Cost-benefit Analysis Of Desulfurization And Denitration Technologies For Coal-fired Power Plants

Recently, the complex air pollution issue such as haze has aroused a great deal of attention in society, which cause serious damage to public health. According to the source apportionment, sulfate and nitrate have contributed a lot to PM2.5. Coal-fired power plant, as one of the important pollution sources of SO2and NOx, has been supervised to reduce pollution emissions since the10th Five-Year Plan. It proved to be fruitful, but the situation is still grim, it is necessary to enact policies to promote further action for the control of air pollution of the power industry. Aiming at the forthcoming policy, to carry out the research of economic input and effect analysis is of great significance for scientific policy making. This study aims at studying on cost-benefit of desulfurization and denitration control technologies in coal-fired power plants, so as to provide economical support and scientific advice for the subsequent related policies.For desuffurization, the cost-benefit evaluation system has been established taken several factors into considerations including the unit capacity, sulfur content, the desulfurization efficiency, unit load, utilization time, control technology, technical genre, furnace type, coal quality, regions and so on. Taking limestone gypsum WFGD as an example, the cost-benefit calculation model has been established considering the unit capacity, sulfur content, the desulfurization efficiency, utilization time, furnace type, coal quality and regions. Combined with the designed performance curves of mass balance, the equipment performance curve of operation and the sensitivity analysis method, the desulphurization cost-benefit database has been established based on the unit capacity, sulfur content, the desulfurization efficiency, utilization time, limestone prices, electricity prices and water prices, in addition, the cost-benefit spectrogram have been developed. Spectrogram provide different performance parameters such as operation costs per power generation, removal cost per ton SO2, SO2emission performance and SO2reduction benefits per power generation under different unit capacity, sulfur content, and desulfurization efficiency. Based on the database, scenario analysis has been developed, it turns out that compared with achieving emission limit in general regions, when achieving emission limit in key areas, removal cost per ton SO2has increased by13%-19%, furthermore, to achieve ultra-low emissions limit than emission limit in key areas, removal cost per ton SO2has raised5%-8%. Moreover, with the same cost and sulfur content, the emission performance of300MW is1/8times as much as that of50MW, and with the same cost, SO2reduction benefits performs better in large units.For denitration, the cost-benefit evaluation system has been established taken several factors into considerations including the unit capacity, NOx inlet concentration, the denitration efficiency, unit load, utilization time, control technology, technical genre, furnace type, coal quality, regions and so on. Taking SCR as an example, the cost-benefit calculation model has been established considering the unit capacity, NOx inlet concentration, the denitration efficiency, utilization time, furnace type, coal quality and regions. Combined with the designed performance curves of mass balance, the equipment performance curve of operation and the sensitivity analysis method, the denitration cost-benefit database has been established based on the unit capacity, NOx inlet concentration, the denitration efficiency, utilization time, catalyst prices, electricity prices, reductant prices and steam price, in addition, the cost-benefit spectrogram have been developed. Spectrogram provide different performance parameters such as operation costs per power generation, removal cost per ton NOx, NOx emission performance and NOx reduction benefits per power generation under different unit capacity, NOx inlet concentration, the denitration efficiency. Based on the database, scenario analysis has been developed, it turns out that compared with achieving emission limit in key regions, when achieving ultra-low emission limit, removal cost per ton NOx has increased by2%-5%, Moreover, with the same cost and NOx inlet concentration, the emission performance of100MW is1/2times as much as that of50MW, and with the same cost, NOx reduction benefits performs better in large units.