VAETSKEREGLERINGSANORDNING FOER KROMATOGRAFISKA FRAKTIONERINGSKOLONNER

1403382 Liquid level control SUOMEN SOKERI OSAKEYHTIO 17 July 1972 [1 Oct 1971] 33328/72 Heading B1H [Also in Division Gl] Flow control apparatus for a chromatographic fractionating column includes a liquidpervious plate assembly adapted to float on the liquid layer overlying an ion-exchange resin bed within the column and a detection device carried by the assembly responsive to the thickness of the liquid layer reaching a predetermined minimum for opening a normallyclosed valve to supply additional liquid to the column so as always to maintain a liquid cover over the beds independently of whether the upper surface of the bed moves vertically within the column. As shown a plate 18 which may be of polystyrene is perforated with holes 28 to allow indirect access of liquid from nozzles 16 to bed 12 of ion exchange resin. A mesh 26 carried below the plate enters the bed when the plate is at its lowest position and ensures a smooth surface. Detector 30 is responsive to the thickness of the liquid layer and operates valve 34.