BIOMASS COFIRING FOR REDUCING CARBON EMISSIONS IN COAL FIRED POWER PLANT

• Main Author: Setiana B, Verinda
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/74068
• Institution: Institut Teknologi Bandung

Steam Power Plant (PLTU) is a power plant that uses coal fossil fuel as an energy source to generate electricity. Burning coal at coal-fired power plants will produce by-products in the form of Greenhouse Gases (GHG), namely carbon dioxide (CO2), nitrogen oxides (NOx) and sulfur dioxide (SOx) which will have an impact on the environment in the form of global warming and climate change. To reduce CO2 emissions and other greenhouse gases from the power generation sector and also the commitment to realize the achievement of the national energy mix of 23% by 2025, the government through PT. PLN created a biomass cofiring program at coal plants. Cofiring is a method of mixing coal and biomass with a certain percentage which is then burned in the boiler. This study aims to analyze the emission characteristics and combustion performance of the direct cofiring method with feed in the form of a mixture of subbituminous coal and palm kernel shell carried out on a laboratory scale. The emission characteristics to be analyzed are in the form gas composition of CO, CO2, and NOx. Meanwhile, the combustion performance to be analyzed in this study is in the form of Furnace Exit Gas Temperature (FEGT) and combustion efficiency. The cofiring process is carried out directly in the cylindrical furnace. In this study, variations in the mass ratio of biomass used and variations in primary air ratio (PAR) will be carried out. PAR is a match between the primary air flow rate and the total combustion air. In variations in the mass ratio of PKS biomass, coal and biomass fed in the form of fuel mixtures with variations in biomass mass fractions of 0%, 3%, 5%, and 10% where PAR is set constant at 0.531. Meanwhile, in the PAR variation, the ratio of primary air flow rate to total combustion air is set at 0.524; 0,531; and 0.545 with a PKS mass ratio of 5%. The results showed that the biomass mass ratio of 3%-10% can reduce the composition of CO2 by 21.7%-26.45% compared to burning 100% coal. In addition, cofiring with a biomass mass fraction of 3%-5% can reduce NOx gas emissions in exhaust gas by 3.03%-21.68%. However, an increase in the mass ratio of biomass can increase the CO gas content in the exhaust gas. Meanwhile, an increase in biomass mass fraction by 3%-5% can reduce Furnace Exit Gas Temperature (FEGT) by 7.27%- 19.05% and can increase combustion efficiency by 1.12%-5.18%. In the PAR variation, an increase in the PAR value from 0.524 to 0.545 can reduce the composition of CO2 gas by 3.7%, can increase the composition of CO gas by 12.2% and can increase the composition of NOx gas by 6.9%. The increase in the PAR value in the cofiring process