Methods for controlling stored urine odor in resource-oriented sanitation

Urine odor is a major challenge in the development of resource-oriented sanitation (ROS). One common solution to overcome odor issues is to use energy-consuming ventilation practices. However, historically ancient Koreans practiced separation of urine and feces, followed by the collection and utilization of gathered sanitary matters. Furthermore, ancient Persians developed solutions to urine odor issues. This study investigates the role of NH3 concentration on odor production in stored urine using the standard threshold odor number (TON) measurement. Trends in pH and NH3 production, as well as their interactions with TON, were investigated by simulating ancient Korean practices that stored urine under anaerobic conditions at different temperatures. The results show a direct relationship between the concentrations of NH3 and TON. Storing urine under anaerobic conditions leads to the production of NH3, which intensifies as temperature increases. The effect of pH and NH3 concentrations on the TON of stored urine explains the ancient Persian approach, given that additives, such as acetic acid and sodium bicarbonate, are effective for removing urine odor. Such approaches can be successfully applied to ROS systems.