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The Global Environmental Engineers, 2015
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Water, Air, and Soil Pollution, 2005
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Process Safety and Environmental Protection, 2009
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Journal of the Air & Waste Management Association, 2003
The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and ... more The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.
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Journal of the Air & Waste Management Association, 2010
The Hsinta and Nanpu Power Stations are located in southern Taiwan. The Hsinta Power Station cons... more The Hsinta and Nanpu Power Stations are located in southern Taiwan. The Hsinta Power Station consists of five combined-cycle gas turbines (CCGT), whereas the Nanpu Power Station consists of four. A project was undertaken to develop and deploy a predictive emissions monitoring system (PEMS) on CCGT unit 3 of Hsinta Power Station (HT-3) and CCGT unit 1 of Nanpu Power Station (NP-1) with the long-term goal of developing a universal model for this kind of power plant. After the first-year PEMS project at the Hsinta power plant, one goal of the second-year PEMS project was to set up a second PEMS at the Nanpu power plant and compare the PEM models applied the to two gas-fired combined cycle power generation units. Consequently, the second and third PEMS of Taiwan at CCGT HT-3 and NP-1 were finished. After comparing the differences among HT-1, HT-3, and NP-1 PEMS models, the pattern of model functionality indicated that this model could be applied to the other units of the same type and size. However, the PEMS function constant or parameter coefficients must be modified on a case-by-case basis. With regard to the PEMS model developed for HT-3, the relative accuracy (RA) of the 15-variable model with start-up mode is only 7.43% and met the criteria of draft PS-16. With regard to the PEMS model developed for NP-1, the RA of the 10-variable model with start-up mode was only 7.76% and also met the criteria of draft PS-16.
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Journal of Environmental Engineering, 2003
ABSTRACT
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Atmospheric Environment, 2005
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Water Air and Soil Pollution, 2003
The wet scrubbing combined SOx/NO removal system is one ofthe advanced air pollution control devi... more The wet scrubbing combined SOx/NO removal system is one ofthe advanced air pollution control devices. This study tries tounderstand the kinetics of the absorption in the system. The absorption of SO2 and simultaneous absorption of SO2 and NO, whose concentrations are typical for flue gases emittedfrom coal-fired power plants, in a stirred tank reactor with NaClO2/NaOH solutions were carried out at 50 °C.The liquid-side and gas-side mass transfer coefficients of the system were determined. The results indicate that the absorptionof SO2 is completely gas-film controlled if the NaOH concentration is greater than 0.1 M or the NaClO2 concentration is greater than 0.2 M. Adding SO2 would decrease the absorption rate of NO; however, the addition of NO has no effect on the absorption rate of SO2. The existence of O2 has no significant effect on the absorption rate of SO2 and NO in the combined SOx/NO removal tests.
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Journal of Environmental Science and Health Part A-toxic/hazardous Substances & Environmental Engineering, 1998
Absorptions of NO by neutral and alkaline solutions of KMnO4 were performed in this study to clar... more Absorptions of NO by neutral and alkaline solutions of KMnO4 were performed in this study to clarify the reaction kinetics. The experiments were mainly carried out under 50°C, which is the common operating temperature for wet scubbers.According to the assumption that the absorption of NO was developed under the fast pseudo‐mth reaction regime, which is verified in the experiments, the absorption rate of NO into KMnO4 solutions is found to be negative half‐order dependent on PNO and first‐order dependent on [KMnO4]. The addition of NaOH into the solutions of KMnO4 would increase the absorption rate of NO. The absorption rate of NO at 25°C is lower than that of 50°C. In the ranges of this study, the absorption rate of NO would not change by changing the gas flow rate and O2 concentration. NO2‐ is the dominate ion in the liquid phase for this study. However, the [NO3‐]/[NO2‐] ratio increases with the increasing NaOH concentration.
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Journal of Hazardous Materials, 2001
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Journal of Environmental Science and Health Part A-toxic/hazardous Substances & Environmental Engineering, 2001
The operating conditions of this study were closed to the typical operating conditions of flue ga... more The operating conditions of this study were closed to the typical operating conditions of flue gas desulfurization system in the coal-fired power plant. The objective of this study was to investigate the absorption performance of lean NO in an aqueous solution of acidic sodium chlorite using a bench-scale spraying column. The NO conversion and NOx removal efficiency were increasing with the increasing NO concentration, retention time, sodium chlorite concentration, operating temperature, and decreasing initial pH of solution. As the sodium chlorite concentration were higher than 0.4 M, the NO conversion and NOx removal efficiency were 100% and 80%, respectively. The NO conversion and NOx removal efficiency under initial pH 4-7 were higher than that of initial pH > 7. It meant that this process might be suitable to combining with traditional wet flue gas desulfurization system. As the NO2/NOx ratio in the effluent gas was closed to 0.5, it might be suitable to be absorbed in the second scrubbing column operated under alkaline condition.
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Journal of Environmental Engineering-asce, 2003
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Science of The Total Environment, 2001
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Journal of Hazardous Materials, 2000
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The Global Environmental Engineers, 2015
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Water, Air, and Soil Pollution, 2005
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Process Safety and Environmental Protection, 2009
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Journal of the Air & Waste Management Association, 2003
The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and ... more The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.
Bookmarks Related papers MentionsView impact
Journal of the Air & Waste Management Association, 2010
The Hsinta and Nanpu Power Stations are located in southern Taiwan. The Hsinta Power Station cons... more The Hsinta and Nanpu Power Stations are located in southern Taiwan. The Hsinta Power Station consists of five combined-cycle gas turbines (CCGT), whereas the Nanpu Power Station consists of four. A project was undertaken to develop and deploy a predictive emissions monitoring system (PEMS) on CCGT unit 3 of Hsinta Power Station (HT-3) and CCGT unit 1 of Nanpu Power Station (NP-1) with the long-term goal of developing a universal model for this kind of power plant. After the first-year PEMS project at the Hsinta power plant, one goal of the second-year PEMS project was to set up a second PEMS at the Nanpu power plant and compare the PEM models applied the to two gas-fired combined cycle power generation units. Consequently, the second and third PEMS of Taiwan at CCGT HT-3 and NP-1 were finished. After comparing the differences among HT-1, HT-3, and NP-1 PEMS models, the pattern of model functionality indicated that this model could be applied to the other units of the same type and size. However, the PEMS function constant or parameter coefficients must be modified on a case-by-case basis. With regard to the PEMS model developed for HT-3, the relative accuracy (RA) of the 15-variable model with start-up mode is only 7.43% and met the criteria of draft PS-16. With regard to the PEMS model developed for NP-1, the RA of the 10-variable model with start-up mode was only 7.76% and also met the criteria of draft PS-16.
Bookmarks Related papers MentionsView impact
Journal of Environmental Engineering, 2003
ABSTRACT
Bookmarks Related papers MentionsView impact
Atmospheric Environment, 2005
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Water Air and Soil Pollution, 2003
The wet scrubbing combined SOx/NO removal system is one ofthe advanced air pollution control devi... more The wet scrubbing combined SOx/NO removal system is one ofthe advanced air pollution control devices. This study tries tounderstand the kinetics of the absorption in the system. The absorption of SO2 and simultaneous absorption of SO2 and NO, whose concentrations are typical for flue gases emittedfrom coal-fired power plants, in a stirred tank reactor with NaClO2/NaOH solutions were carried out at 50 °C.The liquid-side and gas-side mass transfer coefficients of the system were determined. The results indicate that the absorptionof SO2 is completely gas-film controlled if the NaOH concentration is greater than 0.1 M or the NaClO2 concentration is greater than 0.2 M. Adding SO2 would decrease the absorption rate of NO; however, the addition of NO has no effect on the absorption rate of SO2. The existence of O2 has no significant effect on the absorption rate of SO2 and NO in the combined SOx/NO removal tests.
Bookmarks Related papers MentionsView impact
Journal of Environmental Science and Health Part A-toxic/hazardous Substances & Environmental Engineering, 1998
Absorptions of NO by neutral and alkaline solutions of KMnO4 were performed in this study to clar... more Absorptions of NO by neutral and alkaline solutions of KMnO4 were performed in this study to clarify the reaction kinetics. The experiments were mainly carried out under 50°C, which is the common operating temperature for wet scubbers.According to the assumption that the absorption of NO was developed under the fast pseudo‐mth reaction regime, which is verified in the experiments, the absorption rate of NO into KMnO4 solutions is found to be negative half‐order dependent on PNO and first‐order dependent on [KMnO4]. The addition of NaOH into the solutions of KMnO4 would increase the absorption rate of NO. The absorption rate of NO at 25°C is lower than that of 50°C. In the ranges of this study, the absorption rate of NO would not change by changing the gas flow rate and O2 concentration. NO2‐ is the dominate ion in the liquid phase for this study. However, the [NO3‐]/[NO2‐] ratio increases with the increasing NaOH concentration.
Bookmarks Related papers MentionsView impact
Journal of Hazardous Materials, 2001
Bookmarks Related papers MentionsView impact
Journal of Environmental Science and Health Part A-toxic/hazardous Substances & Environmental Engineering, 2001
The operating conditions of this study were closed to the typical operating conditions of flue ga... more The operating conditions of this study were closed to the typical operating conditions of flue gas desulfurization system in the coal-fired power plant. The objective of this study was to investigate the absorption performance of lean NO in an aqueous solution of acidic sodium chlorite using a bench-scale spraying column. The NO conversion and NOx removal efficiency were increasing with the increasing NO concentration, retention time, sodium chlorite concentration, operating temperature, and decreasing initial pH of solution. As the sodium chlorite concentration were higher than 0.4 M, the NO conversion and NOx removal efficiency were 100% and 80%, respectively. The NO conversion and NOx removal efficiency under initial pH 4-7 were higher than that of initial pH > 7. It meant that this process might be suitable to combining with traditional wet flue gas desulfurization system. As the NO2/NOx ratio in the effluent gas was closed to 0.5, it might be suitable to be absorbed in the second scrubbing column operated under alkaline condition.
Bookmarks Related papers MentionsView impact
Journal of Environmental Engineering-asce, 2003
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Science of The Total Environment, 2001
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Journal of Hazardous Materials, 2000
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