2014 Nicolau Evaluation of a Urea Bioelectrochemical System for Wastewater Treatment Processes
Due to the high cost of delivering supplies to space, the recovery of potable water from spacecraft wastewater is critical for life support of crewmembers in short- and long-term missions. It is estimated that in future long-term space missions, human wastes such as urine will contribute more than 50% of the total waste. Thus, we will demonstrate how unused components, such as urea, can be recovered and reused in wastewater recycling processes. In this system, a urea bioreactor (GAC-urease) converts urea to ammonia. Then, an electrochemical cell converts the ammonia to power. The combined system is referred to as the Urea Bioreactor Electrochemical (UBE) unit. The results of this research showed the feasibility of interfacing wastewater-recycling processes with bioelectrochemical systems to achieve water recycling while reusing useful resources. The UBE systems removed >80% of organic carbons and converted approximately 86% of the urea to ammonia. Therefore, the concept herein proposed has the potential to be used in water recycling applications with emphasis in contaminant recovery from wastewater for useful resources and energy.
KEYWORDS: Resource recovery, Water reclamation, Urea degradation, Electrochemical cell, Bioreactor