Patent GB-654036-A (GB)
Title: Improved method and apparatus for the extraction of oils from vegetable matter such as seeds, nuts and beans
IPC: C11B1/10
Filed: 1948-11-01
Abstract: <PICT:0654036/III/1> Fatty oils are extracted from vegetable matter, such as nuts, beans and seeds, by thoroughly mixing together the pulverized raw material and an extraction solvent to form a slurry, and then conveying the slurry through a number of contiguous zones of differential pressure wherein it is successively subjected to suction, to agitation by means of a forced draught and to extraction with further solvent.  The fluid content of the slurry is recovered at the suction zones from which the fatty oil and solvent may be separately recovered by distillation, and the caking of the solids in the slurry induced by the vacuum is resolved by the succeeding pressure agitation zones, the opened-up material being ready for the following re-extractions with fresh solvent.  The slurry may be conveyed through the zones as a series of contiguous pools, and the solvent at any stage may be replaced by a miscella arising at any point.  In a preferred apparatus, an enclosed casing 5 has entry ports 3, 19 for slurry and solvent respectively, an exit port 6 for spent material, and a compartment 13 partitioned into a number of sections, such as a to f, with a selected number thereof, such as b, c, e, f, having reticulated tops 15, 16, and means for establishing therein differential pressure in successive sections, and also a series of contiguous chambers 12 having reticulated bottoms constituted by a continuous belt conveyer 10 arranged so as to travel in close proximity to the top of the compartment 13.  In the apparatus shown, sections a, d of the compartment 13 have solid tops 14, sections b, e are provided with vacuum means 17, and sections c, f with pressure-developing means 18.  The belt conveyer 10 circumscribes the partitioned compartment 13 and is of the same width as the enclosed casing 5, the sides of which constitute the side walls of the contiguous chambers 12, the division walls of the contiguous chambers comprising division plates 11 projecting at right angles from the conveyer and each preferably consisting of a spring-loaded shutter 11a bearing resiliently against the sides and upper surface of the enclosed casing.  The entry port 3 for the slurry discharges from an enclosed trough 1 having a feed-hopper 2 for the pulverized vegetable material and a valve-controlled inlet 7 for the solvent or miscella, the mixture being moved through the trough by a paddle form of conveyer blades working between beater-arms within the trough which create a consistent slurry of the mixed materials.  The discharge hopper 6 has a lip 20 extending across the width of the enclosed casing 5 to isolate therefrom any leaking slurry which may be removed through a discharge-pipe 21.  In operation, the slurry from the entry port 3 fills one of the contiguous chambers 12 on the porous belt 10 lying above the section a of the partitioned compartment 13, and with the movement of the belt passes over the perforated top sections b and c.  The fluid content is removed in b and the p  caked material is opened out above the section c.  The chamber 12 is then brought over the neutral section d where it is re-extracted with solvent or miscella through port 19.  The cycle is then repeated through sections e, f, and any further number of sections corresponding to a, b, c, or d, e, f, the chamber 12 of spent meal then moving over to the discharge hopper 6. The air withdrawn from the zones in which the slurry is subjected to suction may be used to boost the pressure obtaining in the sections in which the slurry is subjected to pressure agitation. The slurry may be pre-heated in the enclosed trough 1 by suitable jacketing of the trough.