Description: In situ resource utilization (ISRU) is essential for several of NASA's future flagship missions. Currently envisioned ISRU plants include production of oxygen from hydrogen reduction of lunar regolith and extraction of water from Martian regolith or asteroid material. These ISRU processes require heating of the regolith to high reaction temperatures. Once the reaction is complete, most thermal energy exits the system in the spent regolith batch and is therefore wasted. Creare proposes to recover this heat and use it to preheat fresh regolith prior to entering the reactor. Our novel heat recovery design is purely passive, robust, and compact to accommodate tight mass and volume constraints. Our heat exchanger promises to recover 80% of the otherwise wasted thermal energy. This energy savings can either be used to reduce the power plant size or speed up the production rates of the ISRU system. The Creare team has firsthand knowledge of the current ISRU research status and has the necessary background in mechanical design, heat exchanger design, as well as the facilities and commercialization expertise, to make this project a success.

Benefits: Many commercial processes involve the heating of particulate matter to high temperatures to affect a certain reaction, e.g., Portland cement kilns, drying processes in the agricultural and paper sectors, etc. As energy costs increase and with the focus on limiting green house gas emissions, more emphasis will be placed on improving the overall energy efficiency of such processes. Heat recovery methods using advanced heat exchangers such as the one proposed here could have a tremendous impact to improve this efficiency.

The main application area for NASA for the proposed heat exchanger for ISRU plants will be for future missions now being planned to Mars and the Moon, as well as other bodies such as Near Earth objects (NEOs). Long duration missions to the Moon will need substantial amounts of resources for life support and energy. Martian sample return missions and manned missions to Mars may be prohibitively expensive, technically exigent, and unacceptably risky unless resources can be produced on Mars. For example, NASA will need an ISRU propellant production plant on Mars for the sample return mission that it is envisioning in the 2020s.