NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Carbon Dioxide Removal via Passive Thermal ApproachesA paper describes a regenerable approach to separate carbon dioxide from other cabin gases by means of cooling until the carbon dioxide forms carbon dioxide ice on the walls of the physical device. Currently, NASA space vehicles remove carbon dioxide by reaction with lithium hydroxide (LiOH) or by adsorption to an amine, a zeolite, or other sorbent. Use of lithium hydroxide, though reliable and well-understood, requires significant mass for all but the shortest missions in the form of lithium hydroxide pellets, because the reaction of carbon dioxide with lithium hydroxide is essentially irreversible. This approach is regenerable, uses less power than other historical approaches, and it is almost entirely passive, so it is more economical to operate and potentially maintenance- free for long-duration missions. In carbon dioxide removal mode, this approach passes a bone-dry stream of crew cabin atmospheric gas through a metal channel in thermal contact with a radiator. The radiator is pointed to reject thermal loads only to space. Within the channel, the working stream is cooled to the sublimation temperature of carbon dioxide at the prevailing cabin pressure, leading to formation of carbon dioxide ice on the channel walls. After a prescribed time or accumulation of carbon dioxide ice, for regeneration of the device, the channel is closed off from the crew cabin and the carbon dioxide ice is sublimed and either vented to the environment or accumulated for recovery of oxygen in a fully regenerative life support system.
Document ID
20120000823
Acquisition Source
Johnson Space Center
Document Type
Other - NASA Tech Brief
Authors
Lawson, Michael
(NASA Johnson Space Center Houston, TX, United States)
Hanford, Anthony
(NASA Johnson Space Center Houston, TX, United States)
Conger, Bruce
(NASA Johnson Space Center Houston, TX, United States)
Anderson, Molly
(NASA Johnson Space Center Houston, TX, United States)
Date Acquired
August 25, 2013
Publication Date
July 1, 2011
Publication Information
Publication: NASA Tech Briefs, July 2011
Subject Category
Man/System Technology And Life Support
Report/Patent Number
MSC-24445-1
Distribution Limits
Public
Copyright
Public Use Permitted.
No Preview Available