CN112807958B - Method for simultaneously desulfurizing and denitrifying flue gas by dry method - Google Patents

Method for simultaneously desulfurizing and denitrifying flue gas by dry method Download PDF

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CN112807958B
CN112807958B CN202110076859.0A CN202110076859A CN112807958B CN 112807958 B CN112807958 B CN 112807958B CN 202110076859 A CN202110076859 A CN 202110076859A CN 112807958 B CN112807958 B CN 112807958B
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王学谦
李翔
王郎郎
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Kunming University of Science and Technology
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Abstract

The invention discloses a method for simultaneously desulfurizing and denitrating dry flue gas, which adopts a collecting pipe to collect the flue gas to be treated and uses ClO2Introducing gas into a pipeline containing flue gas to be treated or introducing ClO2Gas and flue gas to be treated are introduced into the mixing tank through the pipeline, and NO and SO are added into the flue or the mixing tank2Is covered with ClO2Oxidation to NO2And SO3(ii) a Conveying the powdery deacidification agent into a flue containing treated flue gas, thermally activating the deacidification agent by using the high temperature of the flue gas, fully contacting the deacidification agent with the flue gas to generate chemical reaction, and carrying out SO reaction on the flue gasxAnd NOxIs absorbed and purified; the treated flue gas is sent into a dust remover, dust generated in the reaction is removed, and then the flue gas is discharged, so that the desulfurization and denitrification of the flue gas are completed; the method has the advantages of simple process flow, low energy consumption, low one-time investment, low safety risk, no ammonia leakage risk, no need of heating equipment in the process flow, and low risk of fire, explosion and the like; is suitable for market and industrialized popularization and application.

Description

Method for simultaneously desulfurizing and denitrifying flue gas by dry method
Technical Field
The invention belongs to the technical field of waste gas treatment, and particularly relates to a method for simultaneously desulfurizing and denitrifying dry flue gas.
Background
With the continuous development and progress of economic society, the environmental pollution caused by energy consumption structures is becoming more serious, wherein the greenhouse effect, acid rain, atmospheric smoke pollution and the like cause serious harm to the production and life of people. In China, SO released by coal combustion285% of the total emission, NOxAccounting for 60% of the total discharge, and the amount of acid rain caused by the two accounts for 82% of the total acid rain. According to related research, the economic loss caused by acid rain pollution in China is about 5000 billions per year.
Common flue gas desulfurization techniques include wet methods (lime/limestone method, double alkali method, magnesium method, ammonia method, etc.), dry methods (electron beam radiation method, activated carbon adsorption method, etc.), and semi-dry methods (spray drying method, etc.); common flue gas denitration technologies include Selective Catalytic Reduction (SCR), selective non-catalytic reduction (SNCR), alkali liquor absorption methods and the like. From aboveFlue gas SO in developed countries in the 70 th century2On the basis of the research of emission control technology, SO in industrial flue gas is started2And NOxInvestigation of simultaneous removal. However, most of the desulfurization and denitrification integrated technologies are in research stages, and are not applied to large-scale industry.
In recent years, the steel industry commonly adopts a sodium-based dry desulphurization (SDS) and SCR method to carry out desulphurization and denitration on coke oven flue gas, namely NaHCO is firstly utilized3Mixing the superfine powder and fume at high temperature, NaHCO3Activated under the action of high-temperature flue gas, forms a microporous structure on the surface, and reacts with SO in the flue gas2And other acidic media, desulfurized and dried product Na2SO4Is collected by a bag-type dust collector. Unreacted NOx(NO content is more than 90%) enters an SCR system and is treated with NH3Is a reducing agent, and finally generates N under the action of a catalyst2And H2And discharging after O. Although the "SDS + SCR" method has been commercialized, it has some problems, such as (1) SO2And NOxTwo sets of systems are adopted for treatment, so that the process flow is long; (2) the SCR catalyst is easy to be poisoned; (3) the SCR equipment and the catalyst have high cost, and the flue gas needs to be reheated before entering the SCR, and ammonia gas needs to be consumed, so that the investment and operation cost is high.
The development technology is simple, the operation cost is low, and the desulfurization and denitrification integrated technology with good operation performance is a development direction of the future comprehensive flue gas treatment technology.
The invention with the publication number of CN 109589763A provides a method for simultaneously desulfurizing and denitrating flue gas, which adopts O3Oxidizing NO in the flue gas into high-valence nitrogen oxide, and then desulfurizing in a desulfurizing tower; then pass through O3And (4) carrying out secondary oxidation, and then carrying out desulfurization and denitrification by using 3% limestone slurry. The method adopts two steps to carry out wet desulfurization and denitration, has long process flow, large occupied area of wet equipment and complicated operation steps, and adopts O3High running cost of the generator, O3Low utilization rate, secondary pollution (nitrate waste water) and the like. Chinese utility model patents with publication numbers CN2712446Y and CN2746971Y respectively provide aThe utility model provides a flue gas desulfurization denitrification facility and SOx/NOx control integration flue gas purification tower, its SOx/NOx control equipment is the very big filler device of volume, and directly adopts aqueous ammonia solution to absorb the nitrogen oxide in the flue gas, not only makes the resistance of whole SOx/NOx control equipment increase by a wide margin, can not detach the nitrogen oxide in the flue gas effectively in addition. The reason for this is NOxThe NO accounts for more than 90 percent, and the NO is difficult to dissolve in water and is difficult to remove by adopting a simple washing method.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for simultaneously desulfurizing and denitrating dry flue gas, which can be used for desulfurizing and denitrating SO in the flue gas2And NOxMeanwhile, the method effectively removes the waste gas, shortens the process flow compared with the prior art, and directly discharges the treated flue gas.
In order to achieve the purpose, the invention adopts the following technical scheme:
(1) collecting the flue gas to be treated by adopting a collecting pipe, and collecting the ClO2Introducing gas into a pipeline containing flue gas to be treated or introducing ClO2Gas and flue gas to be treated are introduced into the mixing tank through the pipeline, and NO and SO are added into the flue or the mixing tank2Is covered with ClO2Oxidation to NO2And SO3；
(2) Conveying the powdery deacidification agent into a flue containing the flue gas treated in the step (1), thermally activating the deacidification agent by using the high temperature of the flue gas, fully contacting the flue gas to generate chemical reaction, and carrying out SO reaction on the flue gasxAnd NOxIs absorbed and purified;
(3) and (3) feeding the flue gas treated in the step (2) into a dust remover, removing dust generated in the reaction in the step (2), and then discharging to finish the desulfurization and denitrification of the flue gas.
The flue gas to be treated is coke oven flue gas, sintering flue gas of iron and steel enterprises, pellet flue gas, hot-blast stove/heat treatment furnace flue gas and the like, or flue gas with similar production and emission characteristics to the above process, and NO in the flue gas is NOxOver 90% of SO2The average concentration of (a) is 100 to 500mg/Nm3And the temperature of the flue gas is 170-320 ℃.
The smoke to be treated collected in the step (1)The gas firstly passes through a dust remover to remove most of dust and/or oily mist-like particles in the flue gas, and then is mixed with the ClO2The gas is mixed, the dust accumulation in a flue gas pipeline or a mixing tank is prevented, the on-way pressure drop is prevented from being increased, and more than 90 percent of dust and oil mist with the particle size of more than or equal to 25 mu m in the flue gas can be removed by the adopted dust removal device; the pressure loss of the dust removal system is less than or equal to 1000Pa so as to reduce the operation cost as much as possible.
The ClO2The gas is generated by adding acid into aqueous solution of chlorate or chlorite, fully mixing and reacting, a filler type circulating spray tower is adopted, the air inlet of the circulating spray tower is directly communicated with the atmosphere, and the liquid-gas ratio is 8-25L/m3(ii) a ClO in generated gas2The concentration is 500 ppm-50000 ppm, and the mixture is conveyed to a mixing tank or a flue by adopting negative pressure.
The acid is dilute sulfuric acid or dilute hydrochloric acid with the mass concentration of 1% -2%, chlorate is sodium chlorate, chlorite is sodium chlorite, and all the medicines are accurately metered by adopting a metering pump and then pumped into the ClO2In the generation device, dilute hydrochloric acid is further added into the aqueous solution of sodium chlorite, so that the raw materials can be saved to the maximum extent, and the byproducts are minimized.
5NaClO2+4HCl=4ClO2+5NaCl+2H2O
4NaClO2+2H2SO4=2ClO2+HCl+HClO3+2Na2SO4
2NaClO3+4HCl=2ClO2+Cl2+2NaCl+2H2O
4NaClO3+16HCl=2ClO2+7Cl2+4NaCl+8H2O
3NaClO3+2H2SO4=2NaHSO4+2ClO2+NaClO4+H2O；
The ClO2The reaction time of the gas and the pretreated flue gas in a flue or a mixing tank is more than 2s, if the mixing tank is adopted, the mixing tank is designed without dead zones, further, the mixing tank is suitable for adopting a vertical cylindrical tank, the tank top and the tank bottom are arched, and a gas distributor or a rotating blade can be arranged in the tank to increase gas disturbance and enable the gas to be mixed as much as possibleThe mixing is complete.
The pipeline and the mixing tank related to the step (1) and the step (2) are both a heat-insulating pipeline and a heat-insulating mixing tank; further, corrosion protection is required to be considered for all pipes, components and equipment which are in contact with the flue gas.
The powdery deacidification agent is NaHCO3、Na2CO3、MgO、CaO、CaOH、CaCO3One or more of the deacidification agents, the granularity is 20-30 mu m, the reaction temperature of the deacidification agent and the flue gas is above 140 ℃, and the reaction time is not less than 2 s; further, the stoichiometric ratio of the deacidification agent to the reactants is more than or equal to 1: 1.
In the step (2), humidity can be increased to promote NO2And a deacidification agent.
The dust remover in the step (3) is a bag-type dust remover, and the concentration of particulate matters in the flue gas after dust removal is less than or equal to 5mg/Nm3。
Cooling the flue gas subjected to dust removal in the step (3) to below 35 ℃, absorbing the flue gas by using alkali liquor, and then discharging the flue gas, wherein the alkali liquor is NaOH aqueous solution with the mass concentration of 10-30%, and the saturated solution is used for ClO2Preparation of gas, absorption of lye for removing incompletely reacted ClO2And by-product Cl2And HCl, and simultaneously realizes energy conservation and emission reduction.
2NaOH+2ClO2=NaClO2+NaClO3+H2O
2NaOH+Cl2=NaClO+NaCl+H2O (Cold water)
6NaOH + 3Cl2=5NaCl + NaClO3 + 3H2O (Hot water, > 70 ℃ C.)
NaOH+HCl=NaCl+H2O
The invention has the following beneficial effects:
(1) the invention adopts ClO2The gas not only realizes the reaction of NO and SO2Oxidation to NO2And SO3And can remove other harmful substances such as cyanide:
2ClO2 -+2CN-=2CO2+N2+2Cl-
ClO2para cyanideThe removal rate is generally more than 85 percent.
(2) The dry particulate matters collected by cloth bag dust removal after desulfurization and denitrification are mainly Na2SO4（MgSO4）、NaNO3（Mg(NO3)2）、Na2CO3(MgO) and the like, wherein, Na2SO4（MgSO4) And NaNO3（Mg(NO3)2) The mass of the material is about 80-90% of the total mass, and Na2CO3The mass of the (MgO) accounts for about 10-20% of the total mass; the by-product does not need to be separated, and can be used as a production raw material of a mine tailing curing agent and also can be used as a cement early strength agent: when the calcium sulfoaluminate is mixed into cement, the hydration product calcium sulfoaluminate is generated more quickly, and the hydration hardening speed of the cement is accelerated.
(3) According to the invention, the tail gas after desulfurization, denitrification and dust removal is washed by NaOH with the mass concentration of 10-30%, so that residual ClO in the tail gas can be basically removed2、HCl、Cl2And the like, so as to achieve the purposes of deodorization, no toxicity and no harm; furthermore, the solution obtained by washing the tail gas with NaOH mainly comprises NaClO2And NaClO3And NaClO2And NaClO3Is to produce ClO2The raw material (2) may be a solution saturated in absorption and returned to the ClO2In the production of gases for producing ClO2And the cost is saved. The above process achieves both environmental and economic benefits.
(4) The invention adopts a dry method for simultaneously desulfurizing and denitrating, and has the following advantages compared with the traditional SDS + SCR method:
a. simple process flow, NOxAnd SO2Can be removed in one step, and the process flow is shortened;
b. the energy consumption is low, the optimum reaction temperature of the SCR catalyst is 250-420 ℃, and the flue gas needs to be preheated before entering an SCR system by the traditional SDS + SCR method; the invention can realize desulfurization and denitration simultaneously only by spraying the deacidification agent into the flue, the subsequent energy consumption is not increased, and the on-way resistance is reduced and the electric energy is saved because SCR is not adopted;
c. the investment is low at one time, and the cost of SCR equipment and catalyst is saved;
d. the safety risk is low, the ammonia leakage risk is avoided, heating equipment is not needed in the process flow, and the risks of fire, explosion and the like are low.
Drawings
FIG. 1 is a process flow diagram of example 1;
FIG. 2 is a process flow diagram of example 2;
in the figure: 1-flue gas; 2-a dust remover; 3-flue gas header; 4-mixing tank; 5-ClO2A generating device; 6-acid storage tank; a 7-chlorate or chlorite storage tank; 8-acid metering pump; 9-an alkaline metering pump I; 10-circulating spray pump I; 11-an air inlet; 12-deacidifying agent powder bin; 13-deacidifying agent conveying fan; 14-bag dust collector; 15-a condenser; 16-an alkaline washing device; 17-NaOH solution storage tank; 18-alkali metering pump II; 19-circulating spray pump II; 20-a main fan; 21-purified gas.
Detailed Description
The technical solution of the present invention is further described with specific examples, but the scope of the present invention is not limited thereto.
Example 1: as shown in FIG. 1, the method for simultaneously desulfurizing and denitrating flue gas by the dry method comprises the following steps:
carrying out NO year-round on flue gas containing nitrogen oxide, sulfur dioxide and dust in coke ovens of certain iron and steel enterprises, wherein the average concentration of NO is 320mg/Nm2Average concentration about 30mg/Nm, NOxThe concentration can reach 1000mg/Nm instantly3；SO2Has an average concentration of about 110mg/Nm3(ii) a The dust content of the smoke is about 1000mg/Nm3(ii) a The flue gas temperature was 220 ℃.
(1) Flue gas pretreatment: the flue gas 1 is collected by a flue gas collecting pipe 3 lined with Teflon, and a Teflon coating can work for a long time in a high-temperature environment of 250 ℃; the bag-type dust collector 2 is used for dust collection, and the dust content after dust collection is about 5mg/Nm3The removal rate of dust with the particle size of more than or equal to 25 mu m is 99.9 percent;
（2）ClO2preparation of gas: ClO2The generating device 5 adopts a filler type circulating spray tower, the filler is Raschig rings made of PP materials, and the liquid-gas ratio is 10L/m3The lower part of the packing type circulating spray tower is provided with an air inlet 11, an acid storage tank 6 (storing hydrochloric acid with 1.3 mass percent concentration), a chlorate or chlorite storage tank 7 (storing NaClO with 2.5 mass percent concentration)2Aqueous solution) is respectively communicated with the filling type circulating spray tower through an acid metering pump 8 and an alkali metering pump I9; firstly, adopting an alkali metering pump I9 to pump NaClO with the mass concentration of 2.5 percent2The aqueous solution is conveyed to a filler type circulating spray tower, and the mass concentration of NaClO is 2.5 percent2The water solution flows into a water tank at the bottom of the tower to reach a specified liquid level; continuously adding hydrochloric acid with the mass concentration of 1.3% into a filling type circulating spray tower at the speed of 360mL/h by using an acid metering pump 8, and circularly spraying by using a circulating spray pump I10; thereby producing ClO with a concentration of 5000ppm2A gas;
(3) and (3) oxidation: adding ClO2ClO generated by the generator 52The gas is introduced into the flue gas header 3 by negative pressure, in the flue ClO2The gas and the flue gas are fully mixed, and NO is oxidized into NO2The conversion rate is 100 percent; SO (SO)2Is oxidized into SO3The conversion rate is 95 percent;
(4) and (3) simultaneous desulfurization and denitrification by a dry method: the powdered NaHCO in the deacidification agent powder bin 12 is conveyed by a deacidification agent conveying fan 13 (a high-pressure fan)3(the granularity is 20-30 mu m) is conveyed into a flue by gas power, and NaHCO is conveyed at 180 ℃ by utilizing the high temperature of the flue gas3Thermally activated and fully contacted with the flue gas to generate chemical reaction:
2NaHCO3(s)→Na2CO3(s)+H2O(g)+CO2(g)
2SO2(g)+2Na2CO3(s)+O2→2Na2SO4(s)+2CO2(g)
SO3(g)+Na2CO3(s)→Na2SO4(s)+CO2(g)
NO2(g)+Na2CO3(s)→NaNO3(s)+CO2(g)；
SO in flue gasxAnd NOxThe acidic substances are absorbed and purified;
(5) dust removal: step (a)4) The flue gas after the reaction is dedusted by a bag-type deduster 14, and Na generated by desulfurization and denitrification is removed2CO3、Na2SO4、NaNO3Collecting dust; the detection shows that the temperature of the tail gas is 140 ℃, and NO in the tail gasxConcentration 40mg/Nm3，SO2Concentration 25mg/Nm3Dust concentration of 4.5mg/Nm3Containing a small amount of ClO2Meets the GB16171-1996 emission Standard of atmospheric pollutants for coking ovens; the purified gas 21 is directly discharged into the atmosphere through a coke oven chimney by a main fan 20.
Example 2: as shown in FIG. 2, the method for simultaneously desulfurizing and denitrating flue gas by the dry method comprises the following steps:
sintering flue gas of certain iron and steel enterprises, wherein the flue gas contains nitrogen oxide, sulfur dioxide, HCl and dust, and the average concentration of NO is 300mg/Nm for NO cultivation2Performing ethanol harvest at an average concentration of about 20 mg/Nm; SO (SO)2Has an average concentration of about 300mg/Nm3(ii) a HCl concentration about 50mg/Nm3(ii) a The dust content of the smoke is about 4000mg/Nm3The temperature of the flue gas is 180 ℃;
(1) flue gas pretreatment: the flue gas 1 is collected by a flue gas collecting pipe 3 lined with Teflon, and a Teflon coating can work for a long time in a high-temperature environment of 250 ℃; the dust is removed by a bag-type dust remover 2, and the content of the smoke dust after dust removal is about 10mg/Nm3The removal rate of dust with the particle size of more than or equal to 25 mu m is 99.0 percent;
（2）ClO2preparation of gas: ClO2The generating device 5 adopts a filler type circulating spray tower, the filler is a Raschig ring made of PP material, and the liquid-gas ratio is 12L/m3The lower part of the packing type circulating spray tower is provided with an air inlet 11, an acid storage tank 6 (storing hydrochloric acid with 1.3 mass percent concentration), a chlorate or chlorite storage tank 7 (storing NaClO with 2.5 mass percent concentration)2Aqueous solution) is respectively communicated with the filling type circulating spray tower through an acid metering pump 8 and an alkali metering pump I9; firstly, adopting an alkali metering pump I9 to pump NaClO with the mass concentration of 2.5 percent2The aqueous solution is conveyed to a filler type circulating spray tower, and the NaClO with the mass concentration of 2.5 percent2The water solution flows into a water tank at the bottom of the tower to a specified liquid level; then an acid metering pump 8 is adopted to continuously add hydrochloric acid with the mass concentration of 1.3 percent into the filling type circulating spray tower at the speed of 500mL/h,circularly spraying by using a circulating spraying pump I10; thus producing ClO with a concentration of 7000ppm2A gas;
(3) and (3) oxidation: adding ClO2ClO generated by the generator 52Gas is introduced into the mixing tank 4 through negative pressure and is fully mixed with the dedusted flue gas in the mixing tank 4, and NO is oxidized into NO2The conversion rate is 100 percent; SO (SO)2Is oxidized into SO3The conversion rate is 95%;
(4) and (3) simultaneous desulfurization and denitrification by a dry method: the powdered NaHCO in the deacidification agent powder bin 12 is conveyed by a deacidification agent conveying fan 13 (a high-pressure fan)3(the granularity is 20-30 mu m) is conveyed into a flue by gas power, and NaHCO is conveyed at the high temperature of 150 ℃ by utilizing the high temperature of the flue gas3Thermally activated and fully contacted with the flue gas to generate chemical reaction:
2NaHCO3(S)→Na2CO3(s)+H2O(g)+CO2(g)
2SO2(g)+2Na2CO3(s)+O2→2Na2SO4(s)+2CO2(g)
SO3(g)+Na2CO3(s)→Na2SO4(s)+CO2(g)
NO2(g)+Na2CO3(s)→NaNO3(s)+CO2(g)
SO in flue gasxAnd NOxThe acidic substances are absorbed and purified;
(5) dust removal: the flue gas after the reaction in the step (4) is dedusted by a bag-type deduster 14, and Na generated by desulfurization and denitrification is removed2CO3、Na2SO4、NaNO3Collecting the dust with the concentration of 5mg/Nm after dust removal3；
(6) Alkali washing: the tail gas is condensed by a condenser 15 and cooled to 30 ℃, and then is introduced into an alkaline washing device 16 (a filler type spray tower) for washing, the filler adopts a Raschig ring made of PP material, the washing liquid is NaOH aqueous solution with the mass concentration of 20%, and the liquid-gas ratio is 10L/m3Conveying the NaOH aqueous solution in the NaOH solution storage tank 17 to an alkali cleaning device 16 by using an alkali metering pump II 18, and using a circulating spray pumpII 19, circularly spraying; the purified gas 21 is directly discharged into the atmosphere through a main fan 20; through detection, the temperature of the outlet tail gas is 25 ℃, and NO in the tail gasxConcentration 35mg/Nm3，SO2Concentration 30mg/Nm3Dust concentration of 4mg/Nm3HCl concentration 10mg/Nm3，ClO2Below the detection limit; meets GB28662-2012 'emission standard of atmospheric pollutants for steel sintering and pellet industry' and GB16297-1996 'comprehensive emission standard of atmospheric pollutants'.

Claims (8)

1. A method for simultaneously desulfurizing and denitrating dry flue gas is characterized by comprising the following steps:
(1) collecting flue gas to be treated by adopting flue, and introducing ClO2Introducing gas into a flue containing flue gas to be treated or introducing ClO2Introducing gas and flue gas to be treated into a mixing tank arranged on a flue through the flue, wherein NO and SO are contained in the flue or in the mixing tank2Is covered with ClO2Oxidation to NO2And SO3；
(2) Conveying the powdery deacidification agent into a flue containing the flue gas treated in the step (1), thermally activating the deacidification agent by using the high temperature of the flue gas, fully contacting the flue gas to generate chemical reaction, and carrying out SO reaction on the flue gasxAnd NOxIs absorbed and purified;
(3) feeding the flue gas treated in the step (2) into a dust remover, removing dust generated in the reaction in the step (2), and then discharging to finish the desulfurization and denitrification of the flue gas;
NO in the flue gasxOver 90% of SO2The average concentration of (a) is 100 to 500mg/Nm3The temperature of the flue gas is 170-320 ℃;
the powdery deacidification agent in the step (2) is NaHCO3、Na2CO3、MgO、CaO、Ca(OH)2 、CaCO3One or more of the deacidification agents, the granularity is 20-30 mu m, the reaction temperature of the deacidification agent and the flue gas is above 140 ℃, and the reaction time is not less than 2 s;
cooling the flue gas to below 35 ℃ after dust removal in the step (3), absorbing by using alkali liquor and then discharging, wherein the alkali liquor is in mass concentrationThe saturated solution is used for ClO, and is 10-30% NaOH aqueous solution2And (4) preparing gas.
2. The method for simultaneously desulfurizing and denitrating the dry flue gas according to claim 1, which is characterized in that: removing most of dust and/or oily mist particles in the flue gas to be treated collected in the step (1) through a dust remover, and then mixing with the ClO2And (4) mixing the gases.
3. The method for simultaneously desulfurizing and denitrating the dry flue gas according to claim 1, which is characterized in that: ClO2The gas is generated by adding acid into aqueous solution of chlorate or chlorite and fully mixing and reacting.
4. The method for simultaneously desulfurizing and denitrating the dry flue gas according to claim 3, which is characterized in that: ClO2The gas generating device is a filler type circulating spray tower, and ClO in the generated gas2The concentration is 500 ppm-50000 ppm, and the mixture is conveyed to a mixing tank or a flue by adopting negative pressure.
5. The method for simultaneously desulfurizing and denitrating the dry flue gas according to claim 3, which is characterized in that: the acid is dilute sulfuric acid or dilute hydrochloric acid with the mass concentration of 1% -2%, the chlorate is sodium chlorate, and the chlorite is sodium chlorite.
6. The method for simultaneously desulfurizing and denitrating the dry flue gas according to claim 1, which is characterized in that: ClO2The reaction time of the gas and the pretreated flue gas in a flue or a mixing tank is more than 2 s.
7. The method for simultaneously desulfurizing and denitrating the dry flue gas according to claim 1, which is characterized in that: and (3) in the step (1) and the step (2), the flue and the mixing tank are both a heat-preservation flue and a heat-preservation mixing tank.
8. The method for simultaneously desulfurizing and denitrating dry flue gas according to claim 1The method is characterized in that: the dust remover in the step (3) is a bag-type dust remover, and the concentration of particulate matters in the flue gas after dust removal is less than or equal to 5mg/Nm3。
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US7628967B2 (en) * 2002-10-01 2009-12-08 Airborne Industrial Minerals, Inc. Removal of Hg, NOx, and SOx with using oxidants and staged gas/liquid contact
CN106076106A (en) * 2016-08-02 2016-11-09 山东大学 A kind of semi-dry desulfurization and denitrification system and method based on biomass ash
CN107983119A (en) * 2017-12-05 2018-05-04 中晶环境科技股份有限公司 The dry desulfurization method of denitration of oxidation is forced based on ozone
CN110548378A (en) * 2018-06-01 2019-12-10 上海梅山钢铁股份有限公司 Method for synchronously treating sulfur dioxide and nitrogen oxide in sintering flue gas by low-temperature dry single tower
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