The Nano Membrane Toilet

Treating human waste onsite without external energy or water.

Cranfield University is developing the Nano Membrane Toilet, designed for single-household use (equivalent to 10 people). The toilet is designed to accept urine and faeces as a mixture. The toilet flush uses a unique rotating mechanism to transport the mixture into the toilet without demanding water whilst simultaneously blocking odour and the user’s view of the waste.

Solids separation (faeces) is principally accomplished through sedimentation. Loosely bound water (mostly from urine) is separated using low glass transition temperature hollow-fibre membranes. The unique nanostructured membrane wall facilitates water transport in the vapour state rather than as a liquid state which yields high rejection of pathogens and some odorous volatile compounds. A novel nano-coated bead enables water vapour recovery through encouraging the formation of water droplets at the nanobead surface. Once the droplets form a critical size, the water drains into a collection vessel for reuse at the household level in washing or irrigation applications.

Following release of unbound water, the residual solids (around 20-25% solids) are transported by mechanical screw which drops them into into a coating chamber lined with a replaceable bag. Once inside the coating chamber, the solid matrix is periodically coated with a biodegradable nano-polymer. The nanopolymer coating serves to block odour and acts as a barrier to pathogen transport. The toilet will be powered using a modular hand crank or bicycle power generator supplied for household use that can also power other low voltage items (e.g. mobile phones).

The replaceable bag comprising the coated solids is periodically collected for transport to a locally sited small scale gasifier sized to accommodate around 40 toilets. Both toilet maintenance and solids collection will be undertaken with a trained operative responsible for the franchised area.

On twitter



Fantastic week at the Natural History Museum

We had a fantastic week at the Natural History Museum as part of Universities Week.   Many of our visitors were shocked to learn how many people didn't have access to a toilet and were pleased we were doing something about it.&nbs...

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Posted 16th June 2014

Sharing the toilet with the Sharing Knowledge Foundation

We were delighted to be invited to speak about the Toilet at the 9th Sharing Knowledge Foundation Conference in Lisbon from 15th-17th May 2014.    The Sharing Knowledge Foundation was set up by Professors at CERN with a conce...

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Posted 10th June 2014

The Nano Membrane Toilet goes to the Natural History Museum

The Nano Membrane Toilet will form part of an exhibition for Universities Week 2014 at the Natural History Museum in London from 9 to 13 June.   Researchers from Cranfield University will join teams from 44 other UK universities ...

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Posted 29th May 2014

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