CN206989168U - A kind of boiler smoke minimum discharge device - Google Patents
A kind of boiler smoke minimum discharge device Download PDFInfo
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- CN206989168U CN206989168U CN201720839594.4U CN201720839594U CN206989168U CN 206989168 U CN206989168 U CN 206989168U CN 201720839594 U CN201720839594 U CN 201720839594U CN 206989168 U CN206989168 U CN 206989168U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
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Abstract
The utility model discloses a kind of boiler smoke minimum discharge device, including coal-burning boiler, out of stock reactor, sack cleaner and desulfurizing tower, coal-burning boiler includes burner hearth, main burner and flue, and main burner is arranged on the bottom of burner hearth, and the top of burner hearth is provided with two layers of fire air nozzle；Flue gas fairlead road is offered in flue between higher level's economizer and higher level's air preheater and flue gas introduces pipeline, connects the entrance and exit of Benitration reactor respectively, the outlet of flue is sequentially connected sack cleaner and desulfurizing tower；Washing section, absorber portion and demisting section are disposed with desulfurizing tower from top to bottom, two layers of washing spraying layer is provided with above absorber portion, PP packing layers are provided between upper water washing and spraying layer and lower floor's washing spraying layer, demisting section is disposed with tubular demister and ridge demister from top to bottom.The utility model can reduce the NO in boiler smokeX、SO2And smoke content, meet national minimum discharge standard, realization device long-term operation target.
Description
Technical field
It the utility model is related to flue gases purification field, more particularly to a kind of boiler smoke minimum discharge device.
Background technology
The most of carbon emission from industry of generation of haze, the fume emission of wherein boiler is the main of atmosphere pollution
Reason.With people's living standard more and more higher, Environmental is administered increasingly strict, it is desirable to coal unit on July 1st, 2017
Later fume emission reaches minimum discharge standard（NOX＜ 50mg/m3, SO2＜ 35mg/m3, dust content ＜ 10mg/m3).
At present, the flue dust in flue gas is mainly removed by deduster, and relatively advanced dedusting method includes electric precipitation, cloth bag
Dedusting and electric bag are dust removal combined.The power consumption of electric precipitation is big, and electrode is easily grounded, and fault rate is high, it is impossible to long-term operation, dedusting
Efficiency can not produce a desired effect；The electric dust removal combined device structure of bag is complicated, and investment is larger, and maintenance rate is high；Though bag-type dust nothing
Disadvantage mentioned above, but flue dust is raised, it is necessary to coordinate other cleaners to can be only achieved discharge standard after sulfur removal technology.
Nitrogen oxides in flue gas is typically removed using SCR and SNCR Benitration reactors, and wherein SCR is used for coal-powder boiler,
SNCR is used for CFBB, but is all influenceed using which kind of denitration mode by catalyst performance, reaction efficiency and
Operational reliability is not high, NOXLasting minimum discharge can not be realized, and frequently changes catalyst economy input greatly, is only capable of cigarette
NO in gasXDropped to from 700 mg/m3 or so within 200 mg/m3, do not reach discharging standards NOX＜ 50mg/m3 are useless to urge
Agent processing can bring new environmental pressure again.
SO in flue gas2It can be removed by flue gas desulfurization technique, what is be most widely used has limestone-gypsum method（Calcium
Method）And ammonia process.Limestone-gypsum method development is more early, but investment and operating cost are higher, and enterprise is difficult to undertake.The ammonia process of desulfurization has
Have that floor space is small, small investment, do not increase carbon emission, no waste water, waste residue produce, and are adapted to a variety of coals, byproduct of ammonium sulfate profit
With higher, economic benefit clear advantage is worth, but desulfuration efficiency be present and do not reach ultralow standard, the aerosol of formation causes to take off
The shortcomings that sulphur exiting flue gas particulate matter raises.
To sum up, the minimum discharge mark of national regulation is unable to reach currently for the single denitration of flue gas, dedusting, desulfurization technology
Standard, it is extremely urgent to design new boiler flue gas purifying equipment.
Utility model content
The purpose of this utility model is to provide a kind of boiler smoke minimum discharge device, can reduced in boiler smoke
NOX、SO2And smoke content, meet national minimum discharge standard, realization device long-term operation target.
To achieve the above object, the technical solution adopted in the utility model is：
A kind of boiler smoke minimum discharge device, including coal-burning boiler, out of stock reactor, sack cleaner and desulfurizing tower,
Described coal-burning boiler includes burner hearth, main burner and flue, and described main burner is arranged on the bottom of burner hearth, main burner
Overfire air port, last wind snout, next time middle overfire air port, wind snout and lower two are inside disposed with from top to bottom
Secondary wind snout, described last wind concentrated phase side in lower section, dilute phase side up, the described concentrated phase of wind next time side up,
In lower section, described upper overfire air port area and middle overfire air port area are the 1/2 of lower overfire air port area for dilute phase side,
The top of described burner hearth is provided with two layers of fire air nozzle, respectively upper burnout degree shower nozzle and lower fire air nozzle, upper after-flame
The air port of wind snout and lower fire air nozzle is downward；
Superheater is provided with the top of described burner hearth, the outlet of the entrance connection roof of the furnace of described flue is described
Flue in be disposed with higher level's economizer, higher level's air preheater, subordinate's economizer, subordinate's air preheater and final stage empty
Air preheater, described flue offer flue gas fairlead road and cigarette respectively between higher level's economizer and higher level's air preheater
Gas introduces pipeline, and described flue gas fairlead road connects the entrance of Benitration reactor, and described flue gas introduces pipeline connection denitration
The outlet of reactor, the entrance of the outlet connection sack cleaner of described flue, the outlet of described sack cleaner passes through
Air-introduced machine connects the entrance of desulfurizing tower；
Washing section, absorber portion and demisting section are disposed with described desulfurizing tower from top to bottom, on described absorber portion
Side is provided with two layers of washing spraying layer, respectively upper water washing and spraying layer and lower floor's washing spraying layer, described upper strata water washing spray
PP packing layers are provided between drenching layer and lower floor's washing spraying layer, described demisting section is disposed with tubular type demisting from top to bottom
Device and ridge demister.
Described upper fire air nozzle and lower fire air nozzle are arranged in burner hearth by Bidirectional swinging device respectively, described
Bidirectional swinging device be used for realize fire air nozzle and lower fire air nozzle both vertically and horizontally bidirectional swinging.
Described upper fire air nozzle and the vertical range of lower burnout degree shower nozzle and last wind snout are 1.5 ~ 3m.
Described Benitration reactor is SCR denitration reactor, is provided with more than two layers catalyst in Benitration reactor, every layer
Steam soot-blower and/or sonic soot blowing device are provided with above catalyst.
Described demisting section is disposed with one layer of tubular demister and three layers of ridge demister from top to bottom.
Described upper water washing and spraying layer backwater realizes self-loopa, described lower floor washing spraying layer by one-stage water wash pump
Backwater washes pump by two level and realizes self-loopa, described tubular demister and ridge demister backwater and upper water washing and spraying layer
Backwater converges.
The utility model reduces the area of main burner inner second air spout by changing coal-burning boiler structure, and in master
Rational position sets fire air nozzle above burner, realizes boiler low nitrogen burning, NO in boiler smoke is greatly reducedX's
Generation, by and Benitration reactor combination, NO in boiler smoke can not only be metXMinimum discharge, and alleviate de-
The pressure of nitre catalyst reactor, the service life of Benitration reactor is extended, reduce equipment operating cost；
The utility model is sprayed by setting washing spraying layer and PP packing layers above the absorber portion of desulfurizing tower in washing
Layer top sets tubular demister and ridge demister, increases the internal circulating load of circulated sprinkling system, effectively eliminates in flue gas
The impurity such as the free ammonia of entrainment, water smoke, realize the qualified discharge after gas cleaning；
The utility model passes through to boiler low nitrogen burning, bag-type dust, the ammonia process of desulfurization, tube type dust removing and ridge demisting technology
It is combined realization to have complementary advantages, not only effectively reduces the NO in boiler smokeX、SO2And particle content, realize ultralow
Discharge, and input cost is few, and operational efficiency is high, highly reliable.
Brief description of the drawings
Fig. 1 is structural representation of the present utility model；
Fig. 2 is the structural representation of coal-burning boiler described in the utility model；
Fig. 3 is the structural representation of desulfurizing tower described in the utility model.
Embodiment
As shown in figure 1, a kind of boiler smoke minimum discharge device described in the utility model, including coal-burning boiler 1, denitration
Reactor 2, sack cleaner 3 and desulfurizing tower 4, flue gas caused by coal-burning boiler 1 pass sequentially through Benitration reactor 2, bag-type dust
Discharged after device 3 and desulfurizing tower 4.
As shown in Fig. 2 coal-burning boiler 1 described in the utility model includes burner hearth 5, main burner 6 and flue 7, main burning
Device 6 is arranged on the bottom of burner hearth 5, is disposed with overfire air port 8, last wind snout in main burner 6 from top to bottom
9th, middle overfire air port 10, next time wind snout 11 and lower overfire air port 12, wherein the area of upper overfire air port 8 is two with
The area of secondary wind snout 10 is the 1/2 of the area of lower overfire air port 12.Last wind concentrated phase side is in lower section, and dilute phase side is upper
Side, up, dilute phase side is advantageous to Boiler Stable Combustion, is not easy to put out a fire in lower section for wind concentrated phase side next time.
The top of burner hearth 5 described in the utility model is provided with two layers of fire air nozzle, respectively upper fire air nozzle 13
With lower fire air nozzle 14, upper fire air nozzle 13 and lower fire air nozzle 14 respectively have 4 in the present embodiment, apart from last wind
The vertical range about 3m of the center line of spout 9.Burnout degree directly by entering independent bellows after being drawn on secondary air duct, passes through air door
Control the dispatching flow and conveying isotropism of burnout degree.The air port of upper fire air nozzle 13 and lower fire air nozzle 14 is downward, point
It is not arranged on by Bidirectional swinging device in burner hearth 5, Bidirectional swinging device is used to control fire air nozzle 13 and lower burnout degree
Realize bidirectional swinging both vertically and horizontally in the air port of spout 14.When flue-gas temperature is high, Bidirectional swinging device control
Burnout degree air port moves down flame kernel to lower swing, conversely, when flue-gas temperature is low, Bidirectional swinging device control burnout degree wind
Mouth is swung up moving up flame kernel, realizes the regulation of the gentle temperature of cigarette.When left and right sides flue-gas temperature deviation is larger in burner hearth 5
When, Bidirectional swinging device control burnout degree inlet horizontal is swung, and is heated evenly boiler heating surface, is not easy booster.
The utility model reduces the inner second air area of injection orifice of main burner 6, reduces intake, coal dust is in flame kernel
Anoxycausis, then fire air nozzle is set to make coal dust after-flame above main burner 6, burnout degree air port can extend downwards flue gas
Residence time in boiler, the generation of nitrogen oxides is prevented, realize that the low nitrogen of boiler is stable and burn.The pot discharged through low nitrogen burning
NO in kiln gasXContent be less than 400mg/Nm3, due to NOXGrowing amount be greatly decreased, be effectively reduced in Benitration reactor 2
The pressure of catalyst.
The top of burner hearth 5 of the present utility model is provided with superheater 15, the outlet at the top of entrance connection burner hearth 5 of flue 7, cigarette
Higher level's economizer 16, higher level's air preheater 17, subordinate's economizer 18, the and of subordinate's air preheater 19 are disposed with road 7
Final stage air preheater 20.Flue 7 offers flue gas extraction respectively between higher level's economizer 16 and higher level's air preheater 17
Pipeline 21 and flue gas introduce pipeline 22, and flue gas fairlead road 21 connects the entrance of Benitration reactor 2, and flue gas introduces pipeline 22 and connected
The outlet of Benitration reactor 2, boiler smoke are then back to flue 7 by being reacted after higher level's economizer 16 into Benitration reactor 2
Pass sequentially through higher level's air preheater 17, subordinate's economizer 18, subordinate's air preheater 19 and the heel row of final stage air preheater 20
Go out.
Benitration reactor 2 of the present utility model is SCR denitration reactor, and three layers of catalyst are provided with Benitration reactor 2
Mounting structure, wherein two layers of installation catalyst, third layer can determine whether to add according to the detection case of remaining two layers of catalyst
Fill catalyst.Steam soot-blower and sound wave soot blower are provided with above every layer of catalyst mounting structure, is prevented by soot blowing
Only catalyst blockage.The flue-gas temperatures of 16 sections of higher level's economizer discharge are best suitable for the anti-of catalyst in Benitration reactor 2 in flue 7
Answer temperature, boiler smoke NO after Benitration reactor 2XContent be less than 50mg/Nm3。
The entrance of connection sack cleaner 3 in the outlet of flue 7 of the present utility model, the outlet of sack cleaner 3 passes through air inducing
Machine connects the entrance of desulfurizing tower 4.Wherein, sack cleaner 3 divides 12 rooms, totally 1512 cloth bags, filter area 6077m2, each
Room is provided with an Off-line valve, can realize the off-line ash-clearing and online ash removal of sack cleaner 3.Boiler smoke removes into cloth bag
Dust content before dirt device 3 is 20000mg/Nm3, the dust content after sack cleaner 3 in boiler smoke is less than 30mg/
Nm3。
As shown in figure 3, washing section 23, absorber portion are disposed with from top to bottom in desulfurizing tower 4 described in the utility model
24 and demisting section 25.Washing section 23 is provided with two layers of cooling spraying layer 26, can reduce flue-gas temperature, and heat is transmitted to from oxygen
Change the ammonium sulfate solution for entering desulfurizing tower 4 in circulating slot 27, ammonium sulfate solution is concentrated using the heat of high-temperature flue gas, obtained containing one
Obtained after the process such as the sulphur ammonium slurries of fixed solid, slurries are concentrated through cyclone, centrifuge separation, vibra fluidized bed drying, packaging
Ammonium sulfate products.
Flue gas enters absorber portion 24 after washing section 23, and absorber portion 24 is provided with three layers of absorption spraying layer 28, in flue gas
SO2Largely it is removed after absorber portion 24 reacts with absorbing liquid, while flue-gas temperature is further reduced.Absorber portion 24
Absorb the top of spraying layer 28 and be provided with two layers of washing spraying layer, respectively upper water washing and spraying layer 29 and lower floor's washing spraying layer
30, PP packing layers 31 are provided between upper water washing and spraying layer 29 and lower floor's washing spraying layer 30, upper water washing and spraying layer 29
Backwater realizes self-loopa by one-stage water wash pump, and the backwater of lower floor's washing spraying layer 30 washes pump by two level and realizes self-loopa.
Demisting section 25 is disposed with one layer of tubular demister 32 and three layers of ridge demister 33, tubular demister 32 and room from top to bottom
The backwater of the backwater of ridge demister 33 and upper water washing and spraying layer 29 converges.Washing spraying layer and combination demister can remove smoke abatement
The impurity such as free ammonia, water smoke and the particulate matter carried secretly in gas, the flue gas after purification is set to reach discharge standard.
The utility model realizes low nitrogen burning by carrying out transformation to the structure of coal-burning boiler 1, and bag-type dust, ammonia process are taken off
Sulphur, tube type dust removing and ridge demisting technology, which are combined realization, to have complementary advantages, and not only makes the boiler smoke NO after processingX＜
50mg/m3, SO2＜ 35mg/m3, dust content ＜ 10mg/m3, meet national minimum discharge standard, and plume length is 10
Rice is following.The utility model input cost is few, and operational efficiency is high, highly reliable, can realize long-term operation target.
Claims (6)
- A kind of 1. boiler smoke minimum discharge device, it is characterised in that：Including coal-burning boiler, out of stock reactor, sack cleaner And desulfurizing tower, described coal-burning boiler include burner hearth, main burner and flue, described main burner is arranged under burner hearth Portion, overfire air port, last wind snout, middle overfire air port, next time are disposed with main burner from top to bottom Wind snout and lower overfire air port, described last wind concentrated phase side is in lower section, and up, described wind next time is dense for dilute phase side Up, in lower section, described upper overfire air port area and middle overfire air port area are lower Secondary Air sprays for dilute phase side for phase side The 1/2 of open area, the top of described burner hearth are provided with two layers of fire air nozzle, respectively upper burnout degree shower nozzle and lower burnout degree The air port of spout, upper fire air nozzle and lower fire air nozzle is downward；Superheater, the outlet of the entrance connection roof of the furnace of described flue, described cigarette are provided with the top of described burner hearth It is pre- that higher level's economizer, higher level's air preheater, subordinate's economizer, subordinate's air preheater and final stage air are disposed with road Hot device, described flue offers flue gas fairlead road respectively between higher level's economizer and higher level's air preheater and flue gas draws Enter pipeline, described flue gas fairlead road connects the entrance of Benitration reactor, and described flue gas introduces pipeline connection denitration reaction The outlet of device, the entrance of the outlet connection sack cleaner of described flue, the outlet of described sack cleaner passes through air inducing Machine connects the entrance of desulfurizing tower；Washing section, absorber portion and demisting section are disposed with described desulfurizing tower from top to bottom, is set above described absorber portion It is equipped with two layers of washing spraying layer, respectively upper water washing and spraying layer and lower floor's washing spraying layer, described upper water washing and spraying layer Washed lower floor between spraying layer and be provided with PP packing layers, described demisting section be disposed with from top to bottom tubular demister and Ridge demister.
- A kind of 2. boiler smoke minimum discharge device as claimed in claim 1, it is characterised in that：Described upper fire air nozzle It is arranged on respectively by Bidirectional swinging device in burner hearth with lower fire air nozzle, described Bidirectional swinging device is used to realize combustion Use up wind snout and lower fire air nozzle both vertically and horizontally bidirectional swinging.
- A kind of 3. boiler smoke minimum discharge device as claimed in claim 2, it is characterised in that：Described upper fire air nozzle Vertical range with lower burnout degree shower nozzle and last wind snout is 1.5 ~ 3m.
- A kind of 4. boiler smoke minimum discharge device as claimed in claim 3, it is characterised in that：Described Benitration reactor is SCR denitration reactor, more than two layers catalyst is provided with Benitration reactor, steam soot blowing is provided with above every layer of catalyst Device and/or sonic soot blowing device.
- A kind of 5. boiler smoke minimum discharge device as claimed in claim 4, it is characterised in that：Described demisting section from it is lower to On be disposed with one layer of tubular demister and three layers of ridge demister.
- A kind of 6. boiler smoke minimum discharge device as claimed in claim 5, it is characterised in that；Described upper water washing and spraying Layer backwater realizes self-loopa by one-stage water wash pump, and described lower floor washes spraying layer backwater and followed certainly by two level washing pump realization Ring, described tubular demister and ridge demister backwater converge with upper water washing and spraying layer backwater.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720839594.4U CN206989168U (en) | 2017-07-12 | 2017-07-12 | A kind of boiler smoke minimum discharge device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720839594.4U CN206989168U (en) | 2017-07-12 | 2017-07-12 | A kind of boiler smoke minimum discharge device |
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| CN206989168U true CN206989168U (en) | 2018-02-09 |
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| CN201720839594.4U Active CN206989168U (en) | 2017-07-12 | 2017-07-12 | A kind of boiler smoke minimum discharge device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107270268A (en) * | 2017-07-12 | 2017-10-20 | 河南开祥精细化工有限公司 | A kind of boiler smoke minimum discharge device |
| CN109316944A (en) * | 2018-11-15 | 2019-02-12 | 湖北双环科技股份有限公司 | Water-tube boiler flue gas desulfurization device |
| CN109647158A (en) * | 2019-02-28 | 2019-04-19 | 兖矿集团有限公司 | A kind of circulating fluidized bed boiler flue gas desulfurization and denitrification system and its processing method |
-
2017
- 2017-07-12 CN CN201720839594.4U patent/CN206989168U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107270268A (en) * | 2017-07-12 | 2017-10-20 | 河南开祥精细化工有限公司 | A kind of boiler smoke minimum discharge device |
| CN109316944A (en) * | 2018-11-15 | 2019-02-12 | 湖北双环科技股份有限公司 | Water-tube boiler flue gas desulfurization device |
| CN109647158A (en) * | 2019-02-28 | 2019-04-19 | 兖矿集团有限公司 | A kind of circulating fluidized bed boiler flue gas desulfurization and denitrification system and its processing method |
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