The invention relates to 100% renewably-powered desalination/water purification stations for universal applications, the station is disruptive, scalable, amphibious and deportable to seawater, brackish or spill oil sites for simple wave-powered and autonomous operations, the station has a mooring assembly with pumping-purification-delivery subsystems powered by wave and solar energies, the pumping subsystems has the simplest, most efficient wave push/pull pump mechanisms powered by amplified wave centrifugal forces , the mechanical purifications has turbine filters, reverse-osmosis filters, forward-osmosis filters and relief valves to backwash buildups without releasing brine, release water through collecting spill oil, the solar thermal purifications are provided with distilling processes under vaccine conditions, the delivery subsystems with wave turbines and solar panels for generating electricity, propellering and transferring the stations for delivering fresh waters to destinations under GPS guide with the lowest LCOW.

A filtration device includes a first channel member, a second channel member, and a filter. The first channel member has a recess recessed inward from an outer wall surface. A groove is formed is the recess and has an opening in a recessed surface of the recess. First and second channels, each defined by a through-hole, are formed in the first channel member and are connected to the groove. A first connection part connects the groove with the first channel. The second channel member has a projection that detachably mates with the recess. The second channel member includes a discharge channel that has an opening in a projecting surface of the projection, the opening being located over the groove. The filter is disposed along the groove, and positioned at the opening of the discharge channel. When the first and second channel members are placed in a operative relationship, a third channel is formed by the projecting surface of the projection and the opening of the groove. The third channel is connected to the first channel via the first connection part. The third channel at which the filter is positioned has a smaller cross-sectional area than the first channel.

Disclosed are methods of treating wastewater using a membrane bioreactor and achieving a target phosphorus concentration for the membrane permeate stream. These methods include the steps of dosing a wastewater stream with a rare earth clarifying agent and passing the dosed wastewater stream through the membrane to obtain a membrane permeate stream with a permeate concentration that is less than the phosphorus concentration of the influent stream. This permeate concentration also can be equal to or less than a target phosphorus concentration. In the methods as disclosed herein, the rare earth clarifying agent can be chloride salts of one or more rare earth elements and in certain embodiments, the rare earth clarifying agent can be CeCl.sub.3 and LaCl.sub.3.

A device for tangential flow filtration includes a filter unit having first and second fluid openings, a filter element and a permeate opening, a first flow connection to connect the first fluid opening to a reservoir, a second flow connection to connect the second fluid opening to the reservoir, a first centrifugal pump in the first flow connection to convey the fluid from the reservoir to the filter unit, a first controller to actuate the first centrifugal pump, the filter unit designed such that the fluid for tangential flow filtration is capable of flowing substantially parallel to the filter element, a second centrifugal pump in the second flow connection, with which a counter-pressure is capable of being generated at the second fluid opening, and a second controller to actuate the second centrifugal pump.

A method of concentrating lithium containing solutions includes inputting a feed brine solution to an initial separation stage, the feed brine solution including lithium sulfate and one or more of sodium sulfate, potassium sulfate, calcium sulfate, and sodium chloride dissolved in water. In the initial separation stage, the feed brine solution is introduced to a pre-treatment membrane at a pressure that is less than the osmotic pressure of the feed brine solution. An initial permeate that passes through the pre-treatment membrane becomes the feed to a final separation stage, and an initial retentate that does not pass through the pre-treatment membrane includes a precipitate of at least one of the salts other than lithium sulfate. In the final separation stage, the initial permeate is introduced to a nanofiltration membrane at a pressure that is less than the osmotic pressure of the initial permeate. A final retentate that does not pass through the nanofiltration membrane is combined with the initial retentate to obtain a product solution having a higher concentration of dissolved lithium sulfate than the feed brine solution.

A system for treating a tetraalkylammonium hydroxide-containing liquid having a high-pressure type reverse osmosis membrane device concentrating a liquid to be treated containing tetraalkylammonium hydroxide at a concentration side, and a line for supplying the concentrated liquid to be treated by the reverse osmosis membrane device to an evaporator further concentrating the concentrated liquid to be treated.

A system for treating a tetraalkylammonium hydroxide-containing liquid having a high-pressure type reverse osmosis membrane device concentrating a liquid to be treated containing tetraalkylammonium hydroxide at a concentration side, and a line for supplying the concentrated liquid to be treated by the reverse osmosis membrane device to an evaporator further concentrating the concentrated liquid to be treated.

Biocide can be controllably added to a feed stream for a membrane. In some examples, the feed stream is separated into a primary feed stream and a secondary feed stream, for example, with the secondary feed stream having a lower flow rate than the primary feed stream. The secondary feed stream may be used to monitor and control the addition of the biocide, which is then diluted when the secondary feed stream is combined with the primary feed stream to form a combined stream for delivery to the membrane.

Biocide can be controllably added to a feed stream for a membrane. In some examples, the feed stream is separated into a primary feed stream and a secondary feed stream, for example, with the secondary feed stream having a lower flow rate than the primary feed stream. The secondary feed stream may be used to monitor and control the addition of the biocide, which is then diluted when the secondary feed stream is combined with the primary feed stream to form a combined stream for delivery to the membrane.

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.