Abstract
M.Phil.
The study was undertaken at Bosjesspruit, one of the Sasol Collieries, to
investigate aspects that contribute to the degradation of coal. Bosjesspruit is
penalised with more than nine million rands per year for fine coal that
exceeds the set limits. Compliance to quality is the main reason. The cost is
directly deducted from the profit. The quality of coal is of importance for the
effectiveness of the gasifying process.
A feasibility study has indicated that this study is viable. Various factors in
the process were studied to identify the system deviations such as: coal
bunkers, section and main conveyor belts, geology, production section
activities and coal production equipment.
A literature study was done and time was spent to become conversant with
the coal transport system. The process is described from where the coal is
mined, through the handling action up to where it is fed into the Sasol plant
gasifiers. Several coal samples of the identified bottleneck areas were taken
and analysed. The four main areas that were studied are:
Loading actions at East 700 bunker.
Incline shaft transfer chute.
The horizontal bunker on surface.
The South section conveyor chutes. The free-flow technology was researched and developed for an acceptable
chute design. The design is now computerised and in use at Sasol Collieries.
The current design and its restrictions are compared with the proposed
designs to indicate the improvements.
A detailed cost analysis was done to determine the expenditures such as:
Penalties for fine coal.
The cost of adaptability and redesign.
- Forecast cost savings after the redesigns are implemented.
- Cost to produce coal as well as the income for Bosjesspruit. An economical evaluation indicates that all the suggested solutions are
economically justifiable. The results of the study indicate several suggested
solutions to overcome the identified bottlenecks.
It is further suggested that results of this study are also implemented at the
other Sasol mines as well as the mines that are being developed.