The purpose of this research is to analyze operating parameters and flue gas emissions of 330 MWe coal fired power plant Pulverized coal boiler type on cofiring test, using wood biomass based, compared to low range coal firing operation. Wood biomass based was chosen because it is most widely available and has great potential to reduce emission and achieve the target of increasing NRE.

The biomass percentage for coal substitution is 5% wood pellets and 5% sawdust. Each scenario was tested at a load of 310 MW gross for 6 hours of operation. Direct cofiring was used in this experiment. Coal and Biomass blended at the coal yard, then through the fuel feeder enters to the pulverized mill evenly to be burned in all positions of furnace burner. The main operating parameters of the biomass cofiring test are mill current, mill outlet temperature, Furnace Exit Gas Temperature (FEGT) and unburned carbon. The environmental impact analyzed are SO₂ and NOX emission on exhaust gas.

Compared to coal firing operating parameters, all biomass cofiring experiments are still within safe limits for operation. The average mill current & MOT has increased but still within the maximum operating limits 40 ampere & 65℃. The average FEGT has decreased but still within maximum operating limit below 1200℃. SO₂ and NOx flue gas emission parameters for all cofiring experiment did not show significant changes compared to coal firing operation. Through CEMS equipment, coal firing and biomass cofiring tests are monitored while comply to government regulations with a maximum value limit of 550 mg/Nm³ for coal fired power plant.

The results of this research can be a consideration for implementing biomass cofiring in safe conditions for operating and environment parameter for maximum percentage of 5% wood biomass based without equipment modification in similar capacity pulverized coal fired power plant.