Review on wastewater treatment technology in coal-fired power plants towards zero liquid discharge in China

Wastewater treatment towards zero liquid discharge (ZLD) in coal-fired power plants (CFPPs) is essential for cleaner electricity production and environmentally sustainable society development. This paper provides a comprehensive review of the latest advancements in wastewater treatment technologies for CFPPs, with a particular focus on China, where Coal-fired power generation remains the predominant method to meet the electricity demand, while the discharge requirements for CFPPs' wastewater is increasingly stringent. First, the paper outlines the sources of the wastewater in CFPPs, the water quality components, and the necessity to achieve zero liquid discharge. Then, it clarifies the current status of existing individual technologies for CFPPs’' wastewater treatment, including their processes, underlying principles, performance metrics, and technical characteristics. Additionally, an economic analysis is conducted on the specific combination processes of ZLD treatment technologies. After that, an in-depth analysis of the challenge arising from current treatment technologies is discussed. Furthermore, some specific strategies for advancing CFPPs' wastewater treatment are proposed. This study aims to summarize the latest advancements in CFPPs' wastewater treatment, thereby shedding light on the future development in CFPPs' wastewater treatment. • The sources and quality characteristics of wastewater from CFPPs are clarified. • Various wastewater treatment technologies are comprehensively reviewed. • The status of zero-liquid discharge treatment in China's CFPPs is systematically analyzed. • Six strategic process combinations are proposed to guide the design of ZLD systems.