A kind of processing method and processing device of the flue gas containing NOx
Technical field
The invention belongs to smoke gas treatment technical fields, and in particular to a kind of processing method and processing device of the flue gas containing NOx.
Background technique
Nitrogen oxides (NOx) has N2O、NO、NO2、N2O3、N2O4And N2O5Etc. diversified forms, and a variety of harm can be caused, such as
Photochemical fog can be generated with the volatile organic matter (VOC) in atmosphere, to cause strong impulse to make in eyes, throat
With, and cause headache and respiratory disease etc., serious person will cause death.China's NOx discharge is for years more than 2000
Ten thousand tons, 2010 are 21,940,000 tons, and 2011 are 2404.3 ten thousand tons, and 2012 are 2337.8 ten thousand tons, and 2013 are 2227.3 ten thousand
Ton, 2014 are 20,780,000 tons, although continuous decreasing trend has been presented since 2012, its pollution situation is still severe.
On September 12nd, 2014, three ministries and commissions such as National Development and Reform Commission, Environmental Protection Department and National Energy Board joint publication " about print and distribute <
Coal electricity energy-saving and emission-reduction upgrading with transformation action plan (2014-2020) > notice " (hair changes the energy [2014] 2093),
It asks and " ultra-clean discharge " is carried out to fire coal boiler fume, is i.e. flue dust, SO210mg/ is respectively reached with NOx emission concentration index
Nm3、35mg/Nm3And 50mg/Nm3。
Gas denitrifying technology mainly has at present: the SCR(selective catalytic reduction of gas phase reaction)) and SNCR(selectivity
Noncatalytic reduction), liquid absorption method, solid absorption method, high energy electron active oxidation method (EBA electron beam irradiation method and PPCP
Impulse electric corona plasma method) etc..In numerous denitrating flue gas processing techniques, liquid absorption method denitration efficiency is low;Absorption method is de-
Nitre is high-efficient, but adsorbance is small, and frequently, application is not extensive for regeneration;High energy electron active oxidation method can with simultaneous SO_2 and NO removal, but
Energy consumption is high, and the service life is short;The escapement ratio of SNCR method ammonia is high, can generate safety problem.SCR technology has de- compared with other technologies
The advantages that nitre is high-efficient, technology maturation is that Flue Gas Denitrification Engineering applies most technologies both at home and abroad at present.SCR method refers to anti-
200-400 DEG C of temperature is answered, NH is used3Make reducing agent and NOx catalysis is reduced to N2, the oxygen in exhaust gas seldom participates in reaction, thermal discharge
It is small.But the reaction is in the presence of a catalyst, still needs to carry out in higher temperature, and the problems such as there are the escaping of ammonia.
Flue-gas denitration process disclosed in Chinese patent CN103768903A, CN103768932A, CN103768934A etc. needs
The flue-gas temperature for wanting 300~400 DEG C implements large-scale redevelopment to boiler, and investment cost is higher.CN102716752A discloses one
Kind low temperature SCR denitration catalyst, the catalyst is in 300ppm SO2Under the conditions of 10% water vapour content, under the conditions of 150-250 DEG C
The removal rate of NOx can keep good removal of nitrogen oxide rate in 38-72% between 150-250 DEG C.But the invention system
Standby catalyst belongs to vanadium W-Sn deposits, and ammonium metavanadate becomes V after calcining2O5, V2O5It is a kind of extremely toxic substance,
Serious pollution can be generated in production, use process.
Summary of the invention
In view of the deficiencies of the prior art, the present invention provides a kind of processing method and processing devices of flue gas containing NOx.Master of the present invention
It will be using the CO in bioanalysis removing flue gas2、NOX, without using catalyst and a large amount of chemical reagent, place good with removal effect
Manage the advantages that at low cost, economic and environment-friendly.
The processing method of present invention flue gas containing NOx, including following content:
(1) flue gas is passed through in bioreactor and is used for microdisk electrode, collect discharge gas, the microalgae is the micro- of tolerance NOx
Algae;
(2) step (1) cultivating system is separated by solid-liquid separation, respectively harvesting microalgae cell and filtrate;
(3) sodium peroxide is added in step (2) filtrate, and step (1) discharge gas is passed through in filtrate and is handled, obtains net
Change gas;
(4) step (3) Filtrate carries out denitrification processing.
In the present invention, flue gas containing NOx described in step (1) is containing NOx, CO2Flue gas, NOx is mainly NO and/or NO2, such as
It can be in the flue gases such as sulfur recovery facility incineration tail gas, catalytic cracked regenerated tail gas, coal-fired flue-gas, sintering flue gas extremely
Few one kind.When containing sulfur dioxide sulfides in flue gas, flue gas carries out desulfurization pretreatment first.According to NOx in flue gas,
CO2Multistage bioreactor can be set in content, controls CO in every grade of bioreactor2Content is lower than 45v%, preferably
5v%~35v%;NOx content is lower than 0.1v%, preferably shorter than 0.06v%;Ventilatory capacity is 0.1-1.0vvm.
In the present invention, step (1) accesses micro-algae culture medium and microalgae seed liquor, micro-algae culture medium in bioreactor
Using the fluid nutrient medium of the culture microalgae such as BG11, SE, BBM well known in the art, determined with specific reference to the type of microalgae.
The preparation of micro-algae culture medium and microalgae seed liquor is culture volume with ability conventional technical means, the inoculum concentration of microalgae seed liquor
1%~50%, preferably 5%~30%.
In the present invention, the microalgae of step (1) the tolerance NOx is the published any microalgae for being resistant to NOx, preferably
Using algae fibre (Ankistrodesmus sp.) SS-B7, the algae strain be preserved in China Microbiological on April 15th, 2013
Culture presevation administration committee common micro-organisms center, deposit number are CGMCC No. 7478, and preservation address is court, Beijing
No. 3 Institute of Microorganism, Academia Sinica, institute of positive area's North Star West Road 1.Algae strain discloses in CN 105713836A, and
Having submitted preservation and survival proves.
Further, it is preferable to access simultaneously a certain amount of chlorella (Chlorella sp.) SF-B1, the chlorella
(Chlorella sp.) to be preserved in China Committee for Culture Collection of Microorganisms on July 6th, 2015 common by SF-B1
Microorganism center, deposit number are CGMCC No. 11005, and preservation address is in Yard 1, BeiChen xi Road, Chaoyang District, Beijing City 3
Institute of microbiology, the academy of sciences, state.Frustule is green to the chlorella SF-B1 under the microscope, single-cell algae, Dan Sheng, carefully
Born of the same parents' shape is spherical and ellipse, inside there is chromatoplast, and diameter is 5-6 μm.
In the present invention, the microalgae seed liquor the preparation method is as follows: the pH of micro-algae culture medium is adjusted to 6~9, in temperature
Degree is 20~30 DEG C, and periodicity of illumination is that for 24 hours, brightness time ratio is 14:10~10:14, and intensity of illumination is 2000~10000Lux,
Shaken cultivation is to logarithmic growth phase.The volume ratio of incoming fiber algae SS-B7 seed liquor and micro-algae culture medium in bioreactor
For 1:20~1:5.As further access chlorella SF-B1, algae fibre SS-B7 seed liquor and chlorella SF-B1 seed liquor
Volume ratio is 1:1-50:1.
In the present invention, the condition of step (1) described microdisk electrode are as follows: 10~35 DEG C of temperature, periodicity of illumination for 24 hours, when brightness
Between than 10:14~14:10, pH value 6~9,2000~20000Lux of intensity of illumination, culture to growth stationary phase terminates.
In the present invention, step (2) is separated by solid-liquid separation using modes such as centrifugation, filterings, and harvesting microalgae cell and filtrate, survey respectively
Determine dry cell weight and fat content, dry cell weight can reach 10g/L or more, and fat content can reach 40% of dry cell weight or more.
In the present invention, a certain amount of sodium peroxide is added in step (3) filtrate, with specific reference to the remaining NOx in discharge gas
Content determines, it is made to be converted into nitrite, and the amount of being preferably added to is 1~30g/L.In obtained purified gas, CO2And NOx removal
Rate is up to 70% or more.If NOx removal rate is lower than 80%, step (3) purified gas is passed through step (4) denitrification processing system
In, it is further processed.
It is mainly nitrite, nitrate in step (4) filtrate in the present invention, access denitrifying bacterium carries out at denitrification
Reason, the sludge concentration after inoculation are 2000-10000mg/L.The removal efficiency of total nitrogen reaches 90% or more in water outlet.Further, excellent
A certain amount of denitrification denitrogenation bacterium is added in choosing, as marsh cock Salmonella (Kocuria palustris) FSDN-A, Coriolis grape ball
Bacterium (Staphylococcus cohnii) FSDN-C, arthrobacterium (Arthrobacter creatinolyticus) FDN-1, water
Family name's Flavobacterium (Flavobacterium mizutaiiAt least one of) FDN-2, nitrogen removal rate can achieve 95% or more.
Wherein the preservation of marsh cock Salmonella FSDN-A, Staphylococcus cohnis FSDN-C, arthrobacterium FDN-1, Shui Shi Flavobacterium FDN-2 are compiled
Number be respectively CGMCC NO.5061, CGMCC NO.5062, CGMCC No.3657, CGMCC No.3659, in
It is disclosed in CN103103141A, CN103014128A, CN102465106A, CN102465105A, and has submitted preservation and survival
It proves.
The present invention also provides a kind of devices for NOx fume treatment, including optical-biological reaction system, discharge gas to collect system
System, solid-liquid separation system, oxidative system and denilrification system, optical-biological reaction system mainly include several grades of optical-biological reactions
Device carries out microdisk electrode using the flue gas containing NOx being passed through;Gas collection system is discharged for collecting discharge gas;Solid-liquid separation system
For cultivating system to be separated by solid-liquid separation;Oxidative system is purified gas for sodium peroxide to be added;Denilrification system be used for
The filtrate arrived carries out denitrification processing.
Compared with prior art, the invention has the following advantages that
(1) using the CO in bioanalysis removing flue gas2、NOX, without using catalyst and a large amount of chemical agents, there is removing effect
The advantages that fruit is good, processing cost is low, economic and environment-friendly.
(2) using tolerance NOXMicroalgae handle flue gas, CO in flue gas2It is utilized for microalgae and generates O2, NO oxygen in flue gas
It is melted into NO2, NO is formed in water3 -And NO2 -, N is then converted in denitrification process2, above process synergistic effect, realization
CO2And NOXEfficient removal.
(3) algae fibre SS-B7 is used, NO is resistant toXPerformance is good, and carbon sequestration is high-efficient, the frustule of available high yield.Into
One step addition chlorella (Chlorella sp.) SF-B1, NOXRemoval effect it is more preferable.
(4) present invention not only can be with the processing flue gas of environmental protection and economy, but also the microalgae cell of available high fat content,
Economic benefit and environmental benefit are obviously improved.
Detailed description of the invention
Fig. 1 is the device of fume treatment of the invention;
Wherein 101- optical-biological reaction system, 102- discharge gas collection system, 103- solid-liquid separation system, 104- oxidative system,
105- denilrification system;201- culture medium and seed liquor, 202- filtrate, 203- microalgae cell, 204- sodium peroxide, 205- reaction
Filtrate afterwards, 206- water outlet;301- flue gas, 302- discharge gas, 303- purified gas.
Specific embodiment
Below by embodiment, invention is further described in detail.Embodiment is based on the technical solution of the present invention
Under implemented, the detailed implementation method and specific operation process are given, but protection scope of the present invention be not limited to it is following
Embodiment.In the present invention, v% is volume fraction.
Experimental method in following embodiment is unless otherwise specified conventional method in that art.Institute in following embodiments
Experimental material is commercially available from routine biochemistry reagent shop unless otherwise specified.
Flue gas processing device of the invention is as shown in Fig. 1, including optical-biological reaction system, discharge gas collection system, solid
Liquid separation system, oxidative system and denilrification system, wherein optical-biological reaction system 101 is a bioreactor or more
A bioreactor serial or parallel connection after micro-algae culture medium and seed liquor 201 is added, is passed through flue gas 301 and carries out microdisk electrode,
Discharge gas 302 is collected by discharge gas collection system 102;Microdisk electrode system enters solid-liquid separation system 103 and is separated, point
Other harvesting microalgae cell 203 and filtrate 202;Filtrate 202 enters oxidative system 104, and sodium peroxide 204, the row of then passing to is added
Deflation 302 is reacted, and purified gas 303 is discharged;Filtrate 205 enters denilrification system 105 and handles after reaction, must be discharged after processing
206。
Removal efficiency of the present invention is (be passed through Gas content-discharge Gas content)/it is passed through Gas content.
Microdisk electrode of the present invention uses BG11 culture medium, is formulated as shown in table 1, table 2.
1 BG11 culture medium of table
* in 2 table 1 of table A5+Co solution composition
BG11 fluid nutrient medium is prepared first, in accordance with Tables 1 and 2, pH is adjusted to 8.0, then by algae fibre SS-B7, chlorella
SF-B1 is inoculated in micro-algae culture medium, cultivates in constant temperature illumination shaking table, and cultivation temperature is 25 DEG C, and periodicity of illumination is brightness for 24 hours
Time ratio is 14:10, and intensity of illumination 5000Lux, 120rpm shaken cultivation to logarithmic growth phase obtains algae fibre SS-B7, small
Ball algae SF-B1 seed liquor.
The denitrification sludge that the embodiment of the present invention uses is derived from the denitrification processing pond in certain sewage farm, is discharged total nitrogen
Removal efficiency is up to 90% or more.
The flue gas that the present invention uses is containing NOx, CO2Flue gas, NOx is mainly NO and/or NO2.When containing dioxy in flue gas
When changing sulphur sulfides, desulfurization pretreatment is carried out first.
Embodiment 1
(1) in 10L bioreactor, the algae fibre SS-B7 seed liquor prepared and micro-algae culture medium, microdisk electrode is added
The additional amount of base is 6L, and the additional amount of seed liquor is 0.9L.It is passed through flue gas, CO in flue gas2Content be 5v%, NO content is
0.03v%, ventilatory capacity 0.5vvm.The intensity of illumination of culture is 5000Lux, and cultivation temperature is 25 DEG C, and periodicity of illumination is light for 24 hours
Dark time ratio is 14:10.In the discharge gas of collection, CO2Removal efficiency is that 85%, NO removal efficiency is 40%.
(2) after cultivating 7 days, microalgae cell and filtrate is harvested by centrifugation.Measure dry cell weight and fat content.In -60 DEG C of items
Measure algae dried bean noodles weight under part after vacuum freeze drying to constant weight, calculate yield of biomass, and use n-hexane: ethyl acetate method is surveyed
Obtain total lipid content.Dry cell weight can reach 11.7g/L after detecting, and fat content is the 43.5% of dry cell weight.
(3) sodium peroxide, additional amount 2.8g/L are added in step (2) filtrate, the discharge gas that step (1) is collected leads to
Enter in filtrate and handled, is purified gas.In purified gas, CO2Removal efficiency is that 92%, NO removal efficiency is 91%.
(4) denitrification sludge is accessed in filtrate carry out denitrification processing, sludge concentration 5000mg/L.It is discharged after processing
Middle nitrogen removal rate is up to 90% or more.
Embodiment 2
(1) in 10L bioreactor, the algae fibre SS-B7 seed liquor prepared and micro-algae culture medium, microdisk electrode is added
The additional amount of base is 6L, and the additional amount of seed liquor is 1.0L.It is passed through flue gas, CO in flue gas2Content be 10v%, NO content is
0.05v%, ventilatory capacity 0.5vvm.The intensity of illumination of culture is 5000Lux, and cultivation temperature is 25 DEG C, and periodicity of illumination is light for 24 hours
Dark time ratio is 14:10.In the discharge gas of collection, CO2Removal efficiency is that 75%, NO removal efficiency is 30%.
(2) after cultivating 8 days, microalgae cell and filtrate is harvested by centrifugation.Measure dry cell weight and fat content.In -60 DEG C of items
Measure algae dried bean noodles weight under part after vacuum freeze drying to constant weight, calculate yield of biomass, and use n-hexane: ethyl acetate method is surveyed
Obtain total lipid content.Dry cell weight can reach 11.1g/L after detecting, and fat content is the 42.2% of dry cell weight.
(3) sodium peroxide, additional amount 6.2g/L are added in step (2) filtrate, the discharge gas that step (1) is collected leads to
Enter in filtrate and handled, is purified gas.In purified gas, CO2Removal efficiency is that 88%, NO removal efficiency is 75%.
(4) denitrification sludge, sludge concentration 5000mg/L are accessed in filtrate, and step (3) purified gas is passed through instead
It answers in system and handles, obtain secondary purification gas.In secondary purification gas, CO2Removal efficiency is that 90%, NO removal efficiency is 85%.After processing
Nitrogen removal rate is up to 90% or more in water outlet.
Embodiment 3
(1) in 10L bioreactor, the algae fibre SS-B7 seed liquor prepared and micro-algae culture medium, microdisk electrode is added
The additional amount of base is 6L, and the additional amount of seed liquor is 1.2L.It is passed through flue gas, CO in flue gas2Content be 40v%, NO content is
0.05v%;Ventilatory capacity is 0.25vvm.The intensity of illumination of culture be 5000Lux, cultivation temperature be 25 DEG C, periodicity of illumination be for 24 hours,
Brightness time ratio is 14:10.In the discharge gas of collection, CO2Removal efficiency is that 55%, NO removal efficiency is 20%.
(2) after cultivating 8 days, microalgae cell and filtrate is harvested by centrifugation.Measure dry cell weight and fat content.In -60 DEG C of items
Measure algae dried bean noodles weight under part after vacuum freeze drying to constant weight, calculate yield of biomass, and use n-hexane: ethyl acetate method is surveyed
Obtain total lipid content.Dry cell weight can reach 10.7g/L after detecting, and fat content is the 41.8% of dry cell weight.
(3) sodium peroxide, additional amount 3.6g/L are added in step (2) filtrate, the discharge gas that step (1) is collected leads to
Enter in filtrate and handled, is purified gas.In purified gas, CO2Removal efficiency is that 70%, NO removal efficiency is 75%.
(4) denitrification sludge, sludge concentration 5000mg/L are accessed in filtrate, and step (3) purified gas is passed through instead
It answers in system and is handled, obtain secondary purification gas.In secondary purification gas, CO2Removal efficiency is that 75%, NO removal efficiency is 85%.Place
After reason in water outlet nitrogen removal rate up to 90% or more.
Embodiment 4
(1) CO in the flue gas used2Content be 10v%, NO content be 1.0v%, ventilatory capacity 0.3vvm.Using two-stage photoproduction
In object reactor, volume 10L is separately added into the algae fibre SS-B7 seed liquor prepared and micro-algae culture medium, micro-algae culture medium
Additional amount be 6L, the additional amount of seed liquor is 1.2L.The intensity of illumination of culture is 5000Lux, and cultivation temperature is 25 DEG C, illumination
Period is that for 24 hours, brightness time ratio is 14:10.First-stage reactor discharge gas enters second reactor.The second reactor of collection
It discharges in gas, CO2Removal efficiency is that 80%, NO removal efficiency is 35%.
(2) after cultivating 8 days, microalgae cell and filtrate is harvested by centrifugation.Measure dry cell weight and fat content.In -60 DEG C of items
Measure algae dried bean noodles weight under part after vacuum freeze drying to constant weight, calculate yield of biomass, and use n-hexane: ethyl acetate method is surveyed
Obtain total lipid content.Dry cell weight can reach 10.6g/L after detecting, and fat content is the 42.5% of dry cell weight.
(3) sodium peroxide, additional amount 3.6g/L are added in step (2) filtrate, the discharge gas that step (1) is collected leads to
Enter in filtrate and handled, is purified gas.In purified gas, CO2Removal efficiency is that 85%, NO removal efficiency is 70%.
(4) denitrification sludge, sludge concentration 5000mg/L are accessed in filtrate, and step (3) purified gas is passed through instead
It answers in device and is handled, obtain secondary purification gas.In secondary purification gas, CO2Removal efficiency is that 90%, NO removal efficiency is 80%.Processing
Afterwards in water outlet nitrogen removal rate up to 90% or more.
Embodiment 5
Using incubation and condition of culture same as Example 2, the difference is that: chlorella is added simultaneously in step (1)
SF-B1, inoculum concentration is constant, and the volume ratio of chlorella SF-B1 seed liquor and algae fibre SS-B7 seed liquor is 1:1.At step (1)
After reason, CO in the discharge gas of collection2Removal efficiency is that 75%, NO removal efficiency is 70%.The additional amount of step (3) sodium peroxide reduces close
Half, in obtained purified gas, CO2Removal efficiency is that 91%, NO removal efficiency is 88%.Without carrying out the processing of step (4).After processing
Nitrogen removal rate is up to 90% or more in water outlet.
Embodiment 6
Using incubation and condition of culture same as Example 2, the difference is that: chlorella is added simultaneously in step (1)
SF-B1, inoculum concentration is constant, and the volume ratio of chlorella SF-B1 seed liquor and algae fibre SS-B7 seed liquor is 1:5.At step (1)
After reason, CO in the discharge gas of collection2Removal efficiency is that 75%, NO removal efficiency is 60%.In obtained purified gas, CO2Removal efficiency is 90%,
NO removal efficiency is 82%.Without carrying out the processing of step (4).After processing in water outlet nitrogen removal rate up to 90% or more.
Embodiment 7
Using incubation and condition of culture same as Example 2, the difference is that: step (4) is added marsh simultaneously and examines
Kirschner bacterium (Kocuria palustris) FSDN-A, Staphylococcus cohnis (Staphylococcus cohnii) FSDN-C, section
Bacillus (Arthrobacter creatinolyticus) FDN-1, Shui Shi Flavobacterium (Flavobacterium mizutaii)
Any one in FDN-2, the same to CN103103141A, CN103014128A of the preparation method of inoculation liquid, CN102465106A,
CN102465105A, inoculum concentration are the 1% of sewage treatment system volume.In obtained purified gas, CO2Removal efficiency is 92%, NO de-
Except rate is 90%, after processing in water outlet nitrogen removal rate up to 95% or more.
Embodiment 8
Using incubation and condition of culture same as Example 2, the difference is that: CO in flue gas2Content be 10v%,
NO2Content is 0.05v%.The final effect of processing is substantially the same as embodiment 2.
Comparative example 1
Using incubation and condition of culture same as Example 1, the difference is that: using described in CN102311921A
Chlorella FY1#, due to not tolerating NOX, therefore mortality after a period of time is grown, subsequent process can not be carried out.
In summary, the present invention realizes the height of flue gas using the flue gas of microdisk electrode process processing nitrogen-containing oxide
Effect processing, while available microalgae grease, economic benefit and obvious environment benefit improve.