Study on Comprehensive Utilization Status and Technical Route of FGD Gypsum from Coal-Fired Power Plants

Abstract

The aim of this paper is to investigate FGD gypsum quality from coal-fired power plants and its comprehensive utilization. FGD gypsum comprehensive utilization technologies mainly include employed in the wallboard manufacture, as cement retarders, as a construction material for roads and as a soil ameliorant. In China, FGD gypsum is mainly utilized to produce wallboard and as cement retarders. FGD gypsum comprehensive utilization technical route was proposed based on FGD gypsum produce, storage, transport and comprehensive utilization. In order to ensure FGD gypsum quality so that it can be well utilized, the following requirements should be satisfied: for FGD gypsum, moisture content (wet basis) should be no more than 10%; CaSO4·2H2O content should be no less than 90%; CaSO4·1/2H2O content should be no more than 0.5%; pH should be controlled between 5 and 9; Cl- content (dry basis) should be no more than 200 mg/kg.