CN110822418A - Low NO of pi-shaped boiler under low loadXLow temperature flue gas recirculation system and method - Google Patents

Low NO of pi-shaped boiler under low loadXLow temperature flue gas recirculation system and method Download PDF

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Publication number
CN110822418A
CN110822418A CN201911094770.6A CN201911094770A CN110822418A CN 110822418 A CN110822418 A CN 110822418A CN 201911094770 A CN201911094770 A CN 201911094770A CN 110822418 A CN110822418 A CN 110822418A
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CN
China
Prior art keywords
low
temperature
flue gas
primary air
hot
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Pending
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CN201911094770.6A
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Chinese (zh)
Inventor
李伟
景雪晖
朱建平
唐权利
魏博
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Urumqi Electric Power Construction And Debugging Institute Xinjiang Xinneng Group Co Ltd
Xinjiang University
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Urumqi Electric Power Construction And Debugging Institute Xinjiang Xinneng Group Co Ltd
Xinjiang University
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Application filed by Urumqi Electric Power Construction And Debugging Institute Xinjiang Xinneng Group Co Ltd, Xinjiang University filed Critical Urumqi Electric Power Construction And Debugging Institute Xinjiang Xinneng Group Co Ltd
Priority to CN201911094770.6A priority Critical patent/CN110822418A/en
Publication of CN110822418A publication Critical patent/CN110822418A/en
Pending legal-status Critical Current

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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
    • F23C9/06—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber for completing combustion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J15/00—Arrangements of devices for treating smoke or fumes
    • F23J15/06—Arrangements of devices for treating smoke or fumes of coolers
    • 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
    • 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
    • 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
    • F23L7/00—Supplying non-combustible liquids or gases, other than air, to the fire, e.g. oxygen, steam
    • 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 low-temperature flue gas recirculation method for low NOx of the pi-shaped boiler under low load is characterized in that a part of flue gas is extracted from an inlet flue of a boiler economizer through a low-temperature recirculation fan to be used as low-temperature recirculation flue gas to be mixed with cold air and hot air in a cold primary air pipe and a hot primary air pipe, then mixed gas is introduced into a coal mill and carries pulverized coal to enter a combustor, and the volume ratio of each component in the mixed gas is adjusted through a cold primary air valve, a hot primary air valve and a low-temperature flue gas valve. The method comprises the following steps: the device comprises a primary fan, a low-temperature recycling fan, a coal dropping hopper, a coal mill, a burner, a hearth, an over-fire air nozzle, a screen superheater, a reheater, an economizer, an SCR catalyst layer, an air preheater, a temperature sensor, a gas mixing chamber, an oxygen meter, a hot primary air pipe, a cold primary air pipe, a low-temperature recycling flue gas pipe, a low-temperature flue gas valve, a cold primary air valve, a hot primary air valve, an electric dust remover, an induced draft fan, a desulfurizing tower and a chimney.

Description

Low NO of pi-shaped boiler under low loadXLow temperature flue gas recirculation system and method
Technical Field
The invention relates to the technical field of reduction of NOx of pi-type coal-fired boilers, in particular to a low-temperature flue gas recirculation system and a low-NOx low-temperature flue gas recirculation method for a pi-type boiler under low load.
Background
With the increase of the installed capacity of renewable energy generating sets in China, the generated energy of the coal-fired generating sets is greatly compressed, so that the load of the coal-fired boiler is lower and lower, particularly the total installed capacity of the Xinjiang coal-fired generating sets is large, the capacity of the renewable energy generating sets is rich, and the coal-fired boiler is required to improve the peak regulation capacity. Pulverized coal used for boiler combustion flows through a coal mill by primary air and is blown into a hearth. However, when the boiler operates under the low-load condition, in order to keep the powder carrying capacity, the primary air quantity cannot be reduced in equal proportion with the coal supply quantity, so that the air-coal ratio of a primary air nozzle is improved, namely the oxygen-coal ratio of a partial combustion area is improved, the combustion temperature of the area is further improved, the thermal NOx generation quantity is increased, and the NOx concentration is more than 500mg/Nm at the outlet of a hearth3。
At present, the national emission index of NOx is lower than 50mg/Nm3. Most coal-fired power generating units adopt a flue gas denitration system to remove NOx in flue gas generated during boiler combustion, however, the denitration efficiency of Selective Catalytic Reduction (SCR) is about 80-90%, so that the concentration of NOx at the inlet of the SCR is required to be not more than 500mg/Nm3。
In order to make the NOx emission concentration at the outlet of a hearth lower than 500mg/Nm3The low-nitrogen combustion mode adopted at present mainly is an air classification or fuel classification technology, namely, the primary air rate is reduced to reduce the oxygen content of a combustion area, and further, the combustion temperature is reduced to realize low-nitrogen combustion. However, under the condition of low load of the boiler, the primary air powder carrying capacity is limited, so thatThe oxygen-coal ratio is improved, and the NOx generation amount is increased. Decoupling the oxygen content and the flow of primary air, respectively controlling the primary air volume and the oxygen content, realizing that the oxygen content is reduced while the primary air volume is higher under the condition of low load of the boiler, and further achieving the purpose of reducing the generation of NOx, and the method is a problem to be solved urgently at present.
Disclosure of Invention
In order to solve the defects that the primary air powder carrying capacity of the existing coal-fired boiler is limited in the low-load operation process, the oxygen-coal ratio is improved, and the NOx generation amount is increased, the invention aims to provide the low-temperature flue gas recirculation system and the low-NOx low-temperature flue gas recirculation method for the pi-type boiler under the low load.
In order to achieve the above object, the present invention provides a low-temperature flue gas recirculation system with low NOx in pi-type boiler under low load, comprising: the system comprises a primary fan 1, a low-temperature recirculation fan 2, a coal hopper 3, a coal mill 4, a combustor 5, a hearth 6, an over-fire air nozzle 7, a platen superheater 8, a superheater 9, a reheater 10, an economizer 11, an SCR catalyst layer 12, an air preheater 13, a temperature sensor 14, a gas mixing chamber 15, an oxygen meter 16, a primary hot air pipe 17, a primary cold air pipe 18, a low-temperature recirculation flue gas pipe 19, a low-temperature flue gas valve 20, a primary cold air valve 21, a primary hot air valve 22, an electric dust remover 23, an induced draft fan 24, a desulfurizing tower 25 and a chimney 26.
The over-fire air nozzles 7 are located on the upper portion of the combustor 5, the combustor 5 and the over-fire air nozzles 7 are symmetrically distributed on four corners of the hearth 6, the coal hopper 3 is arranged above the coal pulverizer 4 and connected through a pipeline, the coal pulverizer 4 is connected with the combustor 5 through a pulverized coal pipe, and the temperature sensor 14 is located on an inlet hot air pipe of the coal pulverizer 4.
The screen superheater 8, the superheater 9 and the reheater 10 are sequentially arranged in a horizontal flue at the upper part of the hearth 6, and the economizer 11, the SCR catalyst layer 12 and the air preheater 13 are sequentially arranged in a vertical flue at the right side of the hearth 6.
The electric dust collector 23 is connected with the induced draft fan 24 through a flue outlet pipeline at the lower part of the air preheater 13, and the induced draft fan 24, the desulfurizing tower 25 and the chimney 26 are all connected with each other through pipelines in sequence.
The gas mixing chamber 15 is respectively connected with a cold primary air pipe 18, a low-temperature recycling flue gas pipe 19, a coal mill 4 and a hot primary air pipe 17, and the oxygen meter 16 is positioned on an inlet hot air pipe of the coal mill 4; the low-temperature recirculation fan 2 extracts low-temperature recirculation smoke through a pipeline, and a pipeline inlet is connected to an outlet flue of the electric dust collector 23.
The invention also provides a low-temperature flue gas recirculation method of low NOx of the pi-type boiler under low load, which is characterized in that a part of flue gas is extracted from the side surface of an inlet flue of an economizer 11 through a low-temperature recirculation fan 2 to be used as low-temperature recirculation flue gas to be mixed with cold air and hot air in a cold primary air pipe 18 and a hot primary air pipe 17, and then mixed gas is introduced into a coal mill 4 and carries coal powder to enter a combustor 5; the cold primary air quantity is adjusted through the cold primary air valve 21, the hot primary air quantity is adjusted through the hot primary air valve 22, the low-temperature flue gas quantity is adjusted through the low-temperature flue gas valve 20, and the temperature and the oxygen quantity of mixed gas at the inlet of the combustor 5 can be adjusted through the cold primary air valve, the hot primary air valve and the low-temperature flue gas valve.
Further, under the standard condition, when the load of the boiler is 30%, the volume of the mixture of the low-temperature recirculated flue gas, the cold primary air and the hot primary air accounts for 20% -30% of that of the low-temperature recirculated flue gas, the cold primary air accounts for 0% of that of the low-temperature recirculated flue gas, and the hot primary air accounts for 70% -80% of that of the low-temperature recirculated flue gas; when the load of the boiler is 40%, the volume of the mixture of the low-temperature recirculated flue gas, the cold primary air and the hot primary air accounts for 20% -30% of the volume of the low-temperature recirculated flue gas, 0% -5% of the volume of the cold primary air and 70% -80% of the volume of the hot primary air.
Further, low temperature flue gas not drawn by the low temperature recirculation fan 2 is discharged from the stack 26 through the boiler flue.
The invention has the beneficial effects that: the low-temperature recirculated flue gas is used as primary air to be mixed with cold and hot primary air in the air mixing chamber 15, and then enters the hearth 6 through the coal mill 4 to the combustor 5 for combustion supporting, the low oxygen content of the low-temperature recirculated flue gas can reduce the oxygen concentration in the hearth 6, reduce the generation of thermal NOx, reduce the heat loss of the boiler and improve the thermal efficiency of the boiler; low temperature recycle of CO from flue gas2Concentration ofHigher than the gas phase, CO2The tri-atomic gas is beneficial to increasing the radiation heat transfer in the hearth 6 and is beneficial to stable combustion of the boiler while controlling the content of NOx. In conclusion, the low-temperature flue gas recirculation system and the method for low NOx of the pi-shaped boiler under low load can control the temperature and the oxygen content of the primary air in the coal mill 4 by adjusting the mixing ratio of the cold primary air, the hot primary air and the low-temperature recirculated flue gas, can effectively solve the contradiction between stable combustion of the boiler and control of the NOx content when the boiler operates under low load, and achieve the purpose of high-efficiency and clean operation of the pi-shaped boiler of the power station.
Drawings
FIG. 1 is a schematic structural diagram of a low-NOx low-temperature flue gas recirculation system of a pi-type boiler under low load.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by a person of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "top", "bottom", "one side", "the other side", "front", "back", "middle part", "inside", "top", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention; the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; furthermore, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, as they may be fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The present invention will be described in further detail with reference to the accompanying drawings.
As shown in FIG. 1, the invention provides a low-temperature flue gas recirculation system with low NOx of a pi-type boiler under low load, which comprises: the system comprises a primary fan 1, a low-temperature recirculation fan 2, a coal hopper 3, a coal mill 4, a combustor 5, a hearth 6, an over-fire air nozzle 7, a platen superheater 8, a superheater 9, a reheater 10, an economizer 11, an SCR catalyst layer 12, an air preheater 13, a temperature sensor 14, a gas mixing chamber 15, an oxygen meter 16, a primary hot air pipe 17, a primary cold air pipe 18, a low-temperature recirculation flue gas pipe 19, a low-temperature flue gas valve 20, a primary cold air valve 21, a primary hot air valve 22, an electric dust remover 23, an induced draft fan 24, a desulfurizing tower 25 and a chimney 26.
The overfire air nozzle 7 is positioned on the upper portion of the burner 5, the burner 5 and the overfire air nozzle 7 are symmetrically distributed on four corners of a hearth 6, the coal falling hopper 3 is arranged above the coal pulverizer 4 and is connected with the burner 5 through a coal falling pipe, the coal pulverizer 4 is connected with the burner 5 through a pulverized coal pipe, the temperature sensor 14 is positioned on an inlet hot air pipe of the coal pulverizer 4 and is carried by cold and hot primary air and low-temperature recycling flue gas, pulverized coal in the coal pulverizer 4 enters the burner 5 through the pulverized coal pipe, the pulverized coal carried by the primary air is combusted in the hearth 6, and the primary air temperature at the inlet of the coal pulverizer 4 is measured by the temperature sensor 14.
The screen superheater 8, the superheater 9 and the reheater 10 are sequentially arranged in a horizontal flue on the upper portion of the hearth 6, the economizer 11, the SCR catalyst layer 12 and the air preheater 13 are sequentially arranged in a vertical flue on the right side of the hearth 6, the screen superheater 8, the superheater 9, the reheater 10, the economizer 11 and the air preheater 13 all play a heat exchange role, the temperature of flue gas is reduced, and the SCR catalyst layer 12 reduces the concentration of NOx contained in the flue gas through the action of a catalyst.
The inlet of the electric dust collector 23 is connected with the outlet of the air preheater 13 through a pipeline and an induced draft fan 24, and the induced draft fan 24, the desulfurizing tower 25 and the chimney 26 are all connected with each other through pipelines in sequence.
The gas mixing chamber 15 is respectively connected with a cold primary air pipe 18, a low-temperature recycling flue gas pipe 19, a coal mill 4 and a hot primary air pipe 17, and the oxygen meter 16 is positioned on an inlet hot air pipe of the coal mill 4; the low-temperature recirculation fan 2 extracts low-temperature recirculation smoke through a pipeline, and a pipeline inlet is connected to an outlet flue of the electric dust collector 23.
The amount of wind once of cold that lets in coal pulverizer 4 is adjusted to wind valve 21 once of cold, the amount of wind once of heat that lets in coal pulverizer 4 is adjusted to wind valve 22 once of heat, low temperature recirculation fan 2 with low temperature flue gas valve 20 is adjusted and is let in the recirculated flue gas volume of coal pulverizer 4, under the boiler load of difference, through wind valve 21 once of cold, wind valve 22 once of heat and low temperature flue gas valve 20 are adjusted and are got into the volume proportion of the wind once of cold, wind once of heat and the low temperature recirculated flue gas volume of coal pulverizer 4, and then adjust the primary air temperature oxygen content of combustor 5 entry.
The invention also provides a low-temperature flue gas recirculation method of low NOx of the pi-type boiler under low load, which is characterized in that a part of flue gas is extracted from the side surface of an inlet flue of an economizer 11 through a low-temperature recirculation fan 2 to be used as low-temperature recirculation flue gas to be mixed with cold air and hot air in a cold primary air pipe 18 and a hot primary air pipe 17, and then mixed gas is introduced into a coal mill 4 and carries coal powder to enter a combustor 5; the cold primary air quantity is adjusted through the cold primary air valve 21, the hot primary air quantity is adjusted through the hot primary air valve 22, and the low-temperature flue gas air quantity is adjusted through the low-temperature flue gas valve 20 to adjust the temperature and the oxygen quantity of mixed gas at the inlet of the combustor 5.
Further, under the standard condition, when the load of the boiler is 30%, the volume ratio of the mixture of the low-temperature recirculated flue gas, the cold primary air and the hot primary air is 20% -30% of the low-temperature recirculated flue gas, 0% of the cold primary air and 70% -80% of the hot primary air; when the load of the boiler is 40%, the volume ratio of the mixture of the low-temperature recirculated flue gas, the cold primary air and the hot primary air is 20% -30% of the low-temperature recirculated flue gas, 0% -5% of the cold primary air and 70% -80% of the hot primary air.
Further, low temperature flue gas not drawn by the low temperature recirculation fan 2 is discharged from the stack 26 through the boiler flue.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims (7)

1. Low temperature flue gas recirculation system of low NOx under pi type boiler low-load includes: the device comprises a primary fan (1), a low-temperature recycling fan (2), a coal dropping hopper (3), a coal mill (4), a combustor (5), a hearth (6), an over-fire air nozzle (7), a platen superheater (8), a superheater (9), a reheater (10), an economizer (11), an SCR catalyst layer (12), an air preheater (13), temperature sensors (14), a gas mixing chamber (15), an oxygen meter (16), a primary hot air pipe (17), a primary cold air pipe (18), a low-temperature recycling flue gas pipe (19), a low-temperature flue gas valve (20), a primary cold air valve (21) and a primary hot air valve (22), wherein the combustors (5) are symmetrically distributed on the side wall of the hearth (6), the coal dropping hopper (3) is arranged above the coal mill (4) and connected through a pipeline, the coal mill (4) is connected with the combustor (5) through a coal dust pipe, and the temperature sensors (14) are positioned on an inlet hot air pipe of the coal mill (4), screen type over heater (8), over heater (9), re-heater (10) arrange in proper order in the horizontal flue on furnace (6) upper portion, economizer (11), SCR catalyst layer (12), air heater (13) arrange in proper order in the vertical flue on furnace (6) right side, gas mixing chamber (15) link to each other with cold primary air pipe (18), low temperature recirculation flue gas pipe (19), coal pulverizer (4), hot primary air pipe (17) respectively, electrostatic precipitator (23) entry is passed through the pipeline and is exported with air heater (13) and pass through pipeline and draught fan (24) and link to each other, and draught fan (24), desulfurizing tower (25), chimney (26) all loop through pipeline interconnect.
2. The low-temperature flue gas recirculation system with low NOx load of a pi-type boiler as claimed in claim 1, characterized in that the low-temperature recirculation fan (2) draws low-temperature recirculation flue gas through a low-temperature recirculation flue gas pipe (19), and a pipe inlet is connected to an outlet flue of the electric dust collector (23).
3. The low-temperature flue gas recirculation system with low NOx load of the pi-type boiler as claimed in claim 1, wherein the temperature sensor (14) is located on an inlet hot blast pipe of the coal mill (4).
4. The pi-type boiler low-load low-NOx low-temperature flue gas recirculation system according to claim 1, characterized in that the oxygen meter (16) is located on an inlet hot blast pipe of a coal mill (4).
5. The low-temperature flue gas recirculation method of low NOx under the low load of the pi-type boiler is characterized in that a part of flue gas is extracted from the side surface of an inlet flue of an economizer (11) through a low-temperature recirculation fan (2) to be used as low-temperature recirculation flue gas, the low-temperature recirculation flue gas is mixed with cold air and hot air in a cold primary air pipe (18) and a hot primary air pipe (17), and then mixed gas is introduced into a coal mill 4 and carries pulverized coal to enter a combustor (5); the cold primary air quantity is adjusted through the cold primary air valve (21), the hot primary air quantity is adjusted through the hot primary air valve (22), and the low-temperature flue gas quantity is adjusted through the low-temperature flue gas valve (20) so as to adjust the temperature and the oxygen quantity of mixed gas at the inlet of the combustor (5).
6. The pi-type boiler low-load low-NOx low-temperature flue gas recirculation method according to claim 5, wherein under a standard condition, when the load of the boiler is 30%, the volume ratio of the mixture of the low-temperature recirculated flue gas, the cold primary air and the hot primary air is 20% -30% of the low-temperature recirculated flue gas, the cold primary air is 0%, and the hot primary air is 70% -80%; when the load of the boiler is 40%, the volume ratio of the mixture of the low-temperature recirculated flue gas, the cold primary air and the hot primary air is 20% -30% of the low-temperature recirculated flue gas, 0% -5% of the cold primary air and 70% -80% of the hot primary air.
7. The low-temperature flue gas recirculation method with low NOx of pi-type boiler under low load according to claim 5, characterized in that the low-temperature flue gas which is not extracted by the low-temperature recirculation fan (2) is discharged from the chimney (26) through the boiler flue.
CN201911094770.6A 2019-11-11 2019-11-11 Low NO of pi-shaped boiler under low loadXLow temperature flue gas recirculation system and method Pending CN110822418A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111561694A (en) * 2020-06-03 2020-08-21 国网浙江省电力有限公司电力科学研究院 Method and system for improving low-load SCR inlet smoke temperature of coal-fired boiler
CN112870936A (en) * 2020-12-25 2021-06-01 国家能源集团福建能源有限责任公司 Denitration system of circulating fluidized bed boiler
CN114909647A (en) * 2022-05-07 2022-08-16 西安交通大学 Cogeneration unit and method for low-load stable combustion and thermoelectric deep decoupling

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111561694A (en) * 2020-06-03 2020-08-21 国网浙江省电力有限公司电力科学研究院 Method and system for improving low-load SCR inlet smoke temperature of coal-fired boiler
CN111561694B (en) * 2020-06-03 2022-01-25 国网浙江省电力有限公司电力科学研究院 Method and system for improving low-load SCR inlet smoke temperature of coal-fired boiler
CN112870936A (en) * 2020-12-25 2021-06-01 国家能源集团福建能源有限责任公司 Denitration system of circulating fluidized bed boiler
CN114909647A (en) * 2022-05-07 2022-08-16 西安交通大学 Cogeneration unit and method for low-load stable combustion and thermoelectric deep decoupling

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