Abstract: In order to improve the utilization rate of the entire plant water resources, the quality of treated industrial wastewater in one thermal power plant of Hebei Province is compared with the quality requirements of desulfurization process water, which concludes that they are quite close to each other. Since the amount of the treated industrial wastewater accounts for only 7% of the total desulfurization process water, it is decided to use it as desulfurization process water. To further eliminate the risks and make the utilization plan properly, the on-site testing study is carried out. The results show that the desulfurization system runs normally after the treated industrial wastewater is served as the influent water for desulfurization. Meanwhile, this system has a desulfurization efficiency of no less than 95%. The slurry density maintains at 1 130 kg/m³ during the operation process. The water ratio of the gypsum as the desulfurization byproduct is about 10%, and the weight percentage of CaCO₃ is less than 3%. The purity of CaSO₄·2H₂O is above 90%, which satisfies the market requirements for the quality of gypsum. Therefore, the treated industrial wastewater is eligible to be reused in desulfurization process.

Key words: coal-fired plant, industrial wastewater, wastewater reuse, flue gas desulfurization, process water