- Thesis topic: Study on Emission Factor of Stationary Pollution Sources─The boilers

- Doi: https://doi.org/10.6840/cycu202000649

- Abstract: 

        To improve air quality, comprehensive data on emissions inventories will help out Taiwan to develop more effective control measures, understand the contribution of each source of pollution, and conduct classified pollution management based on pollution levels of the source. There are around 15,000 boilers in Taiwan, and most of the equipment for the pollution control from boilers was inefficient or didn’t install any air pollution control device （APCD）. The statistical analysis was conducted by Environmental Protection Agency (EPA) to understand the contribution of air pollutants released by stationary source boilers in Taiwan. TSP, SOx and NOx are approximately 21%, 13% and 10%, respectively. In 2020, the EPA set new air pollutants emission standards for boilers: 30mg / Nm3 of TSP, 50ppm of SOx, and 100ppm of NOx, encouraging boiler manufacturers to upgrade and improve their APCDs. The emission factor (EF) of TSP, SOx and NOx was calculated by the regular inspecting data and the statistical analysis of TSP, SOx and NOx emission factors from coal, oil and gas boilers in the Guanyin industrial zone of Taoyuan city was conducted.
For coal-fired boilers, the estimated EF range of the uncalibrated measured value and calibrated value of TSP is 0.82～8.21 kg/MT and 2.47～17.07 kg/MT, respectively. The estimated EF range of the uncalibrated measured value and calibrated value of SOx is 3.96～6.02 kg /MT and 8.38～13.51 kg/MT, respectively. The estimated EF range of the uncalibrated measured value and calibrated value of NOx is 8.34～12.19 kg/MT and 12.52～17.07 kg/MT, respectively. For APCDs combination for coal-fired boilers, there are 9 combinations in this study, among which Combination C (SCR+ electrostatic precipitator + FGD) is the best selection for reducing the PM, SOx and NOx.
        For oil-fired boilers, the estimated EF range of the uncalibrated measured value and calibrated value of TSP is 0.64～0.87 kg/KL and 0.65～0.94 kg/KL, respectively. The estimated EF range of the uncalibrated measured value and calibrated value of SOx is 14.63～16.70 kg/KL and 15.36～18.21 kg/KL, respectively. The estimated EF range of the uncalibrated measured value and calibrated value of NOx is 5.15～6.01 kg/KL and 5.21～6.66 kg/KL, respectively.
For natural gas-fired boilers, the estimated EF range of the uncalibrated measured value and calibrated value of TSP is 0.009 ~ 0.051 kg/m3 and 0.010 ~ 0.045 kg/m3, respectively. The estimated EF range of the uncalibrated measured value and calibrated value of SOx is 0.010～0.053 kg/m3 and 0.009～0.044 kg/m3, respectively. The estimated EF range of the uncalibrated measured value and calibrated value of NOx is 1.419～2.149 kg/m3 and 1.413～2.140 Kg/m3, respectively.
The calculation of PM10 and PM2.5 emissions from boiler in the Guanyin Industrial Park was further estimated, and comparing with the total industrial emissions in Taoyuan City by the 10th edition of TEDS of 2016. The results showed that the contribution of PM10 to the Guanyin Industrial Park from coal-fired, oil-fired and natural gas-fired boilers are 2.39%, 8.96%, 0.48%, respectively. The contribution of PM2.5 to the Guanyin Industrial Park from coal-fired, oil-fired and natural gas-fired boilers are 1.78%, 9.02%, and 0.58%, respectively.
        It is obvious that the various fuel and processes made a significant impact on the EF of pollutants. The SOx EF from the oil-fired boilers are significantly higher than the announced EF, and the calculated contribution of PM10 and PM2.5 from the oil-fired boilers are also higher than the other two boilers. The results provide valuable information for the EF modification in the future.

Keywords: Emission Factor, Boiler, TSP, SOx, NOx, PM10, PM2.5, Guanyin Industrial Park