GENERALISED INTEGRATION OF SOLID WASTE TREATMENT PRACTICES TO ENHANCE METHANE PRODUCTIVITY, GENERATE SUSPENSION FERTILISER AND UPGRADE BIOGAS

Abstract

This paper presents a general solution of how to link together the treatment of different solid waste: excess sludge, wastes glycerol or fishery residues and waste ash. The aim of the solution is to enhance biogas production and to produce an organic–mineral suspension fertiliser. The enhancement of biogas productivity is achieved by adding waste glycerol from biofuel plants or fish residues from fish farming and fishing industries into anaerobic reactors of wastewater treatment plants. The enhancement of biogas productivity lies in the range of 200–400%. The fertiliser is produced as a mixture suspension on the basis of waste sludge, waste ash and mineral fertilisers. The mixture is treated by mechanical disintegration, which is responsible for homogenisation and dehelminthing. If the pH of the suspension fertiliser must be reduced, the bubbling of biogas through the suspension can be used. The carbon dioxide content is diminished and the calorific value of the biogas is elevated.