World's Biggest Urine Separating, Composting Toilet Scheme Fails

© EcoSanRes

In my post The History and Design of the Bathroom Part 8: Pulling It All Together, I called for the development of what I thought would be the perfect toilet; a combination of a composting toilet, a big basement collection tank serviced by third parties, and urine separation. I said such a toilet didn't exist; I was wrong. I does, it has been installed in multifamily dwellings, and it stinks.

They were developed by EcoSanRes of Sweden, and built in the town of Dongsheng, in northern China, which is going through a mineral-based economic boom. It has always had sanitation problems; 2/3 of the population uses public toilets, most of which are pit toilets and only 6% are flush. A demonstration project was started with a private developer, who was given a prime piece of land in exchange for building with the new toilets, developed by EcoSanRes and manufactured in China.

Urine is collected and stored on-site in under-ground brick and cement tanks made with local materials and subsequently used in local agriculture. Faecal material is retained in dry form in plastic bin containers, removed from the building basements and composted and sanitised along with household organics in the on- site ecostation for reuse as soil improvement. Thus, the community is offered sanitation services that work without water, while the water and nutrient cycles are being closed.

It did not quite work out as planned. Wu Shan reports in Chinadialogue. that the entire system has been ripped out and replaced with conventional flush toilets.

While the evidence of the world's biggest dry toilet experiment has been removed, the stench it created lingers in the memories of residents of the apartment complex in Ordos, Inner Mongolia. After three years of problems, the entire sewerage and wastewater handling system has been replaced and normal flushing toilets installed.

The toilets were not simple; there was some kind of rotating pot mechanism. You pulled a lever to add some sawdust and then the bowls would rotate and dump poop into a chamber below. Fans would draw air up to the roof to carry away smells, most if which actually come from the urine. One family describes the experience:

Yan's family just couldn't get used to it. The toilet smelled bad from day one, they said: there was a stench of ammonia throughout the house, sometimes enough to make their eyes water as soon as they stepped into the bathroom. "I could hardly eat at home, and felt miserable on my way back after work," said Yan. So the family usually ended up eating at Yan's sister's house. And their relatives didn't want to visit.

The excrement bowls, which need to rotate, started to break. Every single house had to have the bowls repaired, and in 60% of households they needed to be replaced frequently. In 2007, Yan's toilet was changed for one with a retractable tray, but the smells didn't improve.

In the end, everyone was pointing fingers at everyone, blaming the builder for quality problems, even the Stockholm Environment Institute. Finally the system was ripped out and replaced. "And so the world's largest dry toilet apartment complex disappeared, as if it had all been a dream." Read it all in ChinaDialogue.

Perhaps I should be re-thinking my bathroom of the future.

Tags: China | Composting Toilets

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