The acquisition and storage of buffer gases (primarily argon and nitrogen) from the Mars atmosphere provides a valuable resource for blanketing and pressurizing fuel tanks and as a buffer gas for breathing air for manned missions. During the acquisition of carbon dioxide whether by sorption bed or cryo-freezer, the accompanying buffer gases build up in the carbon dioxide acquisition system, reduce the flow of to the bed, and lower system efficiency. It is this build up of buffer gases that provide a convenient source, which must be removed, for efficient capture of Removal of this buffer gas barrier greatly improves the charging rate of the acquisition bed and, thereby, maintains the fuel production rates required for a successful mission. Consequently, the acquisition, purification, and storage of these buffer gases are important goals of ISRU plans. Purity of the buffer gases is a concern e.g., if the freezer operates at 140 K, the composition of the inert gas would be approximately 21 percent 50 percent nitrogen, and 29 percent argon. Although there are several approaches that could be used, this effort focused on a hollow-fiber membrane (HFM) separation method. This study measured the permeation rates of nitrogen and argon (Ar) through a multiple-membrane system and the individual membranes from room temperature to 193 K and 10 kPa to 300 kPa. Concentrations were measured with a gas chromatograph. The end result was data necessary to design a system that could separate and Ar.
Buffer gas acquisition and storage
Space Technology and Applications International Forum - 2001 ; 2001 ; Albuquerque, New Mexico
AIP Conference Proceedings ; 552 , 1 ; 133-138
2001-02-02
6 pages
Conference paper
Electronic Resource
English