Improving the solvent-extraction process of rice bran oil

Abstract

Extracting crude oil from oilseeds is the first step in the production of vegetable oil. Organic solvent-extraction is widely applied. The production of high value rice bran oil is gaining increased interest, and is the subject of the present paper. Field data from a 32T/day pilot plant in Heilongjiang will be compared with engineering simulations. Since these processes are energy-intensive, two strategies for saving energy in the process will be assessed. Field data and simulation results will be shown to be in excellent agreement. Two energy optimization strategies were designed by both energy pinch technology to integrate heat recovery, and by using nitrogen instead of steam in the desolventizer/toaster, subsequently using a solvent recovery unit with gas membrane. As a result, 45.2% of the total energy consumption of the rice bran oil process can be saved whilst maintaining the original production capacity and high purity of the crude rice bran oil. The results confirm the possible energy savings and improvements in the solvent extraction process. It is also noteworthy that simulation techniques, commonly used in gas/liquid chemical engineering design, can be adapted and completed to cover the more complex design of solid/gas/liquid biochemical processes.