Biogas Systems

Content - Summary

Issue 9 contains the following three articles:

Digesting Faeces at Household Level - Experience From a “Model Tourism Village” in South India
Zurbrügg, C., Vögeli, Y., Estoppey, N.

Biogas Systems in Lesotho: an effective way to generate energy while sanitizing wastewater
Lebofa, M., Huba, E.

Evaluation of formulas to calculate biogas production under Moroccan conditions
Abarghaz, Y.,Mahi, M., Werner, C.,Bendaou, N., Fekhaoui, M.

++++++++++++

Digesting Faeces at Household Level - Experience From a “Model Tourism Village” in South India
Zurbrügg, C., Vögeli, Y., Estoppey, N.

The scope of the study was to assess the strengths and weaknesses of existing household level biogas systems treating toilet waste as well as organic kitchen waste. The biogas systems studied had been implemented on
Kumbalangi Island in South India within the framework of a Tourism Development Project to improve sanitary conditions. The assessment comprised a technical monitoring of two selected facilities over a period of two months as well as a household level users survey. Results reveal that the systems are working quite satisfactorily and are generating enough biogas to cook the main dishes of a family along with replacing most of the traditional cooking fuel. The treatment efficiency of the organic pollution is as good as to be expected from biogas systems.
However, the effluent does not match the legal requirements for use without any restrictions as organic fertilizer or for discharge into surface water bodies without any further treatment. The current investment costs are high as subsidies formerly provided are not available anymore. This severely limits the potential of wide spread replication.
++++++++
Biogas Systems in Lesotho: an effective way to generate energy while sanitizing wastewater
Lebofa, M., Huba, E.

This article describes Biogas as a decentralized wastewater treatment system implemented in Lesotho, where in 2002 a group of technicians, with strong interest in the link between environmental protection and human well-being, started to implement household biogas digesters for sanitation purposes in peri-urban settlements of the capital Maseru. The
demand for the technology is created by problems with overflowing or leaking septic tanks and high-priced drinking water commonly used for irrigation. No subsidy is provided, thus owners pay the real cost for the systems. Although the investment cost for BiogasDEWATS is a little higher than for a conventional septic tank, the operation costs are
significantly lower, plus it pays for itself in only three years. Biogas generated in these systems substitutes at least 15% of the daily required cooking fuel.
++++++++
Evaluation of formulas to calculate biogas production under Moroccan conditions
Abarghaz, Y.,Mahi, M., Werner, C.,Bendaou, N., Fekhaoui, M.

A biodigester was installed in Dayet Ifrah and connected to a farmer’s toilet and to a barn in June 2010. This is the first pilot unit built in Morocco used to produce biogas from anaerobic treatment of human excreta and animal slurries. The biogas produced is used as energy in cooking food and heating water. The entire biogas system works normally and
operates properly. But, after one year, the only problem we met is that the biogas production is low. The purpose of our study is to check if the weakness of the biogas volume is due to the dimensions of the biogas system. Our study confirms why biogas production is low. So, five other dimensioning formulas are evaluated and compared to the formula used
by GIZ. All formulas are compared and ranked by the ELECTRE III method and then by the sensitivity analysis. Results indicate that under Moroccan conditions Vedrenne’s formula (Vedrenne, 2007) is the most appropriate equation to calculate the biogas production in Moroccan context. In addition, the formula used in Dayet Ifrah over-estimated the
volume and the Vedrenne’s formula should be used.

Bibliographic information

Ecosan Club (ed.) (2011). Biogas Systems. Sustainable Sanitation Practice (SSP), Issue 9. EcoSan Club, Austria

Filter tags

Biogas systems East Asia & Pacific English Middle East & North Africa Renewable energies and climate change (WG3) Sub-Saharan Africa

Download