Algae harvesting and cultivating systems and methods for producing high concentrations of algae product with minimal energy. In an embodiment, a dead-end filtration system and method includes at least one tank and a plurality hollow fiber membranes positioned in the at least one tank. An algae medium is pulled through the hollow fiber membranes such that a retentate and a permeate are produced.

A system for producing steam includes a steam generator with steam output; a membrane filtration system in fluid communication with the steam output and including a membrane filter with a permeate side and an opposing retentate side. The membrane filter includes a separation membrane constructed to reject organic molecules. The system may be used for removing organic compounds, such as anti-corrosion agents or contaminants, from steam.

A peritoneal dialysis apparatus includes a filter and a dialysis fluid circuit in fluid communication with the filter. The peritoneal dialysis apparatus also includes a pump for pumping fresh dialysis fluid to a peritoneum of a patient via the dialysis fluid circuit and pumping used dialysis fluid from the peritoneum of the patient through the dialysis fluid circuit and the filter. The peritoneal dialysis apparatus further includes a selective air access in fluid communication with the dialysis fluid circuit and a control unit configured to control the pump during a peritoneal dialysis treatment and a filter cleaning sequence. The control unit forms a fluid mixture during a filter cleaning sequence by opening the selective air access to mix air with a physiologically safe fluid. The fluid mixture is transferred across insides and/or outsides of the filter at least one time.

A fluid filtration system includes a fluid storage vessel such as a bioreactor, a filter housing including a filter element disposed therein, a pump coupled between the fluid storage vessel and the filter housing, and a flow diverter disposed between the pump and the filter housing. The pump is configured to move fluid from the fluid storage vessel through the filter element, and the flow diverter is configured for selectively directing fluid received from the pump to the first or second end of the filter housing. In a first mode of operation, the flow diverter directs flow through the filter housing in a first direction, while in a second mode of operation, the flow diverter directs flow through the filter housing in a second direction opposite the first direction.

A renal therapy apparatus includes a blood filter, a blood pump, a treatment fluid pump, and a control unit configured to control at least one of the blood pump or the treatment fluid pump during a filter cleaning sequence. The blood filter includes a plurality of hollow fiber membranes. During the filter cleaning sequence, a fluid mixture is formed by mixing air with a blood-compatible and physiologically safe fluid. Also during the filter cleaning sequence, the fluid mixture is transferred across insides and/or outsides of the plurality of hollow fiber membranes at least one time. The use of the fluid mixture enables the filter cleaning sequence to be performed during the blood treatment.

A desalination brine dispersal apparatus and method employ airlift to remove, oxygenate and disperse brine from a desalination apparatus. The apparatus includes a brine removal conduit having a brine inlet that receives brine from the desalination apparatus, a plurality of brine outlets submerged in seawater and one or more air introduction points located at depths below the brine outlets. The supplied air oxygenates and moves brine through the brine removal conduit and outlets via airlift and disperses the brine into seawater away from the brine removal conduit. The apparatus avoids the formation of concentrated, high shear brine plumes and can disperse brine into seawater over a wide area well away from the brine removal conduit.

A desalination brine dispersal apparatus and method employ airlift to remove, oxygenate and disperse brine from a desalination apparatus. The apparatus includes a brine removal conduit having a brine inlet that receives brine from the desalination apparatus, a plurality of brine outlets submerged in seawater and one or more air introduction points located at depths below the brine outlets. The supplied air oxygenates and moves brine through the brine removal conduit and outlets via airlift and disperses the brine into seawater away from the brine removal conduit. The apparatus avoids the formation of concentrated, high shear brine plumes and can disperse brine into seawater over a wide area well away from the brine removal conduit.

A method and apparatus for improved separation and containment of radioactive particulates from liquids by filtration. The improvements are achieved by utilizing more than one stage of filtration to remove radioactive particulates from a fluid. The first stage of filtration is designed for high liquid flowrate, low differential pressure across the filter medium, and reversibility of flow through the medium to facilitate backwashing. The second or more stages of filtration receive the backwash flow and captured particulates from the first stage at a lower flowrate, but at high pressure using a high-pressure pump configured between the stages.

A filtration device includes a continuous first unit including a first membrane that separates a liquid into first permeated and non-permeated liquids, a first adjuster that adjusts a flow rate of the first permeated liquid to be substantially constant, and a first liquid scale that detects a liquid amount, a second unit including a second membrane that separates another liquid into second permeated and non-permeated liquids, a second adjuster that adjusts a flow rate of the second permeated liquid to be substantially constant, and a second liquid scale that detects another liquid amount, a first controller that controls the liquid amount in the first storage tank based on measurement values from continuous two first units or from the continuous first and second units, and a second controller that controls the another liquid amount based on a measurement value from the second unit.

Methods and apparatuses for adding gas bubbles to a tank containing liquid at locations that allow the bubbles to rise to the top of the tank are disclosed. One embodiment comprises a membrane filtration system connected to a gas source and a drain. The membrane filtration system draws gas into the system from the gas in response to a reduced pressure profile created by opening a drain. The gas may be air supplied at atmospheric pressure.