GB917638A - Process and apparatus for rendering oils and fats from solid oil-bearing materials - Google Patents

Abstract

A process for rendering fats and oils from solid oil-bearing materials, for example fallen animal carcasses, butchers' scraps, offal, condemned carcasses, oil bearing fish, or fish offal, comprises (a) pre-crushing solid oil-bearing material, (b) passing the crushed material through a first heat exchanger provided with means for conveying the material continuously therethrough, in which the material is subjected to a preliminary heat treatment, (c) passing the material through a disintegrator for further reduction of the material, (d) passing the material through a second heat exchanger also provided with means for conveying the material continuously therethrough, and (e) passing the material through a press in which the fats and oils in the cells of the material ruptured in the disintegrator are expressed from the material. As shown, a preferred embodiment comprises a conveyer 5 to which is fed solid material from pre-breaker 4, or soft material which has been hashed in hasher 2 and conveyed by conveyer 1 to washer 3 before passing to conveyer 5; the material to be extracted then passes to conveyer 6 whence it passes through port 8 into bins 7 and thence through valve 9 to conveyer 10. The material to be extracted <PICT:0917638/III/1> then passes through port 11 into heat exchanger 13, water also being fed in through port 12 as indicated by dotted lines 16. Heat exchanger 13 comprises a jacketed trough 17 in which a hollow heated screw conveyer 18 is rotated by means of a variable speed drive. The heated material leaves through port 21 and passes to disintegrator 23, in which the material is reduced to a size suitable for treatment in press 24. Water, fats and oils expressed therein pass through vibratory screen 25 to separator 27, from which fat is removed through 28 and passes by line 29 to settling tank 30, thence in turn to decanter 31, to tank 32 containing acid, and finally to polisher 33. Water from separator 27 passes by line 34 to tank 35, and is then returned by pump 14 and line 16 to heat exchanger 13. Solid material from press 24 passes through port 37 to second heat exchanger 36 of similar type to the first. The material passes therefrom to press 43, the expressed fats, oil and water passing through vibratory screen 44 to separator 46, the fat and water being separated as with separator 27 and treated similarly. Solid material from press 43 passes to disintegrator 51, and then through sealing valve 52 to sterilizer 54, whence it passes through sealing valve 57 to drier 59, and finally to disintegrator 64 leading to a sack filling and weighing machine 65. Specifications 883,051 and 908,381 are referred to.