This is industrial wastewater.
Wastewater containing coal can be classified as a type of industrial wastewater. Industrial wastewater refers to wastewater containing pollutants produced during industrial production processes. Coal-containing wastewater refers to wastewater generated during coal mining, coal processing, coal-fired power generation, etc.
During coal processing, wastewater may contain solid waste and chemical substances such as coal gangue, coal ash and cinders. Wastewater discharged from coal-fired power plants can contain coal ash, ash, coal waste, and combustion pollutants, which can harm the environment and ecosystems.