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With the growing shortage of water resources in our country and increasing demands for environmental protection, the water and environmental issues faced by thermal power plants will become increasingly prominent. Optimizing the wastewater treatment processes and technologies in thermal power plants to enable the reuse of wastewater holds great social and economic significance. The impurities in desulfurization wastewater from thermal power plants originate from flue gas and the limestone used for desulfurization; they mainly include suspended solids, supersaturated sulfites, sulfates, and heavy metals. Many of these are classified as pollutants that need to be controlled under environmental standards. Due to the special characteristics of this water quality, treating desulfurization wastewater is quite challenging ； At the same time, since various heavy metal ions pose a severe threat to the environment, desulfurization wastewater must be treated separately. The desulfurization wastewater is mixed with the concentrated by-product gypsum and then discharged to the power plant’s dry ash yard for storage. 1. Characteristics of wastewater from thermal power plants 1.1 Characteristics of the wastewater Compared with wastewater from industries such as chemicals and papermaking, wastewater from thermal power plants has the following characteristics: there is a large variation in water quality and volume, and a large number of different types of wastewater can be identified ； The pollutants in wastewater are mainly inorganic substances, while the organic pollutants are primarily oils ； Intermittent drainage is more common. 1.2 Classification of wastewater The same type of wastewater can be reused through the same type of treatment process. Therefore, a reasonable classification is the foundation for the comprehensive utilization of wastewater. Based on the characteristics of water quality and quantity of various types of wastewater generated in thermal power plants, and with the goal of treatment and reuse, such wastewater can be divided into the following categories: 1.2.1 Wastewater with a low salt concentration. 1.2.2 Wastewater with high salt concentration. 1.2.3 Simply treat reusable wastewater. 1.2.4 Extremely poor wastewater that cannot be reused. 2. Treatment of desulfurization wastewater from thermal power plants 1. Neutralization The neutralization process mainly involves two aspects: one is the occurrence of an acid-base neutralization reaction to adjust the pH to between 6 and 9. Second, it precipitates certain heavy metals, causing heavy metal salts such as zinc, copper, and nickel to form hydroxide precipitates. Common alkaline neutralizers include lime, limestone, and sodium hydroxide, while acidic neutralizers include calcium carbonate, among others. 1. Chemical precipitation Heavy metal ions and alkaline earth metals in wastewater are commonly removed using hydroxides and sulfides as precipitation agents; lime and sodium sulfide are the typical reagents used for this purpose. 2. Coagulation and clarification treatment: The wastewater after chemical precipitation contains many tiny suspended particles and colloidal substances; it is necessary to add coagulants to cause these substances to aggregate into larger particles that can then settle. Common coagulants include aluminum sulfate, polyaluminum chloride, ferric chloride, ferrous sulfate, etc ； Common coagulants include lime, polymer flocculants, etc. Company website: http://www.pe1989.com/ Phone: 15861603195 QQ: 1952768141 Address: 1st floor, East Side, Building B, Energy Island, Chuangzhi Industrial Park, No. 201 Jinshan Road, Jiangyin City, Jiangsu Province