GB491106A - Method of and apparatus for comminuting and extracting materials, in particular oil seeds - Google Patents

Abstract

<PICT:0491106/III/1> <PICT:0491106/III/2> <PICT:0491106/III/3> Oil seeds, fruit, beetroot, and similar materials are comminuted and extracted by pressing the raw material in a pressure worm, with solvent if desired, to form a coherent mass of rope-like form which is then comminuted and spread in a thin layer with additional solvent if necessary, upon a travelling filter band through which the extract passes. A pressure worm 2, Fig. 1, has threads 3 of uniform diameter mounted on a core 4 which increases in diameter from a point 5 to the outlet, where the threads run into the core. The casing 1 also increases in size at 6 towards the outlet whereby the interspace between the core and casing remains constant. The inner wall of the casing is provided with longitudinal ribs 7 forming internal grooves 8 open towards the worm, and each enlarging in cross-sectional area towards the outlet to form ultimately a circular opening in a closing disc 9. Spring-pressed against this disc 9 is a disc 12 provided with cutting blades 13. A solvent such as gasoline, is supplied through nozzles 18 and 19. In operation, seed enters a hopper 20 and is pressed to form a series of ropes passing through the disc 9, where they are cut off by the disc 12. The degree of comminution may be varied by adjusting the speed of the cutter. In a modification, the internal grooves 8, Fig. 10 (shewing a cross-section of Fig. 1 at LM), are provided with small channels 22 and sieves 23 mounted in front thereof whereby a greater compression of the raw material is obtained, and expressed oil and solvent passes through the channels to an outlet 21. The comminuted material mixed with solvent passes through an opening 24, Fig. 2, to a filter band 25, travelling in a gas-tight enclosure, between roll presses 27, 27a, 27b, and over a heated drum 28. The filter band consists of a cloth fabric of 2000 mesh per square cm., or a twilled bronze fabric having silk or wool threads woven therein. The roll presses 27 . . 27b are provided on the surface with conical run-off slots, and the pressure is regulated by weights 30 . . . 30b. The layer of material is disturbed between each roll press by rotating rakes 36, and solvent is sprayed thereon through distributers 37. Filtered oil and solvent flows into collecting pans 29 . . . 29b, and then into pans 35 . . . . 35b. Expressed oil and solvent passes through the conical slots in the lower roll press 27 . . . . 27b and collects in a receiving pan mounted therein from which it flows to pans 35 . . . 35b. The weak solution from pan 35b is used to spray the comminuted material on the filter band, the solution from the pan 35a is used in the comminuting apparatus Z, and the concentrated solution in the pan 35 is distilled to recover the oil. The filter band returns from the last roll press 27b through a scraper 46, which removes the exhausted material, and through a solvent spray 39 to the heated drum 28, which is separated by a wall 40 from the remainder of the enclosure. The process may be used for the extraction of soya beans, copra, rape seed, earthnuts, palm kernels, beetroot or apples.