The Resource Circulation Sanitation (RCS) System
Showcasing the Provision of Sustainable Sanitation in Remote Areas
Sanitation is a global challenge. In particular, rural and remote communities, which their economic development is heavily related to agriculture, are generally facing a lack of access to appropriate sanitation. Consequently, the sixth sustainable development goal (SDG6) is aiming sustainable access to adequate sanitation for all.
Meanwhile, during the years 2018 to 2019, the United Nations has emphasized developing nature-based solutions (NBS) to provide sustainable access to water and sanitation for all, leaving no one behind. In 2018, the World Health Organization (WHO) published guidelines on sanitation and health systems.
Using common flush type toilets cannot be a sustainable solution for remote and rural areas. They consume a high amount of water, require complicated infrastructure, and produce wastes.
Accordingly, an innovative sanitation system named as “Resource Circulated Sanitation (RCS)” has been developed by Dr. Shervin Hashemi, and supported with scaled-up showcase projects objecting to investigate the technical efficiency and sustainability of the system for offering public hygiene services in a remote area.
The system includes a dry toilet seat, urine reactor, feces reactor, and rainwater harvesting system to provide water for sanitary proposes. The toilet seat efficiently separates urine from feces, storing them in their reactors. Urine is stored in a tank-in-series reactor, while feces, along with other hygienic materials, such as biodegradable toilet papers, are led into a batch reactor including sawdust for the composting process. The reactors are well-designed based on the estimated amount of usage and retention time of 10 to 15 days.
The nature-based treatment process includes adding a microflora, containing nitrifying microorganisms, to urine and feces reactors. The nitrification process gives benefits for reducing the stabilization time for urine and enhancing the biodegradation of feces.
This treatment also shows efficiency in increasing the fertilizing potential of urine by modifying its nitrogen profile. Moreover, pH reduction as a result of nitrification led to reducing ammonia losses as gas along with odor production. Furthermore, this method was useful in the efficient removal of fecal indicators.
Water for sanitation purposes is provided through a rainwater harvesting system. The produced greywater is treated onsite to be used for irrigation purposes. A trained management committee sustains the operation and maintenance of the system.
The treated wastes showed higher agronomic productivity comparing to a locally available commercial fertilizer through cultivating white radish.
The system is sustainable due to its efficiency in reducing water and energy consumption, along with recycling urine and feces to be utilized as fertilizer. The benefits acquired by fertilizer production, water-saving, and higher agricultural productivity are substantial, indicating the potentials for improving the economy of the community, where the system is implemented.
This system meets the recommendations of WHO guidelines, does not need complicated infrastructure, and provides NBS for sanitation problems, make it suitable for remote areas. No direct contact with sanitary wastes makes the system safe, preventing the spread of infections like COVID19. Consequently, it can be considered as a step ahead toward SDGs 1, 2, and 6. The system is recognized for several international awards, including the “Excellent Award of World Water Challenge 2017,” “Leaving No One Behind Innovation Award 2019,” and “Energy Globe Republic of Korea National Award 2019.” More information about the details of the RCS system can be found in this link.