Pilot-plant application of filtration-extraction to rice bran.

The pilot-plant application to rice bran of a recently developed method of solvent extraction, called filtration-extraction, has been described. The process consists simply of mildly cooking the rice bran, cooling to about 130° F., slurrying the cooked bran with a miscella filtrate, filtering the slurry and countercurrently washing the cake three times on a continuous, rotary, vacuum filter, followed by conventional recovery of oil and meal products. The advantageous effects of cooking under the conditions described in the paper are reflected in the shorter filtration cycle time, better extractability, and virtual elimination of the fines problem. For example, tests showed that uncooked bran required filtration cycle times of more than 30 minutes compared to 30 to 60 seconds for cooked bran. This development makes available to the industry a feasible continuous solvent-extraction process for rice bran. Feasibility of the process is due primarily to the practical elimination of the inherently serious fines problem and to other advantages of the process, such as the possibility of attaining high capacities for small units; lower solvent content of extracted cake and of final miscella, which should decrease recovery costs; lower solvent requirements; and extraction to a residual lipides of 1 to 1.5%. Because of the reduced equipment size and simplicity of the process, it should prove economically feasible for the small and medium-sized plant, where heretofore a solvent-extraction plant required the processing of relatively large quantities of material daily. [ABSTRACT FROM AUTHOR]