CN103301719A - System and method for removing sulfur dioxide from exhaust gas - Google Patents
System and method for removing sulfur dioxide from exhaust gas Download PDFInfo
- Publication number
- CN103301719A CN103301719A CN2013102690204A CN201310269020A CN103301719A CN 103301719 A CN103301719 A CN 103301719A CN 2013102690204 A CN2013102690204 A CN 2013102690204A CN 201310269020 A CN201310269020 A CN 201310269020A CN 103301719 A CN103301719 A CN 103301719A
- Authority
- CN
- China
- Prior art keywords
- gypsum
- absorption liquid
- absorption
- unit
- waste gas
- 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.)
- Pending
Links
Images
Abstract
The invention provides a system and a method for removing sulfur dioxide from exhaust gas. The system comprises an exhaust gas absorption unit, an absorption liquid oxidizing regeneration unit, an absorption liquid filtering and separating unit, a gypsum crystallizing unit and a gypsum dehydrating unit. The system and the method for removing sulfur dioxide from exhaust gas provided by the invention are capable of efficiently removing sulfur dioxide in the exhaust gas so that the exhaust gas is up to the latest emission standard; besides, the utilization rate of limestone is increased, and the generated gypsum is low in content of impurities such as calcium sulfite, dust and the like, and high in purity; as a result, the desulfurized gypsum can be utilized sufficiently.
Description
Technical field
The present invention relates to treatment system and the method for waste gas, be specially a kind of system and method that from waste gas, removes sulfur dioxide.
Background technology
In the combustion process of the sulfur-containing compounds such as coal fired power generation, steel sintering, oil, natural gas, can discharge a large amount of sulfur dioxide.Sulfur dioxide is a kind of gas that is heavier than air, has off-odor, is sulfuric acid by eremacausis in malaria and forms acid rain.China's sulfur dioxide annual emissions occupies first place in the world.Mainly reach 30% of area by the sulfate type acid rain contamination hazard area due to the sulfur dioxide (SO2) emissions, people's healthy and ecological environment has been caused extremely serious harm.In recent years, for the discharge capacity of protection of the environment, minimizing sulfur dioxide, domestic a large amount of coal fired power generation unit has been installed flue gas desulfur device, and the flue gas removal sulfur dioxide of the industries such as nonferrous smelting, iron and steel, petrochemical industry is also day by day universal, and discharge standard is more and more stricter.
At present, the flue gas desulfurization technique technology of having used in thermal power plant has: the kinds more than ten such as lime stone (lime)-gypsum wet, flue gas circulating fluidized bed method, sea water desulfuration method, rotary spraying and drying method, in-furnace calcium spraying tail flue gas humidification activation method, active coke absorption method, the ammonia process of desulfurization, the desulfur technology of domestic thermal power plant practicality mainly contains three kinds, Wet Limestone (lime)-gypsum (wet method), spray dry desulfurization method (semidry method), recirculating fluidized bed method (dry method).The internal and overseas situation is the same, and wet desulfurization of flue gas by limestone-gypsum method is still the main flow technology.According to statistics, by the end of the year 2008, put into operation, in the flue gas desulphurization technology of building and having signed a contract, Gypsum Wet accounts for more than 90%.
Lime stone (lime)-gypsum wet flue gas desulfurizing technique mainly is to adopt lime stone cheap and easy to get or lime as desulfurization absorbent.When adopting lime stone as absorbent, lime stone is made the absorption slurries through the pulverizing and jevigating powdering with the water mix and blend.When adopting lime as absorbent, pulverized limestone adds the water stirring and makes the absorption slurries after digestion process.In the absorption tower, absorb slurries and contact mixing with flue gas, the sulfur dioxide in the flue gas and the calcium carbonate in the slurries carry out chemical reaction and are absorbed and remove, and react with the oxidation air that blasts, and end product is gypsum.Flue gas after the desulfurization is removed droplet through demister successively, and behind the heater heat temperature raising, through smoke stack emission, the gypsum that desulfurization forms can fully utilize by booster fan.The reaction mechanism of this technique is:
(1) absorbent is lime
Absorb: SO
2(g) → SO
2(l)+H
2O
SO
2(l)+H
2O→H
++HSO
3 -
HSO
3 -→H
++SO
3 2-
Dissolving: Ca (OH)
2(s) → Ca
2++ 2OH
-
CaSO
3(s)→Ca
2++SO
3 2-
Neutralization: OH
-+ H
+→ H
2O
OH
-+HSO
3 -→SO
3 2-+H
2O
Oxidation: HSO
3 -+ 1/2O
2→ SO
4 2-+ H
+
SO
3 2-+1/2O
2→SO
4 2-
Crystallization: Ca
2++ SO
3 2-+ 1/2H
2O → CaSO
31/2H
2O (s)
Ca
2++SO
4 2-+2H
2O→CaSO
4·2H
2O(s)
(2) absorbent is lime stone
Absorb: SO
2(g) → SO
2(l)+H
2O
SO
2(l)+H
2O→H
++HSO
3 -
HSO
3 -→H
++SO
3 2-
Dissolving: CaCO
3(s)+H
+→ Ca
2++ HCO
3 -
Neutralization: HCO
3 -+ H
+→ CO
2(g)+H
2O
Oxidation: HSO
3 -+ 1/2O
2→ SO
4 2-+ H
+
SO
3 2-+1/2O
2→SO
4 2-
Crystallization: Ca
2++ SO
3 2-+ 1/2H
2O → CaSO
31/2H
2O (s)
Ca
2++SO
4 2-+2H
2O→CaSO
4·2H
2O(s)
In lime stone (lime)-gypsum wet flue gas desulfurizing technique, the absorption of the dissolving of lime stone, the oxidation of calcium sulfite and sulfur dioxide is the process of a contradiction.High pH value is conducive to the absorption of sulfur dioxide, pH is 6 o'clock, the sulfur dioxide assimilation effect is best, but this moment, the dissolving of lime stone and the oxidation of calcium sulfite are subject to severe inhibition, the utilization rate of lime stone descends, operating cost improves, and fouling, clogging easily occur, and occurs being difficult in a large number the calcium sulfite that dewaters in the product, and it is defective to cause gypsum qualitt owing to residue calcium carbonate content in the gypsum is high, and the gypsum comprehensive utilization is difficult to realize.Low pH value is conducive to the oxidation of calcium sulfite, lime stone solubility improves, when blasting air by a certain percentage, calcium sulfite almost can all obtain oxidation, and the quality of gypsum is guaranteed, but low pH value is suppressed the absorption of sulfur dioxide, desulfuration efficiency reduces greatly, and when the pH value was 4, the absorption of sulfur dioxide almost can't be carried out, and it is acid that absorption liquid is, and equipment is also had corrosion.Therefore, keeping the suitable pH value of desulfurizing tower is an important means that guarantees desulfuration efficiency, improves gypsum qualitt.It is proper that the pH value of common desulfurizing tower remains on 5.2-5.5, and the desulfuration efficiency of limestone-gypsum method can reach 95%.
Require SO in existing national fossil-fuel power plant atmospheric pollutant emission standard and the emission standard of air pollutants for boilers
2Less than 100mg/m
3If the content of sulfur dioxide in flue gas is slightly high, lime stone (lime)-gypsum wet flue gas desulfurizing technique just can not meet the demands, and the large quantities of lime stone (lime) that is moving at present-gypsum method flue gas desulfurization device all renovates needs, to improve desulfuration efficiency.
Contain excessive calcium carbonate and calcium sulfite in the gypsum of existing lime stone (lime)-gypsum wet flue gas desulfurizing technique by-product, in addition, in a lot of power plant, because the impact of the efficiency of dust collection of electric precipitation, dust content is higher in the flue gas, and dust constantly adds in the limestone desulfurizer and circulates, and desulfuration efficiency is reduced, and affect gypsum crystallization and quality, be unfavorable for the comprehensive utilization of gypsum.The utilization rate of the thermoelectricity desulfurated plaster that China is present is about 10%, and most desulfurated plasters are in the state that nature is stored up, and secondary pollution occurs owing to the weathering of desulfurated plaster causes again discharging sulfur dioxide.
Summary of the invention
In order to solve the problems referred to above that exist in existing lime stone (lime)-gypsum wet flue gas desulfurizing technique, the invention provides a kind of system and method that from waste gas, removes sulfur dioxide.
A kind of system that removes sulfur dioxide from waste gas comprises the waste gas absorption unit, absorption liquid oxidation regeneration unit, absorption liquid filtration and separative element, gypsum crystallization unit and the gypsum dehydration unit that connect successively.
Described system also comprises the absorption liquid supplementary units, and described absorption liquid supplementary units is connected with gypsum dehydration unit, waste gas absorption unit.
Described waste gas absorption unit comprises the absorption tower, is provided with air inlet in the absorption tower, is used for one or more layers distributor, demister and the gas outlet of spray-absorption liquid.
Described absorption liquid oxidation regeneration unit comprises oxidation air blower fan, absorption liquid storage tank, circulated sprinkling pump, the flow regulator that connects successively, wherein, the absorption liquid storage tank is positioned at the bottom on absorption tower and is connected with the absorption tower, bottom at the absorption liquid storage tank is provided with air sparger, and flow regulator also is connected with the top on absorption tower.
Described absorption liquid filters and separative element comprises absorption liquid filter pump, filter, knockout drum and compressed air system.
Described gypsum dehydration unit comprises gypsum excavationg pump, gypsum thickener, gypsum filter and gypsum washing system, and wherein, described gypsum filter links to each other with the absorption liquid storage tank respectively with knockout drum.
Described absorption liquid supplementary units comprises that the Separation of gypsum water storage tank, Separation of Water delivery pump, the absorption liquid that connect successively replenish tank and absorption liquid make-up pump.
A kind of method of using said system to remove sulfur dioxide from waste gas comprises the steps:
The waste gas that a) will contain sulfur dioxide passes into the waste gas absorption unit, and waste gas is discharged from the waste gas absorption unit after contacting with absorption liquid and removing sulfur dioxide;
B) absorption liquid of step in a) is with after waste gas contacts sulfur dioxide absorption, enter absorption liquid oxidation regeneration unit, sulfur dioxide is oxidized to sulfur trioxide, and sulfur trioxide and water reaction generate sulfuric acid, absorption liquid is regenerated, and the partial regeneration absorption liquid is sent back to the waste gas absorption unit;
C) with step b) in remaining regeneration absorption liquid pass into that absorption liquid filters and separative element filters, the filtrate layering forms water and organic phase, separatory;
D) with step c) in water pass into the gypsum crystallization unit, described water mixes in the gypsum crystallization unit with the lime stone that comes from the lime white supply system or lime slurry, generates the gypsum thin pulp;
E) with steps d) described gypsum thin pulp is delivered to the gypsum dehydration unit and dewaters, and obtains gypsum and Separation of gypsum water.
Described method also comprises step c) organic phase and step e) Separation of gypsum water be delivered to respectively absorption liquid oxidation regeneration unit, both are sent to the waste gas absorption unit and reuse after absorption liquid oxidation regeneration unit mixes.
Described steps d) calcium ion that lime stone or lime slurry provide in the gypsum crystallization unit and the mol ratio of aqueous phase sulfate ion greater than 0.5 less than 1.
Described absorption liquid is the mixed liquor of sulfoxide type organic absorbent and water.
Described sulfoxide type organic absorbent is petrolenum sulfoxide.
The system and method that from waste gas, removes sulfur dioxide provided by the present invention, can remove efficiently the sulfur dioxide in the waste gas, make it satisfy up-to-date discharge standard, and improve the utilization rate of lime stone, the impurity contents such as calcium carbonate, calcium sulfite and dust are few in the gypsum that produces, purity is high, thereby desulfurated plaster is fully used.And can transform at existing lime stone (lime)-gypsum wet desulfurizer, reduce investment outlay and the transformation time.
Description of drawings
Fig. 1 is the present invention removes the system of sulfur dioxide from waste gas structural representation.
Wherein, description of reference numerals is as follows:
11, absorption tower 12, air inlet 13, distributor
14, demister 15, gas outlet 21, oxidation air blower fan
22, absorption liquid storage tank 23, air sparger 24, circulated sprinkling pump
25, I flow regulator 31, absorption liquid filter pump 32, filter
33, knockout drum 41, crystallization tank 51, gypsum excavationg pump
52, gypsum thickener 53, gypsum filter 54, gypsum washing system
61, Separation of gypsum water storage tank 62, Separation of Water delivery pump 63, absorption liquid replenish tank
64, absorption liquid make-up pump 65, II flow regulator
The specific embodiment
Below, the system and method that in conjunction with the drawings and the specific embodiments the present invention is removed sulfur dioxide from waste gas is described in detail.
Embodiment 1
As shown in Figure 1, a kind of system that removes sulfur dioxide from waste gas comprises waste gas absorption unit, absorption liquid oxidation regeneration unit, absorption liquid filtration and the separative element, gypsum crystallization unit, the gypsum dehydration unit that connect successively, and the absorption liquid supplementary units.
The waste gas absorption unit comprises absorption tower 11, the sidewall of 11 interior bottoms is provided with air inlet 12 on the absorption tower, 11 upper space is provided with three layers of distributor 13 on the absorption tower, distributor 13 can also be one or more layers, demister 14 is positioned at the top of distributor 13, and the sidewall of 11 cats head is provided with gas outlet 15 on the absorption tower.
Comprise finite concentration sulfur dioxide, NO
2With nitrogen oxide such as NO, and the waste gas of dust 11 bottom air inlet 12 enters absorption tower 11 from the absorption tower, waste gas is 11 interior risings on the absorption tower, with the absorption liquid counter current contacting that sprays from distributor 13, absorption liquid is the mixed liquor of sulfoxide type organic absorbent and water, the sulfoxide type organic absorbent contains the S=O group, the S=O base is polar group, negative pole is positioned on the oxygen, and oxygen atom around without steric restriction, positively charged sulphur atom generation dipole-dipole interaction easily and in the sulfur dioxide molecule, and the oxygen atom in the sulfur dioxide molecule also with the S=O base in positively charged sulphur atom have an effect, thereby form stable compound, therefore, the sulfoxide type organic absorbent has good absorbability to sulfur dioxide, and by the counter current contacting of absorption liquid and charging waste gas, the sulfur dioxide in the waste gas is absorbed, simultaneously, the nitrogen dioxide in the waste gas and a part of dust have also entered absorption liquid.The waste gas that has removed sulfur dioxide is discharged absorption towers 11 by gas outlet 15 after removing water droplet through demister 14, continues discharging after heat exchange heats up.In order to prevent that demister 14 from stopping up, and carries out periodic cleaning with proper amount of fresh water to it.
Absorption liquid oxidation regeneration unit comprises oxidation air blower fan 21, absorption liquid storage tank 22, circulated sprinkling pump 24, the I flow regulator 25 that connects successively, wherein, absorption liquid storage tank 22 is positioned at the bottom on absorption tower 11 and is connected with absorption tower 11, be provided with air sparger 23 in the bottom of absorption liquid storage tank 22, I flow regulator 25 also is connected with the top on absorption tower 11.
11 top sprays are drenched the absorption liquid storage tank 22 that the absorption liquid that gets off flows under the influence of gravity into 11 bottoms, absorption tower from the absorption tower, absorption liquid storage tank 22 is used for collecting and storing the absorption liquid that 11 overhead stream are got off from the absorption tower, the air that oxidation air blower fan 21 provides is evenly distributed on the bottom of absorption liquid storage tank 22 by air sparger 23, airborne oxygen becomes sulfur trioxide with the oxidizing sulfur dioxide that absorbs on the organic absorbent in the absorption liquid, sulfur trioxide and water reaction generate sulfuric acid, thereby absorbent is regenerated, the ability that possesses again sulfur dioxide absorption, after absorbent after the regeneration is recycled spray pump 24 extractions, reenter absorption tower 11, continue to recycle.As required, the part of absorption liquid can be delivered to the superiors' nozzle of distributor 13, its flow is regulated by I flow regulator 25, and I flow regulator 25 is control valve in the present embodiment.
In the absorption process of sulfoxide type organic solvent to sulfur dioxide, do not form firmly chemical bond between sulfoxide type organic solvent and sulfur dioxide molecule, therefore, be easy to desorb and regeneration.
Usually oxidizing sulfur dioxide becomes sulfur trioxide to need the existence of catalyst, and what play catalyst action in this oxidizing process of the present invention is nitrogen dioxide, and its reaction is expressed as follows:
SO
2+NO
2+H
2O=H
2SO
4+NO
NO+1/2O
2=NO
2
Alternating oxidation effect by nitrogen oxide makes oxidizing sulfur dioxide become sulfur trioxide with reduction, is absorbed by water at last.Nitrogen oxide type gas constantly is given to sulfur dioxide with airborne oxygen during the course, and then is transformed into sulfuric acid.
Absorption liquid filters and separative element comprises absorption liquid filter pump 31, filter 32, knockout drum 33 and compressed air system, and knockout drum 33 also replenishes tank 63 with following crystallizing tank 41, absorption liquid respectively and is connected.
Along with the carrying out of waste gas absorption and absorption liquid oxidation regeneration, SO in the absorption liquid
4 2-Concentration more and more higher, the Dust Capacity that enters in the absorption liquid is also more and more, in order to keep absorption liquid suitable pH value and suspension content, a part of absorption liquid is transported to absorption liquid filtration and separative element; Absorption liquid filter pump 31 is extracted absorption liquid to be filtered out from absorption liquid storage tank 22, be transported to filter 32, filter 32 separates suspension wherein with other component, obtain filter cake and filtrate, filter cake is discharged native system and is disposed separately outward, filtrate enters knockout drum 33, because the suspension in the absorption liquid is deviate from, therefore, the mixed liquor of sulfoxide type organic absorbent and water will be put rapidly the lower floor's water that is separated into the upper organic phase that is rich in organic absorbent and is rich in sulfate radical under Action of Gravity Field, organic phase enters the absorption liquid supplementary units, and water enters the gypsum crystallization unit.
Because the dust granules in the flue gas is tiny, organic absorbent can adhere to and is wrapped in the particle skin, and, because the powder emulsifying effect of subparticle, can form the emulsified state of organic absorbent and water, for this reason, the interruption mode of operation of " filtering-purge " is adopted in the filtration of filter 32, after each filter cycle, purge filter cake with compressed air, compressed air provides higher purging pressure, reducing organic absorbent carrying secretly and adhere on filter cake, thereby reduces the loss of absorbent.The flow of absorption liquid to be filtered is determined according to the pH value of absorption liquid.
The gypsum crystallization unit comprises crystallization tank 41, lime white supply system (not shown).After aforementioned water enters crystallization tank 41, under agitation mix with the lime stone that comes from the lime white supply system or lime slurry, the sulfate radical generation chemical reaction of the calcium carbonate in the lime white (or calcium hydroxide) and aqueous phase, generate calcium sulfate, namely form the gypsum thin pulp after reaching certain saturation degree.Reaction equation is expressed as follows:
Adopt lime stone: CaCO
3+ SO
4 2-+ 2H
++ H
2O → CaSO
42H
2O (s)+CO
2Or
Adopt lime: Ca (OH)
2+ SO
4 2-+ 2H
+→ CaSO
42H
2O (s)
In above-mentioned gypsum crystallization process, unlike conventional lime stone (lime)-gypsum, need the dosage of calcium carbonate (or calcium hydroxide) excessive, but require calcium carbonate (or calcium hydroxide) relative deficiency, control by the pH value, make all dissolvings of calcium carbonate (or calcium hydroxide), do like this is in order to reach two purposes, the one, prevent that excessive undissolved calcium carbonate from entering the quality that gypsum affects gypsum, the 2nd, after returning absorption system, the calcium carbonate that prevents excessive dissolving in absorption system, generates calcium sulfate, and cause the calcium sulfate supersaturation and separate out, and and then cause stopping up and wearing and tearing.Because calcium carbonate (or calcium hydroxide) is dissolving all, therefore, limestone particle can be larger, and needn't be as conventional lime stone (lime)-gypsum in order to pursue quickly absorption rate, higher lime stone utilization rate and require thinner limestone particle, therefore, the present invention requires and can relax for the particle diameter of lime stone, can save the energy consumption of grinding stone lime stone.
The gypsum dehydration unit comprises gypsum excavationg pump 51, gypsum thickener 52, gypsum filter 53 and gypsum washing system 54; The gypsum thin pulp that forms in the gypsum crystallization unit enters the gypsum dehydration unit, the gypsum thin pulp is extracted out by gypsum excavationg pump 51, deliver to gypsum thickener 52, with gypsum thin pulp concentrate to moisture content approximately about 40%, calcium plaster after the concentrate enters gypsum filter 53 and further dewaters, the backwater of gypsum thickener 52 turns back to crystallization tank 41, gypsum filter 53 further is dewatered to moisture content approximately 10% with calcium plaster, in dehydration, with the fresh water (FW) washing gypsum that comes from gypsum washing system 54, remove HCl, FeCl in the gypsum
2, the soluble impurity such as silicate, finally form finished product gypsum and Separation of gypsum water.
The absorption liquid supplementary units comprises that the Separation of gypsum water storage tank 61, Separation of Water delivery pump 62, the absorption liquid that connect successively replenish tank 63 and absorption liquid make-up pump 64, and wherein, absorption liquid make-up pump 64 also links to each other with absorption tower 11.Separation of gypsum water enters the absorption liquid supplementary units, Separation of gypsum water storage tank 61 is used for storing Separation of gypsum water, Separation of Water delivery pump 62 is with Separation of gypsum water extraction liter, wherein a part of Separation of Water is delivered to absorption liquid and is replenished tank 63, another part Separation of Water is discharged native system, to prevent that Cl-is in intrasystem accumulation; The flow of Separation of Water is regulated by II flow regulator 65, and II flow regulator 65 is control valve in the present embodiment.Absorption liquid replenishes tank 63 and is used for receiving the organic phase that comes from absorption liquid filtration and separative element, the Separation of Water that comes from Separation of Water delivery pump 62, and the fresh water that replenishes, absorption liquid replenishes the tank 63 interior agitators that arrange, and makes water and organic absorbent form the emulsus mixed liquor by stirring.Absorption liquid make-up pump 64 is transported to the waste gas absorption unit with the emulsus mixed liquor.Because the pH value of emulsus mixed liquor is higher, therefore, that its front end of directly delivering to distributor 13 the superiors' nozzles is more favourable to dissolving and the absorption of sulfur dioxide in absorption liquid.
Calcium sulfate is undersaturated in the emulsus mixed liquor, there is not the existence of calcium carbonate (or calcium hydroxide) yet, therefore, in waste gas absorption, absorption liquid oxidation regeneration, absorption liquid filtration and separation process, calcium sulfate in the solution all is in undersaturated condition, do not have crystallization in the solution, avoided ubiquitous fouling in conventional lime stone (lime)-gypsum, obstruction and wear phenomenon.
The said equipment is not particularly limited, and can adopt same category of device well known in the art.Empty spray tower can be adopted in absorption tower 11, also can adopt packed tower, and absorption liquid storage tank 22 can manufacture one with absorption tower 11, also can separately build, and this is not particularly limited.
Certainly, above-described embodiment only is used for exemplary illustration, can be out of shape said apparatus, for example, can omit the absorption liquid supplementary units, organic phase and Separation of gypsum water directly are supplied to absorption liquid storage tank 22 carry out recyclingly, can effectively remove equally the sulfur dioxide in the waste gas.
The system and method that from waste gas, removes sulfur dioxide of the present invention, owing to adopt the mixture that sulfur dioxide is had the sulfoxide type organic absorbent of good absorption and desorption performance and water as absorption liquid, higher to the removal efficiency of sulfur dioxide.Before forming the solid gypsum, the suspension that is formed by dust in the waste gas is filtered out in advance, can not enter in the gypsum, can not form calcium sulfite in the system yet, in the gypsum crystallization unit dosage of calcium carbonate do not need excessive, calcium carbonate (or calcium hydroxide) in the lime stone (lime) has all dissolved, there is not undissolved calcium carbonate (or calcium hydroxide) to enter gypsum, therefore, the quality of gypsum is better, is convenient to its comprehensive utilization, simultaneously, particle diameter for lime stone requires and can relax, and can save the energy consumption of grinding stone lime stone.In addition, in waste gas absorption, absorption liquid oxidation regeneration, absorption liquid filtration and separation process, calcium sulfate in the solution is in undersaturated condition, does not have crystallization in the solution, has avoided ubiquitous fouling in conventional lime stone (lime)-gypsum, obstruction and wear phenomenon.
A kind of method that removes sulfur dioxide from waste gas comprises the steps:
A, be 4780mg/m with content of sulfur dioxide
3, amount of nitrogen oxides is 190mg/m
3, dust concentration is 150mg/m
3, temperature is that 153 ℃ waste gas passes into absorption tower 11 from air inlet 12, empty spray tower is adopted on absorption tower 11, waste gas is 11 interior risings on the absorption tower, with the absorption liquid counter current contacting that sprays from tower distributor 13, absorption liquid employing 60%(volumn concentration) mixed solution of petrolenum sulfoxide and 40% water composition, removed the waste gas of sulfur dioxide through discharging absorption tower 11 behind the demister 16, cleaned with fresh water on demister 16 tops.
B, collect and be stored in the absorption liquid storage tank 22 from the absorption liquid that absorption tower 11 top sprays get off, absorption liquid storage tank 22 is positioned at the bottom on absorption tower 11, in absorption liquid storage tank 22 bottoms air sparger 23 is set, the air that oxidation air blower fan 21 provides is evenly distributed on the bottom of absorption liquid storage tank 22 by air sparger 23, the oxidizing sulfur dioxide that absorbs on the organic absorbent is become sulfur trioxide, sulfur trioxide and water reaction generate sulfuric acid, thereby absorbent is regenerated, absorption liquid in the absorption liquid storage tank 22 is delivered to lower floor's nozzle of the distributor 13 on 11 tops, absorption tower by circulated sprinkling pump 24, continue circulated sprinkling.
C, pH value and suspension content in order to keep absorption liquid to suit, absorption liquid filter pump 31 is extracted the part absorption liquid out from absorption liquid storage tank 22, be transported to filter 32, in order to reduce the loss of organic absorbent, used filter 32 is to develop specially approximately 0.5 micron of the filtering accuracy of filter, adopt and be interrupted mode of operation, stop to filter after filter 32 interior filter cakes reach certain thickness, and purge with 0.6MPa compressed air, the solid content of filter cake reaches more than 90% after purging.The filter cake of filter 32 is sent processing outside, the filtrate of filter 32 enters knockout drum 33, then be divided into upper organic phase and lower floor's water in knockout drum 33 interior sedimentations, the absorption liquid that organic phase enters upstream absorption liquid supplementary units replenishes tank 63, and water enters the crystallization tank 41 of gypsum crystallization unit, downstream.
D, enter crystallization tank 41 from the water of knockout drum 33, mixing down, the sulfate ion of aqueous phase and the lime stone slurry generation chemical reaction that comes from the lime white supply system generate the gypsum thin pulp.Inexcessive in order to guarantee calcium carbonate, the pH value in the crystallization tank 41 is controlled at 5.5-6, calcium carbonate is all dissolved, limestone granularity is 100 orders, lime stone slurry concentration 20%, 80 rev/mins of mixing speeds.
E, the gypsum thin pulp that forms in the gypsum crystallization unit are extracted out by gypsum excavationg pump 51, deliver to gypsum eddy flow thickener, with gypsum thin pulp concentrate to moisture content approximately about 40%, then enter vacuum band-type filter machine further dewater to moisture content less than 10%, in dehydration, with the fresh water (FW) washing gypsum that comes from the gypsum washing system, remove HCl, FeCl in the gypsum
2, the soluble impurity such as silicate, finally form the finished product gypsum.The backwater of gypsum eddy flow thickener turns back to crystallization tank 41.
The Separation of Water of f, vacuum band-type filter machine enters Separation of gypsum water storage tank 61, then promoted by Separation of Water delivery pump 62, wherein a part of Separation of Water is delivered to absorption liquid and is replenished tank 63, and another part Separation of Water is discharged native system, discharges the flow of the Separation of Water of system and is regulated by control valve.Absorption liquid replenishes in the tank agitator is set, and in absorption liquid replenishes tank 63, come from that absorption liquid filters and the organic phase of separative element, come from the Separation of Water of Separation of Water delivery pump 62, and the fresh water that replenishes, by stirring formation emulsus mixed liquor.Then be transported to absorption tower 11 interior distributor 13 the superiors' nozzles of waste gas absorption unit by absorption liquid make-up pump 64.
After testing, after the said system processing, sulfur dioxide concentration is 45mg/m from the desulfurize discharge gas that absorbs the cat head discharge
3, calcium sulfate concentration 98% in the finished product gypsum, do not contain calcium sulfite.
The present invention is not particularly limited the sulfoxide type organic absorbent, in order to reduce the loss of absorbent, thereby reduction operating cost, preferably boiling point is higher than the sulfoxide of EGT, to prevent the volatilization of sulfoxide, simultaneously, for prevent or reduce the sulfoxide type organic absorbent in follow-up gypsum dehydration process with the carrying secretly or run off with the discharge of Separation of Water of gypsum, sulfoxide type absorbent that should preferably solubility is less in water.
Although described the present invention with reference to several exemplary embodiments, should be appreciated that used term is explanation and exemplary and nonrestrictive term.Because the present invention is implementation and do not break away from spirit of the present invention or essence in a variety of forms, so be to be understood that, above-described embodiment is not limited to any aforesaid details, and should be in the spirit and scope that claims limit explain widely, therefore fall into whole variations in claim or its equivalent scope and remodeling and all should be claims and contain.
Claims (12)
1. a system that removes sulfur dioxide from waste gas comprises the waste gas absorption unit, absorption liquid oxidation regeneration unit, absorption liquid filtration and separative element, gypsum crystallization unit and the gypsum dehydration unit that connect successively.
2. system according to claim 1, it is characterized in that: also comprise the absorption liquid supplementary units, described absorption liquid supplementary units is connected with gypsum dehydration unit, waste gas absorption unit.
3. system according to claim 1, it is characterized in that: described waste gas absorption unit comprises the absorption tower, is provided with air inlet in the absorption tower, is used for one or more layers distributor, demister and the gas outlet of spray-absorption liquid.
4. system according to claim 1, it is characterized in that: described absorption liquid oxidation regeneration unit comprises oxidation air blower fan, absorption liquid storage tank, circulated sprinkling pump, the flow regulator that connects successively, wherein, the absorption liquid storage tank is positioned at the bottom on absorption tower and is connected with the absorption tower, bottom at the absorption liquid storage tank is provided with air sparger, and flow regulator also is connected with the top on absorption tower.
5. system according to claim 4 is characterized in that: described absorption liquid filters and separative element comprises absorption liquid filter pump, filter, knockout drum and compressed air system.
6. system according to claim 5, it is characterized in that: described gypsum dehydration unit comprises gypsum excavationg pump, gypsum thickener, gypsum filter and gypsum washing system, wherein, described gypsum filter links to each other with the absorption liquid storage tank respectively with knockout drum.
7. system according to claim 2 is characterized in that: described absorption liquid supplementary units comprises that the Separation of gypsum water storage tank, Separation of Water delivery pump, the absorption liquid that connect successively replenish tank and absorption liquid make-up pump.
8. a right to use requires 1 described system to remove the method for sulfur dioxide from waste gas, comprises the steps:
The waste gas that a) will contain sulfur dioxide passes into the waste gas absorption unit, and waste gas is discharged from the waste gas absorption unit after contacting with absorption liquid and removing sulfur dioxide;
B) absorption liquid of step in a) is with after waste gas contacts sulfur dioxide absorption, enter absorption liquid oxidation regeneration unit, sulfur dioxide is oxidized to sulfur trioxide, and sulfur trioxide and water reaction generate sulfuric acid, absorption liquid is regenerated, and the partial regeneration absorption liquid is sent back to the waste gas absorption unit;
C) with step b) in remaining regeneration absorption liquid pass into that absorption liquid filters and separative element filters, the filtrate layering forms water and organic phase, separatory;
D) with step c) in water pass into the gypsum crystallization unit, described water mixes in the gypsum crystallization unit with the lime stone that comes from the lime white supply system or lime slurry, generates the gypsum thin pulp;
E) with steps d) described gypsum thin pulp is delivered to the gypsum dehydration unit and dewaters, and obtains gypsum and Separation of gypsum water.
9. described method according to claim 8, it is characterized in that: also comprise step c) organic phase and step e) Separation of gypsum water be delivered to respectively absorption liquid oxidation regeneration unit, both are sent to the waste gas absorption unit and reuse after absorption liquid oxidation regeneration unit mixes.
10. described method according to claim 8 is characterized in that: the calcium ion that steps d) lime stone or lime slurry provide in the gypsum crystallization unit and the mol ratio of aqueous phase sulfate ion greater than 0.5 less than 1.
11. described method according to claim 8, it is characterized in that: described absorption liquid is the mixed liquor of sulfoxide type organic absorbent and water.
12. described method according to claim 11, it is characterized in that: described sulfoxide type organic absorbent is petrolenum sulfoxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013102690204A CN103301719A (en) | 2013-06-28 | 2013-06-28 | System and method for removing sulfur dioxide from exhaust gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013102690204A CN103301719A (en) | 2013-06-28 | 2013-06-28 | System and method for removing sulfur dioxide from exhaust gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103301719A true CN103301719A (en) | 2013-09-18 |
Family
ID=49127698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2013102690204A Pending CN103301719A (en) | 2013-06-28 | 2013-06-28 | System and method for removing sulfur dioxide from exhaust gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103301719A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105013259A (en) * | 2015-07-30 | 2015-11-04 | 天津霍普环保科技有限公司 | Waste gas collection and treatment device with detection function |
| CN108325371A (en) * | 2017-12-27 | 2018-07-27 | 佛山君帝环保科技有限公司 | A kind of dust recovery process of semi-dry desulphurization dedusting |
| CN109621560A (en) * | 2019-01-13 | 2019-04-16 | 上海务宝智能装备有限公司 | A kind of acid regeneration tail gas clean-up and emission-reducing process and equipment |
| CN110075697A (en) * | 2019-04-19 | 2019-08-02 | 昆明理工大学 | A method of flue gas desulfurization and resource utilization based on electrolytic manganese mine tailings |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5832712A (en) * | 1994-02-15 | 1998-11-10 | Kvaerner Asa | Method for removing carbon dioxide from exhaust gases |
| CN1712112A (en) * | 2005-06-16 | 2005-12-28 | 王站魁 | Wetting smoke dust-proof desulfurizing method |
| CN101716454A (en) * | 2009-12-17 | 2010-06-02 | 航天环境工程有限公司 | Process for desulphurizing and dedusting catalytic cracking regenerated smoke |
| CN102500211A (en) * | 2011-09-30 | 2012-06-20 | 合肥宁垣工程技术有限责任公司 | Improved desulfuration method and device |
| CN203315977U (en) * | 2013-06-28 | 2013-12-04 | 美景（北京）环保科技有限公司 | System for removing sulfur dioxide from exhaust gas |
-
2013
- 2013-06-28 CN CN2013102690204A patent/CN103301719A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5832712A (en) * | 1994-02-15 | 1998-11-10 | Kvaerner Asa | Method for removing carbon dioxide from exhaust gases |
| CN1712112A (en) * | 2005-06-16 | 2005-12-28 | 王站魁 | Wetting smoke dust-proof desulfurizing method |
| CN101716454A (en) * | 2009-12-17 | 2010-06-02 | 航天环境工程有限公司 | Process for desulphurizing and dedusting catalytic cracking regenerated smoke |
| CN102500211A (en) * | 2011-09-30 | 2012-06-20 | 合肥宁垣工程技术有限责任公司 | Improved desulfuration method and device |
| CN203315977U (en) * | 2013-06-28 | 2013-12-04 | 美景（北京）环保科技有限公司 | System for removing sulfur dioxide from exhaust gas |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105013259A (en) * | 2015-07-30 | 2015-11-04 | 天津霍普环保科技有限公司 | Waste gas collection and treatment device with detection function |
| CN108325371A (en) * | 2017-12-27 | 2018-07-27 | 佛山君帝环保科技有限公司 | A kind of dust recovery process of semi-dry desulphurization dedusting |
| CN108325371B (en) * | 2017-12-27 | 2021-06-08 | 佛山君帝环保科技有限公司 | Dust recovery process for semi-dry desulfurization and dust removal |
| CN109621560A (en) * | 2019-01-13 | 2019-04-16 | 上海务宝智能装备有限公司 | A kind of acid regeneration tail gas clean-up and emission-reducing process and equipment |
| CN110075697A (en) * | 2019-04-19 | 2019-08-02 | 昆明理工大学 | A method of flue gas desulfurization and resource utilization based on electrolytic manganese mine tailings |
| CN110075697B (en) * | 2019-04-19 | 2021-06-22 | 昆明理工大学 | Flue gas desulfurization and resource utilization method based on electrolytic manganese tailing slag |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2586517B1 (en) | Flue gas desulfurization | |
| CN101579602B (en) | Energy-saving and high-quality ammonia desulphurization process for ammonia sulfate recovery | |
| CN100496675C (en) | Simultaneous desulfurization and denitration wet ammonia flue gas cleaning technology and system thereof | |
| CN102974185B (en) | Modularized integrated smoke purification system and method for removing plurality of pollutants | |
| CN104923044B (en) | Smoke gas treatment system and method based on ozone | |
| RU2459655C2 (en) | Device and method of smoke fumes | |
| CN102755823B (en) | Method for desulfurizing high-sulphur boiler flue gas to prepare high-purity ammonium bisulfite | |
| CN104857835A (en) | Integrated flue gas treatment device and method | |
| CN105032138B (en) | Flue gas controller and method | |
| CN101306317A (en) | Tower top discharge type flue gas desulfurization method | |
| CN101862583B (en) | Flue gas desulfurization process suitable for sintering machine of steel mill | |
| CN103990360A (en) | Continuous concentration purification method for desulfurization by-product magnesium sulfate solution | |
| CN103977689B (en) | Device and method for removing sulfur dioxide in smoke by two-step alkalifying reproducing and sodium sulfite method | |
| EP2217351A1 (en) | Method and apparatus for the removal of carbon dioxide from a gas stream | |
| CN105457479A (en) | Flue gas desulphurization zero-emission resource disposal system and method | |
| CN105080327A (en) | Method for desulfurizing and recovering NOx with alkali liquor | |
| CN103301719A (en) | System and method for removing sulfur dioxide from exhaust gas | |
| CN203315977U (en) | System for removing sulfur dioxide from exhaust gas | |
| CN113856441B (en) | Ammonia desulfurization method and ammonia desulfurization apparatus | |
| CN101829489A (en) | Ammonia-plaster mode desulphurization system | |
| CN205461713U (en) | Super clean endless integrated device of organic catalysis of coal fired boiler flue gas low temperature | |
| CN105032173A (en) | Device and process of ammonia-soda-process combined desulfurization and denitrification | |
| CN101628199A (en) | Improved magnesium method flue gas desulphurization technique | |
| CN101085411A (en) | Device and method for purifying flue gas | |
| CN105833678A (en) | Method for desulfurization of coal-fired boiler flue gas with assistance of desorption waste liquid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C05 | Deemed withdrawal (patent law before 1993) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20130918 |