A method of a filtration uses a hollow fiber membrane module comprising a module case; and a hollow fiber membrane bundle comprising a plurality of hollow fiber membranes bundled together and being accommodated in the module case, respective ends of the hollow fiber membranes being bonded together by a potting material. The filtration is carried out in the hollow fiber membrane module under a pressure of 0.3 to 1.2 MPa. The hollow fiber membrane module satisfies a relationship: 0.5<R/L<5 when the pressure inside the hollow fiber membrane module is 1.0 MPa without the hollow fiber membrane module being restrained, and satisfies relationships: 0<R<0.25 and 0<L<0.06 during an operation in an operation condition, where R (%) represents a radial expansion ratio at a center portion in a longitudinal direction, and L (%) represents a longitudinal expansion ratio, of the hollow fiber membrane module.

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 membrane distillation apparatus includes a housing and an impeller. The housing includes a hot medium compartment, a cold medium compartment, a permeate 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 permeate 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 permeate gap compartment includes a permeate outlet configured to discharge the condensed water vapor. The impeller is disposed within the permeate gap compartment.

Certain disclosed embodiments concern systems and methods of preparing dialysate for use in a home dialysis system that is compact and light-weight relative to existing systems and consumes relatively low amounts of energy. The method includes coupling a household water stream to a dialysis system; filtering the water stream; heating the water stream to at least about 138 degrees Celsius in a non-batch process to produce a heated water stream; maintaining the heated water stream at or above at least about 138 degrees Celsius for at least about two seconds; cooling the heated water stream to produce a cooled water stream; ultrafiltering the cooled water stream; and mixing dialysate components into the cooled water stream in a non-batch process.

Certain disclosed embodiments concern systems and methods of preparing dialysate for use in a home dialysis system that is compact and light-weight relative to existing systems and consumes relatively low amounts of energy. The method includes coupling a household water stream to a dialysis system; filtering the water stream; heating the water stream to at least about 138 degrees Celsius in a non-batch process to produce a heated water stream; maintaining the heated water stream at or above at least about 138 degrees Celsius for at least about two seconds; cooling the heated water stream to produce a cooled water stream; ultrafiltering the cooled water stream; and mixing dialysate components into the cooled water stream in a non-batch process.

A process to treat water includes adding a salt-forming base to the water thereby producing saline water, or thereby forming a salt in the water which is different from a salt that the water started out with, if the water started out as saline. The saline water is treated, at a temperature T1 which is above the saturation temperature of the saline water, in a first membrane separation stage to provide clean water and a first brine, the salinity of the first brine being higher than the salinity of the saline water. The first brine is cooled to a temperature T2 to precipitate some of the salt from the first brine and the precipitated salt is separated from the first brine producing a second brine, the temperature T2 being below the temperature T1 but above the freezing temperature of the first brine. The second brine is treated at a temperature T3 above the saturation temperature of the second brine in a second membrane separation stage to provide clean water and a third brine. The salt-forming base, the temperature T1 and the temperature T2 are selected so that the salt which is formed in the saline water has a solubility in water at the temperature T1 which is at least 1.5 times the solubility of the salt in water at the temperature T2.

Embodiments of the present disclosure include a system for optimizing dirty water remediation and re-use. The system can include a first treatment system that includes a direct contact thermal distillation system or an evaporator. The system can further include a frac water re-use treatment system.

The reverse osmosis system with at least one high pressure pump, which supplies untreated water to at least one module pipe, in which a membrane with a permeate collecting pipe is arranged, includes a permeate outlet of the at least one module pipe that is connected by means of a first conduit to a permeate tank, which is in communication by means of a further conduit, connected into which there is a permeate supply pump, with a loop feed line, to which a plurality of dialysis devices are connected and that branching off from the first conduit there is a bypass conduit, which discharges into the further conduit downstream of the permeate tank and the permeate supply pump.

The reverse osmosis system with at least one high pressure pump, which supplies untreated water to at least one module pipe, in which a membrane with a permeate collecting pipe is arranged, includes a permeate outlet of the at least one module pipe that is connected by means of a first conduit to a permeate tank, which is in communication by means of a further conduit, connected into which there is a permeate supply pump, with a loop feed line, to which a plurality of dialysis devices are connected and that branching off from the first conduit there is a bypass conduit, which discharges into the further conduit downstream of the permeate tank and the permeate supply pump.

A microporous membrane has average membrane thickness of 15 μm or less, and relative impedance A after a heat compression treatment under a pressure of 4.0 MPa at 80° C. for 10 minutes of 140% or less, the relative impedance A being obtained by the equation below: Relative impedance A=(impedance measured at 80° C. after the heat compression treatment)/(impedance measured at room temperature prior to the heat compression treatment)×100.