Design and commissioning of a multi-mode prototype for thermochemical conversion of human faeces

Jurado, Nelia; Somorin, Tosin; Wagland, Stuart T.; Patchigolla, Kumar; Parker, Alison; McAdam, Ewan J.; Williams, Leon; Tyrrel, Sean

doi:10.1016/j.enconman.2018.02.065

Cited by 16 publications

(13 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The higher average activation energy of HF can be attributed to the highly bound nature of the material. HF is a by-product of digestion and a blend of undigested food materials, microbial biomass, digestive juices and secretions, along with soluble and insoluble nutrients including fats, protein, water and polysaccharides [33]. These materials have gone through complex processes —evolving from ingestion, mechanical and chemical digestion, absorption to compaction of the waste.…”

Section: Resultsmentioning

confidence: 99%

Non-isothermal thermogravimetric kinetic analysis of the thermochemical conversion of human faeces

et al. 2019

View full text Add to dashboard Cite

The “Reinvent the Toilet Challenge” set by the Bill & Melinda Gates Foundation aims to bring access to adequate sanitary systems to billions of people. In response to this challenge, on-site sanitation systems are proposed and being developed globally. These systems require in-situ thermal treatment, processes that are not well understood for human faeces (HF). Thermogravimetric analysis has been used to investigate the pyrolysis, gasification and combustion of HF. The results are compared to the thermal behaviour of simulant faeces (SF) and woody biomass (WB), along with the blends of HF and WB. Kinetic analysis was conducted using non-isothermal kinetics model-free methods, and the thermogravimetric data obtained for the combustion of HF, SS and WB. The results show that the devolatilisation of HF requires higher temperatures and rates are slower those of WB. Minimum temperatures of 475 K are required for fuel ignition. HF and SF showed similar thermal behaviour under pyrolysis, but not under combustion conditions. The activation energy for HF is 157.4 kJ/mol, relatively higher than SS and WB. Reaction order for HF is lower (n = 0.4) to WB (n = 0.6). In-situ treatment of HF in on-site sanitary systems can be designed for slow progressive burn.

show abstract

Section: Resultsmentioning

confidence: 99%

Non-isothermal thermogravimetric kinetic analysis of the thermochemical conversion of human faeces

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The mechanical flush is part of the Nano Membrane Toilet (NMT) project at Cranfield University (Parker, 2014). The NMT is being developed as a standalone, non-sewered, household-level sanitation system that separates solid and liquid wastes (Mercer et al, 2016) and treats them in combustion (Jurado et al, 2018) and membrane processes (Wang et al, 2017) respectively. While a complex technological solution like the NMT could solve a variety of other issues surrounding the storage, transport and treatment of faecal sludge (Strande, 2014), the mechanical flush can be implemented independently, into already existing sanitation systems like pit latrines, chemical toilets, camping, or composting toilets.…”

Section: Discussionmentioning

confidence: 99%

Field testing of a prototype mechanical dry toilet flush

Hennigs

Ravndal

Blose

et al. 2019

Science of The Total Environment

Self Cite

View full text Add to dashboard Cite

A prototype of a non-fluid based mechanical toilet flush was tested in a semi-public, institutional setting and in selected peri-urban households in eThekwini municipality, Republic of South Africa. The mechanism's functionality and users' perception of the flush were assessed. User perception varied depending on background: Users accustomed to porcelain water flush toilets were open to, yet reserved about the idea of using a waterless flush in their homes. Those who commonly use Urine Diversion Dehydration Toilets were far more receptive. The user-centred field trials were complemented by a controlled laboratory experiment, using synthetic urine, -faeces, and -menstrual blood, to systematically assess the efficiency of three swipe materials to clean the rotating bowl of the flush. A silicone rubber with oil-bleed-effect was found to be the best performing material for the swipe. Lubrication of the bowl prior to use further reduced fouling. A mechanical waterless flush that does not require consumables, like plastic wrappers, is a novelty and could – implemented in existing dry toilet systems – improve acceptance and thus the success of waterless sanitation.

show abstract

“…The system is capable of delivering treated wastewater and excess amount of energy, which can be used in the form of electricity for household needs. A comprehensive description of the NMT system is provided in the referenced research studies ( Hanak et al, 2016 ; Onabanjo et al, 2016a ; Kolios et al, 2018 ; Jurado et al, 2018 ).…”

Section: Methodsmentioning

confidence: 99%

Conceptual environmental impact assessment of a novel self-sustained sanitation system incorporating a quantitative microbial risk assessment approach

Anastasopoulou

Kolios

Sowale

et al. 2018

Science of The Total Environment

Self Cite

View full text Add to dashboard Cite

In many developing countries, including South Africa, water scarcity has resulted in poor sanitation practices. The majority of the sanitation infrastructures in those regions fail to meet basic hygienic standards. This along with the lack of proper sewage/wastewater infrastructure creates significant environmental and public health concerns. A self-sustained, waterless “Nano Membrane Toilet” (NMT) design was proposed as a result of the “Reinvent the Toilet Challenge” funded by the Bill and Melinda Gates Foundation. A “cradle-to-grave” life cycle assessment (LCA) approach was adopted to study the use of NMT in comparison with conventional pour flush toilet (PFT) and urine-diverting dry toilet (UDDT). All three scenarios were applied in the context of South Africa. In addition, a Quantitative Microbial Risk Assessment (QMRA) was used to reflect the impact of the pathogen risk on human health. LCA study showed that UDDT had the best environmental performance, followed by NMT and PFT systems for all impact categories investigated including human health, resource and ecosystem. This was mainly due to the environmental credits associated with the use of urine and compost as fertilizers. However, with the incorporation of the pathogen impact into the human health impact category, the NMT had a significant better performance than the PFT and UDDT systems, which exhibited an impact category value 4E + 04 and 4E + 03 times higher, respectively. Sensitivity analysis identified that the use of ash as fertilizer, electricity generation and the reduction of NOx emissions were the key areas that influenced significantly the environmental performance of the NMT system.

show abstract

Design and commissioning of a multi-mode prototype for thermochemical conversion of human faeces

Cited by 16 publications

References 27 publications

Non-isothermal thermogravimetric kinetic analysis of the thermochemical conversion of human faeces

Non-isothermal thermogravimetric kinetic analysis of the thermochemical conversion of human faeces

Field testing of a prototype mechanical dry toilet flush

Conceptual environmental impact assessment of a novel self-sustained sanitation system incorporating a quantitative microbial risk assessment approach

Contact Info

Product

Resources

About