An Optimized System for Advanced Multi-Effect Distillation (AMED) Using Waste Heat from Closed Gas Brayton Cycles

This report presents a novel Advanced Multi-Effect Distillation (AMED) method that can enable the production of substantial quantities of low-cost desalinated water using waste heat from high temperature reactors (HTRs). Conventional MED systems can currently compete with reverse osmosis desalination in areas where energy costs are relatively low, such as the Middle East. Because AMED can perform distillation without affecting the electricity generation efficiency of high temperature reactors (HTRs) using closed gas Brayton cycles, AMED can optimize to lower capital cost than conventional MED, while still producing large quantities of potable water. In examples presented here, a low-cost AMED system coupled to a 1200 MW(e) HTR plant (e.g., 4 GT-MHRs, 6 PBMRs, or 1 LS-VHTR) can produce 40,000 m/day of potable water. In locations where water costs are higher, additional effects may be added to increase water production up to 110,000 m/day or higher. AMED systems would use simple reconfiguration of current MED technology. While the additional AMED revenues (above electricity) are relatively modest (1 to 5%), the quantities of potable water generated as a byproduct of HTR electricity production are large, and could clearly be an important benefit for dry coastal regions.