An ocean alkalinity enhancement (OAE) system that reduces atmospheric CO.sub.2 and mitigates ocean acidification by electrochemically processing feedstock solution (e.g., seawater or brine) to generate an alkalinity product that is then supplied to the ocean. The OAE system includes a base-generating device and a control circuit disposed within a modular system housing deployed near a salt feedstock. The base-generating device (e.g., a bipolar electrodialysis (BPED) system) generates a base substance that is then used to generate the ocean alkalinity product. The control circuit controls the base-generating device such that the alkalinity product is supplied to the ocean only when (1) sufficient low/zero-carbon electricity is available, (2) it is safe to operate the base-generating device, and (3) supplying the alkalinity product will not endanger sea life. Modified BPED systems include features that facilitate autonomous system operations including enhanced maintenance cycle operations and a reduced reliance on external fresh water sources.

The degassing device includes a degassing flow path, a vacuum chamber, a vacuum pump, an inlet flow path, an outlet flow path, a drain flow path, a downstream side switching unit, and a controller. The degassing flow path is made of a gas-permeable, liquid-impermeable tube, and is accommodated in the vacuum chamber. The inlet flow path is for introducing a mobile phase to the degassing flow path, and the outlet flow path is for causing a mobile phase which has passed through the degassing flow path to flow out. The drain flow path is provided separately from the outlet flow path and is configured to drain the mobile phase in the degassing flow path from the degassing flow path. The downstream side switching unit is configured to switch the downstream end of the degassing flow path so as to be connected to either the outlet flow path or the drain flow path. The controller controls the operation of the downstream side switching unit, and is configured to connect the downstream end of the degassing flow path to the drain flow path at a predetermined timing when feeding of the mobile phase by the liquid feeding pump is stopped to drain the mobile phase in the degassing flow path through the drain flow path.

There is provided a thin film composite (TFC) hollow fibre membrane comprising a porous hollow fibre support layer formed of a polymer and a selective layer, formed of a cross-linked polyamide, on an inner circumferential surface of the hollow fibre support layer, wherein the TFC hollow fibre membrane has a power density of 25-50 W/m.sup.2 at a pressure of 30 bar. There is also provided a method of forming the TFC hollow fibre membrane.

A method of recovering draw agent utilised in a forward osmosis membrane cell, the method comprising the steps of passing diluted draw agent to a vapour-liquid separator; using the vapour-liquid separator to separate draw agent vapour and solvent; and condensing draw agent vapour.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

A process for solution mining of minerals is disclosed. The process comprises injecting an unsaturated stream (150) at an injection pressure into a mineral formation (130) to dissolve the mineral and extracting a high concentration stream (110) containing said dissolved mineral. The process comprising converting latent osmotic energy present in said high concentration stream into an increase in the total pressure of said stream by passage through an osmotic power unit (200) and generating electricity and reducing to the injection pressure the total pressure of a reduced concentration output stream (150) by passage through a power generating device (250) and using the reduced concentration output stream (150) at the injection pressure as the unsaturated stream (150). A process for storing a fuel in an underground formation is also disclosed.

The present invention relates to a device and to a method for producing dialysate, wherein the device comprises a first part and a second part designed as a circuit, wherein the first part comprises a water connection or a water container and the primary side of a filter, wherein the filter is designed to produce purified water from the water by forward osmosis, and wherein the second part comprises the secondary side of the filter, a reservoir, a filtrate line which leads from the secondary side of the filter to the reservoir, and a return line leading from the reservoir to the secondary side of the filter, wherein an electrodialysis unit comprising a diluate chamber and a concentrate chamber is further provided, wherein the concentrate chamber is fluidically connected to the secondary side of the filter.

Systems and methods of gas-liquid contactors for direct ocean capture and/or direct air capture are described.

The oxygenator of organic fluids comprises: a container body having a longitudinal axis; a first inlet opening for the oxygen and a second outlet opening for an exhaust gas obtained in the container body; a third inlet opening for an organic fluid to be oxygenated and a fourth outlet opening for oxygenated organic fluid obtained in the container body; an oxygenation chamber of the fluid to be oxygenated that is defined inside the container body; a distribution pre-chamber of the fluid to be oxygenated fitted between the third inlet opening and the oxygenation chamber; a mass of capillary fibers that are impermeable to liquids and porous to gasses, designed to be lapped by the organic fluid and arranged inside the oxygenation chamber according with a common parallel direction; dynamic distribution means supported in the distribution pre-chamber by support means.

A draw solute for the forward osmosis membrane process comprises a random copolymer obtainable by random addition of a monomer containing ethylene oxide and butylene oxide to a compound having one or more hydroxyl groups.