Performance Evaluation of a Gas-fired Vacuum Evaporator for Drying Coconut Oil
Author : Altamarino III, Alvin Maximo Abelito
Major Adviser : Lozada, Ernesto P.
Committee Members : Alcanzare, Edilberto A.; Arquiza, Apollo C.; Manoto, Russel D.
Year : 1994
Month : April
Type : Thesis
This manuscript can be accessed:
The performance of gas-fired vacuum evaporator was tested and evaluated for drying coconut oil. The drying conditions tried were heating the oil up to 100°C, 115°C, and 130°C under a vacuum of 15 in.Hg. Fifty liters of coconut oil was pre-heated to 65°C and then the vacuum pump was turned on. The pressure and temperature were monitored every 15 minutes.
Oil samples were also obtained every 15 minutes from the sampling port near the surface of the oil. The moisture content of the oil was determined using the oven method. The quantity of the condensed water was also determined as indicated by the water level at the condensed water collector. The moisture content of the oil was computed based on this data by making water balance. The initial and final free fatty acid content were also determined.
Results showed that when the oil IS heated up to 100°C, 115°C, and 130°C, the equilibrium moisture contents obtained from water-balance method were 0.55% in 2.25 hours, 0.32% in 2 hours, and 0.11% in 2 hours, respectively, while from direct-sampling method, the values were 0.796%, 0.634%, and 0.22%, respectively. The evaporation rate 1 varying because the condition also varies. However, maximum drying rate values were 0.53 L/min·ft2 at 91°C in 33.1 minutes, 0.65 L/min·ft2 at 98°C in 36.2 minutes, and 0.68 L/min·ft2 at 97°C In 36.9 minutes, respectively. Also, when the oil is heated up to 130°C with initial moisture contents of 2%, 4%, and 6%, varying the initial moisture content has negligible effect on the equilibrium moisture content of the oil. Maximum drying rate values were 0.68 L/min.ft2 at 97°C in 36.9 minutes, 0.92 L/min.ft2 at 102°C in 47.8 minutes, and 1.30 L/min.ft2 at a range of 104-122°C in 45-75 minutes, respectively. Also, the free fatty acid content of the coconut oil was not significantly reduced.
Go back to Research Abstracts