온실가스 저감을 위한 암모니아 혼소가 초임계 화력 발전시스템 보일러에 미치는 열성능 영향성 평가

Abstract

Co-firing ammonia with coal is emerging as a transitional technology in the power industry for the major reduction of greenhouse gas emissions. Although ammonia has the disadvantages of low combustion reactivity and the generation of nitrogen oxides, it can effectively reduce greenhouse gas due to the generation of only moisture and nitrogen after the combustion. Therefore, for the efficient co-firing of the coal and ammonia in the power plant system, it is essential to evaluate the effect of co-firing ammonia on the boiler system. We selected the 870 MWe supercritical coal-fired boiler system and developed the process simulation model of the target boiler system. In this study, process simulation of the target boiler system was performed according to the ammonia co-firing ratio of 0, 5, 10, 20, and 30%. In addition, the effect of ammonia co-firing on the boiler thermal performance was evaluated according to the load condition and the quality of coal. As the ammonia co-firing ratio increases, the flue gas flow rate and the radiation and convective heat transfer rate decrease. Accordingly, the main and reheat steam temperatures decrease. Although the reduction of carbon dioxide is quantitatively confirmed according to the co-firing ammonia, the boiler thermal efficiency decreases due to the increase in the amount of moisture in the flue gas.