GB771492A - Improvements in or relating to degreasing processes and apparatus - Google Patents

Abstract

<PICT:0771492/III/1> <PICT:0771492/III/2> In a process wherein textiles are degreased with a solvent and subsequently dried, the dust being removed by air circulation, the degreasing is effected with a small amount of solvent sufficient only to dissolve the grease in the material being cleaned and thus unable to remove the dust, and most of the drying is carried out thermally, without solvent removal by centrifugation, the heat required for the drying being supplied by a heat supply distinct from the dust-withdrawing air. In a suitable plant, the cleaning apparatus comprises a rotatable perforated drum 7 within a fixed container 2 to which the solvent is supplied, a reservoir 21 for the used solvent connected through a liquid control chamber 24 to the container 2, and a pump 27 for forcing the used solvent through a filter 30 for return to the container 2 through a pipe 64. The perforated drum 7 is given an oscillating movement during the cleaning step and its contents may be rinsed by purified solvent from the filter 30. The perforated drum 7 is provided with heating pipes or a coil 20 integral therewith and is supplied through its supporting shafts with steam for the drying step or with cold water in a final cooling step. Steam is also supplied to the container 2 through inlets 5 and 6. After the cleansing step, steam is admitted to the container and also to the heating pipes 20 on the drum 7, which latter is further oscillated. A compressor 31 is then started to remove the solvent vapours and supply them to a condenser 33, from which purified air is then fed to the container 2 through a pipe 34 for removing dust from the dried materials being cleaned. The filter is of known type comprising two concentric vertical filtering membranes which may be vibrated. The condenser 33 contains a baffle arrangement to impart a cyclone action to the vapour laden air. The used solvent may be diverted to a still 50.