Case Studies in Chemical and Environmental Engineering (Dec 2024)
Development of particulate matter emission factors based on CEMS data from PT PLN (Persero)-Owned coal-fired power plants
Abstract
In the operation of coal-fired power plants (CFPPs), the generation of particulate matter (PM) is monitored using a continuous emission monitoring system (CEMS); this data is useful for emission dispersion, planning, and reduction. However, due to local variability in the coal used, control technologies, and policies, emission factors need to be established. Notably, no PM emission factor has been derived or can be applied to CFPPs owned by the National Electricity Company of Indonesia/PT PLN (Persero) and other CFPPs. This study considered 52 CEMS-equipped CFPP units with emission factor values differing according to the boiler type, installed capacity, and air pollution control device (APCD). The PM concentration, volumetric flow rate, coal consumption, and electricity production data were assessed to determine PM emission factors for these units. A correlation test was also conducted to determine the effect of various parameters (based on the boiler type, installed capacity, and APCD type) on the PM emission factor by categorizing the CFPP units into two or three similar subcategories.Furthermore, using calorific values and carbon contents, dynamic emission factors were developed – expressed in terms of a simple or multiple linear regression equation – and their accuracy was determined. The different configurations of the 52 investigated CFPP units led to variations in the obtained emission factor values. The precision of the PM emission factors was enhanced by grouping the CFPP units based on similarities in the boiler type, installed capacity, or APCD type. The boiler type (represented by the superficial gas velocity) has the largest influence on the emission factor (in g PM/kg coal), with a moderate positive correlation, followed by the type of APCD installed (represented by the theoretical PM removal efficiency) and the installed capacity (represented by the heat rate or specific coal consumption). The dynamic PM emission factor is expressed by the equation y = 0.763 + (−0.016x), where only the fixed carbon content (from the proximate analysis results) – the independent variable on the x-axis – has a significant correlation with it.
