The use of clean technologies in the treatment of wastewater from the phosphating of metal surfaces

This article describes a study carried out with the purpose of optimizing the various stages of the treatment used for wastewater produced by the preparation of metal surfaces. The wastewater from the metal washing at the end of the phosphating process presents a high concentration of residual phosphorus and zinc, used for activating the process. The study sought to identify possible alternative forms of treatment for this wastewater in order to minimize water consumption while at the same time obtaining high performance in terms of purification in accordance with the principle of waste minimization. For each possible solution, experimental tests of pollutant elimination were carried out in order to achieve basic information for the plant design.