The Features And Treatment-System Renovation Of The Wet Flue Gas Desulphurization-Wastewater In Thermal Power Plant

This paper summarized the present situation and development trend of coal-fired power plant desulfurization technology in China, and in detail described the process characteristics of wet flue gas desulfurization, half dry flue gas desulfurization and dry flue gas desulfurization technologies. The components and concentration of desulfurization wastewater from wet limestone-gypsum system installed in power plant were determined. The performance of chemical precipitation which was used as a global prevailing technology to removed heavy metals and suspend granule, was analyzed in this paper. Some new developing methods, such as fluidized bed and precipitation-microfiltration, were also introduced. The problems of chemical precipitation existing in the practical treatment system of desulfurization wastewater in Zheneng Yueqing power plant were discussed. Some corresponding solutions for the desulfurization wastewater extraction system were presented to reduce solid-containing content in wastewater, to increase the effective commissioning rate of wastewater treatment system and decrease the desulfurization absorption tower serum chlorine ion content. A good result was obtained through optimal modification for the treatment system, the amount of solid-containing desulfurization wastewater decreased from1.71%to0.34%, and the content of chlorine ion from absorption tower down was lowered from16816mg/L to9539mg/L. The operation of desulfurization wastewater treatment system maintained stable and the discharge concentration and rate of pollutants were below the criteria values.