An ocean alkalinity enhancement (OAE) system that reduces atmospheric CO.sub.2 and mitigates ocean acidification by electrochemically processing feedstock solution (e.g., seawater or brine) to generate an alkalinity product that is then supplied to the ocean. The OAE system includes a base-generating device and a control circuit disposed within a modular system housing deployed near a salt feedstock. The base-generating device (e.g., a bipolar electrodialysis (BPED) system) generates a base substance that is then used to generate the ocean alkalinity product. The control circuit controls the base-generating device such that the alkalinity product is supplied to the ocean only when (1) sufficient low/zero-carbon electricity is available, (2) it is safe to operate the base-generating device, and (3) supplying the alkalinity product will not endanger sea life. Modified BPED systems include features that facilitate autonomous system operations including enhanced maintenance cycle operations and a reduced reliance on external fresh water sources.

Processes and systems for filtering a liquid sample are provided. Batches of a liquid sample can be routed to two or more cycling tanks (e.g., first and second cycling tanks). Upon filling a first cycling tank, a first batch of the liquid sample can be routed to a filtration assembly by a continuous diafiltration process that includes routing produced retentate back to the first cycling tank or to a collection vessel. Upon filling a second cycling tank, a second batch of the liquid sample is routed to the filtration assembly by a continuous diafiltration process that includes routing produced retentate back to the second cycling tank or to the collection vessel. The filling and continuous diafiltration of batches of the liquid sample continues to alternate between the two or more cycling tanks until a total product volume is processed.

A filter module (10) has a housing (12) which is subdivided by a membrane filter (14) into an inlet chamber (16), which is connected to an inlet connecting piece (22) arranged rigidly on the housing (12), and an outlet chamber (18), which has a filtrate outlet (20). The inlet connecting piece has two connectors, specifically a first connector (26) and a second connector (28), which connect selectively and fluidically to the inlet chamber with a 3-way valve (24) integrated into the inlet connecting piece. The valve has a first entry, which is connected to the first connector, a second entry, which is connected to the second connector, and an exit, which is connected to the inlet chamber. The first connector is configured as an adapter for outwardly sealed coupling of a culture medium bottle (30), which coupling permits a gravity-driven exchange of liquid with the first entry of the valve.

A potable water filter for an aircraft galley plumbing system is disclosed. In embodiments, the filter includes a body attachable to a mount via a central threaded attachment stud. The stud is surrounded by a filter mount chamber and encloses a central flow channel allowing outflow from the filter body to an outlet port. Potable water enters the mount through an inlet port; an annular “puck” inlet valve extends around the attachment stud, sealing off the filter mount chamber when the filter body is absent and, when the filter body is screwed onto the attachment stud, providing for water flow throughout the filter mount chamber. The filter body houses a solid block of sintered carbon with a hollow core. Water enters the filter chamber via bypass slots in the base of the filter body and flows around and through the carbon filter before flowing down to the outlet port.

A method of operating a dual reverse osmosis/pressure retarded osmosis plant, including when electricity costs less than a first predetermined price, moderate salinity water is pumped into the first portion of a pressure vessel having first and second portions separated by a water permeable/salt impermeable osmotic membrane to yield desalinated permeate in the second portion and brine in the first portion. Further, when electricity costs greater than the first predetermined price, low salinity water is pumped into the second portion and brine is pumped into the first portion to yield pressurized moderate salinity water in the second portion which is run through an energy recovery device to generate electricity. The salinity of the low salinity water is lower than the salinity of the moderate salinity water, and the salinity of the moderate salinity water is lower than the salinity of the brine.

Systems and methods for filtering materials from biologic fluids are discussed. Embodiments may be used to filter cerebrospinal fluid (CSF) from a human or animal subject. In an example, CSF is separated into a permeate and retentate using a tangential flow filter. The retentate is filtered again and then returned to the subject with the permeate. During operation of the system, various parameters may be modified, such as flow rate and waste rate.

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 reject valve of a reverse osmosis device, which is especially suited for brackish water reverse osmosis devices, which require a low system pressure less than 15bar. The valve keeps the system pressure substantially constant in a pre-defined range of the reject volume. The size of the inflow channel is adjusted by a spring-operated cone, which never entirely closes the channel, which forms a constant throttle until the pressure of the inflow has risen to approximately three quarters of the pressure arranged by the spring and prevailing at maximum volume of the reject flow. This operation is arranged structurally such that onto the shaft of the cone is fixedly supported a transverse plate abutting the inner wall of the body, which as pressed by the compression spring is supported by the end of an element connected to the end of the body, wherein the cone is in its lowest position.

Water or wastewater filtration processes and systems have a plurality of membrane modules, each having filter media therein, the plurality of membrane modules arranged in parallel fluid flow, a main bottom feed conduit, a main top feed conduit, and separate feed conduits fluidly connecting the main bottom feed conduits and the main top feed conduits to respective membrane modules. A main filtrate conduit, and separate filtrate conduits fluidly connect respective membrane modules to the main filtrate conduit. A backwash conduit fluidly connects the main filtrate conduit to respective membrane modules through the main top and bottom feed conduits. A pump having a pump feed conduit and a pump discharge conduit, the pump discharge conduit fluidly connected to the main top and bottom feed conduits, and a plurality of automatically controllable valves positioned in the main top and bottom feed conduits, the main filtrate conduit, the pump discharge conduit, and the backwash conduit, with a controller configured to actuate the plurality of automatically controllable valves to control feed and backwash flows through the membrane modules using pressure developed only by the pump. The pump is preferably operated by a variable-speed prime mover.

The present invention includes: a first sealing portion which has a first entry/exit selectively opened or closed by a first opening/closing valve and a second entry/exit selectively opened or closed by a second opening/closing valve and is configured to seal one end of a housing; a second sealing portion which has a third entry/exit selectively opened or closed by a third opening/closing valve and a fourth entry/exit selectively opened or closed by a fourth opening/closing valve, and is configured to seal the other end of the housing; and a controller which is configured to control the supply of raw water through any one of the first entry/exit and the second entry/exit or control the supply of raw water through any one of the third entry/exit and the fourth entry/exit.