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.

Anastasopoulou, A., Kolios, A., Somorin, T., Soale, A., Ying, J., Fidalgo, B.,Parker, A., Williams, L., Collins, M., MacAdam, S., Tyrrel, S., (2018) Conceptual environmental impact assessment of a novelself-sustained sanitation system incorporating a quantitative microbial riskassessment approach Science of The Total Environment, 639, 657-672

 

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.

Kolios,A.,  Ying, J., Somorin, T., Sowale, A.,Anastasopoulou, A., Anthony, E.J., Fidalgo, B., Parker, A., Williams, L.,Collins, M., MacAdam, S., Tyrrel, S., (2018) Probabilisticperformance assessment of complex energy process systems – The case of aself-sustained sanitation system, Energy Conversion and Management 163, 74-85

 

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.

F. Kamranvand, C. Davey, H. Sakara,, O. Autin,E. Mercer, M. Collins, L. Williams, A. Kolios, A. Parker, S. Tyrrel, E.Cartmell, E.J. McAdam (2018) Impact of fouling, cleaning and faecalcontamination on the separation of water from urine using thermally drivenmembrane separation. Separation Science and Technology

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.

Jurado, N., Somorin, T., Kolios, A.J.Email Author, Wagland, S.,Patchigolla, K., Fidalgo, B., Parker, A., McAdam, E., Williams, L., Tyrrel, S.,(2018) Design and commissioning of a multi-mode prototype for thermochemicalconversion of human faeces, Energy Conversion and Management 163, 507-524

 

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.

Sowale, A., Kolios, A.J.Email Author, Fidalgo, B., Somorin, T.,Parker, A., Williams, L., Collins, M., McAdam, E., Tyrrel, S. (2018)Thermodynamic analysis of a gamma type Stirling engine in an energy recoverysystem, Energy Conversion and Management, 165, 528-540