CN113175665A - Semi-coke low-NOx anti-slagging mixed combustion system and method - Google Patents
Semi-coke low-NOx anti-slagging mixed combustion system and method Download PDFInfo
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- CN113175665A CN113175665A CN202110426789.7A CN202110426789A CN113175665A CN 113175665 A CN113175665 A CN 113175665A CN 202110426789 A CN202110426789 A CN 202110426789A CN 113175665 A CN113175665 A CN 113175665A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C9/00—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber
- F23C9/006—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber the recirculation taking place in the combustion chamber
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
- F22D11/00—Feed-water supply not provided for in other main groups
- F22D11/02—Arrangements of feed-water pumps
- F22D11/06—Arrangements of feed-water pumps for returning condensate to boiler
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22G—SUPERHEATING OF STEAM
- F22G1/00—Steam superheating characterised by heating method
- F22G1/02—Steam superheating characterised by heating method with heat supply by hot flue gases from the furnace of the steam boiler
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23K—FEEDING FUEL TO COMBUSTION APPARATUS
- F23K1/00—Preparation of lump or pulverulent fuel in readiness for delivery to combustion apparatus
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23K—FEEDING FUEL TO COMBUSTION APPARATUS
- F23K3/00—Feeding or distributing of lump or pulverulent fuel to combustion apparatus
- F23K3/02—Pneumatic feeding arrangements, i.e. by air blast
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F23L1/00—Passages or apertures for delivering primary air for combustion
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F23L15/00—Heating of air supplied for combustion
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F23L9/00—Passages or apertures for delivering secondary air for completing combustion of fuel
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23K—FEEDING FUEL TO COMBUSTION APPARATUS
- F23K2201/00—Pretreatment of solid fuel
- F23K2201/10—Pulverizing
- F23K2201/1006—Mills adapted for use with furnaces
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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
Abstract
The invention discloses a semicoke low-NOxThe system comprises a biomass bin, a biomass drying device, a biomass pulverizer, an anti-slagging agent preparation barrel, a biomass and anti-slagging agent mixing tank, a semi-coke bin and semi-coke pulverized powderThe device comprises a semicoke-biomass mixed combustion system and an anti-slagging biomass particle preparation device, wherein the semicoke-biomass mixed combustion system comprises a machine, a boiler bottom layer combustor, a middle layer combustor, a re-combustion combustor, an over-fire air nozzle, a screen type superheater, a convection superheater, a coal economizer, a boiler tail dust remover, an oxygen preheater and the like. The invention organically combines the semicoke-biomass blending combustion system and the biomass anti-slagging particle preparation method, and improves the ignition and burnout characteristics of the semicoke and reduces NO by means of the oxygen-enriched combustion technologyxThe generation, the serious slag bonding problem of the biomass is overcome, and the CO is reduced2The waste heat and the moisture in the flue gas are fully utilized. The invention is economic and environment-friendly, simple and reliable, has wide application range and wide application prospect.
Description
Technical Field
The invention belongs to the field of clean and efficient utilization of solid carbon-based fuel, and particularly relates to semicoke low-NOxA system and a method for preventing slag-bonding mixed combustion.
Background
The coal pyrolysis byproduct semi-coke is used as a high-grade clean fuel to burn and generate power, and is an important component for realizing clean, efficient and gradient utilization of coal. With the rapid development of the coal chemical industry in China, a large amount of fuels are urgently needed to be combusted and utilized at present. However, the semi-coke has low volatile content, the realization of clean and efficient combustion is difficult, and the problems of difficult ignition and stable combustion, low burnout rate and NO exist generallyxAnd the emission is high. Therefore, how to realize clean and efficient combustion utilization of the fuel becomes a key technical bottleneck restricting the industrial application of clean and efficient gradient utilization of coal in China, and needs to be solved urgently. On the other hand, biomass energy in China is widely distributed and has little pollution, and the greenhouse effect can be effectively reduced, but because the biomass has high volatile components and contains a large amount of volatile alkaline metals and chlorine elements, serious problems related to ash content, such as slag bonding, deposition, corrosion and the like in the furnace are easily caused in the combustion process, and the large-scale utilization of the biomass is greatly restricted.
Disclosure of Invention
The invention aims to provide semicoke low-NOxThe system and the method for preventing slagging and mixed combustion are combined with an oxygen-enriched combustion technology, a mode of layered mixed combustion of biomass and semicoke in a furnace is adopted by means of slagging-resistant biomass particles, and fuel classification and oxygen classification combustion technologies are utilized to improve difficult ignition and burnout of semicoke and reduce NO of the boilerxWhen the biomass high-alkali metal slag is generated, the slag bonding problem caused by biomass high-alkali metal is relieved, the waste heat of the flue gas is fully utilized, and the water resource is saved.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
semicoke low-NOxThe anti-slagging blended combustion system comprises a semicoke-biomass blended combustion system and an anti-slagging biomass particle preparation device; wherein the content of the first and second substances,
the semicoke-biomass mixed combustion system comprises a biomass bin, a biomass drying device, a biomass pulverizer, a semicoke bin, a semicoke pulverizer, a boiler bottom burner, a middle layer burner, a re-burning burner, an over-fire air nozzle, a circulating fan, a gas mixer, a chemical treatment device, a make-up water pump, a steam turbine and a steam pump, a screen superheater, a convection superheater and an economizer which are arranged in a flue gas pipeline in sequence, and a boiler tail dust remover, an oxygen preheater, a desulfurization device, a flue gas condenser and a CO which are sequentially connected with an outlet of the flue gas pipeline2A compression device;
the anti-slagging biomass particle preparation device comprises an anti-slagging agent preparation barrel and a biomass and anti-slagging agent mixing tank;
the biomass bin is connected with an upper inlet of the biomass drying device through a conveying pipeline, an inlet of a steam pump is connected with a steam extraction pipeline of a steam turbine, an outlet of the steam pump is connected with a side inlet of the biomass drying device, an outlet of the biomass drying device is connected with an inlet of a biomass pulverizer, and an outlet of the biomass pulverizer is connected with a fuel nozzle of a boiler bottom burner; the semicoke bin is connected with an inlet of the semicoke grinding machine through a conveying pipeline, and an outlet of the semicoke grinding machine is connected with a fuel nozzle of a burner in the middle layer of the boiler; an outlet of the anti-slagging agent preparation barrel is connected with an inlet of a biomass and anti-slagging agent mixing tank, and an outlet of the biomass and anti-slagging agent mixing tank is connected with a fuel nozzle of a reburning burner;
the hot flue gas after the dust remover at the tail part of the boiler is connected with the inlet of a circulating fan through a flue gas pipeline, the outlet of the circulating fan is respectively connected with an air inlet nozzle of a reburning burner and the lower inlet of a gas mixer through a three-way valve, the inlet of an air separator is connected with the atmosphere, the lower outlet is respectively connected with a primary air nozzle of a boiler bottom burner and the side inlet of the gas mixer through the three-way valve, and the outlet of the gas mixer is respectively connected with a secondary air nozzle of the boiler bottom burner, a primary air nozzle, a secondary air nozzle and an over-fire air nozzle of a middle burner;
the condensed water outlet of the flue gas condenser is connected to the inlet of the chemical treatment device, and the outlet of the chemical treatment device is connected to the economizer through the make-up water pump.
A further development of the invention is that the biomass drying plant uses steam from a steam turbine as a drying heat source.
The invention is further improved in that the biomass mill is a fan mill, and dried biomass particles after being milled and the anti-slagging agent in the anti-slagging agent preparation barrel are mixed in a biomass and anti-slagging agent mixing tank to form the anti-slagging biomass particles.
The invention has the further improvement that dried biomass particles ground by the biomass mill and anti-slagging biomass particles in the biomass and anti-slagging agent mixing tank are respectively used as ignition fuel and reburning fuel to be sprayed into a hearth at fuel nozzles of a boiler bottom layer burner and a reburning burner, and semi-coke powder ground by the semi-coke mill is sprayed into the hearth from a fuel nozzle of a boiler middle layer burner, so that a layered combustion arrangement mode of 'combustible fuel package and non-combustible fuel' is formed.
The invention is further improved in that the primary air nozzle of the boiler bottom burner sprays oxygen separated by the air separator, the secondary air nozzle of the bottom burner, the primary air nozzle of the middle burner and the overfire air nozzle spray mixed gas of the oxygen and the circulating flue gas at the tail part of the boiler, and the secondary air nozzle of the reburning burner sprays the circulating flue gas after the dust remover at the tail part of the boiler.
The invention is further improved in that the condensed water obtained from the flue gas condenser is supplied to the economizer as boiler make-up water through a make-up water pump after being purified and deoxygenated in a chemical treatment device.
Semicoke low-NOxThe method for resisting slag bonding and blending combustion is based on the semicoke low-NOxA system for resisting slagging and co-combustion, comprising:
the biomass in the biomass bin enters a biomass drying device for drying through a conveying pipeline, and a drying heat source is derived from partial extraction steam of a steam turbine;
the dried biomass enters a biomass pulverizer to be pulverized, the pulverized biomass particles are used as ignition fuel to enter a hearth from a fuel nozzle of a boiler bottom burner, partial oxygen obtained by separation through an air separator is sprayed into the hearth from a primary air nozzle of the boiler bottom burner, and ignition and heat release of the fuel are promoted by combination of the biomass with a low ignition point and high-concentration oxygen; the secondary air required by combustion is a mixed gas of partial circulating flue gas after a dust remover at the tail part of the boiler and oxygen obtained by separation of an air separator; semi-coke in the semi-coke bin is ground by a semi-coke grinding machine and then enters a hearth from a fuel nozzle of a burner in the middle layer of the boiler, and primary air and secondary air required by combustion are mixed gas of circulating hot flue gas and oxygen;
the residual biomass particles obtained by grinding through the biomass pulverizer enter a biomass and anti-slagging agent mixing tank to prepare anti-slagging biomass particles, the anti-slagging biomass particles are used as reburning fuel to enter a hearth from a fuel nozzle of a reburning burner, primary air and secondary air required by burning are part of circulating hot smoke gas behind a dust remover at the tail part of a boiler, the anti-slagging biomass particles reburn in an oxygen-poor environment, the ash slagging rate is reduced, and NO (nitric oxide) in the burning process is reducedxGenerating;
the mixed gas of the circulating hot flue gas at the tail part of the boiler and the oxygen obtained by the separation of the air separator is sprayed into the hearth from the over-fire air nozzle, and the NO is further reduced by combining the deep classification of the fuel in the hearth, the classification of the oxygen and the local oxygen supplement at the later combustion stagexGenerating;
the flue gas after complete combustion sequentially passes through a screen superheater, a convection superheater, an economizer, a dust remover at the tail part of the boiler, an oxygen preheater, a desulfurization device, a flue gas condenser and CO2Compression plant for final CO2Sealing and storing;
oxygen separated by the air separator is preheated in the oxygen preheater and then enters the furnace to support combustion, and the boiler efficiency is improved while the waste heat of the flue gas is utilized;
condensed water obtained by the flue gas condenser is purified and deoxidized in a chemical treatment device and then is used as boiler make-up water to be supplied to the economizer through a make-up water pump.
The invention further improves that the method also comprises the following steps:
the high-temperature flue gas heats the working medium water to a superheated steam state, and the working medium water is sent into a steam turbine through a main steam pipeline to expand and do work to drive the steam turbine to rotate, and the steam turbine drives a generator to generate electricity.
The invention has the further improvement that the anti-slagging agent is a mixture of porous ceramic and dolomite powder, the mass ratio of the porous ceramic to the dolomite powder is 1:0.1-10, and the particle size of the anti-slagging agent is 1/10-1/20 of the particle size of biomass particles, so that the anti-slagging agent and the biomass particles can be synchronously suspended in a boiler hearth for combustion.
Compared with the prior art, the invention has at least the following beneficial technical effects:
the invention provides a semicoke low-NOxThe anti-slagging blended combustion system adopts a mode of combining layered blending and oxygen-enriched combustion technologies, utilizes mixed gas which is obtained by separating hot flue gas at the tail part of a boiler after dust removal from air to prepare pure oxygen to replace combustion air, can flexibly adjust the oxygen concentration according to the regional change of a combustor, replaces a traditional air preheater with an oxygen preheater arranged behind a dust remover at the tail part of the boiler, and fully utilizes the waste heat of the flue gas; collecting the purified flue gas condensate as boiler make-up water, and changing waste into valuable; the anti-slagging agent is a mixture of porous ceramic and dolomite powder, the raw material components are simple, the cost is low, the manufacturing process of the biomass anti-slagging particles is convenient and quick, and the biomass anti-slagging particles can be synchronously suspended in a boiler hearth for combustion only by controlling the particle size of each component and uniformly mixing. The anti-slagging agent can not only relieve slagging by increasing the melting point of biomass ash, but also has the effects of desulfurizing and adsorbing harmful gases.
The invention provides a semicoke low-NOxIn the process of blending and burning the semicoke and the biomass, a burning mode combining biomass anti-slagging treatment, layered blending and burning in a furnace, fuel reburning and local oxygen supplement at the later combustion is adopted, partial biomass is used as ignition fuel and is sprayed into a bottom layer burner of a hearth, pure oxygen is used as primary air, and the high-oxygen-concentration environment and the low-ignition-point characteristic can promote generationThe ignition of the substance releases heat, and the corresponding area forms an ignition area or a combustion-supporting area, and the temperature of the area is lower, and slagging and NO are combinedxThe generation is less; the semicoke is sprayed into the intermediate layer combustor, the mixed gas of the circulating flue gas and pure oxygen is used as primary air and secondary air of the semicoke, a main combustion area is formed in a corresponding area, the semicoke can be ignited by fully utilizing heat emitted by biomass combustion in the process, and the NO of the semicoke can be reduced by combining the biomass low-nitrogen content and oxygen-enriched combustion technologyxThe biomass in the area is less, and the slag bonding is less; performing anti-slagging treatment on the rest biomass, spraying part of biomass serving as reburning fuel into a hearth through a reburning burner of a boiler, taking circulating flue gas as primary air and secondary air, forming a reburning area or a gasification area in a corresponding area, reducing the slagging of the biomass by properly reducing the area temperature and anti-slagging biomass particles, and reducing NO generated by the biomass particles and the reducing gas generated by the gasification of the biomass in a main burning area by reducing semicokex(ii) a The mixed gas of the circulating flue gas and the pure oxygen is used as over-fire air, so that the combustion efficiency of the fuel is ensured; the oxygen preheater has a simple structure and a small volume, is arranged behind the dust remover at the tail part of the boiler, saves materials compared with the traditional air preheater, fully utilizes the waste heat of the flue gas, and integrally improves the efficiency of the boiler; the flue gas condensed water is used as boiler make-up water after chemical purification and deoxidization treatment, so that water resources are saved.
In conclusion, the invention solves the problems existing in the process of burning the semicoke and the biomass separately, realizes the full and gradient utilization of energy, is not limited by regions and environment, and has the advantages of simple and reliable system, economy, environmental protection and convenient management.
Drawings
Fig. 1 is a schematic diagram of the structure of the present invention.
Description of reference numerals:
1 is a biomass bin, 2 is a biomass drying device, 3 is a biomass pulverizer, 4 is a semicoke bin, 5 is the semicoke pulverizer, 6 is a slagging resistant agent preparation barrel, 7 is a biomass and slagging resistant agent mixing tank, 8 is an air separator, 9 is a gas mixer, 10 is a circulating fan, 11 is a boiler bottom layer combustor, 12 is a boiler middle layer combustor, 13 is a reburning deviceA burner, 14 is an over-fire air nozzle, 15 is a screen superheater, 16 is a convection superheater, 17 is an economizer, 18 is a dust remover at the tail part of the boiler, 19 is an oxygen preheater, 20 is a desulphurization device, 21 is a flue gas condenser, and 22 is CO2The compression device 23 is a chemical treatment device, 24 is a make-up water pump, 25 is a steam turbine, 26 is a generator, and 27 is a steam pump.
a is air, b is nitrogen, c is oxygen, d is compressed CO2And (e) sealing and disposing, wherein e is circulating flue gas.
A is an ignition area or a combustion-supporting area, B is a main combustion area, C is a reburning area or a gasification area, and D is a burnout area.
The solid line is a transportation route of solid such as semicoke, biomass and the like, the dotted line is a transportation route of gas (flue gas, steam or oxygen), and the double-dot chain line is a transportation route of make-up water.
Detailed Description
The invention is further described in detail in the following with reference to the accompanying drawings
As shown in figure 1, the semicoke low-NO-content material provided by the inventionxThe anti-slagging blended combustion system comprises a semicoke-biomass blended combustion system and an anti-slagging biomass particle preparation device.
The semicoke-biomass mixed combustion system comprises a biomass bin 1, a biomass drying device 2, a biomass mill 3, a semicoke bin 4, a semicoke mill 5, a boiler bottom layer combustor 11, a middle layer combustor 12, a reburning combustor 13, an over-fired air nozzle 14, a screen superheater 15, a convection superheater 16, an economizer 17, a boiler tail dust remover 18, an oxygen preheater 19, a circulating fan 10, a gas mixer 9, a steam turbine 25, a steam pump 27, an over-fired air pipeline, a hot flue gas pipeline and a steam pipeline.
The anti-slagging biomass particle preparation device comprises an anti-slagging agent preparation barrel 6 and a biomass and anti-slagging agent mixing tank 7.
The biomass bin 1 is connected with an upper inlet of the biomass drying device 2 through a conveying pipeline, an inlet of a steam pump 24 is connected with a steam extraction pipeline of a steam turbine 22, an outlet of a steam pump 27 is connected with a side inlet of the biomass drying device 2, an outlet of the biomass drying device 2 is connected with an inlet of a biomass mill 3, and an outlet of the biomass mill 3 is connected with a fuel nozzle of a boiler bottom layer combustor 11; the semicoke chamber 4 is connected with the inlet of the semicoke grinding machine 5 through a conveying pipeline, and the outlet of the semicoke grinding machine 5 is connected with the fuel nozzle of the boiler middle layer burner 12. The outlet of the anti-slagging agent preparation barrel 6 is connected with the inlet of the biomass and anti-slagging agent mixing tank 7, and the outlet of the biomass and anti-slagging agent mixing tank 7 is connected with a fuel nozzle of the reburning burner 13.
The part of hot flue gas behind the dust remover 18 at the tail part of the boiler is connected with the inlet of a circulating fan 10 through a flue gas pipeline, the outlet of the circulating fan 10 is respectively connected with an air inlet nozzle of a reburning burner 13 and the lower inlet of a gas mixer 9 through a three-way valve, the inlet of an air separator 8 is connected with the atmosphere, the lower outlet is respectively connected with a primary air nozzle of a boiler bottom burner 11 and the side inlet of the gas mixer 9 through a three-way valve, and the outlet of the gas mixer 9 is respectively connected with a secondary air nozzle of the boiler bottom burner 11, a primary air nozzle, a secondary air nozzle and an over-fire air nozzle 14 of a middle burner 12.
The screen superheater 15, the convection superheater 16 and the economizer 17 are sequentially arranged in the flue gas pipeline, and the boiler tail dust remover 18, the oxygen preheater 19, the desulphurization device 20, the flue gas condenser 21 and the CO2The compression device 22 is connected with the outlet of the flue gas pipeline in sequence, the condensed water outlet of the flue gas condenser 21 is connected to the inlet of the chemical treatment device 23, and the outlet of the chemical treatment device 23 is connected to the economizer 17 through the make-up water pump 24.
Further, the biomass drying device 2 uses steam from the steam turbine 25 as a drying heat source.
Further, the biomass mill 3 is a fan mill, the ground dry biomass particles and the anti-slagging agent are mixed in a biomass and anti-slagging agent mixing tank 7 to form anti-slagging biomass particles, the anti-slagging agent is a mixture of porous ceramic and dolomite powder, the mass ratio of the porous ceramic to the dolomite powder is 1:0.1-10, the particle size of the porous ceramic is 1/10-1/20 of the particle size of the biomass particles, and therefore the anti-slagging agent and the biomass particles can be synchronously suspended in a boiler hearth for combustion.
Further, dried biomass particles ground by the biomass mill 3 and anti-slagging biomass particles in the biomass and anti-slagging agent mixing tank 7 are respectively used as ignition fuel and reburning fuel to be sprayed into the hearth at fuel nozzles of a boiler bottom layer combustor 11 and a reburning combustor 13, and semi-coke powder ground by the semi-coke mill 5 is sprayed into the hearth from a fuel nozzle of a boiler middle layer combustor 12, so that a layered combustion arrangement mode of 'combustible fuel package and non-combustible fuel' is formed.
Further, the primary air nozzle of the boiler bottom burner 11 sprays oxygen separated by the air separator 8, the secondary air nozzle of the bottom burner 11, the primary air nozzle of the middle burner 12 and the overfire air nozzle 14 spray mixed gas of the oxygen and the circulating flue gas at the tail of the boiler, and the secondary air nozzle of the reburning burner 13 sprays the circulating flue gas after the dust remover 18 at the tail of the boiler.
Furthermore, an oxygen preheater with a structure simpler than that of a traditional flue gas preheater is arranged behind the dust remover 18 at the tail part of the boiler, and the waste heat of the dust-removing flue gas is used for heating oxygen entering the hearth, so that the energy loss is reduced, and the boiler efficiency is improved.
Further, the condensed water obtained from the flue gas condenser 21 is purified and deaerated in the chemical treatment device 23, and then supplied as boiler makeup water to the economizer 17 through the makeup water pump 24.
The invention relates to a low NO of ultralow volatile carbon-based fuel and lignitexThe blending burning method comprises the following steps:
1) biomass in the biomass bin 1 enters a biomass drying device 2 through a conveying pipeline for drying, and a drying heat source is derived from partial extraction steam of a steam turbine;
2) the dried biomass enters a biomass mill 3 for milling, the milled biomass particles are used as ignition fuel and enter a hearth from a fuel nozzle of a boiler bottom burner 11, partial oxygen obtained by separation through an air separator 8 is sprayed into the hearth from a primary air nozzle of the boiler bottom burner 11, and the low ignition point biomass is combined with high-concentration oxygen to promote ignition and heat release of the fuel; the secondary air required by combustion is a mixed gas of partial circulating flue gas after a dust remover 18 at the tail part of the boiler and oxygen obtained by separation through an air separator 8; semi-coke in the semi-coke bin 4 is ground by a semi-coke grinding machine 5 and then enters a hearth from a fuel nozzle of a boiler middle layer combustor 12, and primary air and secondary air required by combustion are mixed gas of circulating hot flue gas and oxygen;
3) the residual biomass particles obtained by grinding by the biomass grinding machine 3 enter a biomass and anti-slagging agent mixing tank 7 to prepare anti-slagging biomass particles, the anti-slagging biomass particles are used as reburning fuel to enter a hearth from a fuel nozzle of a reburning burner 13, primary air and secondary air required by burning are part of circulating hot flue gas behind a dust remover 18 at the tail part of a boiler, and the reburning of the anti-slagging biomass particles in an oxygen-poor environment can not only reduce the ash slagging rate, but also reduce SO in the burning process2And NOxGenerating;
4) the mixed gas of the circulating hot flue gas at the tail part of the boiler and the oxygen obtained by the separation of the air separator 8 is sprayed into the hearth from the over-fire air nozzle 14, and the NO is further reduced by combining the deep classification of the hearth fuel, the classification of the oxygen and the local oxygen supplement at the later combustion stagexGenerating;
5) the completely combusted flue gas sequentially passes through a screen superheater 15, a convection superheater 16, an economizer 17, a boiler tail dust remover 18, an oxygen preheater 19, a desulphurization device 20, a flue gas condenser 21 and CO2 A compression unit 22 for compressing CO2Sealing and storing;
6) the oxygen separated by the air separator 8 is heated in the oxygen preheater 19 and then enters the hearth for combustion supporting, and the boiler efficiency is improved while the waste heat of the flue gas is utilized;
7) the condensed water obtained by the flue gas condenser is purified and deaerated in the chemical treatment device 23, and then supplied as boiler feed water to the economizer 17 through the feed water pump 24.
8) The high-temperature flue gas heats the working medium water to a superheated steam state, and the working medium water is sent into a steam turbine 25 through a main steam pipeline to expand and do work to drive the steam turbine to rotate, and the steam turbine drives a generator 26 to generate power.
In summary, the invention utilizes the oxygen-enriched combustion technology and the anti-slagging biomass particle preparation technology, takes the dried biomass particles and the anti-slagging biomass particles as the ignition fuel and the reburning fuel respectively and forms the layered mixed combustion mode of the inflammable fuel package and the nonflammable fuel in the boiler with the semicoke, and combines the deep combustion of the oxygen in the furnace hearth fuelThe degree grading and local oxygen supplementing technology at the later combustion stage is characterized in that a hearth is divided into four combustion areas, namely a firing/combustion-supporting area, a main combustion area, a reburning/gasification area and an burnout area from bottom to top. The system design not only solves the problems of difficult burning-out of semicoke and NOxThe problem of large generation amount is solved, the serious slag bonding problem caused by high content of alkali metal in biomass is solved, and CO in the coal-fired boiler is reduced2And (4) discharging. The invention fully utilizes different grade energy, has wide application range, is economic and environment-friendly and is convenient to manage.
It should be understood that this example is only for illustrating the present invention and is not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teachings of the present invention, however, these equivalents also fall within the scope of the present invention as defined by the appended claims.
Claims (9)
1. Semicoke low-NOxThe anti-slagging blended combustion system is characterized by comprising a semicoke-biomass blended combustion system and an anti-slagging biomass particle preparation device; wherein the content of the first and second substances,
the semicoke-biomass mixed combustion system comprises a biomass bin (1), a biomass drying device (2), a biomass pulverizer (3), a semicoke bin (4), a semicoke pulverizer (5), a boiler bottom burner (11), a middle layer burner (12), a re-combustion burner (13), an over-fire air nozzle (14), a circulating fan (10), a gas mixer (9), a chemical treatment device (23), a make-up water pump (24), a steam turbine (25) and a steam pump (27), a screen superheater (15) sequentially arranged in a flue gas pipeline, a convection superheater (16) and an economizer (17), and a boiler tail dust remover (18) sequentially connected with an outlet of the flue gas pipeline, an oxygen preheater (19), a desulphurization device (20), a flue gas condenser (21) and CO2A compression device (22);
the anti-slagging biomass particle preparation device comprises an anti-slagging agent preparation barrel (6) and a biomass and anti-slagging agent mixing tank (7);
the biomass bin (1) is connected with an upper inlet of the biomass drying device (2) through a conveying pipeline, an inlet of a steam pump (27) is connected with a steam extraction pipeline of a steam turbine (25), an outlet of the steam pump (27) is connected with a side inlet of the biomass drying device (2), an outlet of the biomass drying device (2) is connected with an inlet of a biomass pulverizer (3), and an outlet of the biomass pulverizer (3) is connected with a fuel nozzle of a boiler bottom burner (11); the semicoke bin (4) is connected with an inlet of a semicoke grinding machine (5) through a conveying pipeline, and an outlet of the semicoke grinding machine (5) is connected with a fuel nozzle of a boiler middle layer combustor (12); an outlet of the anti-slagging agent preparation barrel (6) is connected with an inlet of the biomass and anti-slagging agent mixing tank (7), and an outlet of the biomass and anti-slagging agent mixing tank (7) is connected with a fuel nozzle of the reburning burner (13);
part of hot flue gas behind a dust remover (18) at the tail part of the boiler is connected with an inlet of a circulating fan (10) through a flue gas pipeline, an outlet of the circulating fan (10) is respectively connected with an air inlet nozzle of a reburning burner (13) and a lower inlet of a gas mixer (9) through a three-way valve, an inlet of an air separator (8) is connected with the atmosphere, a lower outlet is respectively connected with a primary air nozzle of a boiler bottom burner (11) and a side inlet of the gas mixer (9) through a three-way valve, and an outlet of the gas mixer (9) is respectively connected with a secondary air nozzle of the boiler bottom burner (11), a primary air nozzle and a secondary air nozzle of a middle burner (12) and an over-fire air nozzle (14);
the condensed water outlet of the flue gas condenser (21) is connected to the inlet of the chemical treatment device (23), and the outlet of the chemical treatment device (23) is connected to the economizer (17) through a make-up water pump (24).
2. The semicoke low-NO according to claim 1xThe anti-slagging and co-combustion system is characterized in that a biomass drying device (2) adopts steam from a steam turbine (25) as a drying heat source.
3. The semicoke low-NO according to claim 1xThe anti-slagging blended combustion system is characterized in that a biomass mill (3) is a fan mill, and dried biomass particles after being milled and an anti-slagging agent in an anti-slagging agent preparation barrel (6) are mixed in a biomass and anti-slagging agent mixing tank (7) to form anti-slagging biomass particles.
4. According to claim 3The semicoke is low in NOxThe anti-slagging mixed combustion system is characterized in that dried biomass particles ground by a biomass mill (3) and anti-slagging biomass particles in a biomass and anti-slagging agent mixing tank (7) are respectively used as pilot fuel and reburning fuel to be sprayed into a hearth at fuel nozzles of a boiler bottom layer combustor (11) and a reburning combustor (13), semi-coke powder ground by a semi-coke mill (5) is sprayed into the hearth from a fuel nozzle of a boiler middle layer combustor (12), and a layered combustion arrangement mode of combustible fuel package and non-combustible fuel is formed.
5. The semicoke low-NO according to claim 1xThe anti-slagging and co-combustion system is characterized in that a primary air nozzle of a boiler bottom burner (11) sprays oxygen obtained by separation of an air separator (8), a secondary air nozzle of the bottom burner (11), a secondary air nozzle of a middle burner (12) and an over-fire air nozzle (14) spray mixed gas of the oxygen and circulating flue gas at the tail part of the boiler, and a secondary air nozzle of a re-combustion burner (13) sprays the circulating flue gas after a dust remover (18) at the tail part of the boiler.
6. The semicoke low-NO according to claim 1xThe anti-slagging and co-combustion system is characterized in that condensed water obtained from a flue gas condenser (21) is purified and deoxygenated in a chemical treatment device (23) and then is used as boiler make-up water to be supplied to an economizer (17) through a make-up water pump (24).
7. Semicoke low-NOxMethod for resisting slagging and co-firing, characterized in that the method is based on the semicoke low-NO as claimed in any one of claims 1 to 6xA system for resisting slagging and co-combustion, comprising:
biomass in the biomass bin (1) enters a biomass drying device (2) through a conveying pipeline for drying, and a drying heat source is derived from partial extraction steam of a steam turbine;
the dried biomass enters a biomass pulverizer (3) for grinding, the ground biomass particles are used as ignition fuel and enter a hearth from a fuel nozzle of a boiler bottom burner (11), partial oxygen obtained by separation through an air separator (8) is sprayed into the hearth from a primary air nozzle of the boiler bottom burner (11), and the low ignition point biomass is combined with high-concentration oxygen to promote ignition and heat release of the fuel; the secondary air required by combustion is a mixed gas of partial circulating flue gas after a dust remover (18) at the tail part of the boiler and oxygen obtained by separation through an air separator (8); semi-coke in the semi-coke bin (4) is ground by a semi-coke grinding machine (5) and then enters a hearth from a fuel nozzle of a burner (12) in the middle layer of the boiler, and primary air and secondary air required by combustion are mixed gas of circulating hot flue gas and oxygen;
the residual biomass particles obtained by grinding through the biomass grinding machine (3) enter a biomass and anti-slagging agent mixing tank (7) to prepare anti-slagging biomass particles, the anti-slagging biomass particles are used as reburning fuel to enter a hearth from a fuel nozzle of a reburning burner (13), primary air and secondary air required by burning are part of circulating hot smoke gas after a dust remover (18) at the tail part of a boiler, the anti-slagging biomass particles reburn in an oxygen-poor environment, the ash slagging rate is reduced, and NO (nitric oxide) in the burning process is reducedxGenerating;
the mixed gas of the circulating hot flue gas at the tail part of the boiler and the oxygen obtained by the separation of the air separator (8) is sprayed into the hearth from the over-fire air nozzle (14), and the NO is further reduced by combining the deep classification of the fuel in the hearth, the classification of the oxygen and the local oxygen supplement at the later combustion stagexGenerating;
the completely combusted flue gas sequentially passes through a screen type superheater (15), a convection superheater (16), an economizer (17), a boiler tail dust remover (18), an oxygen preheater (19), a desulphurization device (20), a flue gas condenser (21) and CO2A compression unit (22) for compressing CO2Sealing and storing;
the oxygen separated by the air separator (8) is preheated in the oxygen preheater (19) and then enters the hearth for supporting combustion, and the boiler efficiency is improved while the waste heat of the flue gas is utilized;
condensed water obtained by the flue gas condenser is purified and deoxygenated in a chemical treatment device (23) and then supplied to the economizer (17) as boiler makeup water through a makeup water pump (24).
8. The semicoke low NO of claim 7xThe method for resisting slagging and blending combustion is characterized by also comprising the following steps:
the high-temperature flue gas heats the working medium water to a superheated steam state, the working medium water is sent into a steam turbine (25) through a main steam pipeline to expand and do work, the steam turbine (25) is driven to rotate, and the steam turbine (25) drives a generator (26) to generate electricity.
9. The semicoke low NO of claim 7xThe anti-slagging blended combustion method is characterized in that the anti-slagging agent is a mixture of porous ceramic and dolomite powder, the mass ratio of the porous ceramic to the dolomite powder is 1:0.1-10, and the particle size of the anti-slagging agent is 1/10-1/20 of the particle size of biomass particles, so that the anti-slagging agent and the biomass particles can be synchronously suspended in a hearth of a boiler for combustion.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114909660A (en) * | 2022-05-19 | 2022-08-16 | 国能龙源环保有限公司 | System and method for coupling slag drying powder making with coal-fired power plant |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102200275A (en) * | 2011-04-12 | 2011-09-28 | 上海理工大学 | Combustion device for dewatering upgradation of lignite and reduction of nitrogen oxide emission and method thereof |
| WO2012068293A2 (en) * | 2010-11-16 | 2012-05-24 | Alstom Technology Ltd | Apparatus and method of controlling the thermal performance of an oxygen-fired boiler |
| CN106439889A (en) * | 2016-11-29 | 2017-02-22 | 广东电网有限责任公司电力科学研究院 | Anthracite large oxygen-enriched combustion system and method with novel direct blowing powder production device |
| CN108151051A (en) * | 2017-11-18 | 2018-06-12 | 西安交通大学 | A kind of large scale mixes the coal-fired power station boiler system and co-combustion method for burning semicoke |
| CN108758651A (en) * | 2018-07-11 | 2018-11-06 | 中国华能集团清洁能源技术研究院有限公司 | A kind of circulating fluidized bed boiler suitable for waste incineration |
| CN109539243A (en) * | 2018-11-16 | 2019-03-29 | 西安交通大学 | A kind of system and method for biomass fuel and the mixed combustion of semicoke |
| CN109578990A (en) * | 2018-12-12 | 2019-04-05 | 西安交通大学 | A kind of low NO of pyrolysis oven-pulverized-coal fired boiler couplingxCo-combustion system and method |
| CN109990267A (en) * | 2019-04-09 | 2019-07-09 | 西安石油大学 | A kind of low NO mixing fired biomass suitable for low-volatility fuelxCombustion system |
| CN110260323A (en) * | 2019-06-26 | 2019-09-20 | 西安交通大学 | A kind of system and method that the mixed combustion of solid waste utilizes |
| CN110260352A (en) * | 2019-06-26 | 2019-09-20 | 西安交通大学 | The electric power station system and method that a kind of low NOx combustion is coupled with white cigarette abatement |
| CN111006206A (en) * | 2019-12-13 | 2020-04-14 | 华中科技大学 | Flameless classified oxygen-enriched low-NOx combustion method and system |
-
2021
- 2021-04-20 CN CN202110426789.7A patent/CN113175665B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012068293A2 (en) * | 2010-11-16 | 2012-05-24 | Alstom Technology Ltd | Apparatus and method of controlling the thermal performance of an oxygen-fired boiler |
| CN102200275A (en) * | 2011-04-12 | 2011-09-28 | 上海理工大学 | Combustion device for dewatering upgradation of lignite and reduction of nitrogen oxide emission and method thereof |
| CN106439889A (en) * | 2016-11-29 | 2017-02-22 | 广东电网有限责任公司电力科学研究院 | Anthracite large oxygen-enriched combustion system and method with novel direct blowing powder production device |
| CN108151051A (en) * | 2017-11-18 | 2018-06-12 | 西安交通大学 | A kind of large scale mixes the coal-fired power station boiler system and co-combustion method for burning semicoke |
| CN108758651A (en) * | 2018-07-11 | 2018-11-06 | 中国华能集团清洁能源技术研究院有限公司 | A kind of circulating fluidized bed boiler suitable for waste incineration |
| CN109539243A (en) * | 2018-11-16 | 2019-03-29 | 西安交通大学 | A kind of system and method for biomass fuel and the mixed combustion of semicoke |
| CN109578990A (en) * | 2018-12-12 | 2019-04-05 | 西安交通大学 | A kind of low NO of pyrolysis oven-pulverized-coal fired boiler couplingxCo-combustion system and method |
| CN109990267A (en) * | 2019-04-09 | 2019-07-09 | 西安石油大学 | A kind of low NO mixing fired biomass suitable for low-volatility fuelxCombustion system |
| CN110260323A (en) * | 2019-06-26 | 2019-09-20 | 西安交通大学 | A kind of system and method that the mixed combustion of solid waste utilizes |
| CN110260352A (en) * | 2019-06-26 | 2019-09-20 | 西安交通大学 | The electric power station system and method that a kind of low NOx combustion is coupled with white cigarette abatement |
| CN111006206A (en) * | 2019-12-13 | 2020-04-14 | 华中科技大学 | Flameless classified oxygen-enriched low-NOx combustion method and system |
Non-Patent Citations (2)
| Title |
|---|
| 王超伟等: "空气深度分级燃烧NOX排放特性的CHEMKIN模拟研究", 《燃烧科学与技术》 * |
| 董福品等: "《可再生能源概论》", 31 July 2013, 中国环境出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114909660A (en) * | 2022-05-19 | 2022-08-16 | 国能龙源环保有限公司 | System and method for coupling slag drying powder making with coal-fired power plant |
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