CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use Methane
The need to reduce global carbon dioxide (CO<sub>2</sub>) emissions is driving the conversion of coal-fired power plants to use methane, which can reduce CO<sub>2</sub> emissions by >40%. However, conducting gas firing in coal boilers changes the heat transfer profile; the...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-12-01
|
| Series: | Energies |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1073/15/1/246 |
| _version_ | 1797499103555354624 |
|---|---|
| author | Kang-Min Kim Gyu-Bo Kim Byoung-Hwa Lee Yoon-Ho Bae Chung-Hwan Jeon |
| author_facet | Kang-Min Kim Gyu-Bo Kim Byoung-Hwa Lee Yoon-Ho Bae Chung-Hwan Jeon |
| author_sort | Kang-Min Kim |
| collection | DOAJ |
| description | The need to reduce global carbon dioxide (CO<sub>2</sub>) emissions is driving the conversion of coal-fired power plants to use methane, which can reduce CO<sub>2</sub> emissions by >40%. However, conducting gas firing in coal boilers changes the heat transfer profile; therefore, preliminary evaluations using computational fluid dynamics are required prior to conversion. Here, methane was used as a heat input source in the simulation of an existing coal boiler, and combustion, nitrogen oxides (NOx) emission characteristics, and heat transfer profile changes inside the boiler were analyzed. Furthermore, changes in the burner zone stoichiometric ratio (BZSR) were simulated to restore the decreased heat absorption of the furnace waterwall, revealing that air distribution could change the heat absorption of the waterwall and tube bundles. However, this change was smaller than that caused by conversion from coal to methane. Therefore, to implement gas firing in coal boilers, alternatives such as output derating, using an attemperator, or modifying heat transfer surfaces are necessary. Despite these limitations, a 70% reduction in NOx emissions was achieved at a BZSR of 0.76, compared with coal. As the BZSR contributes significantly to NOx emissions, conducting gas firing in existing coal boilers could significantly reduce NOx and CO<sub>2</sub> emissions. |
| first_indexed | 2024-03-10T03:42:40Z |
| format | Article |
| id | doaj.art-91786e419875483ab5fdee6bd8f54d5a |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T03:42:40Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-91786e419875483ab5fdee6bd8f54d5a2023-11-23T11:27:42ZengMDPI AGEnergies1996-10732021-12-0115124610.3390/en15010246CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use MethaneKang-Min Kim0Gyu-Bo Kim1Byoung-Hwa Lee2Yoon-Ho Bae3Chung-Hwan Jeon4School of Mechanical Engineering, Pusan National University, Busan 46241, KoreaPusan Clean Energy Research Institute, Pusan National University, Busan 46241, KoreaPusan Clean Energy Research Institute, Pusan National University, Busan 46241, KoreaSchool of Mechanical Engineering, Pusan National University, Busan 46241, KoreaSchool of Mechanical Engineering, Pusan National University, Busan 46241, KoreaThe need to reduce global carbon dioxide (CO<sub>2</sub>) emissions is driving the conversion of coal-fired power plants to use methane, which can reduce CO<sub>2</sub> emissions by >40%. However, conducting gas firing in coal boilers changes the heat transfer profile; therefore, preliminary evaluations using computational fluid dynamics are required prior to conversion. Here, methane was used as a heat input source in the simulation of an existing coal boiler, and combustion, nitrogen oxides (NOx) emission characteristics, and heat transfer profile changes inside the boiler were analyzed. Furthermore, changes in the burner zone stoichiometric ratio (BZSR) were simulated to restore the decreased heat absorption of the furnace waterwall, revealing that air distribution could change the heat absorption of the waterwall and tube bundles. However, this change was smaller than that caused by conversion from coal to methane. Therefore, to implement gas firing in coal boilers, alternatives such as output derating, using an attemperator, or modifying heat transfer surfaces are necessary. Despite these limitations, a 70% reduction in NOx emissions was achieved at a BZSR of 0.76, compared with coal. As the BZSR contributes significantly to NOx emissions, conducting gas firing in existing coal boilers could significantly reduce NOx and CO<sub>2</sub> emissions.https://www.mdpi.com/1996-1073/15/1/246computational fluid dynamicstangentially fired coal boilerconversion to methanenitrogen oxidesheat transferfurnace exit gas temperature |
| spellingShingle | Kang-Min Kim Gyu-Bo Kim Byoung-Hwa Lee Yoon-Ho Bae Chung-Hwan Jeon CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use Methane Energies computational fluid dynamics tangentially fired coal boiler conversion to methane nitrogen oxides heat transfer furnace exit gas temperature |
| title | CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use Methane |
| title_full | CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use Methane |
| title_fullStr | CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use Methane |
| title_full_unstemmed | CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use Methane |
| title_short | CFD Evaluation of Heat Transfer and NOx Emissions When Converting a Tangentially Fired Coal Boiler to Use Methane |
| title_sort | cfd evaluation of heat transfer and nox emissions when converting a tangentially fired coal boiler to use methane |
| topic | computational fluid dynamics tangentially fired coal boiler conversion to methane nitrogen oxides heat transfer furnace exit gas temperature |
| url | https://www.mdpi.com/1996-1073/15/1/246 |
| work_keys_str_mv | AT kangminkim cfdevaluationofheattransferandnoxemissionswhenconvertingatangentiallyfiredcoalboilertousemethane AT gyubokim cfdevaluationofheattransferandnoxemissionswhenconvertingatangentiallyfiredcoalboilertousemethane AT byounghwalee cfdevaluationofheattransferandnoxemissionswhenconvertingatangentiallyfiredcoalboilertousemethane AT yoonhobae cfdevaluationofheattransferandnoxemissionswhenconvertingatangentiallyfiredcoalboilertousemethane AT chunghwanjeon cfdevaluationofheattransferandnoxemissionswhenconvertingatangentiallyfiredcoalboilertousemethane |