ABSTRACT
This chapter discusses the treatment of wastewater from the flue-gas desulfurization process in coalfired power plants, focuses on the improved method. A further reduction in the fluoride concentration, if desired, is possible by increasing the amount of NaOH added to the 2nd reactor in the Mg circulation method or by increasing the amount of alum to the 1st reactor in the conventional process. A coal-fired power plant desulfurization wastewater treatment process has been developed. It consists of coagulation for the removal of fluorides and heavy metals and adsorption for the removal of Chemical oxygen demand (COD). After removal of the fluorides and heavy metals, wastewater is filtered and fed to the COD adsorption towers, which are packed with the synthetic adsorbent. The fluoride concentrations and dosage of NaOH in the 1st and the 2nd stages were calculated for a system involving the recycling of sludge containing magnesium hydroxide.
