LAUSR

Abstract One of the major problems in using coal as an energy source is the high sulphur content presence. The combustion of coal releases sulphur dioxide emissions into the atmosphere which create air pollution and cause harmful effects on the ecosystem. In the current study, biodesulphurization of Waterberg steam coal was investigated using a bacterial consortium isolated from coal. Coal samples were classified into particle size fractions of +4.60 mm, −4.60 + 2.30 mm, −2.30 + 1.00 mm and −0.85 mm prior to biodesulphurization treatment. The characteristic properties of the coal samples were analysed by means of a number of techniques, including Leco S-628 Elemental analyser, UV Spectrophotometry, bomb calorimeter and X-Ray Fluorescence. Results from this study showed a reduction efficiencies of 70.3%, 51.0% and 43.8% for pyritic sulphur, organic sulphur and sulphide sulphur respectively with 18 days treatment. A maximum sulphur reduction efficiency of 65.4% was achieved, ash content reduced by some 33% and calorific value improved by 19% which suggests that desulphurized coal produce more heat than the untreated coal. Furthermore, techno – economic assessment of biodesulphurization technology was evaluated compared with other technologies that have reached full largescale application and appears to be competitive.