Biogas Potential of Wastewater Sludge from a Palm Oil Refinery Plant

Abstract

An agri-food company specializing in the processing of crude palm oil into refined oil generates physico-chemical and biological sludge from its SN Cie-coded wastewater treatment plant. This sludge is therefore a management issue. The aim of this study is to valorize the sludge from a wastewater treatment plant located in an industrial zone in Vridi/Abidjan (Côte d'Ivoire) into biogas. The physico-chemical characteristics of the sludge and its methanogenic potential were assessed, followed by optimization of biogas production. These results revealed that the biological sludge (73.08% MS) contained more organic matter than the physico-chemical sludge (55.55% MS). The relatively average organic matter content of the physico-chemical sludge necessitated the use of cow dung as an inoculum to enhance biogas production. Biodegradability tests carried out with different ratios of Substrate/Inoculum led to the conclusion that the presence of a significant quantity of microorganisms is necessary for optimum biogas production. As a result, 6510mL of biogas were produced from the SN Cie wastewater treatment plant's biological sludge, with a methane composition of 71.33%, which is required for power generation.