This specification describes membrane based filtration and softening systems and methods. A system has a microfiltration or ultrafiltration (MF/UF) membrane unit upstream of a nanofiltration or reverse osmosis (NF/RO) membrane unit, optionally with no intermediate tank. In some cases, the system and method may be used with feed water provided at municipal line pressure to the membranes. NF/RO permeate is collected in a tank and then pumped to a header. Treated water may be drawn from the header for use or recycled to the system, for example to backwash or flush one or both of the membrane units. In a combined process, NF/RO permeate flushes the feed side of the NF/RO unit and then backwashes the MF/UF unit. In another process, the MF/UF unit and NF/RO unit are filled with NF/RO permeate before being placed in a standby mode.

A top fill water reservoir system that allows the reservoirs to be filled without waiting for a reverse osmosis (RO) filter to produce enough water to fill the system and avoids the need for a service worker to remove the system from the cabinet, or wait for RO filtration, to fill the reservoirs. The top fill water reservoir system comprises a drinking reservoir adapted to store and dispense drinking water. A supply reservoir in fluid communication with the drinking reservoir and adapted to feed water into the drinking reservoir and receive water from a reverse osmosis (RO) filter. An overflow tube adapted to connect an upper portion of the drinking reservoir to the supply reservoir and feed overflow water from the drinking reservoir to the supply reservoir.

A water purification system (100) is provided and includes: a composite filter cartridge assembly (1), a booster pump (4), a waste-water solenoid valve (7) and a water storage device. The composite filter cartridge assembly (1) includes a filter casing (11) and a composite filter cartridge (12). A pretreated-water outlet (114) of the filter casing (11) is connected with a water-output end of a pretreating filter cartridge (121) of the composite filter cartridge (12) and with the booster pump (4). A pretreated-water inlet (115) of the filter casing (11) is connected with a water-input end of a fine filter cartridge (122) of the composite filter cartridge (12) and with the booster pump (4). A purified-water port (116) of the filter casing (11) is connected with a water-output end of the fine filter cartridge (122), a water-input end of a mouthfeel-improving filter cartridge (123) of the composite filter cartridge (12) and the water storage device.

A water filtration system is provided and includes a raw-water inlet, a pure-water outlet, a purified-water outlet, a waste-water outlet and an integrated filter cartridge. The integrated filter cartridge has a first port, a second port, a third port, a fourth port, a fifth port and a sixth port. The first port is connected to the raw-water inlet, and the second port is connected to the purified-water outlet, a connection conduit is connected to the third port, and a free end of the connection conduit is connected between the second port and the purified-water outlet, the fourth port is connected to the pure-water outlet, the fifth port is connected to the waste-water outlet, at least one of a conduit in connection with the pure-water outlet and the sixth port is provided with a water storage device.

A fixed or mobile water treatment system comprises a primary screening tank that filters wastewater to remove inorganic and organic pollutants from the wastewater, and includes an electro-coagulation unit that provides an electrical charge to wastewater exiting the primary screening tank, ultraviolet light and oxidation processes in one or more settling tanks that remove pollutants from the wastewater, and one or more filters that remove pollutants from the wastewater.

A filtering device is for obtaining a chemical liquid by purifying a liquid to be purified, and the filtering device has an inlet portion, an outlet portion, a filter A, at least one filter B different from the filter A, and a flow path which includes the filter A and the filter B arranged in series and extends from the inlet portion to the outlet portion, in which the filter A is a porous membrane containing a polyimide-based resin.

Disclosed are a hybrid system and method of waste heat utilization-based photovoltaic power generation and seawater desalination, wherein a photovoltaic power generation unit includes a linear Fresnel lens, a beam-splitting cooling tube, a solar cell, and a heat collecting tube; a seawater supply unit includes a seawater storage tank and a pre-treatment storage tank; a heat storage and temperature control unit includes a phase-change heat reservoir and heat exchangers; an electrodialysis unit includes poles, an ion-selective membrane, a desalination chamber, a concentration chamber, pole chambers, a concentrated liquid storage tank and a desalinated liquid storage tank; and an electricity storage and control unit includes a battery pack and a circuit controller. Incident sunlight achieves photovoltaic power generation by a light condensation followed by beam splitting mode; nanoparticle doped seawater absorbs long-wavelength light and transmits short-wavelength light.

The invention relates to liquid purification and/or desalination systems, predominantly water from different sources, and is used in household and/or drinking water supply, in suburb and country houses. Liquid purification system, comprising of raw liquid line with the inlet valve, reverse osmosis membrane connected to drainage line and purified liquid line and purified liquid consumption line and purified liquid vessel, secondary purified liquid line, connected to purified liquid vessel and to raw liquid line and to console panel, characterized in that debris layer on the reverse osmosis membrane is near totally dissolved by intensive repeated flushing of the reverse osmosis membrane with purified liquid.

Described embodiments include a graphene membrane film for solvent purification and related method, and a solvent purification system using same. The graphene membrane film for solvent purification is formed having a plurality of stacked graphene plate-shaped flakes, and at least one pair of the plurality of stacked graphene plate-shaped flakes comprises a physical bond or a chemical bond connecting layers. The graphene membrane film for solvent purification is produced by preparing a graphene oxide dispersion liquid by dispersing graphene oxide in distilled water; confining the graphene oxide dispersion liquid between a pair of substrates; and applying heat and pressure to the graphene oxide dispersion liquid between the substrates to perform a hydrothermal reaction to concurrently thermally reduce the graphene oxide and bind graphenes. Due to lipophilic surface property and fine pores, size exclusion separation and hydrophilic-lipophilic component separation through polarity may be realized, and thus is usable in fine chemistry fields.

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.