Zero Liquid Discharge (ZLD) refers to the concentration and transfer of pollutants in industrial wastewater, maximum reuse (over 99%), no waste liquid discharge. After comprehensive treatment of industrial wastewater by combination process, pollutants will be discharged in the form of solid. The concentrated, crystallized waste salt will be then sent to landfill or further processed into useful chemical raw materials.

ZLD is a whole-plant design-based wastewater treatment solution, which involves both reduction of wastewater at source and internalization of wastewater, as well as treatment and concentration of wastewater at the end. In operation, due to the complexity of water quality and the secondary treatment of solid waste, there is a problem of operation cost to achieve the goal of ZLD. Concentration and salt separation based on membrane application are the key processes to make ZLD economical, reducing operating costs and secondary treatment costs. As a provider of membrane separation technology solutions, Keysino is committed to providing industrial customers with ZLD solutions, which are "win-win" for both economic and environmental benefits.