A process treats high temperature produced water by passing a stream to an electrocoagulation unit and then to a membrane distillation (MD) unit where the stream contacts a hydrophobic membrane on a feed side and deionized water contacts the membrane on a product side. A distilled water stream is recovered and collected with the product side stream to form a volume-depleted exit produced water stream on the feed side of the hydrophobic membrane. The exit product side stream is passed through a heat exchanger to form a stream that is returned to a location upstream of the MD unit for an additional pass through the MD unit, thereby recovering additional water. The stream can be returned multiple times to achieve high recovery and to form a final stream leaving the MD unit having a temperature from 40-60 ° C., a total oil and grease content no greater than 500 mg/L, and a suspended solids content no greater than 200 mg/L. A portion of the distilled water stream from the membrane distillation unit can be used to form a brine solution used to regenerate used ion exchange resin in a water softening system.