Sulphur removal from flue gases. Pt.2. Double-alkali method and utilization of by-product (CaSO4·2H2O)

The flue gas desulphurization (FGD) technology presented in this paper is designed for a thermal-electric power station. The FGD system receives an hourly volume of flue gases amounting to 530,000 m3 with an average sulphur dioxide concentration of 1.3 g/m3. The FGD process is based on the wet double-alkali method, which ensures: 1) recirculation of the regenerated sorption effluent in the absorption unit, and 2) calcium sulphate sediment as a waste product. In this paper, there is proposed a system for the utilization of the waste product (utilization unit). The processing procedures performed in the utilization unit yield binding materials, commercial gypsum, and building blocks. The FGD process in a no-waste technology which brings about an over 90% abatement of sulphur dioxide and particulate matter emissions. (author). 7 refs, 2 figs