Evaporation is the only practical way to get to zero discharge, but the cost is high. The starting material is heated in an inert atmosphere to convert it to pure carbon. The way it is processed results in a very high surface area and an ability to adsorb various material. The capacity for both organic and inorganic materials is high but carbon is usually used for adsorbing organics. Each organic and each type of carbon have a different adsorption capacity.
Carbon is used to adsorb organics, chromates, sulfides and chlorine.
The following schematic shows a recycling schematic as would be used at a plating shop. Some of the details are left off to increase the clarity of the drawing. Instead of the MRIX system, a microfiltration unit or a clarifier with very good final filtration could be used. After the MRIX the water has been filter and is carbon treated to remove any residual oxidizers or organics. The second system is a complete front end reverse osmosis system with reverse osmosis feed water storage and pH adjust and full city water pretreatment.