Loose biomass briquettes production process in Maphophe village of Limpopo province of South Africa

Deforestation has significantly affected availability of reliable low cost energy resources in low income rural households. As a result, off grid communities are becoming less and less reliant on round wood for energy. However, large amounts of agricultural and forestry residues that are produced annually are destroyed in perennial veld fires and some are deliberately destroyed to prepare for new crop fields. Accessing these loose agricultural and forest residues for energy use is one possible panacea. In the process, the challenges of deforestation can also be partly addressed. The main aim of this paper is to report on adopted methods to produce loose biomass briquettes using agricultural and forestry residues collected from the Maphophe village in Limpopo Province of South Africa. The goal was to avail workable processes for harnessing energy from loose biomass available in this locality. Production methods, energy content and combustion behaviour formed key performance variables. Two types of binders were tried, namely cow dung and cactus plant paste. A 30 tonne hydraulic press was using to compact the mixture of loose biomass and binder into briquettes. Out of 12 loose biomass samples collected, the best performing include ground nutshells, Mopani leaves, yellow thatching grass and sugarcane leaves. Performance was based on density, energy content and combustion behaviour. Cow dung was found to be the best binder and produced briquettes that offer a viable energy source for off grid communities.

1.0 Introduction

Thermal energy demand remains a major challenge in Sub-Saharan Africa. The review on Sub-Saharan African biomass national policies indicate that embracing biomass energy is a positive step in developing low carbon economic growth [1]. The most affected are rural communities with low source of income and living off the electricity supply grid. The most viable source of thermal energy for rural communities is round wood for space heating and cooking. However, this leads to deforestation which contributes to climate change.