GB366969A - Improved method of extracting oil and other by-products from ground nut sludge - Google Patents

Abstract

Oil, albuminous matter, and nitrogenous fertilizers are obtained from the putty-like mass remaining on the cloths when crude pressed peanut oil is filtered, by mixing with caustic alkali solution, boiling with alkali chloride solution, removing the oil layer, separating the solid residue for use as a fertilizer, treating the remaining liquid with acid to precipitate casein, filtering, and precipitating an inferior albuminous matter by "aluminoferric" or the like; the remaining solution may be used for treating subsequent batches of material or for the recovery of salts. The casein and albuminous matters may be used in the manufacture of cold water glue, sizes, and distempers. In an example, 100 lb. of the putty-like mass is mechanically mixed with 30 lb. of 30 per cent caustic soda, and allowed to react for 30 minutes; the mass is then boiled with 7 vol. of 5-10 per cent sodium chloride for 30 minutes and allowed to settle; the oil is skimmed off, and the aqueous solution withdrawn leaving the insoluble manurial matter. The solution is centrifuged to remove traces of oil, acidified by hydrochloric or sulphuric acid, and filtered to remove precipitated casein; the filtrate is then treated with a crude mixture of sulphates of iron and alumina to precipitate the remaining albuminous matter. The casein is washed with water and then dried at 120 DEG C. or below.ALSO:The residue from the filtration of crude pressed peanut oil is mixed with caustic alkali solution and boiled with alkali chloride solution, the oil layer is removed, the solid residue separated, and the remaining liquid treated with acid to precipitate casein; after filtering, an inferior albuminous matter is precipitated by "alumino-ferric" or the like; the remaining solution may be used for treating subsequent batches of material or for the recovery of salts. In an example, the filtration residue is mechanically mixed with caustic soda solution and allowed to react for 30 minutes; the mass is then boiled with sodium chloride solution for 30 minutes and allowed to settle; the oil is skimmed off, and the aqueous solution withdrawn. The solution is centrifuged to remove traces of oil, acidified by hydrochloric or sulphuric acid, and filtered to remove precipitated casein; the filtrate is then treated with a crude mixture of sulphates of iron and aluminium to precipitate the remaining albuminous matter. The casein is washed with water and then dried at 120 DEG C. or below.ALSO:A solid nitrogenous residue, suitable for use as fertilizer, is obtained from the putty-like mass remaining on the cloths when crude pressed peanut oil is filtered, by mixing with caustic alkali solution, boiling with alkali chloride solution, and removing the oil layer.