Anaerobic stabilisation of urine diverting dehydrating toilet faeces (UDDT-F) in urban poor settlements

Anaerobic stabilisation of urine diverting dehydrating toilet faeces (UDDT-F) in urban poor settlements: Biochemical energy recovery

Riungu, J. (IHE Delft Institute for Water Education)
Ronteltap, Mariska (IHE Delft Institute for Water Education)
van Lier, J.B. (TU Delft Sanitary Engineering; IHE Delft Institute for Water Education)

2019

Biochemical energy recovery using digestion and co-digestion of faecal matter collected from urine diverting dehydrating toilet faeces (UDDT-F) and mixed organic market waste (OMW) was studied under laboratory-and pilot-scale conditions. Laboratory-scale biochemical methane potential (BMP) tests showed an increase in methane production with an increase in OMW fraction in the feed substrate. In subsequent pilot-scale experiments, one-stage and two-stage plug flow digester were researched, applying UDDT-F:OMW ratios of 4:1 and 1:0, at about 10 and 12% total solids (TS) slurry concentrations. Comparable methane production was observed in one-stage (R_o-4:1,12%) (314 ± 15 mL CH₄/g VS added) and two-stage (R_am-4:1,12%) (325 ± 12 mL CH₄ /g VS added) digesters, when applying 12% TS slurry concentration. However, biogas production in R_am-4:1,12% digester (571 ± 25 mL CH₄/g VS added) was about 12% higher than in R_o-4:1,12%, significantly more than the slight difference in methane production, i.e. 3–4%. The former was attributed to enhanced waste solubilisation and increased CO₂ dissolution, resulting from mixing the bicarbonate-rich methanogenic effluent for neutralisation purposes with the low pH (4.9) influent acquired from the pre-acidification stage. Moreover, higher process stability was observed in the first parts of the plug flow two-stage digester, characterised by lower VFA concentrations.

Anaerobic digestion
Biogas production
Co-digestion
Informal settlements
UDDT faeces

http://resolver.tudelft.nl/uuid:c92248e8-8727-4242-8ca6-82c065c55089

https://doi.org/10.2166/washdev.2019.099

2043-9083

Journal of Water, Sanitation and Hygiene for Development, 9 (2), 289-299

Institutional Repository

journal article

© 2019 J. Riungu, Mariska Ronteltap, J.B. van Lier