Microgravity Experimentation of Long Duration Space Mission Waste Conversion

The NASA Orbital Syngas / Commodity Augmentation Reactor (OSCAR) project is a 2 year project that aims to reduce risk of a space waste conversion system by demonstrating a microgravity reactor to advance NASA’s Trash-to-Gas efforts for mission waste reduction and conversion. On long duration deep space missions, humanity will be required to increase sustainability and efficiency on missions, which can be done by effectively managing logistical waste. The reuse of discarded materials on a long duration, deep space mission will reduce overall mission mass, increase usable spacecraft and habitat volume and improve mission reliability and robustness. On a 1 year mission, a four person crew will produce approximately 2,500 kg of waste materials consisting of food packaging, used clothing, hygiene items, human waste, life support system supplies, and other crew supplies. Repurposed waste can be safely vented off of a spacecraft in the form of an inert gas or useful material can be recovered such as fuel, air, water, and even feedstocks for spacecraft construction and repair. This paper will discuss the project development and results regarding the demonstration of a test article that will undergo microgravity tests at NASA’s 2.2-second Drop Tower, the Zero Gravity Research Facility, and on a several-minute commercial suborbital flight. Waste processing reactors will behave differently in reduced gravity with regards to the thermochemical process (ex: combustion), gas mixing, drying, solid entrainment behavior, and ash formation. The behavior of these situations in microgravity will be observed with OSCAR and results will be used to decide the appropriate method to model the system and to help guide the design of how air – or other oxidant – should be introduced into the hearth zone for optimum material conversion.