| 摘要 |
PURPOSE:To achieve a higher separation accuracy by arranging an effluent discharge tube, a liquid level detector and a plurality of interface detectors each having a flow rate adjustor at the bottom and top of a filling column and on the side thereof to keep a thickness of a liquid holding layer constant. CONSTITUTION:A plurality of interface detectors 18 are disposed on the side of a filling column 1 at a fixed interval and as the boundary between a filling layer 2 and a liquid holding layer 3 varies, a digital signal is outputted from the element 18 adjoining on the layer 2 to be converted into an electrical signal I1 with a controller 8. In a current generator 10, a value of a thickness to be held by the layer 3 is set to be outputted to an addition operator 11 as electrical signal II, which is added to the signal I1 inputted to be outputted to an adjustor 12 as electrical signal I3. By a liquid level detector 5, an electrical signal corresponding to a liquid level-to-level distance between a liquid level detector 27 preset and the layer 3 is outputted according to a change in a liquid level to be outputted to the adjustor 12 as signal I4. Thus, the adjustor 12 sends a difference I between the signals I3 and I4 to a flow rate controller 6 and a flow rate adjustor 7 to regulate a pump adjusting valve, thereby keeping a thickness of the liquid holding layer 3 constant. |
