| abstract |
In some embodiments, systems and methods are provided for purifying a liquid, such as an impaired water. In some examples, seawater or brackish water is purified, such as to a potable level. Some configurations provide a system which includes a membrane-distillation unit, such as a vacuum-enhanced direct contact membrane distillation unit. The system also includes a forward-osmosis system, which may include one or more forward-osmosis units. A concentrated draw stream from the membrane-distillation unit, such as a concentrated brine solution, serves as a draw solution for a forward-osmosis unit, which may extract water from a source water, such as an impaired water. In some implementations, the forward-osmosis system includes a second forward-osmosis unit which uses the diluted draw solution from the first forward-osmosis unit as a draw solution to extract water from a source water. The system may include additional components, such as a heater or a buffer tank. |