Decentralized sanitation system based on vacuum collection and reuse of excreta and kitchen waste

Purpose

To build up a more affordable and sustainable sanitation mode which bases principally on vacuum collection of domestic wastes (excrements and kitchen wastes) and reuse them as fertilizer in China.

Activities

Helped by the 10,000$ from the Bill & Melinda Gates’ Foundation, we built a demonstrate engineering located in Chentang Village, Changsu City, Jiangsu Province in China. The engineering contains 41 vacuum toilets, 750m-length pipeline, a pump-station with a 24m3 tank for storing the blackwater and has served for 23 families over 2 years. The total engineering cost is 430,000 RMBs (~66,000$), which is not more expensive than the traditional system. A prototype vacuum collector for colleting heavy kitchen wastewaters and wastes was also tested in laboratory. If it being integrated into the vacuum sewage system, 80% of the challenges as well as the costs of the domestic wastes disposal will be saved. Recently cooperated with the villager committee, a 0.5-hectre plantation that only uses organic fertilizer was put into operation near by the pump-station. It was estimated 1267 m3 tap water and 5840 KWh energy was saved per year, comparing with the traditional water flush sanitary and wastewater treatment.

Whether the vacuum sanitation appliances and sewage system can serve for thousands and millions of people is not determined by the engineering cost, since the manufacturing cost of the vacuum appliances and equipments is expected to cut off 2/3 when large-scale use. The vacuum sanitation mode means a novel industrial chain with five links: vacuum manufacturing, engineering service, system maintaining service, organic fertilizer produce and usage. How to chain the five links and get policy support is the main challenge we face to.

Countries of activity

Location of main activity

Objectives

Build up a pilot scale verification system and fulfill the preliminary technical and economical feasibility study.

Further information

Research or implementation partners: Bureau of housing and urban-rural development of Changsu city (Jiangsu Province, China); Jiangsu town & village water technology service company.

Filter tags

Bill & Melinda Gates Foundation East Asia & Pacific Greywater or wastewater Product design and engineering Resource recovery Specific to one or several countries Treatment of wastewater or greywater Urban (entire city)

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