CN113368681A - Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler - Google Patents

Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler Download PDF

Info

Publication number
CN113368681A
CN113368681A CN202110669692.9A CN202110669692A CN113368681A CN 113368681 A CN113368681 A CN 113368681A CN 202110669692 A CN202110669692 A CN 202110669692A CN 113368681 A CN113368681 A CN 113368681A
Authority
CN
China
Prior art keywords
flue gas
urea solution
nitrogen oxide
outlet flue
nitrogen oxides
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202110669692.9A
Other languages
Chinese (zh)
Inventor
潘晓波
许凌云
刘维纲
张辰龙
孔庆龙
贾龙
徐甲佳
李楠
李显江
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huaneng Taiyuan Dongshan Gas Turbine Thermal Power Co Ltd
Original Assignee
Huaneng Taiyuan Dongshan Gas Turbine Thermal Power Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huaneng Taiyuan Dongshan Gas Turbine Thermal Power Co Ltd filed Critical Huaneng Taiyuan Dongshan Gas Turbine Thermal Power Co Ltd
Priority to CN202110669692.9A priority Critical patent/CN113368681A/en
Publication of CN113368681A publication Critical patent/CN113368681A/en
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/77—Liquid phase processes
    • B01D53/78—Liquid phase processes with gas-liquid contact
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/346—Controlling the process
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/54—Nitrogen compounds
    • B01D53/56—Nitrogen oxides
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
    • F22B1/18—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
    • G06F17/10—Complex mathematical operations
    • G06F17/18—Complex mathematical operations for evaluating statistical data, e.g. average values, frequency distributions, probability functions, regression analysis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/20—Reductants
    • B01D2251/206—Ammonium compounds
    • B01D2251/2067—Urea
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2258/00—Sources of waste gases
    • B01D2258/02—Other waste gases
    • B01D2258/0283—Flue gases

Abstract

The invention relates to a flue gas nitrogen oxide control technology, in particular to a flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler. The invention solves the problems of poor control accuracy and slow control response speed of the existing flue gas nitrogen oxide control method. A flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler is realized by adopting the following steps: the method comprises the following steps: setting a target value of the content of nitrogen oxides in outlet flue gas of a combined cycle unit waste heat boilerQ 1(ii) a Step two: calculating the target value of the discharge amount of nitrogen oxidesM 1(ii) a Step three: calculating the actual value of the emission of nitrogen oxidesM 2(ii) a Step four: calculating the required increased urea quantity deltaM(ii) a Step five: calculating the required increased supply quantity delta of the urea solutiont(ii) a Step six: calculating the supply amount of urea solutiont(ii) a Step seven: the required supply quantity delta of the urea solution is increasedtAs a feed forward for the PID controller. The invention is suitable for the combined cycle unit waste heat boiler.

Description

Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler
Technical Field
The invention relates to a flue gas nitrogen oxide control technology, in particular to a flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler.
Background
With the stricter and stricter international and domestic requirements on the emission indexes of power plants, the power plants are required to further reduce the content of nitrogen oxides in the outlet flue gas of the combined cycle unit waste heat boiler. Under the condition of the prior art, in order to reduce the content of nitrogen oxides in the outlet flue gas of the combined cycle unit waste heat boiler, the adopted control method is to directly use the deviation of the actual value and the target value of the content of the nitrogen oxides as the feedforward of a PID controller, and then the PID controller is used for regulating the supply amount of the urea solution. Due to the self principle, the control method has blindness and hysteresis in the control process, thereby resulting in poor control accuracy and slow control response speed. Based on the above, a flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler is needed to be invented, so as to solve the problems of poor control accuracy and slow control response speed of the existing flue gas nitrogen oxide control method.
Disclosure of Invention
The invention provides a flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler, aiming at solving the problems of poor control accuracy and slow control response speed of the existing flue gas nitrogen oxide control method.
The invention is realized by adopting the following technical scheme:
a flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler is realized by adopting the following steps:
the method comprises the following steps: setting a target value of the content of nitrogen oxides in outlet flue gas of a combined cycle unit waste heat boilerQ 1(ii) a The following operating parameters of the combined cycle unit waste heat boiler are collected: outlet flue gas flowfActual value of nitrogen oxide content in outlet flue gasQ 2Current urea solution supplyt 0；
Step two: according to the outlet flue gas flowfAnd target value of nitrogen oxide content in outlet flue gasQ 1Calculating the target value of the discharge amount of nitrogen oxidesM 1(ii) a The specific calculation formula is as follows:
M 1=f×Q 1；
step three: according to the outlet flue gas flowfAnd the actual value of the content of nitrogen oxides in the outlet flue gasQ 2Calculating the actual value of the emission of nitrogen oxidesM 2(ii) a The specific calculation formula is as follows:
M 2=f×Q 2；
step four: according to the target value of the emission amount of nitrogen oxidesM 1And the actual value of the emission of nitrogen oxidesM 2Calculating the required increased urea quantity deltaM(ii) a The specific calculation formula is as follows:
ΔM=（M 2- M 1）/1000/180×120/1000；
step five: according to the required increased urea quantity deltaMCalculating the required increased supply quantity delta of the urea solutiont(ii) a The specific calculation formula is as follows:
Δt=ΔM/N 1/N 2/q/p；
in the formula:N 1showing the efficiency of the pyrolysis furnace in decomposing ammonia gas;N 2the reaction efficiency of ammonia and nitrogen oxides is shown;qrepresenting the mass concentration of the urea solution;prepresents the urea solution density at the current temperature;N 1、N 2、q、pare all known amounts;
step six: according to the current supply amount of urea solutiont 0And the required increased supply of urea solution ΔtCalculating the supply amount of urea solutiont(ii) a The specific calculation formula is as follows:
t=t 0+Δt；
step seven: the required supply quantity delta of the urea solution is increasedtAs a feed forward of the PID controller, the opening degree of the urea solution supply regulating valve is then regulated by the PID controller, thereby allowing the urea solution supply amount to be controlled by the control unitt 0Rise totSo as to make the actual value of the content of the nitrogen oxide in the outlet flue gasQ 2And the target value of the content of nitrogen oxide in the outlet flue gasQ 1Are equal.
Compared with the existing flue gas nitrogen oxide control method, the flue gas nitrogen oxide control method for the combined cycle unit waste heat boiler does not directly use the deviation of the actual value and the target value of the nitrogen oxide content as the feedforward of the PID controller, but firstly calculates the required urea solution supply amount, and then uses the required urea solution supply amount as the feedforward of the PID controller, thereby effectively eliminating the blindness and the hysteresis in the control process and further effectively improving the control accuracy and the control response speed.
The method effectively solves the problems of poor control accuracy and slow control response speed of the existing flue gas nitrogen oxide control method, and is suitable for the combined cycle unit waste heat boiler.
Detailed Description
A flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler is realized by adopting the following steps:
the method comprises the following steps: setting a target value of the content of nitrogen oxides in outlet flue gas of a combined cycle unit waste heat boilerQ 1(ii) a The following operating parameters of the combined cycle unit waste heat boiler are collected: outlet flue gas flowfActual value of nitrogen oxide content in outlet flue gasQ 2Current urea solution supplyt 0；
Step two: according to the outlet flue gas flowfAnd target value of nitrogen oxide content in outlet flue gasQ 1Calculating the target value of the discharge amount of nitrogen oxidesM 1(ii) a The specific calculation formula is as follows:
M 1=f×Q 1；
step three: according to the outlet flue gas flowfAnd the actual value of the content of nitrogen oxides in the outlet flue gasQ 2Calculating the actual value of the emission of nitrogen oxidesM 2(ii) a The specific calculation formula is as follows:
M 2=f×Q 2；
step four: according to the target value of the emission amount of nitrogen oxidesM 1And the actual value of the emission of nitrogen oxidesM 2Calculating the required increased urea quantity deltaM(ii) a The specific calculation formula is as follows:
ΔM=（M 2- M 1）/1000/180×120/1000；
step five: according to the required increased urea quantity deltaMCalculating the required increased supply quantity delta of the urea solutiont(ii) a The specific calculation formula is as follows:
Δt=ΔM/N 1/N 2/q/p；
in the formula:N 1showing the efficiency of the pyrolysis furnace in decomposing ammonia gas;N 2the reaction efficiency of ammonia and nitrogen oxides is shown;qrepresenting the mass concentration of the urea solution;prepresents the urea solution density at the current temperature;N 1、N 2、q、pare all known amounts;
step six:according to the current supply amount of urea solutiont 0And the required increased supply of urea solution ΔtCalculating the supply amount of urea solutiont(ii) a The specific calculation formula is as follows:
t=t 0+Δt；
step seven: the required supply quantity delta of the urea solution is increasedtAs a feed forward of the PID controller, the opening degree of the urea solution supply regulating valve is then regulated by the PID controller, thereby allowing the urea solution supply amount to be controlled by the control unitt 0Rise totSo as to make the actual value of the content of the nitrogen oxide in the outlet flue gasQ 2And the target value of the content of nitrogen oxide in the outlet flue gasQ 1Are equal.
Target value of nitrogen oxide content in outlet flue gasQ 1In units of mg/m3(ii) a Actual value of nitrogen oxide content in outlet flue gasQ 2In units of mg/m3(ii) a Outlet flue gas flowfHas the unit of m3H; current urea solution supplyt 0Has the unit of m3H; the required increased supply quantity delta of urea solutiontHas the unit of m3H; the supply of urea solution to be achievedtHas the unit of m3H; target value of emission amount of nitrogen oxidesM 1The unit of (A) is mg/h; actual value of nitrogen oxide emissionM 2The unit of (A) is mg/h; the required increased amount of urea DeltaMThe unit of (b) is mg/h.
While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that these are by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.

Claims (2)

1. A flue gas nitrogen oxide control method for a combined cycle unit waste heat boiler is characterized by comprising the following steps: the method is realized by adopting the following steps:
the method comprises the following steps: setting a target value of the content of nitrogen oxides in outlet flue gas of a combined cycle unit waste heat boilerQ 1(ii) a The following operating parameters of the combined cycle unit waste heat boiler are collected: outlet flue gas flowfActual value of nitrogen oxide content in outlet flue gasQ 2Current urea solution supplyt 0；
Step two: according to the outlet flue gas flowfAnd target value of nitrogen oxide content in outlet flue gasQ 1Calculating the target value of the discharge amount of nitrogen oxidesM 1(ii) a The specific calculation formula is as follows:
M 1=f×Q 1；
step three: according to the outlet flue gas flowfAnd the actual value of the content of nitrogen oxides in the outlet flue gasQ 2Calculating the actual value of the emission of nitrogen oxidesM 2(ii) a The specific calculation formula is as follows:
M 2=f×Q 2；
step four: according to the target value of the emission amount of nitrogen oxidesM 1And the actual value of the emission of nitrogen oxidesM 2Calculating the required increased urea quantity deltaM(ii) a The specific calculation formula is as follows:
ΔM=（M 2- M 1）/1000/180×120/1000；
step five: according to the required increased urea quantity deltaMCalculating the required increased supply quantity delta of the urea solutiont(ii) a The specific calculation formula is as follows:
Δt=ΔM/N 1/N 2/q/p；
in the formula:N 1showing the efficiency of the pyrolysis furnace in decomposing ammonia gas;N 2the reaction efficiency of ammonia and nitrogen oxides is shown;qrepresenting the mass concentration of the urea solution;prepresents the urea solution density at the current temperature;N 1、N 2、q、pare all known amounts;
step six: according to the current supply amount of urea solutiont 0And the required increased supply of urea solution ΔtCalculating the supply amount of urea solutiont(ii) a The specific calculation formula is as follows:
t=t 0+Δt；
step seven: the required supply quantity delta of the urea solution is increasedtAs a feed forward of the PID controller, the opening degree of the urea solution supply regulating valve is then regulated by the PID controller, thereby allowing the urea solution supply amount to be controlled by the control unitt 0Rise totSo as to make the actual value of the content of the nitrogen oxide in the outlet flue gasQ 2And the target value of the content of nitrogen oxide in the outlet flue gasQ 1Are equal.
2. The method for controlling the nitrogen oxides in the flue gas of the waste heat boiler of the combined cycle unit according to the claim 1, is characterized in that: target value of nitrogen oxide content in outlet flue gasQ 1In units of mg/m3(ii) a Actual value of nitrogen oxide content in outlet flue gasQ 2In units of mg/m3(ii) a Outlet flue gas flowfHas the unit of m3H; current urea solution supplyt 0Has the unit of m3H; the required increased supply quantity delta of urea solutiontHas the unit of m3H; the supply of urea solution to be achievedtHas the unit of m3H; target value of emission amount of nitrogen oxidesM 1The unit of (A) is mg/h; actual value of nitrogen oxide emissionM 2The unit of (A) is mg/h; the required increased amount of urea DeltaMThe unit of (b) is mg/h.
CN202110669692.9A 2021-06-17 2021-06-17 Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler Pending CN113368681A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110669692.9A CN113368681A (en) 2021-06-17 2021-06-17 Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110669692.9A CN113368681A (en) 2021-06-17 2021-06-17 Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler

Publications (1)

Publication Number Publication Date
CN113368681A true CN113368681A (en) 2021-09-10

Family

ID=77577340

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110669692.9A Pending CN113368681A (en) 2021-06-17 2021-06-17 Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler

Country Status (1)

Country Link
CN (1) CN113368681A (en)

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03146116A (en) * 1989-10-31 1991-06-21 Hitachi Zosen Corp Simplified denitrification process
JPH08257370A (en) * 1995-03-27 1996-10-08 Hitachi Zosen Corp Exhaust gas denitration apparatus
JPH1033948A (en) * 1996-07-25 1998-02-10 Ngk Insulators Ltd Denitration system and denitration method
JP2003290630A (en) * 2002-04-03 2003-10-14 Mitsubishi Heavy Ind Ltd Treatment apparatus for nitrogen oxide and treatment method for nitrogen oxide
JP2010234321A (en) * 2009-03-31 2010-10-21 Chugoku Electric Power Co Inc:The Ammonia injection amount correction controller and ammonia injection amount correction control method
CN204193774U (en) * 2014-09-01 2015-03-11 南通市电站阀门有限公司 A kind of denitrating flue gas metering module
CN105487377A (en) * 2016-01-05 2016-04-13 江苏紫光吉地达环境科技有限公司 Fuzzy controller of denitrated urea pyrolysis process
CN207169430U (en) * 2017-09-14 2018-04-03 上海宝钢节能环保技术有限公司 Urea pyrolysis and spraying system for low-temperature smoke air SCR denitration
WO2019019046A1 (en) * 2017-07-26 2019-01-31 罗伯特·博世有限公司 Injection amount control method and device for scr urea injection system in engine
CN109343349A (en) * 2018-11-01 2019-02-15 大唐环境产业集团股份有限公司 A kind of SCR denitrating flue gas Optimal Control System and method based on ammonia spraying amount compensator
CN110824907A (en) * 2019-11-29 2020-02-21 陕西中节能环保科技有限公司 Boiler flue gas denitration control method based on self-adaptive fuzzy PID algorithm
CN112452128A (en) * 2020-11-09 2021-03-09 华能铜川照金煤电有限公司 Control method for automatically adjusting nitrogen oxide set value at outlet of variable denitration SCR (Selective catalytic reduction)
CN112870972A (en) * 2021-01-12 2021-06-01 中国能源建设集团华中电力试验研究院有限公司 Thermal power plant exhaust flue gas nitrogen oxide concentration control method and system

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03146116A (en) * 1989-10-31 1991-06-21 Hitachi Zosen Corp Simplified denitrification process
JPH08257370A (en) * 1995-03-27 1996-10-08 Hitachi Zosen Corp Exhaust gas denitration apparatus
JPH1033948A (en) * 1996-07-25 1998-02-10 Ngk Insulators Ltd Denitration system and denitration method
JP2003290630A (en) * 2002-04-03 2003-10-14 Mitsubishi Heavy Ind Ltd Treatment apparatus for nitrogen oxide and treatment method for nitrogen oxide
JP2010234321A (en) * 2009-03-31 2010-10-21 Chugoku Electric Power Co Inc:The Ammonia injection amount correction controller and ammonia injection amount correction control method
CN204193774U (en) * 2014-09-01 2015-03-11 南通市电站阀门有限公司 A kind of denitrating flue gas metering module
CN105487377A (en) * 2016-01-05 2016-04-13 江苏紫光吉地达环境科技有限公司 Fuzzy controller of denitrated urea pyrolysis process
WO2019019046A1 (en) * 2017-07-26 2019-01-31 罗伯特·博世有限公司 Injection amount control method and device for scr urea injection system in engine
CN207169430U (en) * 2017-09-14 2018-04-03 上海宝钢节能环保技术有限公司 Urea pyrolysis and spraying system for low-temperature smoke air SCR denitration
CN109343349A (en) * 2018-11-01 2019-02-15 大唐环境产业集团股份有限公司 A kind of SCR denitrating flue gas Optimal Control System and method based on ammonia spraying amount compensator
CN110824907A (en) * 2019-11-29 2020-02-21 陕西中节能环保科技有限公司 Boiler flue gas denitration control method based on self-adaptive fuzzy PID algorithm
CN112452128A (en) * 2020-11-09 2021-03-09 华能铜川照金煤电有限公司 Control method for automatically adjusting nitrogen oxide set value at outlet of variable denitration SCR (Selective catalytic reduction)
CN112870972A (en) * 2021-01-12 2021-06-01 中国能源建设集团华中电力试验研究院有限公司 Thermal power plant exhaust flue gas nitrogen oxide concentration control method and system

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
上海市环境保护工业行业协会编著: "《工业大气污染防治技术及应用》", 30 November 2016, 上海科学技术出版社 *
周长城等: "负荷随动烟气选择性催化还原脱硝控制策略优化研究及工程应用", 《环境污染与防治》 *
陈文敏等: "《洁净煤技术基础》", 30 September 1999, 煤炭工业出版社 *

Similar Documents

Publication Publication Date Title
CN107014217B (en) Coke oven gas utilization and flue gas treatment system of coking plant and treatment method thereof
CN109945223B (en) Full-working-condition auxiliary denitration system and operation method
CN101749730B (en) Coal burning heat medium furnace high-precision temperature regulation and combustion control method
CN107023825A (en) Fluidized-bed combustion boiler is controlled and combustion optimizing system
CN101881563B (en) Multi-area intelligent online optimizing control method for thermal efficiency of heating furnace
CN111637442A (en) Configuration self-adaptive efficient flexible clean coal-fired power generation system and operation method
CN112650052A (en) Thermal power generating unit SCR denitration control method for preventing failure of main regulation
CN105487377B (en) A kind of fuzzy controller of denitration urea pyrolysis technique
CN113419570A (en) Control method of flue gas denitration system of waste incineration power plant
CN113368681A (en) Flue gas nitrogen oxide control method for combined cycle unit waste heat boiler
CN112239797A (en) Large blast furnace top combustion type hot blast furnace vault temperature control technology
CN116499272B (en) Intelligent kiln control method for tracking multi-energy combustion carbon emission
CN113477045A (en) Base spraying removal SO3In the fine control method
CN110652845A (en) Feedforward control method for flue gas deacidification reaction tower of garbage incinerator
CN113019086B (en) Precise feeding method of desulfurization synergist
CN115025616A (en) Automatic control method for urea method SCR denitration technology of thermal power generating unit
Hu et al. Multiple model switching DMC-PID cascade predictive control for SCR denitration systems
CN202057204U (en) Waste gas desulfuration and dust control device of carbon calcining furnace
CN215742862U (en) Removal of SO3System for reducing lowest continuous ammonia spraying temperature of SCR denitration equipment
CN219624088U (en) Adjusting system for temperature of medium-temperature SCR denitration flue gas
CN215411911U (en) Energy-saving heat storage incineration device
CN116651203A (en) SCR denitration system control method suitable for frequent fluctuation of unit load
CN114857945B (en) High-temperature-resistant industrial boiler treatment process
CN103148502B (en) Method for alleviating corrosion of boiler preheater
CN109240380B (en) Control method of urea pyrolysis flue gas heat exchanger system

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20210910