High-temperature membrane distillation

A system for separating a distillate fluid from a feed solution, the system comprising:

• a feed loop for providing a supply of the feed solution, the feed loop comprising:
• at least one heat exchanger configured to heat the supply of the feed solution to an elevated temperature that is greater than an atmospheric-pressure boiling temperature of the feed solution;
• and
• at least one fluid pump configured to pressurize the supply of the feed solution to an elevated pressure at which an effective boiling temperature of the feed solution is greater than the elevated temperature;
• a distillate loop for providing a supply of the distillate fluid;
• and
• at least one membrane module comprising:
• an outer casing having an interior region;
• and
• a plurality of hollow fiber membranes extending through at least a portion of the interior region, the plurality of hollow fiber membranes separating the at least one membrane module into a shell side and a tube side, wherein the shell side is in fluid communication with the feed loop and the tube side is in fluid communication with the distillate loop, and wherein the elevated pressure is less than a liquid penetration pressure of the plurality of hollow fiber membranes.

A method for separating a distillate fluid from a feed solution, the method comprising:

• heating the feed solution to an elevated temperature that is greater than an atmospheric-pressure boiling temperature of the feed solution;
• pressurizing the feed solution to an elevated pressure at which an effective boiling temperature of the feed solution is greater than the elevated temperature;
• introducing the heated and pressurized feed solution to a membrane module comprising a plurality of hollow fiber membranes, wherein the elevated pressure is less than a liquid penetration pressure of the plurality of hollow fiber membranes;
• forming vapor pressure differentials across the plurality of hollow fiber membranes;
• and
• separating the distillate fluid from the feed solution by the formed vapor pressure differentials.