Patent GB-618780-A (GB)
Title: Improvements in or relating to the extraction of oil from nuts, seeds and the like
IPC: C11B1/10
Filed: 1946-05-08
Abstract: In the extraction of oils and fats from solid material, the latter travels upwardly or downwardly in a sinuous path while a solvent is applied to the material at an <PICT:0618780/III/1> <PICT:0618780/III/2> <PICT:0618780/III/3> <PICT:0618780/III/4> upper level and drains downwardly through the material.  The material as it passes along individual legs or runs of the sinuous path is subjected several times at intervals to floodings with solvent.  The solvent may be passed countercurrent to the material to be extracted.  The apparatus in which the extraction is carried out, may comprise vertically spaced trays or partitions, a conveyer through which the solvent can drain, arranged to travel in a sinuous path along and between the trays or partitions, means for feeding material to be treated on to the conveyer, means for discharging the material after treatment, means spaced along the conveyer for flooding or drenching the material with solvent and means for subsequently discharging or collecting the solvent. There may be intervals for drainage between the flooding of the material with solvent, and the conveyer may have drainage means for the drainage of the solvent through it and on to the tray below.  The trays may be apertured or in spaced sections so that the solvent runs from a tray above on to the material on the section of the conveyer below.  The supply means for solvent, material to be treated, discharge means for the treated material and solvent containing the extracted matter, and the conveyer are arranged so that the solvent flows downwardly from one section of the conveyer to a section below countercurrent to the upward movement of the conveyer.  The feeding means for the material to be treated may be provided with a control valve or shutter which is connected with the conveyer mechanism so as to be operated in synchronism with the movement thereof and so as to be opened as a conveyer bucket comes beneath said feeding means and closed during the passage of a gap between neighbouring buckets beneath the feeding means.  Means may be provided for collecting sludge from the base of the apparatus and returning it to the conveyer buckets.  As shown, crushed nuts or seeds to be extracted are fed by means of a shoot 21 (Figs. 2 and 5) in the top of the tall closed casing 10 (Figs. 1 and 3) into the long conveyer buckets 15 (Figs. 1, 2 and 5) as they pass below it.  The discharge of material from the shoot is controlled by valve shutters 21a (Fig. 5) which are opened for a period as each conveyer bucket comes into position below the shoot.  The shutters are operated synchronously with the movement of the conveyer by a cam-wheel 21b (Fig. 5) keyed on the shaft 19a (Figs. 2 and 5) carrying one pair of the conveyer sprocketwheels.  The cam members 21c of the camwheel 21b operate one of the shutters 21a through an arm 21d carrying a cam roller 21e.  The other shutter carrying the closing weight 21f is operated by gearing it to the arm 21d through toothed segments 21g. After being filled with material from the shoot 21, the buckets 15 attached to the conveyer belt 11 (Figs. 1 and 2) comprising a pair of endless-chains 14 (Figs. 1 and 2) between which the buckets are supported in such a manner as to swing freely, pass vertically downwards to the lower part of the machine and then follow a sinuous path upwards and between a number of inclined trays 12 (Figs. 1 and 2) spaced one above the other, the chains 14 being guided by roller 16 (Figs. 1 and 3) running in tracks 17 (Figs. 1 and 3) on opposite sides of the trays.  As the buckets pass above and along the uppermost tray their contents are flooded with solvent from the perforated pipes 27 (Figs. 1, 2 and 3) spaced comparatively far apart.  The solvent, now containing matter extracted from the material in the buckets drains out through the perforated bottoms of the buckets on to the tray beneath, runs down the tray until it reaches one of the spaced successive gaps 13 (Fig. 1) in the tray then flows through the gap on to the material in the moving buckets immediately below.  The solvent passes similarly from tray to tray via the buckets of material, extracting more and more matter from the material as it flows downwardly countercurrent to the path of the buckets.  Finally, the solvent runs on to and down the false bottom 12a (Figs. 1 and 2) and floods into the sump 10a (Fig. 2) from whence it is discharged.  After passing beyond the uppermost tray, the buckets are tipped by means of the cam elements 23 and 24 (Fig. 1) and discharge the spent material into the hopper 22 (Figs. 1 and 3) from which a worm 25 (Figs. 1 and 3) feeds the material to and through a discharge duct 26 (Figs. 1 and 3).  A chain scraper 31 (Figs. 1 and 2) driven from one of the sprocket-wheel shafts 19 (Fig. 1) scrapes the sludge settling on the bottom of the casing to one end, from where it can be returned to the conveyer buckets via pipe 27a (Fig. 1).  The machine may be provided with ten trays each having an average of, say, four spaced solvent discharge gaps or slots, the material thus being subjected to a large number of alternate floodings and drainings during its passage through the extractor.