Anaerobic digestion of soap stock sludge from refining of vegetable oil and bio-methane potential

摘要

Vegetable oil is produced from oil seeds by crushing and refining, both processes generate byproductsand residues. The aim of refining crude oil is to separate various impurities from the oilto obtain a final product with the required quality according to its future use. This work aims tostudy the manufacturing process of refined vegetable oil and the anaerobic digestion of the soapstock sludge generated during the refining of sun flower oil, to reduce its pollution load, with theobjective of characterizing and applying anaerobic digestion to treat the refined oil sludge andproduce biogas. The study was conducted in two different batches with different organic loadingrates. The first batch was with 0.25g of material volatile per litre volume of reactor (1.35 g soapstock/5L reactor)and the second batch with 0.5g per litre volume of the reactor (2.7g soapstock/5L). The total average biogas produced with this amount of substrate was 1548 mL in 73hrs with net biogas of 743 mL and Bio Methane Potential (BMP) of 413 mL CH_4/g MV. Thestudy showed that the biodegradability of soap stock sludge is possible but it would be slow, asanaerobic digestion of soap stock sludge could be an environmental friendly treatment of thiswaste.