Final Project Report-11123-03-The objective of this project was to upscale the humidification dehumidification (HDH) process tested successfully at field scale in RPSEA Project 07123-05, “Cost-Effective Treatment of Produced Water Using Co-Produced Energy Sources for Small Producers,” and to demonstrate a viable and cost effective process using solar energy or waste heat to augment the process for continuous operation. Increased automation and maintenance parameters were evaluated and put in place to allow unattended operation for several days or even weeks at a time and a full-scale prototype was constructed and operated at a field gathering site for a period of four months with the goal of reducing disposed water to less than 20% of the original volume. Technology transfer efforts focused on commercialization of the technology