Abstract: This invention refers to a method for preparing a chemical digester characterized by using organic and inorganic elements used for multiple purposes such as an accelerator in the decomposition of organic matter, as a water flocculant, as an organic soil fertilizer and as a means to eliminate the concentration of flies and other inserts in organic matter to decompose. The method comprises heating water in a reactor at a temperature of 38° C., adding a polysaccharide, an anti-thickener and an antifoam. The method then comprises the addition of two organic acids, one of them previously mixed in a second reactor and, finally, an inorganic acid until the mixture is homogenized. Optionally the method comprises the packaging of the mixture and the treatment of organic matter.