Ann: Successful Boiler Trial Using Sese Coal , page-2

African Energy Resources demonstrates Sese coal’s suitability for industrial boilers in trial

Wednesday, August 22, 2012 by Angela Kean


African Energy Resources (ASX: AFR) has successfully demonstrated the suitability of coal from its Sese Thermal Coal Project in Botswana to be used as fuel for industrial boilers in a recently completed trial.

A 15,000 tonne bulk sample was excavated from part of the Measured Resource earlier this year and has provided coal for beneficiation test work, export trials and combustion testing.

Sixty tonnes of raw coal from the bulk sample was recently trucked to South Africa where it was crushed and processed through Gecko Mineral Processing’s pilot-scale air-separation plant to provide information on air plant performance and a beneficiated product for combustion testing in boilers.

The processed coal was screened to “peas”, a 6 by 25 millimetre sized product, and three random samples sent to ALS Chemex Witlab facility for coal quality analysis.

Bagged samples of the sized coal were sent to GH Boiler and Energy Services in Johannesburg for the combustion trial.

Sized Sese coal was fed onto the boiler’s chain-grate by means of an overhead hopper, and introduced to the boiler as a replacement for the boiler’s standard 25.5 megajoules per kilogram feedstock.

The following key observations were made:

- Sese coal was observed via a peephole and was seen to ignite and combust well.

- The process and efficiency was monitored throughout the trial and indicated that Sese coal combusted favourably and successfully with no adverse impact on the boiler.

- The boiler was able to generate heat and steam satisfactorily using Sese coal.

- Stack emissions were noted and recorded as clear throughout the test.

- Soft and friable clinker was seen at the back-end of the chain-grate and was not detrimental to the boiler performance or ash recovery.

Importantly, all of these observations confirm that Sese coal is therefore compatible with and suitable for use in industrial chain-grate boilers.