The Wire
Mapping the seed corpus: where the water industry's suppliers cluster ◇ Desalination past the 100-million-m³/day mark: what the project data shows ◇ Tracker: China's water agenda — reuse mandates, sponge cities, leakage targets ◇ EU adopts recast Urban Wastewater Treatment Directive ◇ Beyond capture: PFAS destruction technologies move from lab to field ◇ India's Jal Jeevan Mission passes three-quarters of rural households connected ◇ US EPA finalizes first national PFAS drinking-water standards ◇ Thames Water crisis deepens as shareholders withhold new equity ◇
StubLast reviewed: 2026-06-10

Zero Liquid Discharge (ZLD)

Zero liquid discharge is a treatment strategy that eliminates liquid waste discharge by concentrating and crystallizing dissolved solids, recovering nearly all water for reuse. It is used where discharge is restricted or water is scarce, notably in Chinese and Indian industry.

Overview

ZLD systems maximize water recovery through a cascade: membrane concentration (RO, sometimes high-pressure or brine-concentrator RO) followed by thermal evaporation and crystallization to produce a dry solid. Energy-intensive by design, ZLD is deployed where regulation forbids discharge or where water scarcity makes recovery economic.

China's stringent discharge rules for sectors such as coal chemicals made it a major ZLD market; India's textile and power industries are others. This article is a stub pending expert review.

References
  1. [1]Zero Liquid Discharge: A Review. Environmental Science & Technology, 2016.