ZLD processes begin with pre-treatment and evaporation of an industrial effluent until its dissolved solids precipitate. These precipitates are removed and dewatered with a filter press or a centrifuge. The water vapor from evaporation is condensed and returned to the process.
In the last few decades, there has been an effort from the water treatment industry to revolutionize high water recovery and ZLD technologies.
This has led to processes like electrodialysis, forward osmosis, and membrane distillation.
A quick overview and comparison can be seen in the following representative table: