:: Young African Engineer Applies JKMRC Know-how in Tanzania

The JKMRC has an enviable record of attracting some of the brightest young engineers from equatorial Africa to engage in postgraduate research through the University of Queensland in Australia. Making significant progress towards the completion of a Masters degree with the JKMRC is Raymond Ackabah, a Senior Processing Engineer with Geita Gold Mine in Tanzania. The Geita Gold Mine is a joint venture between Ashanti Goldfields and Anglogold and is the largest mine in Tanzania. In 2003 it produced over 660,000 ounces of gold. The Geita Gold processing plant was originally designed to process 500 tonnes of ore an hour, and through optimisation has increased to 600 tonnes an hour.

Originally from Ghana, Ray's main research interest through the JKMRC is to analyse the performance of the secondary crushing circuit he was involved with retro-fitting at the Geita Gold processing plant at the end of 2002. "Now that we have retrofitted a secondary crushing circuit we are looking at processing about 700 tonnes an hour,"Ray said. "The addition of the secondary crushing circuit was motivated by the ore's hardness and an increase in the ore reserve base."

Ray will be looking at the effect of operating the SAG mill at different load levels. He said Geita Gold hopes to increase the ore treatment rate to six million tonnes per annum.

Ray Ackabah first came into contact with the JKMRC in 1998 during the Geita Gold mine project feasibility study stage when he sought guidance through the JKMRC's pioneering text "Mineral Comminution Circuits -Their Operation and Optimisation" which was edited by Napier-Munn, Morrell, Morrison and Kojovic.

Ray said the material contained in the book was world-class. In May 1999 he had an opportunity to attend an introductory course in JKSimMet which was facilitated by JKMRC Technical Director Dr Rob Morrison. JKTech's Dr Glen Corder introduced Ray to particular applications of process control. In 2000 Ray organised a circuit survey at the Geita Gold operation to help train local staff. JKTech Principal Consultant Chris Bailey visited the site to train operators in sampling and JKSimMet. In 2001 Ray attended Anglogold's milling school in South Africa, facilitated by Dr Steve Morrell.

He ultimately hopes to derive a power model specific to the Geita milling circuit, construct mathematical models of the performance of the SAG mill when operated at different feed sizes and load levels, and then determine optimum operating conditions. Ray Ackabah expects to complete his Masters degree in 2005.