This study investigated the commissioning and maintenance of a Pennells two-tank
bioreactor system with specific reference to its application in rural areas of KwaZulu-
Natal, South Africa to treat sewage and generate biogas. The septic tank configuration was
installed in a community which lacked electricity and domestic waste disposal. An artificial
wetland was constructed at the outlet of the system to facilitate further treatment.
Inefficient operation and maintenance of the system occurred due to various
social/community-related problems which are typical of a field- and community-based
project of this nature in a rural region of a Third World African country. These problems
affected both maintenance and digester performance. The Pennells system was
characterized by incomplete anaerobiosis which limited methanogenesis. Despite this, and
attendant problems of low temperatures and elevated pH values, COD removal resulted.
Laboratory-scale batch cultures, in conjunction with fluorescence and scanning electron
microscopy, were used to identify a suitable anaerobic digester sludge for inoculation
purposes. Perturbation experiments with locally used detergents and toxic compounds
demonstrated the inimical effects of these agents. In contrast, low concentrations of
penicillin and tetracycline promoted methanogenesis. Further analysis with light,
fluorescence and scanning electron microscopy identified the acidogens as the predominant
bacterial species, whilst fluorescence microscopy confirmed the absence of methanogens
in the bioreactor. / Thesis (M.Sc)-University of Natal, Pietermaritzburg, 1997.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ukzn/oai:http://researchspace.ukzn.ac.za:10413/5420 |
| Date | January 1997 |
| Creators | Taylor, Michelle Anne. |
| Contributors | Senior, Eric. |
| Source Sets | South African National ETD Portal |
| Detected Language | English |
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