The heavy mineral sand mining operation north of Richards Bay, Richards Bay Minerals (RBM), has approved over R1-billion in funding for its tailing treatment plant project (TTP).

Improved knowledge on mineralogy and ore body attributes, supported by intensive test work, has resulted in this approval by the RBM board of directors.

The mineral separation process at RBM, over the past 32-years of its operations, resulted in some valuable minerals being discarded with the tailings, which were stockpiled. In-house research and development has now identified the technology to separate these valuable minerals from the currently mined and stockpiled tailings. To achieve this, a new TTP plant will be built at the smelter site, with a smaller operation in the mining area.

RBM GM Dawid Erasmus says the purpose of the TTP is to recover the valuable minerals rutile, zircon and ilmenite from tailings, to produce concentrates that will supplement mineral seperation plant (MSP) rutile and zircon plant feeds, and produce ilmenite concentrate.

"Throughout RBM operations, MSP tailings have been back-hauled to the mine and stockpiled in suitable repositories, referred to collectively as stockpile tailings. With the commissioning of the TTP the stockpile tailings will be transported for processing in the TTP," Erasmus explains.

He adds that going forward, all tailings arising from the MSP operation would also be processed through the TTP. "These current tailings will be treated preferentially to the stockpile tailings, with the stockpile tailings making up the plant capacity," he says.

RBM's MD Cameron McRae says the TTP project is the first big expansion since the mine upgrade project 2000 (MUP), between 1996 and 2000. The construction duration for the TTP is 2008 to 2010, and it will extend the life of mine by another five years when it comes into production in July 2010.

McRae adds that the project is an excellent business case. "It will contribute to the economics of the greater KwaZulu-Natal by providing further employment and local business development opportunities during the construction period, as well as into the future. The additional value created in RBM through this project will also benefit the new shareholders, communities and employees, with increased equity flows following the completion of the broad based black economic-empowerment deal, currently being finalised."

He adds that given the current power crisis in South Africa, the TTP will act as a significant insurance to continued revenue generation through the efficient production of zircon, rutile and ilminite feedstock at low cost/MW usage. What this means is when compared to the existing dredge mining process, the new TTP will consume less electricity to generate the same tons of production.

To further mitigate the electricity shortage, RBM plans to generate sufficient electricity in-house to be able to supply the TTP's requirements, which is 6,5 MW by 2010. McRae states that a target of 35 MW electricity through self-generation by 2011 is achievable. He adds that this is still work in progress and will be implemented in phases over the period 2008 to 2011.

Self-generation will be achieved by fuelling 20 gas engines with the excess furnace gas available to generate electricity. This creates exiting opportunities for further efficiency improvements by using the exhaust gas for further drying, or heating.

RBM is a leading mineral sands producer, situated north of Richards Bay in Zululand, KwaZulu-Natal. Shareholding in the company is split equally between two of the world's largest diversified mining companies BHP Billiton and Rio Tinto. RBM's core business is extracting heavy minerals from the dune sands, with beneficiation to produce rutile, zircon, titania slag and high purity pig iron.

The company employs over 1 700 permanent staff and around 1 500 contractors at any one time.

To subscribe to Mining Weekly's print magazine email subscriptions@creamermedia.co.za or buy now.