Last month, we began discussing the journey from dilution to zero liquid discharge. I highlighted that approximately 70% of the used process water (UPW) is generated from the dilute stream. This significant volume underscores the necessity for effective treatment processes that ensure the safe return of water into the production cycle while minimising environmental impact.
Figure 1: An overview of the major components to design a ZLD, closed-loop, water recycling system.
To this end, a multi-faceted approach is employed to treat the UPW and reclaim it for reuse. The treatment process begins with advanced oxidation (AOX), a sophisticated technology designed to break down organic pollutants in the water. This method utilises powerful oxidising agents to generate hydroxyl radicals, which are highly reactive and effectively decompose organic contaminants. By deploying AOX, facilities can significantly reduce the levels of chemical oxygen demand (COD) and other harmful substances often found in process water.
To this end, a multi-faceted approach is employed to treat the UPW and reclaim it for reuse. The treatment process begins with advanced oxidation (AOX), a sophisticated technology designed to break down organic pollutants in the water. This method utilises powerful oxidising agents to generate hydroxyl radicals, which are highly reactive and effectively decompose organic contaminants. By deploying AOX, facilities can significantly reduce the levels of chemical oxygen demand (COD) and other harmful substances often found in process water.
To continue reading this article, which appeared in the May 2026 I-Connect007 Magazine, click here.