The invention relates to the field of process engineering and concerns a method for treating waste products, as can be used for example in the treatment of low-viscosity waste products with organic acids from the milk-processing industry. The problem addressed by the present invention is that of providing a method that achieves a much better treatment and/or use of the valuable constituents of the waste products in terms of their energy and material content. The problem is solved by a method in which waste products are first made to undergo an anaerobic fermentation and precipitation to produce biogas, the liquid phase with solid fractions that is obtained is subjected to a magnesium ammonium phosphate precipitation (MAP precipitation), then the liquid phase with solid fractions obtained in the MAP precipitation is passed on for filtering, the permeate of the filtering is subsequently passed on for electrochemical oxidation, and after that the anolyte of the oxidation is made to undergo a reverse osmosis reac
