GB588896A - Improvements in and relating to the treatment of wool-washing effluent - Google Patents

Abstract

<PICT:0588896/III/1> The effluent from a wool-washing plant is concentrated by evaporation until it contains 4 per cent. or more of wool fat, then heat treated by circulating it between a heater and an autoclave until a temperature of 290 to 302 DEG F. at a pressure of 50 lbs per square inch is reached, and it is then allowed to settle in the autoclave so as to separate wool-fat, clear aqueous liquor, and muddy liquor from one another. The separated layers may be run off and collected separately. The effluent may be circulated from the bottom of the autoclave chamber to the inlet end of the heating device and from the outlet end of the heating device to the top of the autoclave chamber. One steam or other heater may be used for heating the contents of a number of different autoclaves in succession. As shown in Fig. 2, effluent from the wool washery, after preliminary evaporation to give a concentration of 4 per cent. or more of wool fat is admitted through pump 7 and pipe 9 to the lower manifold 14 of heater 1. The effluent passes through steam-heated pipes within the heater 1 and from the upper manifold 14 and pipe 16 to the upper portion of one of several autoclaves 2, 4, which may be operated separately and in succession by means of appropriate connections and valves. The effluent is circulated down through the autoclave 2 and thence through outlet 26, distribution piece 30 and pipe 37 to the pump 7. The effluent is thus maintained in circulation until the whole body of effluent in the heater is raised to the temperature and pressure desired. The autoclave 2 is then cut off from the heater 1, and the effluent is allowed to settle. A further quantity of effluent is passed into another autoclave and treated in a similar manner, while the effluent in autoclave 2 is settling. The mud is drawn off through valve 36, pipe 37, and pump 7, which discharges the mud through pipe 41. The clear aqueous liquor is then removed by closing valve 36, opening valve 36a, and running the liquor through pipe 35, back to a wool washing plant for re-use. The wool-fat is removed by closing valves 36, 36a, and opening valve 34. To prevent bubbling or turbulence of the contents of the autoclave 2 when the constituents are being removed after settling, steam or air may be admitted to the top of the autoclave by appropriate pipes and valves.