Fertilizer & Biogas

Resource Recycling versus Waste Disposal

"One truly noteworthy point is that while the animal tissues and carcasses may be called "wastes", the sterile hydrolyzate produced from them by alkaline hydrolysis is no longer a waste but a resource. This undiluted hydrolyzate, a 5%-7% solution of amino acids, small peptides, sugars, soaps, and electrolytes, is a valuable and versatile nutrient source that can be used as fertilizer, either liquid or dried and solid, as an additive to composting systems, or as a feedstock for anaerobic digestion biogas generation plants that produce methane, steam, heat, and electric power. Biodiesel applications for the hydrolyzate are also being actively explored. 

In Europe, where there are shortages of both sewage treatment capacity and of energy resources, it is most likely that the hydrolyzate will be used for biogas generation. As alkaline hydrolysis becomes the method of choice for destroying the specified risk material (SRM) generated by application of the new USDA regulations for slaughtering cattle, it is likely that large conversion plants for the manufacture of one or more of these secondary products from the hydrolyzate or for the recovery of the energy stored in that solution will become a significant part of the rendering industry".

 (https://www.alnmag.com/article/2004/08/alkaline-hydrolysis-process)