GB442081A - An improved method of separating contamination from lubricating oil - Google Patents

Abstract

<PICT:0442081/III/1> <PICT:0442081/III/2> In a process for regenerating used lubricating-oils, such as from internal combustion engines, the used oil is passed through a filter F, Fig. 1, and flows through a pipe p<3> to a still S from which diluent fuel vapours are drawn by a pump through a condenser C<1> and the condensate flows into a receiver FR. The regenerated oil flows through a pipe t into a reservoir OR, the top of which together with fuel receiver FR is connected to a vacuum pump VP. The filter F may also be connected to the vacuum pump. The still S consists of a series of superposed members a<1>--a<4>, Fig. 2, each having a central opening an extending above a circular annular well ar, at the base of which is a drain tube connected to the well of the member below. A vertical plate having holes at the bottom is mounted in front of each drain tube to retain any froth. The lowest member a<1> forms a sump for oil and is provided with an overflow pipe t. The cover member a<5> contains a vapour outlet v, a safety valve s, and a thermostat t<9>. The members are heated by electrical resistances e to a temperature of 300 to 500 DEG F., and the whole apparatus is mounted within a casing c. In operation, the filtered oil is fed upwards through a pipe p<3> to the top member a<4>, and flows around the recess to the outlet pipe through which it descends to the next member a<3> in the series and finally into the sump a<1>. During the downward flow, the diluent fuel is vaporized and passes through the central apertures to the outlet v. The regenerated lubricating oil flows from the sump through the pipe t to the reservoir. The members a<1>--a<4> are shaped so that a large cross-section of metal is provided through which heat flows, the cross-section decreasing towards the centre. Heating may be effected by superheated steam.