ABSTRACT
Currently materials released by hen-processing plants are landfilled. An easy for performance and application method for partial hydrolysis by ortho-phosphoric acid of these wastes is described. As a result a small fraction of fat, easily soluble peptone and a homogeneous residue containing calcium and magnesium phosphatesas well as partially degraded protein were obtained. The wastes were hydrolyzed at temperature of 98 ± 5 °C in polypropylene containers that withstand temperatures of up to 135°C.) We consider that the fat could be used for preparation of soap, the soluble peptone—in the microbiology for preparation of broth media for microorganisms, while the insoluble residue—as food for pets or as a fertilizer in the horticulture. The method allows the factory wastes to be transformed into useful products and to avoid their incineration. The implantation of the method in the practice excludes the necessity of application of the EC legislation for destroying biological wastes since such are not thrown away. The results are: saved resources, waste products utilization and avoiding the environmental pollution with toxic nitrogen compounds liberated from the proteins during incineration.