The present situation, challenges, and prospects of the application of ammonia-coal co-firing technology in power plant boilers

Co-firing of ammonia-coal can aid in achieving pollution control and carbon reduction, which is of great practical significance in supporting the realization of China's 'dual carbon' goals. This article reviews the research progress and prospects of ammonia-coal co-firing technology in the energy field. Ammonia-coal cofiring is a novel combustion technology that involves the combined burning of ammonia gas and coal, aiming at reducing pollutants and greenhouse gas emissions produced during coal combustion, enhancing energy utilization efficiency, and achieving clean and efficient energy transformation. The review first introduces the physical and chemical properties of ammonia and the advantages of ammonia-coal co-firing technology. Then, it presents the current research progress on the combustion characteristics and NOx generation and emission characteristics of emerging power plant boiler ammonia-coal co-firing technology. Finally, it analyzes and presents the future research direction of ammonia combustion in power plant boilers. Ammonia-coal co-firing can significantly reduce carbon emissions from power plant boilers without significantly altering the furnace temperature characteristics. Although the increase of fuel nitrogen brings forward the risk of NOx emissions, it can be effectively controlled through combustion staging, combustion organization, and other methods. Therefore, ammonia-coal co-firing is a feasible path for carbon reduction. Use of ammonia as a carrier for renewable energy can aid in achieving reduction in carbon emission during various applications, such as heat, electricity, and power, and alleviate or solve the dependence on finite fossil energy, showing enormous development potential and prospects.