A membrane distillation system includes a hollow fiber aerator configured to provide gas bubbles to a relatively cool permeate stream so that the relatively cool permeate stream contains gas bubbles when it contacts a porous and hydrophobic membrane in a direct contact membrane distillation process. The system can further include an additional hollow fiber aerator configured to provide gas bubbles to a relatively hot feed stream so that the relatively hot feed stream contains gas bubbles when it contacts a porous and hydrophobic membrane in a direct contact membrane distillation process.

Provided is a membrane distillation system capable of real-time monitoring on membrane scaling, which includes: a raw water storage tank configured to store various kinds of fluid; a membrane distillation water treatment unit configured to receive raw water stored in the raw water storage tank to generate pure water, the membrane distillation water treatment unit having an inlet water chamber into which an inlet water flows from the raw water storage tank, a membrane for separating the inlet water in the inlet water chamber into a steam and a concentrated water, and a treated water chamber for receiving the steam separated by the membrane and concentrating the steam; and a membrane wetting detection unit disposed opposite to the membrane to detect a membrane wetting phenomenon and a membrane wetting location of the membrane by measuring a light passing through the membrane in real time.

Embodiments provide methods and strictures for purification or volume reduction of a brine by an advanced vacuum distillation process (AVMD) to achieve higher flux by passage of vapors through an AVMD distillation unit. In one example, brine is circulated in a tank. The tank may include one or more membrane pouches that are submerged in the circulating brine or placed above the water level of the hot circulating brine. In other embodiments the membrane pouches are outside of the tank that includes the hot circulating brine but still in communication with it. The circulating brine is heated, allowing creation of water vapor. Using a vacuum, the water vapor is drawn through the membrane, where it may be condensed and subjected to further beneficial use. This process can concentrate to levels to generate crystals or solids, which can be separated and utilized.

Membranes including functionalized carbon nanotubes, nanodiamonds and/or graphene oxide immobilized in or on the membranes are disclosed. The membranes including the immobilized nanocarbons increase interactions with water vapor to improve desalination efficiency in membrane distillation. The membranes may be deployed in all modes of membrane distillation such as air gap membrane distillation, direct contact membrane distillation, vacuum membrane distillation and other separations.

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 dosing pump (19) doses antiscalant into a membrane-based water treatment system (1). The dosing pump (19) includes a displacement body for pumping antiscalant into the membrane-based water treatment system (1) in doses. A motor drives the displacement body. A control module controls the motor. The control module is configured to vary the dosage of antiscalant pumped into the water treatment system (1) based on a temperature corrected system variable (SVTc) being based on a plurality of operating variables of the water treatment system (1).

The present invention is a process, a method, and system for recovery and concentration of dissolved ammonium bicarbonate from a wastewater containing ammonia (NH3) using gas separation, condensation, and crystallization, each at controlled operating temperatures. The present invention includes 1) removal of ammonia from waste (sludges, semi-solids, and solids and liquids) without the use of chemicals at a temperature of at least 80 degrees Celsius, 2) condensing the gaseous containing ammonia, carbon dioxide and water vapor to remove water vapor concentrating the amount of gaseous ammonia and carbon dioxide, 3) concentrating the ammonia and carbon dioxide in the water by established means, such as concentrating the gas using partial condensation followed by passing the concentrated gas through an absorption column at a temperature of between about 20 and 50 degrees Celsius to form dissolved ammonium carbonate and ammonium bicarbonate, or total condensation followed by dewatering using reverse osmosis, and 4) crystallizing concentrated dissolved ammonium carbonate and ammonium bicarbonate at a temperature of less than about 35 degrees Celsius to form solid ammonium bicarbonate and ammonium carbonate.

A membrane distillation apparatus includes a housing and an impeller. The housing includes a hot medium compartment, a cold medium compartment, an air gap compartment, a membrane, and a thermally conductive plate. The hot medium compartment includes a hot medium inlet configured to receive a hot medium stream including water. The cold medium compartment includes a cold medium inlet configured to receive a cold medium stream. The membrane defines pores that are sized to allow water vapor originating from the hot medium stream to pass from the hot medium compartment through the membrane to the air gap compartment. The thermally conductive plate and the cold medium stream are cooperatively configured to condense the water vapor from the hot medium stream. The air gap compartment is substantially filled with air and includes a permeate outlet configured to discharge the condensed water vapor. The impeller is disposed within the air gap compartment.

A deposit monitoring device includes a non-permeated water line discharging non-permeated water where dissolved components and dispersed components are concentrated from water to be treated from a separation membrane device for obtaining permeated water by concentrating the dissolved components and dispersed components from water to be treated by a separation membrane; a first deposit detecting unit using part of the non-permeated water branched off as a detection liquid, and having a first separation membrane for detection in which the detection liquid is separated into permeated water for detection and non-permeated water for detection; a deposition condition altering device altering deposition conditions for deposits in the first separation membranes for detection; and first flow rate measuring devices for separated liquid detection that measure the flow rates of one or both of the permeated water for detection and the non-permeated water for detection separated by the first separation membrane for detection.

Unconventional hydrocarbons production from shale and tight-sand formations unlocks vast new energy sources to the nation. However, public perception about excessive potable water use in hydro-fracturing and possible pollution routes in discharging and reusing produced water (flow-back water) promotes state's stringent regulations and opens the door to develop effective produced water treatment methods. This invention is therefore aimed at properly treating produced water to avert health and environmental liabilities and convert economic losses to useful by-products using innovative methods to de-oil, de-scale, and de-salt produced water.