Abstract

This study was conducted with the purpose of empirically comparing and analyzing the reaction efficiency and cost-effectiveness of sodium bicarbonate (NaHCO₃) and highly reactive hydrated lime (Ca(OH)₂), which are used as acid gas neutralizing agents in the Dry Reactor (DR) process of waste incineration facilities. The subjects of the study were selected from four incineration facilities at industrial sites with similar incineration capacities and air pollution control facility configurations. Based on actual operating data, the amount of neutralizing agents used, the amount of fly ash generated, and the amount of agents used in downstream wet scrubbing facilities were comprehensively compared. As a result of the study, an analysis was conducted by converting chemical costs, fly ash treatment costs, and wet scrubbing facility chemical costs based on the same incineration volume. The study found that the application of sodium bicarbonate resulted in a reduction of total operating costs ranging from a minimum of 9.1% to a maximum of 27.8% compared to slaked lime. This is attributed to the reduced load on downstream pollution control facilities and lower fly ash treatment costs due to the high reactivity of sodium bicarbonate. Therefore, it was confirmed that when selecting neutralization chemicals for the acid gas treatment process in waste incineration facilities, it is necessary to evaluate treatment efficiency by comprehensively considering not only the unit price of the chemical but also reaction efficiency, fly ash generation characteristics, downstream facility operating costs, and environmental impact.