DESIGN AND CONSTRUCTION OF PILOT SCALE PROCESS SOLVENT EXTRACTION PLANT FOR NEEM SEED OIL

A pilot Neem oil solvent extraction plant of 9.65kg/day Neem seed kernel capacity was designed and fabricated. Grade 304 stainless steel was used for construction of the extractor, evaporator, condensate receiver and the flat blade turbine impeller. The concept of overall heat transfer coefficient was adopted for calculating the heat transfer areas of the extractor and evaporator and their sizing. The extraction was carried out at 50 o C extraction temperature and particle size of 0.425 – 0.710mm at an efficiency level of 81.91%. The percentage yield obtained was 36.86% when flat blade turbine impeller was operated at 84 rpm for 40 minutes contact time. The GCMS result shows the composition of the extracted Neem oil to be oleic acid, 40.41%; stearic acid, 27.65%; palmitic acid, 25.36%; octanal, 3.90%; elaidic acid, 1.23%; lactone, 0.97%; and methyl stearate, 0.48%. This percent composition compares favourably with literature values. The properties of the Neem oil were found to be: specific gravity, 0.9111; pH, 6.5; refractive index, 1.4668; iodine value, 70.21g/g; acid value, 34.33mgKOH/g and Saponification value, 180.95 mgKOH/g.