Monday, 6 August 2018

Environmental impact of the Nano Membrane Toilet

The energy team have been hard at work developing their understanding the environmental impact of the Nano Membrane Toilet and have produced two papers recently.

The first is a probabilistic model to investigate the energy and environmental performance of the Nano Membrane Toilet.   It highlighted the potential of a Sterling Engine within the toilet, which could even give a net power output.   It would also emit less CO2 and NOx than conventional wastewater treatment.


The second performs a “Life Cycle Assessment”, comparing the Nano Membrane Toilet to a pour flush toilet and a urine diverting dry toilet implemented hypothetically in South Africa.   The UDDT had the best environmental performance due to the reuse of urine and faeces as fertilisers.   However, when human health was considered, the Nano Membrane Toilet performed best, because of the potential for electricity generation and the reduction of NOx emissions.


Friday, 3 August 2018

Recent developments in the components of the Nano Membrane Toilet

The team have been hard at work developing the components of the Nano Membrane Toilet and have produced three papers recently.

To separate clean water form urine, membrane distillation is used.   Good quality water was able to be produced, despite the high concertation of the urine.   Fouling was reversible using physical cleaning, without needing any additional pressure.   When faecal contamination was added to urine, it was still possible to reduce Chemical Oxygen Demand, but it would be better to have a pre-treatment stage to achieve the best water quality.

The final stage of faeces processing in the Nano Membrane Toilet is a micro-combustor.   This paper describes the initial successful tests of this component on real human faeces.


To recover energy from this combustion we have modelled the performance of a Sterling Engine which they have shown could produce a daily power output of 27 Wh/h.