GB805547A - Method and apparatus for extracting contaminants from a liquid-permeable body - Google Patents

Abstract

<PICT:0805547/III/1> In a process and apparatus for extracting contaminants from a liquid-permeable solid body (e.g. an oil-well core) the body 19 is immersed in an extracting liquid 21, e.g. water, or toluene, pentane, &c. with an emulsifier, which is subjected to ultrasonic waves from a vibrator 16 whilst the extracting liquid is simultaneously cyclically caused to boil by reduction of pressure and cease boiling by an increase of pressure. The body may be preheated before immersion. Container 13 is closed by a transparent cover 24 having conduit 27, 28 leading to suction pump 29 and air valve 30 which may be hand controlled or auto-electrically controlled via the optional system 40, 56, 57. In the former case, the valve head 31 raised as shown, the suction pump is started and reduces the pressure in vessel 13 until the extracting liquid 21 is seen through cover 24 to boil, when handle 35 is depressed to lower head 31 on to seat 38, thus cutting off the suction pump and placing the vessel in communication, via passage 33 with the ambient air so stopping the boiling. Handle 35 is raised and the cycle repeated, the magneto-strictive transducer 16 throughout supplying ultrasonic vibrations of say 15-60 k.c.p.s. via container 13 to the liquid 21, mesh carrier 18 and cores 19. For automatic cyclic control the diaphragm system 40, solenoid 56 and timer 57 are employed. Upon the pressure in 13 being reduced by pump 29 to a pre-determined value, diaphragm 47 moves down against spring 46, causing collar 52 to close contacts 54 and operate solenoid 56 to close valve 30 for a period determined by a timer 57 actuated via switch 58 and electric supply 59. Specification 797,417, [Group II], is referred to.