Evaluation of Heat Recuperation in a Concentric Hydrogen Reduction Reactor

Abstract

Heat recuperation in an ISRU reactor system involves the recovery of heat from a reacted regolith batch by transferring this energy into a batch of fresh regolith. One concept for a hydrogen reduction reactor is a concentric chamber design where heat is transferred from the inner, reaction chamber into fresh regolith in the outer, recuperation chamber. This concept was tested and analyzed to define the overall benefit compared to a more traditional single chamber batch reactor. Data was gathered for heat-up and recuperation in the inner chamber alone, simulating a single chamber design, as well as recuperation into the outer chamber, simulating a dual chamber design. Experimental data was also used to improve two analytical models, with good agreement for temperature behavior during recuperation, calculated mass of the reactor concepts, and energy required during heat-up. The five tests, performed using JSC-1A regolith simulant, also explored the effectiveness of helium gas fluidization, hydrogen gas fluidization, and vibrational fluidization. Results indicate that higher hydrogen volumetric flow rates are required compared to helium for complete fluidization and mixing, and that vibrational fluidization may provide equivalent mixing while eliminating the need to flow large amounts of excess hydrogen. Analysis of the total energy required for heat-up and steady-state operations for a variety of conditions and assumptions shows that the dual-chamber concept requires the same or more energy than the single chamber concept. With no clear energy savings, the added mass and complexity of the dual-chamber makes it unlikely that this design concept will provide any added benefit to the overall ISRU oxygen production system.

Handbook of Research on Industrial Advancement in Scientific Knowledge

“…2. Resources Extraction: Several techniques envisaged for planetary ISRU are presented in literature to extract materials with the limited capabilities of space systems: carbothermic reduction (see Gustafson et al, 2010), reduction by hydrogen (see Linne at al., 2012), Molten regolith electrolysis (see Sibille at al., 2012). 3.…”

Feasibility studies for hydrogen reduction of ilmenite in a static system for use as an ISRU demonstration on the lunar surface

“…Previous studies, aimed specifically at ISRU capabilities, have used gas and/or vibrational fluidization techniques which improves mixing of the reactants and removal of the produced water (Christiansen et al, 1998;Gibson & Knudsen, 1985;Linne et al, 2009Linne et al, , 2012. A Significant limitation of the ProSPA system is that it is a static (nonflowing) and stationary (no fluidized bed or rotating drum) system, that utilizes a static volume of hydrogen gas.…”