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This project will study the use electrostatics to perform electrostatic separation and recovery of Environmental Control and Life Support Systems (ECLSS) waste brines. Currently we have no way to perform nutrient recovery on ECLSS waste brines. This process can give us a competing way to separate sodium from potassium to allow tandem production of acids, bases, and plant fertilizers to run upstream operations and hydroponic systems respectively (when combined with electrodialysis). If we can recover valuable chemicals from brine, then this will decrease resupply from earth, which will allow tremendous (multiple kilograms a day up-mass reduction) cost savings. In addition, using electrostatics for regolith enrichment allow much reduced mining costs for metal production on celestial bodies and allow a smaller mining footprint.

Natural lightning and the associated clouds are known to behave differently over land and ocean, but many questions remain. We expand the related observational datasets by obtaining simultaneous quasi-static electric field observations over coastal land, near-shore water, and deep ocean regions during both fair-weather and thunderstorm periods. Oceanic observations were obtained using two 3-m NOAA buoys that were instrumented with Campbell Scientific electric field mills to measure the quasi-static electric fields. These data were compared to selected electric field records from the existing on-shore electric field mill suite of 31 sensors at Kennedy Space Center (KSC). Lightning occurrence times, locations and peak current estimates for both onshore and ocean were provided by the U.S. National Lightning Detection Network. The buoy instruments were first evaluated on-shore at the Florida coast, and the first system was calibrated for field enhancements and to confirm proper behavior of the system in elevated-field environments. The buoys were then moored 20 mi and 120 mi off the coast of KSC in February (20 mi) and August (120 mi) 2014. Diurnal fair-weather fields at both ocean sites matched will with each other and with those found during the Carnegie cruise, but mean values were 33% smaller, due at least in-part to constraints on the calibration procedure. Diurnal fair-weather fields variations at coastal and inland sites were a poorer match than offshore, likely because the offshore environment is “cleaner” with limited variations in local space charge, lower surface aerosol densities, little surface heating to disturb the surface charge layer during fair weather, and fewer local radioactive sources to modulate the near-surface electrical conductivity. Storm-related static fields were 4-5× larger at both oceanic sites than over land, likely due to decreased screening by near-surface space charge produced by corona current. The time-evolution of the electric field and field changes during storm approach are sufficiently different over land and ocean to warrant further study. This work shows the quality, accuracy, and reliability of these data, and has demonstrated the practicality of off-shore electric field measurements for safety- and launch-related decision making at KSC.

This project is a follow-on work to a Science Innovation Fund (SIF) project to develop a new form of Paschen’s law that could relax current triboelectrification launch criteria by considering the effect of the flow of gas past aerospace vehicle surfaces. Paschen’s law, derived in 1889 by F. Paschen, calculates the minimum voltage required to create an electrical spark or discharge between two electrodes.