GB775003A - Improvements in or relating to a method of and apparatus for treating fat-containingmaterial - Google Patents

Abstract

<PICT:0775003/III/1> Raw natural animal fat and collargen containing material such as bones for gluemaking, is treated to remove fat therefrom by crushing the material into fragments and then centrifuging it whilst maintaining it at a temperature above the melting point of the fat but below the boiling point of water and in the presence of steam and water flowing through the centrifuge 1, the initial material being thereby separated into two phases viz., a residual degreased material and a fat-containing liquor. Other materials treated may comprise hides, suet, gut fat and meat. The material may be pre-heated under the above temperature conditions before being crushed, and it may be re-heated prior to or whilst being centrifuged. The temperature range is preferably 140 DEG to 190 DEG F. The preheating is preferably rapid and, after the centrifuging, the degreased material is preferably rapidly cooled, e.g. by introducing cold water into the centrifuge. In a suitable plant for degreasing bones for glue making, the material is conveyed from a storage 1 to distributer 7 on to a sorting belt 15 thence to a pre-heater 19 from which it is passed to vibrator 26, to separate any liquid fat, before being fed to a double crusher mill 38. The crushed material is then conveyed to centrifuger 52 and the separated degreased material is dried in a dryer 68 and sifted in a unit 83 to remove small particles, the material then being ready for glue-making. The fat liquor from the vibrator and centrifuger is led off through channel 35 and separated into fat and an organic liquid. The preheater 19 may be a rotary chamber having an internal perforated steam pipe. The double crusher mill comprises an upper and a lower rotating cylinder furnished with double ended knives. The crushed material is conveyed by trolleys with centrifuge baskets 48 running on an endless track. Lifting arms 54, 55 convey a filled basket to a centrifuge and remove it respectively. In the latter operation the degreased material is emptied into a hopper 57 of a screw conveyer 58 for conveyance to the dryer 68. The centrifuges are provided with inlet nozzles for supply of steam, hot or cold water or air. Preferably steam is supplied to the centrifuge for degreasing step, followed by hot water, and the effluent is removed. Cold water is then supplied to cool the degreased material, which is then dried. The dryer may be internally heated by hot air.