Multi-year Operation of the Organic Processor Assembly for the Treatment and Resource Recovery from Fecal Waste

Recognizing the need for a sustainable and closed-loop approach to fecal waste management in lunar habitats, an organic processor assembly (OPA) was developed by the University of South Florida and NASA’s Kennedy Space Center. The OPA is a hybrid treatment technology which couples the high-performance of membrane ultrafiltration with anaerobic digestion for the breakdown and conversion of organic solids. The OPA is designed to treat and recover resources from the fecal waste generated by a crew of four astronauts on an early planetary base. Design aspects and water quality data of the OPA’s early operations on canine fecal waste as surrogate to human waste were presented at ICES 2022. Nutrient-rich permeate produced from the treated and ultrafiltered canine fecal waste was collected and used in a hydroponics system where its nutrient composition successfully supported the growth of extra dwarf Bok Choy. Preliminary data from two grow-outs were presented at ICES 2023. This conference paper will highlight the long-term stability and robustness of the OPA by examining the system’s ability to resume treatment after an extended dormancy period of approximately one year. This conference paper will present data on the OPA’s overall long duration (>1000 days) treatment of canine fecal waste and permeate water quality, with emphasis on post-dormancy operations and system response to dormancy. Overall, the OPA is an enabling technology capable of managing fecal waste over an extended period, minimizing fecal storage volume, and contributing to closing nutrient cycles on early planetary habitats.