A Solid-State Compressor for Integration of CO ₂ Removal and Reduction Assemblies

Oxygen loop closure is of high priority for an advanced space station air revitalization system. Closure will require the system's CO₂ removal and reduction assemblies to be linked; however, the hardware for these two assemblies that is presently considered for use on the International Space Station (ISS) cannot be connected directly and so an interface device is needed. The interface device must provide an adequate vacuum for the CO₂ removal assembly, must provide CO₂ at a high enough pressure for the CO₂ reduction assembly, and must also store sufficient CO₂ to accommodate the difference in operating periods of the two processes. A mechanical vacuum pump/compressor with a buffer tank is one solution to the interface, but has drawbacks particularly in the areas of power consumption and size.

A solid-state, adsorption-based compressor design is being developed at NASA Ames Research Center that meets the requirements of the interface device. The design appears to offer several advantages over mechanical solutions. This article describes the basis for a temperature-swing adsorption compressor and one possible implementation of the device for potential application on the ISS.