Abstract: A two-piece body high pressure membrane test cell is disclosed with a tangential feed into the interior pressure chamber in which a central distributor element is mounted with the lower frusto-conical end thereof at a critical spacing above a filter membrane. The membrane is supported on an annular land of a filter support disc which has a peripheral edge zone compressed in a sealed fit between the lower and upper pieces of the cell body. The edge zone is machined to a precise thickness to provide a reproducible and accurate spacing between the filter membrane that rests on the support and the lower end of the distributor.

Abstract: A pressure filtration cell includes a reservoir for liquid to be filtered, a filter at the bottom of the reservoir, and a manually actuable pump for supplying compressed air. The pump is detachable from the reservoir. The air is introduced near the bottom of the reservoir closely adjacent the filter so as to create turbulence in the liquid and across the filter. The turbulence is of a pulsating nature due to the intermittent operation of the pump. Thus, the pump is easily portable for use anywhere and creates a "dynamic" filtration process even without a mechanical stirrer. If used in a laboratory, the cell can be provided with a rotary, magnetically operated stirrer mounted on a relatively short axle.

Abstract: A compensating plate for a pressure filtration cell including a generally cylindrical liquid-feeding vessel and a base removably connected to the feeding vessel by means of a flanged joint, the removable base forming a filter holder, in which an outer edge of the plate is engaged in a flange between the liquid-feeding vessel and the filter holder and, on its upper side, the outer edge of the plate is sealed against the liquid-feeding vessel by means of a circumferential seal. The compensating plate has a central opening corresponding to the size of a filter placed in the filter holder, the plate having a slight conical depression toward the said opening.

Abstract: A syringe of the slide piston pump type is adapted to overcome a pressure resistance at its outlet as may be provided, for instance, by a filter in communication with the outlet and through which the syringe is to pump a medium, particularly a liquid medium, for filtration. The syringe comprises a cylinder containing a piston, and a piston rod. The piston rod is fixed to a second piston sliding within a longitudinal bore in the first-mentioned piston. The bore and the second piston cooperate to define an air-filled pressure chamber connected to a cylinder chamber, defined by the first piston and the cylinder, by a valve. Inward movement of the piston rod produces an over-pressure (e.g. 16 atmospheres) in the pressure chamber to open the valve to apply the over-pressure to the liquid or other medium in the cylinder chamber to overcome the pressure resistance of the filter and enable the liquid to be forced through the filter.