Innovators at NASA Glenn Research Center, in conjunction with Case Western Reserve University, have designed the Supercritical Water Oxidation - Flame Piloted Vortex (SCWO-FPV) Reactor that operates at temperatures and pressures above the thermodynamic critical point of water, enabling organic material to become highly soluble, effectively oxidizing all carbonaceous waste in liquid material introduced into the reactor.
The technology addresses problems that have long plagued SCWO-based systems by implementing an innovative design to limit temperatures on the reactor walls, minimizing the typical issues of scaling, corrosion, and fouling of heat transfer surfaces.
The reactor implements a unique design where heating is primarily supplied by the energetics of the waste stream through the control of a hydrothermal flame in the core of the reactor with the injection of fuel and oxidizer. Once the hydrothermal flame is initiated and stabilized, an outer-core “wash” stream, consisting primarily of water, is injected near the walls at the base of the reactor. This wash stream maintains subcritical conditions at the reactor walls, while also dissolving and/or flushing from the reactor any precipitate and non-soluble inorganic materials generated from the supercritical reactor core.
Mixing between the core region and the outer subcritical flow region is largely eliminated due to the great differences in density and viscosity. The flow configuration is further stabilized by the generation of a vortex using internal structures on the inside of the reactor wall. An aspirator assembly is positioned at the top of the supercritical core region to extract treated water and un-extracted material is recirculated through the reactor. The rate and amount of aspiration will be determined by product monitoring and will depend on waste stream content and overall operating conditions.