A method of filtering contaminants from a fluid is disclosed. A feedstream of fluid containing contaminants is directed into a filter chamber containing a filter element. Part of the feedstream fluid flows in one of: a forward flow direction where it passes in a first direction through a wall of the filter element; and a reverse flow direction where it passes in a second, opposite direction through the wall. The filtrate is directed into a flowline for collection. The feedstream fluid is then arranged to flow through the filter element in the other direction, to remove contaminant material from a surface of the element wall. Following removal of contaminant material, the feedstream fluid is continued to be directed through the wall of the filter element in said other direction, to filter out contaminants from the fluid during flow in said other direction.

Methods and systems of harvesting a cell product from a cell culture by culturing cells in a fluid medium until the cells have produced a cell product at a harvest concentration are disclosed. The cells are cultured in a cell culture system including a bioreactor connected to an ATF device. The methods include draining fluid medium from the bioreactor through the outlet and the ATF device until the bioreactor volume reaches a predetermined volume, and the ATF column yields at an ATF outlet a liquid containing cell product and passes fluid medium with a concentration of cell product that is lower than the harvest concentration back into the bioreactor, extracting the liquid containing cell product from the ATF outlet, refilling the bioreactor with sterile phosphate buffered saline or fluid medium without any cell product, and repeating steps until a desired amount of cell product has been removed.

A method for cleaning a blood filter includes: (i) pumping a physiologically safe fluid back and fourth through the insides and/or the outsides of a plurality of hollow fiber membranes of the blood filter to remove or loosen blood residuals, such as blood clots, proteins and/or biological fluid; (ii) injecting air into the physiologically safe fluid to form an air/fluid mixture; (iii) pumping the air fluid mixture through the insides and/or outsides of the plurality of the hollow fiber membranes of the blood filter to further or remove or loosen blood residuals therefrom; and (iv) removing the air/physiologically safe fluid mixture along with the removed or loosened blood residuals to drain.

A reverse osmosis arrangement is described, the first chamber (5) having a first port (7) and a second port (8) and the second chamber (6) being connected to a permeate outlet (9), wherein the first port (7) is connected to a first pump (13). Such a reverse osmosis arrangement should be operated with high efficiency. To this end the second port (8) is connected to a second pump (14).

A filtration cell (10) for a biological sample including an upper chamber for receiving the biological sample to be filtered, a lower chamber in fluid communication with the upper chamber, and a filtration membrane (14) positioned between the upper chamber and the lower chamber is disclosed. A surface of the filtration membrane has a contact angle >90. The flow of the biological sample through the upper chamber may be tangential to the filtration membrane and a filtrate passing through the filtration membrane may be collected in the lower chamber. Also, a method of filtering a biological sample including passing the biological sample through an upper chamber of a filtration cell as described above and collecting a filtrate in the lower chamber is disclosed.

A membrane separation device includes a separation membrane unit A that has a separation membrane unit component 8, feed stream side lines F1 and F2, and a permeate stream line P, and a unit for feeding a stream-to-be-treated, wherein a stream-to-be-treated sealing material is provided in the perimeter of an anti-telescoping plate of the separation membrane element, wherein the separation membrane elements can be moved within a cylindrical pressure vessel substantially in either direction, wherein the separation membrane unit is configured to feed the stream-to-be-treated through one of the feed stream side lines F1 and F2 and to discharge the concentrate stream through the other of the feed stream side lines, and wherein the separation membrane unit includes a mechanism that can switch the flow between the feed stream side lines.

Disclosed herein are apparatuses and methods for semi-permeable membrane cleaning. In particular, a pressure retarded osmosis (PRO) process redirects raw solution and fluid streams in such a way as to cause periodic changes of the process from PRO to reverse osmosis (RO) for lifting and detaching fouling. Further disclosed is applying, at least periodically, a pulsed-flow regime in the fluid stream, thereby causing increased shearing force for enhanced evacuation of the foulant. Additionally, a backward wash may be provided by injection, for a predetermined injection time, of additional solution selected in such way that net driving pressure becomes RO opposite to normal PRO operation, thereby providing a backward flow from a first side of the membrane to a second side of the membrane, so as to lift and evacuate foulant.

The invention relates to a method for fouling reduction and/or fouling removal and/or prevention of fouling in membrane based fluid-flow processes, such as ED, RED, EDR, CDI, fuel cells, filtration, flow batteries, and a device capable of performing such methods. The method comprises the steps of: providing a dynamic membrane stack with a number of membranes, the stack capable of changing the average inter-membrane distance between two adjacent membranes with the inter-membrane distance being the distance between the membrane surfaces of two adjacent membranes; performing the membrane based fluid-flow process in a first state with the stack having a first set of average inter-membrane distances; switching the membrane based fluid-flow process between the first state and a second state wherein the stack having a second set of average inter-membrane distances different from the first set; and performing the membrane based fluid-flow process in the second state, wherein, at least in an initiating phase, fouling is removed and/or reduced and/or prevented.

An isolation device includes an isolation chip assembly, a vacuum system, a frequency converting module, and a controller. The isolation chip assembly includes an isolation chip having a first chamber and a second chamber, a first oscillator mounted on the first chamber, and a second oscillator mounted on the second chamber. The frequency converting module causes the vacuum system to generate negative pressure in the first and the second chambers alternately. The controller controls the first and the second oscillators to operate when the vacuum system stops generating the negative pressure in the first chamber and in the second chamber. The first and the second oscillators respectively generate a first and a second oscillation wave when operating, a frequency of the first oscillation wave is greater than a frequency of the oscillation wave, an amplitude of the first oscillation wave is less than an amplitude of the second oscillation wave.

Disclosed herein are apparatuses and methods for semi-permeable membrane cleaning. Specifically, a pressure retarded osmosis (PRO) process redirects raw solution and fluid streams in such a way as to cause periodic changes of the process from PRO to reverse osmosis (RO) for removing fouling. Further disclosed is applying a pulsed-flow regime in the fluid stream, thereby causing increased shearing force for enhanced foulant evacuation. Additionally, a backward wash may be provided by injection of additional solution such that net driving pressure becomes RO as opposed to PRO, thereby providing a backward flow from a first side of the membrane to a second side. Further disclosed are phased operations that resolve the issue of self-extinguishing PRO, thereby providing energy savings and/or PRO process optimization by, for instance, (1) utilizing osmotic pressure for circulation, (2) variation in POp gauge pressure, and/or (3) variation of the ratio of Additional Solution to Draw Solution.