A fluid treatment system, for example a membrane filtration system, utilizing means to mechanically vary fluid recovery and energy recovery to optimize fluid production for a given energy input, based on the total dissolved solids concentration in the fluid feed stream.

A method and a system of generating electrical power or hydrogen from thermal energy is disclosed. The method includes separating, by a selectively permeable membrane, a first saline solution from a second saline solution, receiving, by the first saline solution and/or the second saline solution, thermal energy from a heat source, and mixing the first saline solution and the second saline solution in a controlled manner, capturing at least some salinity-gradient energy as electrical power as the salinity difference between the first saline solution and the second saline solution decreases. The method further includes transferring, by a heat pump, thermal energy from the first saline solution to the second saline solution, causing the salinity difference between the first saline solution and the second saline solution to increase. The method and system may include a regeneration process, such as membrane distillation, forward osmosis, electrodialysis, salt evaporation and/or salt decomposition.

An osmotic power generator comprising an active membrane supported in a housing, at least a first chamber portion disposed on a first side of the active membrane for receiving a first electrolyte liquid and a second chamber portion disposed on a second side of the active membrane for receiving a second electrolyte liquid, a generator circuit comprising at least a first electrode electrically coupled to said first chamber, and at least a second electrode electrically coupled to said second chamber, the first and second electrodes configured to be connected together through a generator load receiving electrical power generated by a difference in potential and an ionic current between the first and second electrodes. The active membrane includes at least one pore allowing ions to pass between the first and second sides of the membrane under osmosis due to an osmotic gradient between the first and second electrolyte liquids to generate said difference in potential and ionic current between the first and second electrodes.

A method for treating water including intaking a first amount of water into a plurality of treatment blocks, treating the first amount of water, outputting aqueous treated water streams from each of the plurality of treatment blocks, separating the aqueous treated water streams from each of the plurality of treatment blocks into aqueous permeate streams and concentrate reject streams, monitoring each of the aqueous permeate streams, controlling the operation of at least one of the plurality of treatment blocks based on predefined water-characteristic tolerances that fall within a predetermined concentration range based on the different qualities of the aqueous permeate streams, combining the aqueous permeate streams of at least two of the plurality of treatment blocks based on the identified characteristics and the predefined water-characteristic tolerances, and outputting the product water stream and the at least one concentrate reject stream.

A method for treating water including intaking a first amount of water from a first source into a plurality of treatment blocks, treating the first amount of water, outputting aqueous treated water streams from each of the plurality of treatment blocks, separating the aqueous treated water streams from each of the plurality of treatment blocks into aqueous permeate streams and concentrate reject streams, monitoring each of the aqueous permeate streams, controlling the operation of at least one of the plurality of treatment blocks based on predefined water-characteristic tolerances that fall within a predetermined concentration range based on the different qualities of the aqueous permeate streams, outputting a product water stream into an injection water reservoir or blend point, the product water stream including the aqueous permeate stream, intaking a second amount of water from a second source, treating the second amount of water, and discharging the dischargeable water stream.

A reverse osmosis system and method of operating the same includes a membrane housing comprising a reverse osmosis membrane therein. The membrane housing has a feed fluid input, a brine outlet and a permeate outlet; The system further includes a charge pump, a plurality of valves and a tank having a volume comprising a movable partition dividing the volume into a first volume and a second volume. The plurality of valves selectively couples the charge pump to the first volume or the second volume and the brine outlet to the second volume or the first volume respectively.

An example water purification system for purifying high concentration feed solutions includes a high rejection forward osmosis module, one or more low rejection modules, and a high rejection reverse osmosis module. The low rejection modules may have different rejection levels. The system may be pressurized by one or more pumps. One or more of the low rejection modules may include one or more nanofiltration (NF) membranes. The draw solution may comprise a monovalent salt, a multivalent salt, or a combination of both.

A high recovery variable volume reverse osmosis system where the volume of concentrate cycled through the RO system is reduced in response to recovery levels increasing. By reducing the volume of concentrate cycled through the RO system, this reduces the cycle time of highly saturated concentrate passing through the RO system. Reducing the cycle time of concentrate passing through the RO system tends to minimize or reduce membrane scaling.

Reverse osmosis (1) system having a first membrane unit (2) and at least a second membrane unit (3), the membrane units (2, 3) forming a chain of membrane units, the first membrane unit (2) having a first membrane (4) separating a first feed chamber (5) and a first permeate chamber (6), a first inlet (7) connected to the first feed chamber (5), a first permeate outlet (9) connected to the first permeate chamber (6), and a first concentrate outlet (8) connected to the first feed chamber (5), the second membrane unit (3) having a second membrane (10) separating a second feed chamber (11) and a second permeate chamber (12), a second inlet (13) connected to the second feed chamber (11), a second permeate outlet (15) connected to the second permeate chamber (12), and a second concentrate outlet (14) connected to the second feed chamber (11), wherein the concentrate outlet (8) of a membrane unit (2) in the chain of membrane units is connected to an inlet (13) of a following membrane unit (3) and a concentrate outlet (14) of at least one membrane unit (3) downstream the first membrane unit (2) in the chain of membrane units is connected to a hydraulic motor (18). In such a system the energy consumption should be optimized. To this end the hydraulic motor (18) is operatively connected to a first electric machine (21).

An intermediate power store for at least one power generating system, including: an osmosis device, a permeate store, a concentrate store and a control device. The osmosis device is designed to separate, in a charging operation, a liquid mixture with a charging pressure into a permeate and a concentrate, or, in a discharging operation, to mix the permeate with the concentrate while applying an osmotic pressure to the liquid mixture. The permeate store is fluidically connected to the osmosis device and is designed to store the permeate. The concentrate store is fluidically connected to the osmosis device and is designed to store the concentrate. The control device is designed to control the following functions: the charging operation using electrical power from the at least one power generating system, or the discharging operation while providing electrical power.