Design and testing of small-scale thin-film palm oil refinery
การออกแบบและทดสอบระบบการกลั่นน้ำมันปาล์มขนาดเล็กแบบฟิล์มบาง

Sunchai Klinpikul, Assoc. Prof., D. of Industrial Eng., F. of Eng., PSU.
Chukiat Kooptanond, Asst. Prof., D. of Mechanical Eng., F. of Eng., PSU.
Chit Limworaphan, Expert, The Royal Project for Small-scale Palmoil Industry, PSU.
Sathien Wanichwiriya, Researcher, Office of Research and Development, PSU.
Corresponding e-mail : ksunchai@ratree.psu.ac.th

Grant : Government Budget
Published : Songklanakarin J Sci Technol 2000, 22(4) : 507-514
Key words : CPO (Crude Palm Oil), RBD (Refining Bleaching Deodorizing), palm oil, thin film, PFAD (Palm Fatty Acid Distilled)

The design and testing improvement of a small-scale palmoil refinery was carried out as a continuity of the development of palmoil refinery under the Royal Project for promotion of small-scale Palmoil Industry. The intended objective is to develop a continuous palmoil refining process which has a higher efficiency than the existing batch refining process. The thin-film refining technique was selected among various semi-continuous and continuous refining processes. A pilot palmoil refinery at a desired production capacity of 9 litres per minute or 12 tons of CPO per day was designed and installed at the Prince of Songkhla University in 1997. Several refining process experiments were carried out and the best result was obtained by raising the temperature of the Palmoil in the thin film column to 250-290oC under vacuum 740 mm. Hg. and using sparging steam at 230oC with a constant pressure of 3 bars. The detention time of palmoil in the thin-film evaporator was 21-35 minutes. The best condition of deacidification and deodorization could be achieved at the refining rate of 5 litres per minute or 6.6 tons per day with a processing cost of 0.87 Baht per kilogram of RBD oil. An economic analysis for 15 - year period under certain assumptions was made and the Internal Rate of Return (IRR) was 24.40% where as the total investment cost is 7.28 million Baht. The IRR was less than the Minimum Attractive Rate of Return (MARR) which is estimated at 30%, therefore it can be concluded that the refinery at this production capacity might not be appropriate to be commercially operated by the small-holder cooperatives. However, further study showed that a larger refinery at the production capacity of at least 16.5 tons of CPO per day would be feasible since the IRR, at 7.00 Baht of price difference between CPO and RBD palm oil, was 34.80% which is higher than the desired MARR. Improvement of the thin-film refining system would be recommended for further study. In addition, the splitting of palm fatty acid which is a by product of refining process in small scale for oleochemical applications should be attempted.
BACK