A multi-effect membrane distillation system includes first and second membrane distillation effects. Each effect (stage) includes a feed channel, a gap, and a vapor-permeable membrane separating the feed channel from the gap. A liquid feed is fed into the feed channel of the first effect via a feed inlet, and the liquid feed is extracted from the first-stage feed channel via a first feed-transfer conduit that delivers the liquid feed to the second-stage feed channel. The feed is extracted from the second-stage feed channel via a second feed-transfer conduit. At least one permeate-extraction conduit is coupled with the first-stage and second-stage gaps and is configured to extract permeate (e.g., pure water) therefrom.

The solar desalination system is a hybrid system combining a Fresnel solar concentrator with a desalination chamber, and which uses membrane distillation for desalination of seawater. The desalination chamber includes a lower wall having a central absorber base, at least one sidewall, and an upper wall. A pair of hydrophobic membranes are mounted within the desalination chamber such that a central chamber is defined therebetween above the absorber base. The desalination chamber is suspended above a linear Fresnel reflector array so that the absorber base is positioned at a focal line thereof. Seawater is fed into the central chamber, where it is heated to produce water vapor, which passes through the pair of hydrophobic membranes into a pair of condensate retrieval chambers. The water vapor cools in the pair of condensate retrieval chambers, and may then be removed in the form of pure water.

The hybrid desalination system (10) includes a reverse osmosis filtration system (14), a forward osmosis filtration system (18), and a multi-effect distillation system (16). A condenser (12) receives seawater (S) and produces cooled seawater (CS). The cooled seawater (CS) is filtered by the reverse osmosis filtration system (14), which outputs a first brine reject stream (BR1) and a permeate stream (P). The multi-effect distillation system (16) outputs a second brine reject stream (BR2). A feed side (20) of the forward osmosis filtration system (18) receives the first brine reject stream (BR1), and the second brine reject stream (BR2) is received by the draw side (22), which outputs diluted brine (DB). The multi-effect distillation system (16) is in fluid communication with the forward osmosis filtration system (18) and recycles the diluted brine (DB). The multi-effect distillation system (16) outputs a return condensate (RC) and a pure water distillate (D).

A system and method for effectively desalinating a source of water is provided. The source of water is desalinated by a desalination train comprising at least a heat exchanger, a plurality of flashing stages comprising hydrophobic membranes under reduced pressure, and at least a compression device. The source of water is passed through the heat exchanger prior to passing through the flashing stages to bring it to a vaporizing temperature by maintaining the flashing stages at reduced pressure so that at least a portion of water flashes into vapor. The vapor from the flashing stages is withdrawn, and at least a portion of the withdrawn vapor is compressed by the compression device. The compressed vapor is then condensed in the heat exchanger to produce a distillate stream, and heat the source of water before it enters the flashing stages.

A device for purifying liquids by distillation includes a first and a second evaporation section, and a first and a second condensation section, where each evaporation section includes a liquid inlet and a vapor outlet and each condensation section includes a vapor inlet and a liquid outlet, the first evaporation section and the second condensation section being in vapor connection through the first evaporation section outlet and the second condensation section inlet, wherein the first evaporation section is in thermal contact with the first condensation section, and the second evaporation section is in thermal contact with the second condensation section, wherein the sections in thermal contact are separated by a non-permeable polymer membrane. The device is compact and efficient in the production of a distillate product.

This disclosure relates to a multistage distillation system for concentrating a feed liquid, the system including at least one module being assembled by a stack of frame elements, wherein each module includes at least one stage, such that the system includes in total a plurality of stages configured to be flowed through in series by a main feed liquid. Each stage of the plurality of stages is configured to generate steam and feed the steam to a subsequent stage. The first stage of the plurality of stages is configured to heat the main feed liquid and/or to be fed with heated main feed liquid. The system further includes an intermediate cooling device configured to cool the heated main feed liquid before flowing to at least one of the second to last stages of the plurality of serial stages.

A resource recovery method includes: feeding raw water to a first-stage raw water tank; supplying high-temperature vapor to a first-stage heat exchanger; performing heat exchange between the supplied high-temperature vapor and the raw water in the first-stage raw water tank, changing a portion of the water into vapor and supplying the changed vapor to a subsequent-stage heat exchanger; repeatedly performing the performing step for each of the raw water tanks sequentially in the order from a second state to a n-th stage; being feed to a crystallizer from the n-th stage raw water tank; detecting a turbidity of the raw water fed to the crystallizer from the n-th-stage raw water tank; and extracting crystals of valuable resources contained in the raw water fed to the crystallizer from the n-th-stage raw water tank when the turbidity of the raw water becomes a predetermined value.

Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and/or impedance sensors) mounted on the porous surface. In another example, a membrane distillation (MD) process includes the membrane. Processing circuitry can be configured to monitor outputs of the plurality of sensors. The monitored outputs can be used to determine membrane degradation, membrane fouling, or to provide an indication of membrane replacement or cleaning. The sensors can also provide temperatures or temperature differentials across the porous surface, which can be used to improve modeling or control the MD process.

A multi-stage submerged membrane distillation water treatment apparatus including: a plurality of raw water tanks arranged in multiple stages ranging from a first stage to an n-th stage and storing raw water, the raw water flowing sequentially from the first stage to the n-th stage; membrane distillation (MD) modules submerged in the respective raw water tanks and discharging a portion of the raw water as vapor; heat exchangers submerged in the respective raw water tanks and maintaining the raw water at a predetermined temperature by performing heat exchange between the raw water and vapor supplied from the respective previous-stage MD modules; a vapor generator generating and supplying high-temperature vapor to the first-stage heat exchanger; a condenser condensing vapor supplied by the n-th-stage MD module; and a raw water feeder feeding low-temperature raw water to the first-stage raw water tank via the condenser.

A photothermal distillation membrane including a polydopamine (PDA) coated, polyvinylidene fluoride (PVDF) membrane is disclosed, as well as a process for synthesizing same. A photothermal aerogel membrane including a polydopamine (PDA)-containing bacterial nanocellulose (BNC) is also disclosed, as well as a process for synthesizing same.