Zero liquid discharge (ZLD) refers to a treatment method where the plant doesn’t release any liquid effluent into surface waters, effectively eradicating any environmental pollution that would have been caused by the treatment process. Aside from this benefit, a ZLD method also effectively utilises wastewater treatment, recycling, and reuse, helping to conserve water by reducing the need for fresh water. The difficulties of ZLD are covered in this chapter in a number of different processing facilities, including bulk medicine producers, textile mills, and chemical and fertiliser plants. Concentrating the effluent utilising several methods, such as membrane-based and multiple effect evaporation-based systems, as well as water recovery and recycling, enables the creation of zero discharge solutions. Tags: Wastewater TreatmentThere is no liquid leakageDrying Membrane separationConcentration of effluent