Valorization of urban sewage sludge: Aerobic composting with banana peel, rice straw and eucalyptus leaves

Abstract

The disposal of urban wastes and sludge from wastewater treatment plants (WWTPs) is an issue of growing importance;which hinders urban development in developing countries like it is the case in Africans’ countries. Here we have investigated the composting of sewage sludge with (1) banana peel (BP) and (2) mixture of rice straw-eucalyptus leaves (RS-EL) as bulking materials. Results shown good performance of both materials, and very good humification of organic matter and decomposition rates were estimated for about 41.4% and 50.3%, respectively in the compost with BP and with RS-EL. Physicochemical properties [pH (7.4 - 7.8) and electrical conductivity (EC, 3.29 – 3.58 mS cm-1)] of the produced composts favored its utilization in agricultural soil as fertilizer. However, further investigation on the degradation of organic micro pollutants and the mobility of heavy metals is still needed to fully appreciate the safety of such compost.