Criteria Definition and Performance Testing of a Space Station Experiment Water Management System

Recently, interest has developed for a process to reclaim waste water from experiments in the Space Station United States Laboratory (USL). The need for a water recovery system has been generated from a growing list of experiments proposed for the Space Station that will require ultrapure water. These proposed experiments will require water that meets both USP XXI and the ASTM proposed Electronics Grade Specifications. This high quality water may be produced by a hybrid of new technologies and by water subsystems currently considered for Environmental Control and Life Support on the Space Station.

To evaluate these water recovery systems and other technologies, a testing program was conducted to challenge individual water recovery subsystems with waste solutions from experiments typical of those that will be a part of the USL. The water recovery systems are being evaluated based on the permeate water quality. Samples of the permeate and of the concentrated waste solutions are taken during each test and analyzed for endotoxins, microbes, pH, conductivity and Total Organic Carbon (TOC). Some permeate samples were also analyzed for specific inorganics, organics, and Total Dissolved Solids.