and the ratio of ammonium sulfite and ammonium bisulfite is the addition by adjustment ammoniacal liquor in absorption liquid, controls promptly that the pH value realizes.Ammonium sulfite also can directly be made fertilizer and sell, but because its unstable chemcial property generally need be oxidized to ammonium sulfate with it, is reprocessed into solid, is convenient to store and transportation.
(2) oxidation of ammonium sulfite
In ammonium sulfite solution, directly rouse air, just can obtain oxidation product ammonium sulfate:
Conventional art is that dust arrester is set before desulfurizing tower, the waste gas after the flue dust dedusting in the waste gas is entered desulfurizing tower remove SO
2The partial monopoly technology handles ammonium sulfite warp workshop section later as byproduct, and the patented technology that has is provided with oxidation panel outside Ta Nei or tower, be ammonium sulfate with sulfite oxidation, and ammonium sulfate is as byproduct.The present invention realizes waste gas dedusting, cooling, the processes such as absorption liquid, desulfurization, oxidation that concentrate are concentrated in a desulfurizing tower and realized, and producing ammonium sulfate byproduct.
Waste gas of the present invention is meant the tail gas of industrial discharges such as refining miner industry, sulfuric acid industry, coal and oil boiler or is called waste gas; Described device is a kind of novel desulfurizing tower (promptly refer to the absorption tower, the desulfurizing tower of the following stated all refers to the absorption tower), realizes dedusting simultaneously in tower, lowers the temperature, proposes dense, desulfurization, oxidizing process.Concrete steps are as follows: waste gas enters the dedusting section and removes flue dust; Enter temperature descending section through gas down-comer (promptly referring to annular chamber 41), be absorbed liquid cooling but, simultaneously absorption liquid be evaporated carry dense; Waste gas enters absorber portion in the absorption tower, with the absorption liquid counter current contacting; Remove SO
2Waste gas after the cat head wire mesh demister reclaims drop, go to chimney or back workshop section.Described dedusting section (promptly referring to dedusting mechanism) is an annular chuck of desulfurizing tower, shower nozzle is set to gas humidification at inlet tube, and waste gas tangentially enters, and wetted soot dust granule is reunited and grown up, and rushes at the tower wall with air-flow and obtains separating.Described dedusting section also has the effect of preliminary cooling exhaust, by regulating injection flow rate control EGT.At temperature descending section, absorption liquid is by waste gas cooling liberated heat evaporation and concentrating.Described absorber portion is the absorption tower that is provided with some liquid distribution troughs, and segmentation sprays into absorption liquid in tower, has cancelled filler in the tower, and vapour lock is descended, and can not produce stifled tower phenomenon simultaneously.The place is provided with wire mesh demister at waste gas outlet, in order to catch the gas entrained drip, an absorption liquid spray pipe (promptly referring to dash pouring device 21) is set below wire mesh demister, reduces the ammonia loss.Air adds with the form of bubbling in oxidation panel (promptly referring to concentrate zoneofoxidation) bottom, enters the absorption tower inner chamber with the waste gas merging after the oxidation, discharges from cat head.
As shown in Figure 2, contain SO
2Industrial waste gas enter desulfurizing tower dedusting section from inlet, guide plate pilot gas and cleaning solution descend in dedusting section rotation.After the dedusting, gas enters temperature descending section by down-comer, is absorbed liquid cooling but, absorption liquid be evaporated carry dense.The waste gas that is cooled to 45~60 ℃ contacts SO by entering communicating pipe in the absorption tower with the absorption liquid of gas-liquid distributor is reverse
2, SO
3And sour gas such as NOx is absorbed.Liquid distribution trough is set in the absorption tower, and the absorption liquid of spray through repeatedly distributing, is optimized the gas-liquid contact conditions again in tower, improve absorption efficiency.Remove SO
2After the silk screen demister reclaims droplets entrained, go to chimney or back workshop section Deng the waste gas of sour gas.At the waste gas outlet place ammonia retracting device is set also at this device, is used for absorbing the gas ammonia that to carry secretly in the waste gas, reduce the ammonia loss, can regulate flow according to the gas componant result of laboratory test of waste gas.Air blast blasts the gas distributor that concentrates in the zoneofoxidation with air, and air merges at temperature descending section by floss hole and industrial waste gas at last, and label 15 wherein refers to liquid level gauge, and label 16 refers to pH meter.
As shown in Figure 1, SO
2The industrial waste gas input port enter cooling device in the desulfurizing tower, guide plate 44 guiding gases and absorption liquid in cooling device rotate decline in annular chamber.Herein, absorption liquid contacts with the gas following current, and gas is cooled to 45~60 ℃, and absorption liquid is concentrated.Guiding function through guide plate is mixed gas and liquid step by step, and actual contact route lengthening prevents short circuit phenomenon, has improved efficient.
After the dedusting, gas entered in the absorption tower by communicating pipe 17, contacted SO with absorption liquid is reverse
2, SO
3And sour gas such as NOx is absorbed.Gas-liquid distributor is set in the absorption tower, the absorption liquid of spray is distributed in tower again, optimize the gas-liquid contact conditions, improve absorption efficiency.Remove SO
2After, waste gas directly discharges or goes back workshop section.Be provided with water flushing device (promptly referring to dash pouring device 21) and ammonia retracting device 23 in floss hole (promptly referring to clean gas floss hole 11) below respectively, be used for reclaiming absorption drop and the ammonia carried secretly in the waste gas, reduce the ammonia loss.Absorption liquid flows to the concentrate oxygen district under the liquid column inner chamber, air blast 5 blasts air the gas distributor that concentrates in the zoneofoxidation.The absorption liquid that concentrates in the zoneofoxidation flows into the temperature descending section bottom by overflow pipe 45.Absorbent recirculation pump 31 is squeezed into the absorption liquid circulation in the absorption tower, and cooling circulating pump 131 is squeezed into temperature descending section with the absorption liquid circulation, and absorption liquid is concentrated gradually.When ammonium sulfate in the absorption liquid reaches more than the 45wt%, utilize extraction pump 6 to be sent to ammonium sulphate crystallizer and carrying.Through after workshop section handle and to obtain product ammonium sulfate.Mend ammoniacal liquor and enter absorption liquid through aqua ammonia pump 9 or ammonia valve 91, regulate the pH value, the pH meter indication is to recover its absorption.Absorption liquid liquid level in the liquid level gauge indication desulfurizing tower prevents to find time.
This paper vapour-liquid distributor comprises absorption tray, is distributed with bubbling head or bubble-cap on tower tray, is provided with spray head above tower tray.The absorption tray top spray head double as of top gas-liquid distributor is the ammonia retracting device.