The flow properties of a coal slurry suspension are highly dependent on the properties of the coal, particles suspended within the fluid, volume concentration and addition of chemical additives. Rheological studies focus on measuring these fluid properties using rheometers. Therefore, investigating and improving these properties in slurries helps in producing a highly concentrated suspension with good stability and low viscosity.
South Africa has large low-grade coal reserves and with the prospect of expanding coal demands for exports and power generation, it is important that the beneficiation and transport of coal in the country be economical. The current means of transporting coal by trucks and trains faces serious problems including inefficient rail infrastructure, long distances and several environmental concerns related to air pollution and water pollution and traffic hazards. It is therefore important to investigate an efficient means of coal transportation with environmental benefits. It is possible to achieve this efficiency through the transportation of coal as slurry through pipelines.
In this research, coal-water mixtures (CWMs) prepared from two different South African coals from Waterberg and Witbank coals areas will be investigated to optimize the parameters of a CWM having an ideal behaviour of a maximum coal loading, high stability and low viscosity. For this purpose, the effect of the parameters such as the amount and dosage of chemical agents, particle size distribution and coal concentration will be investigated. The aim of this research is to prepare coal-water slurries with a high concentration of coal, low viscosity and a good stability.
Gyebi, P. and Franzidis, J-P. 2014. Technical feasibility of South African coal water mixtures (CWMs). Poster presented at the at the 32nd annual SAIMM Mineral Processing Conference, 7-8 August, Cape Town.