A fluid treatment apparatus includes: a first tank portion arranged to receive a first fluid from a first fluid source; a second tank portion adapted to contain a second fluid and receive water molecules of the first fluid from the first tank portion, wherein the concentration of the second fluid is higher than that of the first fluid; a third tank portion arranged to collect the water molecules of the first fluid from the second tank portion; a first membrane positioned between the first and second tank portions and arranged to filter the water molecules of the first fluid from the first tank portion; and a second membrane positioned between the second and third tank portions and arranged to obtain the water molecules of the first fluid from the second tank portion, wherein the second membrane has a greater permeability than that of the first membrane.

The present invention relates to a method for recovering N, K, and P from liquid waste stream, preferably from a stream of urine, or from a stream comprising excreta (e.g. faeces, manure, digestate, fertilizer), or from (concentrated) wastewater, for example, municipal (e.g. sewage, septic) and/or industrial wastewater (e.g. food and feed industry, agriculture, mining, etc.); more preferably from urine, such as human or animal urine; most preferably from human urine.

An air channel membrane distiller (1) comprises a hot surface (12), a cooling section (20) and a hydrophobic membrane (30). The hot surface and the hydrophobic membrane define a sealed evaporation channel (40). A surface (22) of the cooling section and the hydrophobic membrane define a sealed condensation channel (50). A water supply tubing (42) is connected to the evaporation channel. A water discharge tubing (46) is connected to the evaporation channel. A purified-water discharge tubing (56) is connected to the condensation channel. The surface of the cooling section is given a temperature lower than a temperature of water in the evaporation channel. A gas supply arrangement (60) for inert gas comprises a heater (62). A gas pipe system (64) is arranged to a gas inlet (55) of the condensation channel for enabling flushing of at least the condensation channel with the inert gas.

This document describes systems and methods for treating and recovering water from feed solutions using a multilayer module with an expansion chamber. The multilayer module comprises a feed spacer layer, a permeate spacer layer and a membrane layer, wherein water vapor evaporated from the feed solution in the feed spacer passes through the membrane layer into the permeate spacer layer. The expansion chamber receives the water vapor from the permeate spacer layer and the feed solution from the feed spacer layer.

A membrane for water collection may include a sheet having a top surface and a bottom surface, and a plurality of conical structures disposed on the top surface of the sheet, the conical structures comprising a hydrogel material. Each conical structure of the plurality of conical structures may have a height of 1 mm to 50 mm, wherein height is measured from the top surface of the sheet to an apex of a conical structure. Each conical structure of the plurality of conical structures may have an apex angle of 10 to 60 degrees.

Exemplary embodiments in desalination by direct contact membrane distillation present a cylindrical cross-flow module containing high-flux composite hydrophobic hollow fiber membranes. The present embodiments are directed to a model that has been developed to describe the observed water production rates of such devices in multiple brine feed introduction configurations. The model describes the observed water vapor production rates for different feed brine temperatures at various feed brine flow rates. The model flux predictions have been explored over a range of hollow fiber lengths to compare the present results with those obtained earlier from rectangular modules which had significantly shorter hollow fibers.

A membrane distillation (MD) module includes a first MD sub-module including a first thermocouple; a second MD sub-module including a second thermocouple; and a distillation membrane sandwiched between the first MD sub-module and the second MD sub-module. A hot chamber of the first MD sub-module is closed by the distillation membrane, and a cold chamber of the second MD sub-module is closed by the distillation membrane.

The present invention generally relates to systems and methods for the separation and removal of carbon dioxide from a liquid, for example, seawater. The systems include an extraction system that collects carbon dioxide from the seawater through a medium, and removes carbon dioxide from the medium; the extraction systems comprising a reactor and a membrane. Alternatively, the extraction system includes a reactor, a membrane and a catalyst.

Disclosed herein are systems and methods for purifying aqueous solutions. For example, disclosed herein are flexible membrane distillation systems comprising one or more stages stacked on top of each other, wherein each stage comprises: a feedwater layer; a membrane distillation layer; a distillate layer; and a thermally conductive layer. The systems further comprise substantially impermeable top surface, bottom surface, and perimeter. Each feedwater layer is independently receives a portion of a contaminated aqueous solution (a feed solution). Each feedwater layer further receives heat from a heat source to distill at least a portion of the feed solution through the membrane distillation layer, thereby producing a distillate in the distillate layer. Distilling said portion of the feed solution through the membrane distillation layer purifies said portion of the feed solution to produce a purified aqueous solution, which is condensed in the distillate layer to form a condensate.

There is provided a multi-layered membrane comprising a top layer, a bottom layer, and a spacer layer; wherein said spacer layer is interposed between said top layer and said bottom layer; wherein said top layer, said bottom layer and said spacer layer are each independently composed of one or more selective layers, each selective layer comprising a 2D material; wherein said spacer layer comprises at least one channel for receiving a fluid; wherein said bottom layer comprises a hole with an area in the range of 1 μm.sup.2 to 1 mm.sup.2; and wherein said hole is capable of being in fluid communication with said at least one channels of said spacer layer.

There is also provided a method to synthesize the top layer of a multi-layered membrane as disclosed herein, methods for separating a plurality of ions or molecules in a fluid stream, a device comprising a multi-layered membrane as disclosed herein, and use of the method or the device as disclosed herein in osmotic power generation.