Investigation of Ammonia Co-firing Effects on Combustion Equipment Performance in an Existing PLN 660 MW Coal-fired Power Plant

In Indonesia's electricity system, coal-fired power plants (CFPP) have a vital role in meeting the primary needs of the community.On the other hand, the energy transition agenda forces PLN (State Electricity Company) to observe the options to decarbonize while maintaining the operation of the CFPP to continue operating at least until near the end of its lifetime.One of the hottest and newest programs in Indonesia is ammonia co-firing.Ammonia, a non-carbon fuel, can partially replace coal for combustion in boilers.Applying to existing boilers will certainly shift the existing operating profile, especially on the combustion side.The investigation shows that co-firing ammonia will affect the boiler performance, fuel consumption, draft system, and emission reduction.The boiler efficiency becomes slightly lower with the presence of ammonia.Based on the study result on the existing 660 PLN CFPP, the boiler efficiency will slightly degrade by about 3.6% from 85.7% to 82.6% on an HHV basis.For that reason, the fuel consumption in the boiler should be increased to maintain the amount of heat transfer to the steam cycle.Hence, it can keep the power plant output.On the draft system, it shows that there is a concern about the ID fan.The combustion flue gas has a lower density, which increases the flue gas volumetric.When the volumetric flow increases, the work of the ID fan will also increase.On GHG emission, ammonia co-firing possibly reduces CO2 emission production by about 29.26% at a 30% cofiring ratio.Then, for non-GHG emissions, SO2 and particulate emissions of the CFPP will be decreased by approximately 25.34% and 25.81%, respectively.Nevertheless, initiating ammonia co-firing is a good and exciting option for conducting decarbonization in the existing power plant.