In the first stages of the program extensive work on raw material appraisal and sample preparation and characterisation was carried out in collaboration with the Institute of Geology and Mineral Exploration (IGME). Detailed chemical and mineralogical analyses revealed main constituents and beneficiation properties. These data were used by Control International SA (CI) to develop anew ore model to be used for process simulation. Process testing performed by GM and IGME comprised a large number of laboratory, pilot and industrial scale tests with various beneficiation techniques. Furthermore GM developed, commissioned and tested a new prototype optical Sorter for the +6mm material. Based on testwork results the partners selected a generic flowsheet employing pre-separation of fines in dry state using magnetic or non-magnetic drums, followed by scrubbing and wet sieving for the preparation of the material, TRIFLO heavy media separation and then optical sorting for the +6mm fraction and magnetic separation for the 2-6mm fraction. Relevant unit operations models were developed by CI and were calibrated using the experimental data from process testing. The USIM PAC process simulator was used for the optimisation of the selected flowsheet by evaluating a great number of alternative configurations. Finally, tentative applications and market data for magnesite grades derived from the selected flowsheet were investigated.
The proposed research aims at developing new process routes for the effective bonification of waste run-of-mine fines, with an initial application in magnesite. This new process amplifies the use of novel types of photometric sorter and magnetic separator,the column flotation technique and modern simulation methods for process optimization. The production of magnesite with more than 80% MgO equivalent, at an optimal recovery,is expected after bonification according to new process. It is anticipated that subsequent exploitation of the experimental results will lead to the commercial application of novel type of equipment and the incorporation of the new procedure in the bonification plant.
The major research tasks are:
1. development of Reticon Camera Sorter (R.C.S.) for effective sorting of industrial minerals in the size range 5mm-12mm.
2. Development of new Cryogenic High Gradient -High Intensity Magnetic Separator (CHIGS) for effective removal of feebly paramagnetic material.
3. Investigation of process efficiency,comprising: Sorting by R.C.S. -Magnetic Separation by CHIGS and conventional magnets-Gravimetric Separation- Cell flotation and Column flotation.
4. Modelling of the novel types of equipment and process optimization with modern simulation methods.
Successful completion would increase the overall magnesite recovery by 60% with corresponding reduction in overall cost and waste disposal area requirements.
Funding SchemeCSC - Cost-sharing contracts
W3 7QS London