Regenerable device for scrubbing breathable air of CO2 and moisture without special heat exchanger equipment

Abstract

Abstract The device concerns the circulation of cabin air through canisters which absorb and adsorb carbon dioxide, together with excess moisture, and return the scrubbed air to the cabin for recirculation. A coating on an inert substrate in granular form absorbs and adsorbs the impurities at standard temperatures and pressures, but desorbs such impurities at low pressures (vacuum) and standard temperatures. This fact is exploited by making the device in a stack of cells consisting of layers or cells which are isolated from one another flow-wise and are connected to separate manifolds and valving systems into two separate subsets. A first subset may be connected for the flow of breathable air therethrough until the polyethyleneimine of its cells is saturated with CO 2 and H 2 O. During the same period the second subset of cells is manifolded to a vacuum source. After the first period the first subset is re-valved to connect it to the vacuum system to draw off the collected impurities, while the newly purified subset B is connected to the breathable air of the cabin. These phases or half cycles are repeated, making it unnecessary to collect and discard any used-up materials. The cells of the device are separated from one another by sheets of a lightweight but impervious metal which is both physically strong and a good conductor of heat. To assist in the heat transfer process, a high conductivity foamed metal is disposed throughout the polyethyleneimine bed of each stratum, such foamed metal being formed into blocks which preferably touch both the upper and lower parting sheets defining the cell, to transfer heat to both the superior cell and the inferior cell so that the stack of cells operates essentially isothermally.

Inventors

• 👤 with respect to an invention of Fletcher James C. Administrator of the National Aeronautics and Space Administration
• 👤 Edward H. Tepper

Bibliographic Details