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A new waste collection system (WCS) is undergoing development for use in the extended duration orbiter (EDO). Requirements for missions up to 18 days and the capability for missions up to 30 days necessitate the development of a new WCS that will have the appropriate capacity. The new system incorporates design features from both Skylab and Space Shuttle Orbiter WCSs. For urine collection, airflow is used to entrain the fluid and transport it to the phase separator where it is separated from the airflow and pumped to the waste water tank. For fecal collection, airflow is used to transport the waste into a collection bag. After use, a plastic lid is installed on the bag, and the bag and contents are compacted. The system for EDO utilizes redundant fans and urine separators. Plans call for the new WCS to be implemented for OV-105 (Endeavor) as well as for EDO. This paper describes the design and development status of the new WCS.

The recently developed Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES) offers a highly competitive approach to water recovery from waste fluids for future on-orbit stations such as the Space Operations Center. Low power, compactness and gravity insensitive operation are featured in this vacuum distillation subsystem that combines a hollow fiber membrane evaporator with a thermoelectric heat pump. The hollow fiber elements provide positive liquid/gas phase control with no moving parts other than pumps and an accumulator, thus solving problems inherent in other reclamation subsystem designs. In an extensive test program, over 850 hours of operation were accumulated during which time high quality product water was recovered from both urine and wash water at an average steady state production rate of 2.2 pounds per hour.

Recovery of high quality water from urine is an essential part of life support on a Space Station to avoid costly launch and resupply penalties. Water can be effectively recovered from urine by distillation following pretreatment by a chemical agent to inhibit microorganism contamination and fix volatile ammonia constituents. This paper presents the results of laboratory investigations of several pretreatment chemicals which were tested at several concentration levels in combination with sulfuric acid in urine. The optimum pretreatment formulation was then evaluated with urine in the Hamilton Standard Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES). Over 2,600 hours of test time was accumulated. Results of these laboratory and system tests are presented in this paper.

The Space Shuttle waste management system has undergone a variety of design changes to improve performance and man-machine interface. These design improvements have resulted in more reliable operation and hygienic usage. Design enhancements include individual urinals, increased urine collection airflows, increased solids storage capacity, easier access to personal hygiene items, and additional wet trash stowage. The development and flight evaluation of these improvements are described herein. The Space Shuttle Orbiter has proved to be an invaluable test bed for development and in-flight evaluation of life support and habitability concepts which involve transport or separation of solids, liquids, and gases in a zero-g environment.