A water filtering device can comprise: a filter, an optional prefilter, and two stages pumping system with recirculation circuit is disclosed. The pumping system is formed with two pistons, merged together where the recirculation piston is further equipped with at least one non-return valve. During the intake phase, the chambers are filed through the pair of non-return valves, while the concentrate and the feedwater are mixed through the non-return valve. During the compression, the valve is closed, and the pressure generated by the piston within the chamber is transmitted to the chamber and subsequently towards the filtering means. Permeate is extracted out while the concentrate is sent to the chamber by the recirculation. The system can achieve pressure sufficient for ultrafiltration, nanofiltration or reverse osmosis of any water type available.

A submersible water desalination apparatus includes a plurality of water separation membrane elements, a product water collector that receives product water from the membrane elements, and a variable output motorized submersible pump having a suction side that receives product water from the product water collector and a discharge side that pumps product water away from the apparatus through a product water conduit for surface or subsurface use. At least a portion of the product water is used to cool the motor.

A sequentially stacked multi-stage desalination system includes a single pair of electrodes, including an anode and a cathode; at least one ion concentration polarization device; and at least one electrodialysis device coupled with the ion concentration polarization device and configured to receive liquid flow from the ion concentration polarization device. Each ion concentration device and electrodialysis device is positioned between the anode and the cathode.

A system and method of extracting elements from an aqueous stream are described herein. The method includes designing a process to extract at least two elements from the aqueous product stream. The at least two elements have different commercial values. The process is optimized to minimize a cost of extracting the at least two elements and to maximize a value of extracting the at least two elements. The method further includes extracting the at least two elements according to the process.

Wave energy is utilized by and/or seawater is desalinated by a point-absorber-type wave energy converter has: an anchor affixed to an ocean floor, a buoy is tethered to the anchor, and a machine is located on the buoy; the buoy includes a spool system and a recoil system, the spool system has a first spool and a second spool mounted together on a shaft, the recoil system includes a spring, a first line connects the first spool and the anchor, so that as the wave displaces the buoy, the shaft turns and drives the machine, and a second line connects the second spool and the recoil system, so that after the displacement of the buoy, the first line is recoiled onto the first spool.

A potable water producing system for disposition at a salt water body and methods of producing potable water are provided. The system includes a wave energy conversion system (AWECS) and a portable filtration system. The AWECS forms a floating articulated barge having an onboard desalination system including reverse osmosis membranes. The filtration system is a sand filter residing on a damping plate submerged in the salt water body and filters the adjacent salt water for providing filtered salt water to the onboard desalination system. Wave action on the articulated barge provides energy to pump and pressurize the filtered salt water from the sand filter to the reverse osmosis membranes to produce potable water. The wave action on the articulated barge effects shaking of the reverse osmosis membranes, thereby rendering them self-cleaning. The potable water can be used for various applications, e.g., bottling, replenishing aquifers, ground and/or aquifer remediation, irrigation, etc.

A water purification system utilizes an ionomer membrane and mild vacuum to draw water from source water through the membrane. A water source may be salt water or a contaminated water source. The water drawn through the membrane passes across the condenser chamber to a condenser surface where it is condensed into purified water. The condenser surface may be metal or any other suitable surface and may be flat or pleated. In addition, the condenser surface may be maintained at a lower temperature than the water on the water source side of the membrane. The ionomer membrane may be configured in a cartridge, a pleated or flat plate configuration. A latent heat loop may be configured to carry the latent heat of vaporization from the condenser back to the water source side of the ionomer membrane. The source water may be heated by a solar water heater.

Integrated tidal desalination system that harnesses tidal power to produce drinkable water through a mechanically linked or direct drive integrated tidal turbine (ITT) and centrifugal reverse osmosis (CRO) system. The ITT-CRO system eliminates conversion losses in the power take-off unit by eliminating the need for electrical energy conversion. The ITT-CRO system is modelled, and the model used for control, and predictive maintenance.

An exemplary embodiment of the present disclosure provides a method for purifying salt water. The method comprises the steps of removing at least a portion of salt in the salt water to form a potable water and introducing the at least a portion of the salt removed from the salt water to a water feed.

A desalination and cooling system integrating an Ejector Cooling Cycle (ECC) system and a Permeate Gap Membrane Distillation (PGMD) system. The ECC system includes a generator, an evaporator, an ejector, and a condenser. The generator produces a primary flow of refrigerant, the evaporator provides cooling and a secondary flow of the refrigerant, and the ejector combines these flows to generate a super-heated stream of the refrigerant, which the condenser cools. The PGMD system, including a feed chamber, a coolant chamber, a permeate gap chamber, and a membrane with pores, allows water vapors from a hot stream to pass from the feed chamber to the permeate gap chamber. The ECC and PGMD systems are connected at the condenser, where the super-heated stream of the refrigerant heats the cold stream to produce the hot stream, facilitating efficient desalination and cooling.