For long duration space travel to be practical, regenerative life support capabilities are needed for continual recycling of system resources, including waste streams (urine and wastewater). Nutrient recycling is essential to providing important nutrients and fertilizer for plants. NASA seeks approaches for using in situ waste streams for this purpose. InnoSense LLC (ISL) will develop ACSUMOP™ (Acicular Surface Modified Polymers). ACSUMOP will promote faceted sodium chloride (NaCl) crystal growth and its separation from urine and wastewater in the Environmental Control and Life Support Systems (ECLSS) loop. To demonstrate the feasibility in Phase I, ISL will: (1) synthesize and characterize ACSUMOP with varying surface chemistries and morphology and apply as coating on a plastic surface, (2) study the parameters that influence NaCl crystallization on the ACSUMOP surface, (3) demonstrate temperature invariance of NaCl extraction from a solution of mixed salts, (4) measure the crystal sizes and zeta potential of the solutions, and (5) develop and evaluate an ACSUMOP breadboard to extract NaCl and regenerate it using simple mechanical means. In Phase II, ISL will optimize performance of ACSUMOP by: (1) optimizing the surface chemistry of ACSUMOP to improve selectivity to NaCl and durability under operating conditions, (2) evaluating the crystallization rate and solubility control under practical operating conditions in space, (3) scaling up for a 10 L wastewater tank, and (4) developing the automated system to insert, extract and recover the crystallized NaCl regenerating ACSUMOP for reuse. An engineering delivery unit (EDU) level prototype will be delivered to NASA for evaluation and eventual space qualification following Phase II.
ACSUMOP will be a NASA-relevant approach for treating waste streams allowing retrieval of the remaining solid wastes for use as plant fertilizer. The regeneration aspect of ACSUMOP will be conducive to minimizing spent-waste during long-during missions. Spin-off applications can be developed for extracting a variety of mineral nutrients from waste stream.
ACSUMOP can be used to support global water and wastewater treatment. Markets include treatment technologies and related chemicals, delivery equipment and instrumentation (e.g., anaerobic digesters, activated sludge instrumentation, nutrient removal instrumentation, and sedimentation sensors, etc.), for municipal and industrial applications.