A kind of semi-dry desulfurization and denitrification system based on biomass ash
Technical field
This utility model belongs to gas pollution control field, particularly relates to a kind of semi-dry desulphurization based on biomass ash
Denitrating system.
Background technology
Biomass are important steps indispensable in China's energy resource structure.Biomass direct combustion power generation is biomass energy scale
Change the important channel utilized, paid attention to by everybody due to advantages such as the quality of power supply are good, reliability is high, pollution is few.Biomass
The pollutant that burning produces are mainly SO2, NOx and dirt, but owing to biomass material sulfur, nitrogen content are low, SO in flue gas2Contain with NOx
Amount is general at 100-250mg/Nm3.Dust arrester is the most only installed by traditional biomass power plant, it is not necessary to consider SO2Control with NOx
System.China " fossil-fuel power plant atmospheric pollutant emission standard GB-13223-2011 " defines the fume emission limit of biomass electric power plant
Value, SO2Emission limit is 100mg/Nm3(original unit 200mg/Nm3), NOx emission limit value is 100mg/Nm3.Additionally, emphasis
Area is gradually carried out the ultra-clean discharge standard of flue gas: SO2For 35mg/Nm3, NOx is 50mg/Nm3.This will cause biomass electric power plant SO2
With NOx discharge beyond standards, biomass electric power plant needs to carry out desulphurization denitration technological transformation.
Tradition Pollutant Control Technology, mainly by alkaline absorbent (calcio, sodio, magnesio) and SO in flue gas2Anti-
SO should be realized2Removing;Use low-NO_x combustion technology to combine SNCR or SCR technique and realize the removing of NOx.This kind of desulphurization denitration work
Technology is ripe, has obtained large-scale popularization and application in coal-burning power plant, but has been required to consume a large amount of foreign substance, produces useless simultaneously
Water and solid waste, and these waste water and solid waste also need to put into human and material resources, financial resources process.
Biomass ash typically contains the alkaline matters such as potassium oxide, sodium oxide, calcium oxide and magnesium oxide, according to its physics
Chemical property, these alkaline matters all can be with the SO in flue gas2、NO2React and realize the de-of sulfur and nitrogen oxides
Remove.And owing to first flue gas to be carried out dust removal process in existing flue gas desulfurization and denitration method, and will be raw in dust removal process
The biomass ash that substance combustion generates removes, then when carrying out desulphurization denitration, it is impossible to effectively utilize the biomass ash in flue gas, cause
The waste of the energy.
Utility model content
The purpose of this utility model is the defect overcoming tradition flue gas desulfurization and denitrification to exist, and proposes a kind of based on biomass
The semi-dry desulfurization and denitrification system of ash, this semi-dry desulfurization and denitrification system has only to adjust the system of traditional desulphurization denitration
Can carry out after whole, it is not necessary to carry out big adjustment, meet the theory of environmental protection.
Another purpose of the present utility model is to provide a kind of semi-dry desulfurization and denitrification method based on biomass ash, the party
First original is carried out dedusting by method to flue gas, then carries out desulphurization denitration, changes into carrying out first with the biomass ash in flue gas
Desulphurization denitration, then flue gas is carried out dedusting, by simple improvement sequentially, it is achieved SO in flue gas2Concentration of emission with NOx
Controlling, and owing to being semi-dry desulfurization and denitrification, will not generate waste water, the dust of collection can also reclaim, and participates in desulphurization denitration
Reaction.
3rd purpose of the present utility model is to provide above-mentioned semi-dry desulfurization and denitrification method and takes off at biomass combustion flue gas
Application in sulfur denitration.
In order to solve above technical problem, the technical solution of the utility model is:
A kind of semi-dry desulfurization and denitrification system based on biomass ash, including oxidation unit, semidry method purifying column, cleaner unit
And chimney, oxidation unit all connects with semidry method depurator with biomass combustion flue gas source, the oxidant that oxidation unit provides
Nitrogen dioxide after nitrogen oxides in flue gas and the sulfur dioxide in flue gas are absorbed by the biomass ash in flue gas, real
The desulphurization denitration of existing flue gas;Described cleaner unit is positioned at the downstream of semidry method depurator, is separated by the biomass ash in flue gas and removes,
Chimney is positioned at the downstream of cleaner unit, by the fume emission after dedusting.
Biomass refer to the various organisms utilizing big gas and water, soil etc. to be produced, biomass combustion by photosynthesis
Containing substantial amounts of biomass ash in the flue gas produced, biomass ash has alkalescence;In process system of the present utility model, half-dried
In method purifying column, oxidant by the nitrogen oxides in flue gas be nitrogen dioxide, nitrogen dioxide and sulfur dioxide be all acid
Gas, is removed by the biomass ash absorption of alkalescence, it is possible to reduce the dismutation reaction of nitrogen dioxide, improves the removal of nitrogen oxides
Efficiency.Biomass ash in flue gas is separated by cleaner unit, has on the one hand purified flue gas, on the other hand can be by part biological matter ash
Continue to put in semidry method depurator and reuse, improve the content of biomass ash in flue gas, make flue gas desulfurization and denitrification
Effect is significantly improved.
Traditional desulfurization denitration method is that first flue gas carries out dedusting, be then passed through in desulphurization denitration tower oxidant and
Alkaline aqueous solution, nitrogen dioxide and original sulfur dioxide of oxidized generation react with alkaline aqueous solution, are absorbed, titanium dioxide
Nitrogen can occur dismutation reaction in course of reaction, causes removal efficiency on the low side.
This utility model make use of biomass ash self-contained in flue gas, it is not necessary to it is possible to additionally incorporate alkaline adsorbent, also
Need not use substantial amounts of Water spray to adsorb, decrease waste water and the generation of solid waste during desulphurization denitration.
Preferably, the gas access end of described cleaner unit connects with the smoke outlet of semidry method depurator, cleaner unit
Solid outlet end connects with the inside of semidry method depurator.
Biomass ash is recycled, on the one hand can reduce the discharge of solid waste, on the other hand can increase
The input amount of the alkaline matter in semidry method purifying column, improves the effect of desulphurization denitration.
Preferably, a branch of the solid outlet end of described cleaner unit connects with ash-storing bin.
The unnecessary ash collected can enter ash-storing bin and store.
Preferably, described semidry method purifying column is internally provided with humidity regulation shower nozzle, humidity regulation shower nozzle by water pump with
Water tank connects.
It is further preferred that described humidity regulation shower nozzle is arranged at the lower section of the inside of semidry method purifying column, humidity regulation
The water injection direction of shower nozzle is arranged upward.
It is further preferred that described humidity regulation shower nozzle is pressure atomization shower nozzle or Double-fluid atomization nozzle.
It is further preferred that described water tank connects with Industry Waste water source.Industrial wastewater, twice laid, green can be utilized
Environmental protection.
Preferably, described semidry method depurator directly connects with biomass combustion flue gas source, and oxidation unit is clean with semidry method
Changing the internal connection of device, oxidant is directly put in semidry method depurator and carries out oxidation reaction by oxidation unit.
It is further preferred that described oxidation unit be ozonator, chlorine dioxide generator, plasma generator or
Dielectric barrier discharge generator.
Preferably, described oxidation unit between semidry method depurator and biomass combustion flue gas source, the nitrogen in flue gas
After oxide is oxidized, enters in semidry method depurator and carry out desulfurization and denitrification reaction.
This kind of mode can make the nitrogen oxides in flue gas abundant, improves the removal efficiency of nitrogen oxides.
Preferably, described cleaner unit is sack cleaner, gravel bed filter, electrostatic precipitator, magnetic dust collector, dry type
Cleaner unit, half dry type cleaner unit and wet scrubber.
A kind of semi-dry desulfurization and denitrification method based on biomass ash, comprises the steps:
Biomass combustion flue gas, under oxidant and the temperature of setting, damp condition, carries out semi-dry desulfurization and denitrification, its
In, oxidized dose of the nitrogen oxides in flue gas is oxidized to nitrogen dioxide, nitrogen dioxide and sulfur dioxide by the biomass in flue gas
Ash absorption, it is achieved desulphurization denitration.
Preferably, the flue gas after described semi-dry desulfurization and denitrification method also includes desulphurization denitration carries out the step of dedusting.
Preferably, the temperature of the flue gas in regulation semidry method depurator is 80-160 DEG C, and moisture is 6-25%.
Preferably, the mode of described oxidation is that ozone oxidation, Chlorine Dioxide Oxidation, plasma oxidation, dielectric impedance are put
The oxidation of electroxidation, solid oxidizer or liquid oxidizer oxidation.
Preferably, the ash collected in dust removal process participates in desulfurization and denitrification reaction in again putting into semidry method depurator.
It is further preferred that the flow of flue gas speed in semidry method depurator is 3-5m/s.
Preferably, the humidity regulation mode in semidry method depurator is pressure atomization regulation or twin regulation.
The application in biomass combustion flue gas desulfurization and denitrification of the above-mentioned semi-dry desulfurization and denitrification method.
The beneficial effects of the utility model are:
This utility model utilizes the alkaline matter in biomass ash to realize SO2And NO2Efficient removal, and without waste water, waste gas
With the discharge of solid waste, product enters in biomass ash with the form of solid, does not affect the utilization of biomass ash.With
Tradition desulphurization denitration technology is compared, it is not necessary to buys oxidant, need not use substantial amounts of spray aqueous alkali, has removal efficiency
Height, non-secondary pollution, not consuming the advantages such as other resources, application prospect is boundless.
Accompanying drawing explanation
Fig. 1 is the structural representation of embodiment 1 of the present utility model;
Fig. 2 is the structural representation of embodiment 2 of the present utility model.
Wherein, 1, oxidation unit, 2, semidry method purifying column, 3, cleaner unit, 4, chimney, 5, ash-storing bin, 6, water tank, 7, water
Pump.
Detailed description of the invention
The utility model is described in further detail below in conjunction with the accompanying drawings:
Embodiment 1
As it is shown in figure 1, a kind of semi-dry desulfurization and denitrification system based on biomass ash, clean including oxidation unit 1, semidry method
Changing tower 2, cleaner unit 3 and chimney 4, oxidation unit 1 connects with semidry method depurator 2, for providing, nitrogen oxides is carried out oxygen
The oxide changed, semidry method purifying column 2 connects with flue gas source, for flue gas carries out semi-dry desulfurization and denitrification, described cleaner unit 3
Being positioned at the downstream of semidry method depurator 2, for the flue gas ash removal after desulphurization denitration, chimney 4 is positioned at the downstream of cleaner unit 3, uses
Fume emission after purifying.
Described oxidation unit 1 is between semidry method depurator 2 and flue gas source, after nitric oxide in flue gas is oxidized,
Enter in semidry method depurator 2 and carry out desulfurization and denitrification reaction.
Mode of oxidizing in oxidation unit is ozone oxidation.
The gas access end of cleaner unit 3 connects with the smoke outlet of semidry method depurator 2, the solid outlet of cleaner unit 3
Hold connect internal with semidry method depurator 2.
The solid outlet end of described cleaner unit 3 also connects with ash-storing bin 5.The unnecessary ash collected can enter ash-storing bin
5 store.
Semidry method purifying column 2 is internally provided with humidity regulation shower nozzle, and humidity regulation shower nozzle is connected with water tank 6 by water pump 7.
Described humidity regulation shower nozzle is arranged at the lower section of the inside of semidry method purifying column 2, the water injection of humidity regulation shower nozzle
Direction is arranged upward.Humidity regulation shower nozzle is pressure atomization shower nozzle or Double-fluid atomization nozzle.By the water in water tank 6 is carried out
Atomization, is ejected into the inside of semidry method purifying column 2, and the flue gas within double dry cleaning tower 2 carries out humidity regulation, makes reaction more
Carry out well.
Described water tank 6 can connect with Industry Waste water source.Industrial wastewater is re-used, on the one hand decreases the row of waste water
Put, on the other hand decrease the waste of water purification.
Described cleaner unit 3 is sack cleaner, gravel bed filter, electrostatic precipitator, magnetic dust collector, dry dust removal
Device, half dry type cleaner unit and wet scrubber.
Flue gas containing biomass ash enters oxidation unit 1, and the oxidisability by material realizes the oxidation of NO in flue gas;With
Rear flue gas enters semidry method purifying column 2, and the water pump 7 from water tank 6 is sent in tower, sprays in flue gas, to the temperature of flue gas and
Humidity is adjusted;In semidry method purifying column 2, the SO under the conditions of suitable temperature and humidity, in flue gas2、NO2With biomass
Alkali substance reaction in ash and realize the removing of sulfur and nitrogen oxides;Mixing of flue gas, biomass ash and product
Compound enters cleaner unit 3 after flowing out semidry method purifying column 2, it is achieved flue gas separates with biomass ash, product, after separation
A material part is sent into and is participated in circulation in semidry method purifying column 2, and a part is sent in ash-storing bin 5 and stored;Cigarette after purification
Gas enters chimney 4 and discharges.
The temperature of the flue gas in regulation semidry method depurator 2 is 100 DEG C, and water content is 20%.
Flow of flue gas speed in semidry method depurator is 4m/s.
Humidity regulation mode in semidry method depurator is pressure atomization regulation.
The concentration of the nitrogen oxides in effluent after purification is down to 50mg/Nm3, the concentration of sulfur dioxide is down to 35mg/Nm3, it is
It is 4.0t that system runs the amount of the ash collected 1 hour.
Comparative example 1
The method of desulphurization denitration is: first through cleaner unit, biomass combustion flue gas is carried out dedusting, then by after dedusting
Flue gas be passed through desulphurization denitration tower, in desulphurization denitration tower, be passed through ozone, and open spray system, shower water is alkaline water, alkali
Property material is sodium hydroxide, and the spray rate of shower water is 10m3/h.The flowing velocity of the flue gas in desulphurization denitration tower is 4m/s,
Fume emission after desulphurization denitration.
The concentration of the nitrogen oxides in effluent after purification is 50mg/Nm3, the concentration of sulfur dioxide is 35mg/Nm3.System is transported
The amount of the ash that row is collected for 1 hour is 4.1t, produces without waste water, and the quality of the alkaline matter of use is 0.1t.
Embodiment 2
As in figure 2 it is shown, described semidry method depurator 2 directly connects with flue gas source, oxidation unit 1 and semidry method depurator 2
Internal connection, oxidant is directly put into and carries out oxidation reaction in semidry method depurator 2 by oxidation unit 1.
Described oxidation unit 1 can be ozonator.
A kind of semi-dry desulfurization and denitrification method based on biomass ash, comprises the steps:
Flue gas from flue gas source initially enters in semidry method depurator 2, and is passed through ozone in semidry method depurator 2,
The temperature and humidity of the flue gas in regulation semidry method depurator 2, carries out desulfurization and denitrification reaction;Flue gas after desulphurization denitration is from half-dried
The upper end outlet of method depurator 2 flows out, after dedusting, and discharge.
The temperature of the flue gas in regulation semidry method depurator 2 is 160 DEG C, and water content is 20%.
Flow of flue gas speed in semidry method depurator is 5m/s.
The concentration of the nitrogen oxides in effluent after purification is down to 50mg/Nm3, the concentration of sulfur dioxide is down to 35mg/Nm3, it is
It is 4.0t that system runs the amount of the ash collected 1 hour..
Comparative example 2
The method of desulphurization denitration is: first through cleaner unit, biomass combustion flue gas is carried out dedusting, then by after dedusting
Flue gas be passed through desulphurization denitration tower, in desulphurization denitration tower, be passed through ozone, and open spray system, shower water is alkaline water, alkali
Property material is sodium hydroxide, and the spray rate of shower water is 10m3/h.The flowing velocity of the flue gas in desulphurization denitration tower is 5m/s,
Fume emission after desulphurization denitration.
The concentration of the nitrogen oxides in effluent after purification is 50mg/Nm3, the concentration of sulfur dioxide is 35mg/Nm3, system is transported
The amount of the ash that row is collected for 1 hour is 4.1t, produces without waste water, and the quality of the alkaline matter of use is 0.1t/h.
Although detailed description of the invention of the present utility model is described by the above-mentioned accompanying drawing that combines, but not to utility model
The restriction of protection domain, one of ordinary skill in the art should be understood that on the basis of the technical solution of the utility model, this area
Technical staff need not to pay various amendments or deformation that creative work can make still at protection domain of the present utility model
In.