Reduction in air pollution using the 'basa njengo magogo' method and the applicability to low-smoke fuels

Lukas J Le Roux^I; Mark Zunckel; Shirley McCormick

^IMaterials Science and Manufacturing, CSIR, Pretoria

ABSTRACT

The then Department of Minerals and Energy (DME) piloted the top-down Basa njengo Magogo alternative fire ignition method at Orange Farm during the winter of 2003. In total, 76% of households reported less smoke in their homes, while 67% reported less smoke in the streets after one month of using the method (Palmer Development Consulting, 2003). Work by Nova (Schoonraad & Swanepoel, 2003) in eMbalenhle (actual environmental tests) indicated up to a 60% reduction in smoke compared with the conventional method of bottom-up ignition. To support the findings of the environmental studies, the CSIR were appointed by the DME to conduct an experiment under controlled laboratory conditions to gather quantitative data on the reduction in particulate emissions associated with the Basa njengo Magogo method of lighting coal fires. The CSIR was further contracted to assess whether the Basa njengo Magogo technology was viable with low-smoke fuels.
The experiment was conducted using traditional D-Grade coal in both the conventional bottom-up and the Basa njengo Magogo ignition techniques. Three low volatile fuels were also assessed using the Basa njengo Magogo method namely:
• Anthracite (volatile content of 10.6%)
• Anthracite (volatile content of 12%)
• Low volatile coal (volatile content of 20.8%), from Slater Coal in Dundee.
All four fuels using the Basa njengo Magogo method recorded similar times of between 11 and 13 minutes from ignition to the fires reaching cooking temperature. The bottom-up fire for conventional D-Grade coal reached cooking temperature after 55 minutes.Particulate emissions from all the Basa njengo Magogo fires were similar and up to 92% lower in particulate emissions than that of the D-Grade coal in the bottom-up fire. SO₂ emissions from the two D-Grade coal fires were the lowest and were identical. The highest SO₂ emission resulted from the low volatile coal. The method of lighting the fire does not have a significant effect on the SO₂ emissions. The Basa njengo Magogo method of ignition uses approximately 1 kg less coal to reach cooking temperature than the traditional bottom-up method. At a cost of approximately R1.00 per kilogram of coal, this translates into a cost savings of approximately R30 per month.

Keywords: air pollution, Basa njengo Magogo, low-smoke fuels, cooking temperature

Full text available only in PDF format.

Acknowledgements

• The DME for sponsoring the project.
• Mrs Mmathabo Murubata of Palmer Development Consulting for training.
• Eddie Erasmus, Vongani Nkhwashu, Alphius Bokaba and Rietha • Oosthuizen of the CSIR for technical support.
• Slater Coal and Afriore for the supply of coal samples.

References

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Le Roux, L. J., Cilliers, K. F P and Van Vuuren, D. S., 2004. Low-Smoke fuels Standard Testing and Verification. Final Report to the Department of Minerals and Energy. CSIR Report No. 86DC / HT776.         [ Links ]

Le Roux, L. J., Zunckel, M. and McCormick, S.G., 2005. Laboratory Controlled Quantitative Information about Reduction in Air Pollution using the 'Basa njengo Magogo' methodology and Applicability to Low-Smoke Fuels. CSIR Report No. ENV-D-C 2005-004.         [ Links ]

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Received 23 January 2009
Revised 18 June 2009