Co-firing RDF in CFB Boiler Power Plant

Abstract

Biomass co-firing in coal fired power plant especially in circulating fluidized bed (CFB) boiler is being tested in several power plants in the world. This report addresses operational issue for cofiring refused derived fuel (RDF) in circulating fluidized bed boiler. The main operational parameters being monitored are temperature and pressure distribution in the furnace, which are represent the fluidization condition and fuel combustion itself. Another operational parameter needed to be monitored are flue gas compositions which are represent the emission effect of the fuel type. The RDF used in this cofiring produce in Klungkung-Bali, which is produce from local municipal solid waste with bio-drying method developed by STT PLN. The RDF produced by this method can reach calorific value around 3270 kcal/kg, with more than 95% organic matters containment. During cofiring application at 5% RDF, the main parameter changes only on furnace pressure differential which is rise up the amount of excess air (O2) was indicated to be 6% higher and CO2 was 4% lower. RDF pellets also contain less sulfur when compared to coal, the lower SO2 and H2S indicates a reduction in sulfur emissions. The lower NOx shows a positive indication of a reduction in greenhouse gas emissions.