This is a compendium of information provided on the treatment of industrial liquid effluents in a course given by Dr. Ricardo Serra, a university professor of the Liquid Effluents Department, specializing in Chemical Engineering, at the National Technological University, Avellaneda Regional Faculty, in the Postgraduate Course on Labor Engineering. The aim is to reach the reader's understanding that the values allowed by law for dumping permits for these effluents are adequate to avoid the need for any type of chemical treatment in order to achieve values that do not affect either the receiving bodies or the sewage network systems that lead to subsequent treatments to achieve optimum purification of these wastewaters to be reused either as water for industrial use or water to be treated for subsequent purification of the same.