Impianti trattamentoACQUE REFLUE

Home / zero-liquid-discharge

Zero liquid discharge

Process solutions and Zero Discharge treatment systems for industrial waste water. Treatment processes designed for various types of industrial applications.

The request to receive zero discharge water treatment systems is becoming a growing requirement for companies. The reasons are not only connected with the will to adopt green policies but also because of problems such as: the impossibility of complying with the discharge limits or poor water availability.

The design philosophy at the bottom of the zero discharge proposed by SAITA rests on dividing the flows of the waste water generated by the production line according to the characteristics and concentrations of the pollutants.

The principle of dividing the flows aims at optimizing the treatments in order to remove specific pollutants with the best available technology. In fact, treating a mixture of contaminated water with variable concentrations and characteristics makes the application of zero discharge more costly and less effective.

The concepts developed by SAITA as to zero discharge are applied in the following environments: metal surface treatments, anodizing, printed circuit boards (PCB), powder coating, washing lines, electronic and photovoltaic industries, etc.

A process study is carried out for every industrial application and every individual customer, aimed at identifying the best zero discharge treatment chain in terms of: cost-effectiveness, operational management and final quality of the recycled water.

IWT series // Zero liquid discarge for photovoltaic solar cells production

Integrated system for the closed circuit treatment of process water deriving from the production of photovoltaic cells. The IWT (Integrated Waste water Treatment) Series system is a closed circuit treatment system, integrated with the production line of multicrystalline silicon cells, that allows recovering 97% of the treated water. The IWT process, started in 2008, is designed to treat any type of waste water generated by the silicon cell production line. Passing through various treatment phases in the IWT system, the discharged water becomes progressively purer and can be reused to supply the photovoltaic cell production systems. The only waste produced by the whole system is an inert solid sludge.

Desulfate process // Zero liquid discharge

The DESULFATE chemical-physical treatment applied to treat water containing high concentrations of metals and sulphates (e.g. metal wire pickling, powder coating and aluminium anodizing) allows recovering the treated water as wash water. Developed in 2012, this process has proved to be an innovative process in comparison with the traditional zero discharge systems that provide for treatment with: a traditional chemical-physical system, reverse osmosis systems and large size evaporators.


  • Total recovery of the water treated in the production cycle
  • Elimination of the discharge of liquid waste
  • Disposal only of solid waste or concentrated liquids
  • Drastic reduction in water consumption
  • Constant control of the quality of the recycled water
  • Elimination of the problems connected with discharge permits


Standard and Custom plants