Performance Evaluation of a Three-Stage Vacuum Rotary Distillation Processor

Simulated spacecraft water recovery wastewater feed streams were purified with a three-stage vacuum rotary distillation processor (TVRD) during a series of tests conducted to evaluate the operation of this technology. The TVRD was developed to efficiently reclaim potable water from urine in microgravity by NIICHIMMASH (Moscow, Russia). A prototype was evaluated at the Honeywell Space Water Reclamation test lab, where a special test setup was assembled to evaluate the performance of the TVRD. This paper discusses the TVRD technology, test description, test results, and performance analysis.

Tests were conducted using four streams of wastewater: pretreated human urine, bioprocessor effluent, reverse osmosis brine ersatz, and deionized water. The testing demonstrated that greater than 90 percent water recovery can be reached with production rates of 2.2 to 2.9 kg/hr (4.84 to 6.30 lb/hr). Specific power consumption varied between 132 and 166 W-hr/kg (60 and 75 W-hr/lb), depending upon the wastewater stream being processed, making the TVRD the most efficient demonstrated distillation technology for space use. The product water was high quality with very low dissolved solids, and low in organic carbon. The evaluation test demonstrated reliable equipment performance and the versatility of the TVRD as a urine processor or as a secondary water processor.