Conversion of bio-solids (scum) from tannery effluent treatment plant into biodiesel

The search for a suitable low cost feedstock for the production of biodiesel has resulted in biodiesel being produced from bio-solids (scum) taken from the tannery effluent treatment facility. The effectively extracted oil was subjected to combined esterification and transesterification using an acid catalyst. The process was optimized for parameters like catalyst concentration, temperature, time, oil to methanol molar ratio and stirring rate. The result was the yield of 0.55 kg of biodiesel from 1 kg wet scum. The physicochemical properties of the produced biodiesel are in the acceptable range of fuel used in diesel engines. The paper also addresses the quality issues regarding minor components like heavy metals and aromatic contents.