Separation unit comprising a device for controlling the flow of at least one fluid

摘要

The column (1) contains a number of trays in closed loop with a fluid recirculator (9), at least two fluid injection lines under flow control and at least two fluid extraction lines. One extraction line is under flow control. The other is pressure controlled by a control valve (6) and contains at least one restriction (201) so the pressure can be lowered downstream of at least one of the trays A number of trays are arranged in closed loop in at least one chromatographic column. The pressure controlled extraction line contains at least one restriction so the pressure can be reduced between at least one of the trays and the pressure control valve, or it contains several restrictions in parallel or series to maintain the pressure upstream of the valve at a set level. The pressure controlled extraction line contains the refined product. At least one of the injection lines includes a flow control valve (13) and at least one restriction between the downstream side of the valve and at least one tray to maintain the pressure downstream of the valve at a set level. Control process using this regulator, where a pressure loss is established at at least one restriction and preferably several restrictions in parallel or series, on an extraction line, to obtain a pressure upstream of the valve between the lower extraction pressure PO and the value PO augmented by a fraction of the pressure loss in the column, preferably at most to PO plus 50% of the pressure loss in the column or PO plus 10% of the pressure loss in the column.