Comparative Boiler Performance, Fuel Cost and Emission Characteristic of Co-firing Palm Kernel Shell with Coal on Circulating Fluidized Bed Boiler: An Experimental Study

The co-firing of palm kernel shell (PKS) was carried out at the circulating fluidized bed boiler at power plant X with 10 MWe and power plant Y with 110 MWe to determine the main changes in operating parameters, fuel costs, and resulting emission products. This study using direct co-firing with the existing fuel line without making modifications to the boiler. The mixing process with a ratio of 5% PKS is carried out at the coal yard manually. Data recording, monitoring parameters, and sampling measurement are carried out under the performance testing standards. Performance test result when the co-firing conditions are evaluated with performance test result on the baseline conditions uses 100% coal. The result shows that co-firing test of 5% PKS at power plant X reduces furnace exit gas temperature (FEGT) and the bed temperature and increases the specific fuel consumption (SFC). Meanwhile, co-firing at 5% PKS at power plant Y reduces FEGT, bed temperature, and the SFC. Using SFC and fuel prices data, co-firing 5% palm shell at both power plants saves fuel costs of 5.09 Rp/kWh and 3.70 Rp/kWh, respectively. Furthermore, co-firing 5% PKS in both powerplants tends to reduce SO2 and NOx emissions. The amount of exhaust gas emissions, both SO2 and NOx, still meets Indonesia’s emission-quality standards based on the Minister of Environment Regulation Number 15 of 2019 with a maximum value of 550 mg/Nm³.