CN109433011B - Method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristic - Google Patents
Method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristic Download PDFInfo
- Publication number
- CN109433011B CN109433011B CN201811264533.5A CN201811264533A CN109433011B CN 109433011 B CN109433011 B CN 109433011B CN 201811264533 A CN201811264533 A CN 201811264533A CN 109433011 B CN109433011 B CN 109433011B
- Authority
- CN
- China
- Prior art keywords
- temperature
- catalyst
- scr denitration
- ammonium bisulfate
- continuous
- 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.)
- Active
Links
Images
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
- B01D53/86—Catalytic processes
- B01D53/8621—Removing nitrogen compounds
- B01D53/8625—Nitrogen oxides
-
- 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
- B01D53/96—Regeneration, reactivation or recycling of reactants
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
Abstract
The invention relates to a method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics, which comprises the following steps: determining the lowest continuous ammonia spraying temperature of the catalyst, enabling the catalyst to continuously operate at a temperature T1, enabling the temperature T1 to be lower than the lowest continuous ammonia spraying temperature, enabling the continuous operation time to be T1, enabling the unit load corresponding to the temperature T1 to be W1, enabling the operation temperature of the catalyst to be increased to the temperature T2 for continuous operation after the continuous operation time of the catalyst at the temperature T1 exceeds T1, enabling the temperature T2 to be not lower than the lowest continuous ammonia spraying temperature, enabling the continuous operation time to be T2, enabling the unit load corresponding to the temperature T2 to be W2, and enabling the difference between the temperature W1 and the temperature W2 to be the percentage or potential which can be widened in low-load operation of SCR denitration of the unit. According to the invention, the field equipment temperature raising transformation is not needed, the wide-load operation of the denitration system is realized by fully utilizing the low-load adaptability of the catalyst, the transformation investment is reduced, the influence of machine halt on the power generation of the machine set is avoided, and the risk of influencing the normal operation of the machine set due to the equipment transformation is reduced.
Description
Technical Field
The invention relates to a method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics.
Background
Aiming at the current strict environmental protection emission standard, the flue gas SCR denitration technology is generally applied to coal-fired power plants. SCR denitration is achieved by using a reducing agent (such as NH)3Urea) under the action of catalyst selectively reacting with NOxReaction to form N2And H2O。
The flue gas of the coal-fired power plant contains SO3Gas, due to the nano-size of the catalyst itselfThe microporous structure of the stage is easy to generate capillary condensation phenomenon, and SO in the flue gas exists when the temperature of the flue gas is lower than the minimum continuous ammonia injection temperature (MOT) of the catalyst3、H2O will react with a reducing agent NH3And the ammonium bisulfate can block the microporous structure of the catalyst to cause the risk of poisoning.
In order to realize the emission reduction of nitrogen oxides under lower load of a unit, most coal-fired power plants adopt schemes of flue gas temperature regulation bypass modification, water bypass modification, heating surface grading modification and the like, so that the inlet flue gas temperature of a flue gas denitration system under low load is increased to be higher than the minimum continuous ammonia injection temperature (MOT), but the schemes of equipment modification have the risks of large investment and equipment failure caused by unit shutdown to influence power generation and operation.
Disclosure of Invention
The invention aims to provide a method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics, which is based on that after ammonium bisulfate is poisoned when a catalyst operates below the lowest continuous ammonia spraying temperature, the load of a unit is increased to cause the smoke temperature to be increased so that ammonium bisulfate in micropores of the catalyst is gasified and the performance of the catalyst is recovered.
In order to achieve the purpose, the invention adopts the technical scheme that:
a method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics comprises the following steps:
(1) determining the lowest continuous ammonia spraying temperature (MOT) of the catalyst,
(2) continuously operating the catalyst at a temperature of T1, wherein T1 is lower than the minimum continuous ammonia injection temperature (MOT), the continuous operation time is T1, the unit load corresponding to T1 is W1,
(3) after the continuous operation time of the catalyst at the temperature of T1 exceeds T1, the operation temperature of the catalyst is increased to T2 for continuous operation, the T2 is not lower than the minimum continuous ammonia injection temperature (MOT), the continuous operation time is T2, the unit load corresponding to T2 is W2,
(4) the difference values of W1 and W2 are the percentage or potential which can be widened in SCR denitration low-load operation of the unit.
Preferably, the minimum continuous ammonia injection temperature (MOT) of the catalyst used in the coal-fired power plant is 280-330 ℃, which is the minimum flue gas temperature at which the catalyst activity does not decrease with the operating time.
Preferably, in (2): t1 is 15-40 ℃ below the minimum continuous ammonia injection temperature (MOT), which is the lowest temperature at which catalyst activity decreases slightly with time but can be fully restored by raising the flue gas temperature.
Preferably, in (3): t2 is 0-30 deg.C above the minimum continuous ammonia injection temperature (MOT), which is the lowest temperature at which the activity of the catalyst, slightly poisoned by ammonium bisulfate, is fully restored.
Preferably, in (2): t1 is not less than 4 hours.
Preferably, in (3): t2 is not less than t 1.
Preferably, in (2): the SCR denitration operation load W1 of the unit is 0-40%.
Preferably, in (3): the SCR denitration operation load W2 of the unit is 20-60%, and W2 is not less than W1.
The mechanism of the present application is introduced: the poisoning of the ammonium bisulfate catalyst is physical poisoning, wherein the poisoning mechanism is that the capillary condensation effect of the catalyst at low temperature leads the ammonium bisulfate to block the microporous structure of the catalyst, so that the activity of the catalyst is reduced, the temperature is increased to recover the activity of the catalyst, and the ammonium bisulfate is gasified and released from the micropores of the catalyst by utilizing the increased temperature, so that the activity of the catalyst is recovered.
Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages and effects:
according to the invention, the field equipment temperature raising transformation is not needed, the wide-load operation of the denitration system is realized by fully utilizing the low-load adaptability of the catalyst, the transformation investment is reduced, the influence of machine halt on the power generation of the machine set is avoided, and the risk of influencing the normal operation of the machine set due to the equipment transformation is reduced.
Drawings
FIG. 1 is a graph of broadening SCR denitration commissioning load based on catalyst ammonium bisulfate poisoning recovery characteristics.
Wherein: the upper curve is the change of the unit load with timeA curve; the middle curve is a curve of the denitration inlet smoke temperature changing along with the load of the set; the lower curve is the catalyst activity K/K0Time profile.
Detailed Description
The invention is further described below with reference to the accompanying drawings and embodiments:
the first embodiment is as follows:
a certain 300MW coal-fired unit: SO in inlet flue gas of SCR denitration system3Concentration 10.0. mu.L/L, H2O content 9.0%, NOx concentration 500mg/m3(dry basis, standard, 6.0% O2) And the NOx emission concentration at the outlet of the denitration system is 50mg/m3(dry basis, standard, 6.0% O2）。
A method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics comprises the following steps:
(1) determining the lowest continuous ammonia spraying temperature (MOT) of the catalyst to be 308 ℃,
(2) continuously operating the catalyst at the temperature T1 of 283 ℃, namely, the T1 is lower than the minimum continuous ammonia injection temperature (MOT) of 25 ℃, and the continuous operation time T1 is 5 hours, obtaining the unit load W1 corresponding to the T1 of 38 percent,
(3) after the continuous operation time of the catalyst at 283 ℃ exceeds 5 hours, the operation temperature of the catalyst is increased to T2 and 310 ℃ for continuous operation, T2 is higher than the minimum continuous ammonia injection temperature (MOT), the temperature rise performance of the catalyst is completely recovered, the continuous operation time T2 is 10 hours, the load of a unit corresponding to T2 is 60 percent of W2,
(4) and calculating the difference W2-W1=60% -38% =22% of W1 and W2, wherein the difference 22% is the percentage or potential which can be widened in SCR denitration low-load operation of the unit.
Example two:
a certain 600MW coal-fired unit: SO in inlet flue gas of SCR denitration system3Concentration 7.0. mu.L/L, H2O content 8.5%, NOx concentration 300mg/m3(dry basis, standard, 6.0% O2) NOx emission concentration at outlet of denitration system is 50mg/m3 (dry basis, standard state, 6.0% O)2）。
A method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics comprises the following steps:
(1) determining the lowest continuous ammonia spraying temperature (MOT) of the catalyst to be 305 ℃,
(2) continuously operating the catalyst at the temperature T1 of 280 ℃, namely, the T1 is lower than the lowest continuous ammonia spraying temperature (MOT) of 25 ℃, and the continuous operation time T1 is 6h, obtaining the unit load W1 corresponding to the T1 of 40 percent,
(3) after the continuous operation time of the catalyst at 280 ℃ exceeds 6h, the operation temperature of the catalyst is increased to T2 and 305 ℃ for continuous operation, T2 is equal to the lowest continuous ammonia injection temperature (MOT), the temperature rise performance of the catalyst is completely recovered, the continuous operation time T2 is 8h, the load of a unit corresponding to T2 is 50% of W2,
(4) and calculating the difference W2-W1=50% -40% =10% of W1 and W2, wherein the difference 10% is the percentage or potential which can be widened in SCR denitration low-load operation of the unit.
Example three:
a 1000MW coal-fired unit: SO in inlet flue gas of SCR denitration system3Concentration 5.0. mu.L/L, H2O content 8.0%, NOx concentration 200mg/m3(dry basis, standard, 6.0% O2) And the NOx emission concentration at the outlet of the denitration system is 50mg/m3(dry basis, standard, 6.0% O2）。
A method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics comprises the following steps:
(1) determining the lowest continuous ammonia spraying temperature (MOT) of the catalyst to be 298 ℃,
(2) continuously operating the catalyst at the temperature T1 of 275 ℃, namely, the T1 is lower than the lowest continuous ammonia spraying temperature (MOT) of 23 ℃, and the continuous operation time T1 is 8h, obtaining the unit load W1 corresponding to the T1 of 0 percent,
(3) after the continuous operation time of the catalyst at 275 ℃ exceeds 8h, the operation temperature of the catalyst is increased to T2 and 298 ℃ for continuous operation, T2 is equal to the lowest continuous ammonia injection temperature (MOT), the temperature rise performance of the catalyst is completely recovered, the continuous operation time T2 is 8h, the load of a unit corresponding to T2 is obtained, W2 is 40%,
(4) and calculating the difference W2-W1=40% -0% =40% of W1 and W2, wherein the difference 40% is the percentage or potential which can be widened in SCR denitration low-load operation of the unit.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.
Claims (7)
1. A method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics is characterized by comprising the following steps of: the method comprises the following steps:
(1) determining the lowest continuous ammonia spraying temperature (MOT) of the catalyst,
(2) the catalyst is continuously operated at the temperature of T1, the temperature of T1 is 15-40 ℃ lower than the minimum continuous ammonia spraying temperature (MOT), the temperature is the minimum temperature at which the activity of the catalyst is slightly reduced along with the operation time, but the activity of the catalyst can be completely recovered by increasing the temperature of flue gas, the continuous operation time is T1, the unit load corresponding to T1 is W1,
(3) after the continuous operation time of the catalyst at the temperature of T1 exceeds T1, the operation temperature of the catalyst is increased to T2 for continuous operation, the temperature of T2 is 0-30 ℃ higher than the minimum continuous ammonia injection temperature (MOT), the temperature is the minimum temperature which can completely recover the activity of the catalyst slightly poisoned by ammonium bisulfate, the continuous operation time is T2, T2 is the time for completely recovering the temperature rising performance of the catalyst at the temperature of T2, the unit load corresponding to T2 is W2,
(4) the difference values of W1 and W2 are the percentage or potential which can be widened in SCR denitration low-load operation of the unit.
2. The method for broadening SCR denitration low load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics as defined in claim 1 wherein: the minimum continuous ammonia injection temperature (MOT) of the catalyst used in the coal-fired power plant is 280-330 ℃.
3. The method for broadening SCR denitration low load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics as defined in claim 1 or 2 wherein: in (3): t2 is above the minimum continuous ammonia injection temperature (MOT).
4. The method for broadening SCR denitration low load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics as defined in claim 1 wherein: in (2): t1 is not less than 4 hours.
5. The method for broadening SCR denitration low load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics as defined in claim 1 or 4 wherein: in (3): t2 is not less than t 1.
6. The method for broadening SCR denitration low load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics as defined in claim 1 wherein: in (2): the SCR denitration operation load W1 of the unit is 0-40%.
7. The method for broadening SCR denitration low load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristics as defined in claim 1 wherein: in (3): the SCR denitration operation load W2 of the unit is 20-60%, and W2 is not less than W1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811264533.5A CN109433011B (en) | 2018-10-29 | 2018-10-29 | Method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristic |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811264533.5A CN109433011B (en) | 2018-10-29 | 2018-10-29 | Method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristic |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109433011A CN109433011A (en) | 2019-03-08 |
| CN109433011B true CN109433011B (en) | 2022-03-29 |
Family
ID=65548731
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811264533.5A Active CN109433011B (en) | 2018-10-29 | 2018-10-29 | Method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristic |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109433011B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111389219B (en) * | 2020-03-27 | 2021-11-02 | 浙江浙能技术研究院有限公司 | Ammonia injection control method for start-stop stage of coal-fired boiler |
| CN112717690B (en) * | 2020-11-10 | 2023-02-21 | 苏州西热节能环保技术有限公司 | SCR denitration commissioning method under deep peak regulation working condition of coal-fired unit |
| CN114832867B (en) * | 2021-02-02 | 2023-09-29 | 国家能源投资集团有限责任公司 | Start-up method for improving low-temperature activity of honeycomb denitration catalyst |
| CN117379951B (en) * | 2023-12-11 | 2024-04-05 | 苏州西热节能环保技术有限公司 | Full-load wide-temperature running method of SCR flue gas denitration catalyst of coal-fired unit |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107376635A (en) * | 2016-08-18 | 2017-11-24 | 天津大唐国际盘山发电有限责任公司 | A kind of anti-cold operation automatic protecting method of catalyst for denitrating flue gas and control system |
-
2018
- 2018-10-29 CN CN201811264533.5A patent/CN109433011B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107376635A (en) * | 2016-08-18 | 2017-11-24 | 天津大唐国际盘山发电有限责任公司 | A kind of anti-cold operation automatic protecting method of catalyst for denitrating flue gas and control system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109433011A (en) | 2019-03-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109433011B (en) | Method for widening SCR denitration low-load operation potential based on catalyst ammonium bisulfate poisoning recovery characteristic | |
| CN103463978B (en) | Based on the device and method of catalytic oxidation of hydrogen peroxide flue gas and desulfurizing and denitrifying | |
| CN105327612A (en) | Flue gas low-temperature combined desulfurization and denitration technology method | |
| CN104437540A (en) | Phosphorus-resistant low-temperature SCR denitration catalyst and preparation method thereof | |
| CN104525216A (en) | Denitration catalyst for wide temperature window under high sulfur condition and preparation method thereof | |
| CN106853327B (en) | Low-temperature flue gas desulfurization and denitrification integrated method and device | |
| CN102233239A (en) | System and method for controlling and reducing NOx emissions | |
| CN105688936A (en) | In-situ regeneration method of ammonium sulfate poisoning denitration catalyst | |
| CN105536886A (en) | Regeneration method of arsenic poisoning denitration catalyst | |
| CN108993476B (en) | Metal oxide-vanadate/TiO2Catalyst, preparation method and application thereof | |
| CN102872858B (en) | Denitration catalyst with sulfur oxidation preventive characteristic and preparation method thereof | |
| CN108568210B (en) | Smoke reheating white smoke eliminating process and method for cooperating with CO low-temperature denitration | |
| CN103433081B (en) | Regeneration method for honeycomb type SCR (Selective Catalytic Reduction) denitration catalyst | |
| CN111097442A (en) | Flue gas synergistic denitration and demercuration catalyst and preparation method thereof | |
| CN102764657A (en) | Nano V205/activated coke denitration catalyst and preparation method of catalyst | |
| CN108671931A (en) | A kind of method of modifying of the denitrating catalyst with anti-toxicity energy | |
| CN105642339B (en) | Desulphurization denitration catalyst and preparation method while one kind is without also Primordial Qi | |
| CN113750783A (en) | Method of two-section type SCR reaction device suitable for wide-temperature-zone denitration | |
| CN206463781U (en) | A kind of desulfuring and denitrifying apparatus of coke oven flue gas | |
| CN108579731A (en) | A kind of preparation method of low-temperature denitration carbon-supported catalysts | |
| CN206897181U (en) | A kind of low-temperature SCR denitrating flue gas reaction unit | |
| CN112169808A (en) | Desulfurization and denitrification catalyst and preparation method thereof | |
| CN103007707B (en) | Combined SNCR-SCR system used for industrial boiler and having high load adaptability, and SNCR-SCR combination method thereof | |
| CN103341306B (en) | A kind of method of poor ammonia SNCR reduction and oxidative absorption combined denitration demercuration | |
| JP6667867B2 (en) | Boiler equipment and its operation method |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |