This report describes the proposed mineral processing route for the Mphahlele PGM Project, including metallurgical testwork and design criteria for a plant treating Merensky and UG2 Reef material.
Report context
The Mphahlele PGM Project is located in Limpopo Province, South Africa. This technical report was prepared for Sedibelo Platinum Mines Ltd with an effective date of 31 December 2021 and a report date of 27 May 2022. The mineral processing and metallurgical testing section (Section 13) and the recovery methods section (Section 17) form the basis of this processing overview.
Processing route
Nature of metallurgical testing and analytical procedures
Metallurgical testing included radiometric sorting (Rados) test work, milling and flotation test work, and test work interpretation and plant circuit selection. The testing program was designed to support the proposed flowsheet for the project.
Radiometric Sorting (Rados) Test Work
Radiometric sorting test work was conducted as part of the metallurgical test program. Design criteria for the Rados system are included in the plant design specifications.
Milling and Flotation Test Work
Milling and flotation test work was performed to develop the process flowsheet. The test work informed the design of primary and secondary milling stages, as well as primary and secondary rougher and cleaner flotation circuits.
Test work Interpretation and Plant Circuit Selection
The test work was interpreted to select the proposed plant circuit. The proposed flowsheet includes run-of-mine (RoM) ore handling, secondary crushing, primary milling, primary rougher flotation, secondary milling, secondary rougher flotation, primary cleaner flotation, secondary cleaner flotation, concentrate dewatering, concentrate filtration, tailings dewatering and disposal, water distribution, reagent addition, and metal accounting and sampling.
Proposed Design Parameters
The plant throughput and design specifications include general RoM characteristics, Rados design criteria, crushing (primary) specifications, primary milling parameters, primary rougher flotation design, primary cleaner flotation design, secondary milling specifications, secondary rougher flotation design, secondary cleaner flotation design, concentrate thickening and dispatch systems, tailings disposal arrangements, and reagent addition systems.
Requirements for energy, water, consumables and personnel
The report includes requirements for energy, water, consumables and personnel for the proposed processing plant. These are design basis parameters for the proposed operation.
Plant recovery and deleterious factors/elements
Deleterious factors and elements were considered in the test work and plant design. The report addresses plant recovery and the management of deleterious elements in the process design.
Representivity of test samples
The representivity of test samples was assessed as part of the metallurgical testing program. Sample representivity is a factor in the adequacy of the data for plant design.
Testing laboratory and certification
The testing laboratory used for the metallurgical work is identified in the report, along with relevant certification information.
Key reported parameters
| Parameter | Units | Design/Proposed | Historical/Actual | Testwork Basis |
|---|---|---|---|---|
| Plant throughput | Not specified | Design criteria provided | Not reported | Testwork data used |
| Crushing | Specification | Primary and secondary | Not reported | Testwork informed |
| Primary milling | Specification | Design criteria | Not reported | Testwork data |
| Primary rougher flotation | Specification | Design criteria | Not reported | Testwork data |
| Primary cleaner flotation | Specification | Design criteria | Not reported | Testwork data |
| Secondary milling | Specification | Design criteria | Not reported | Testwork data |
| Secondary rougher flotation | Specification | Design criteria | Not reported | Testwork data |
| Secondary cleaner flotation | Specification | Design criteria | Not reported | Testwork data |
| Concentrate dewatering | Specification | Design criteria | Not reported | Not specified |
| Concentrate filtration | Specification | Design criteria | Not reported | Not specified |
| Tailings disposal | Specification | Design criteria | Not reported | Not specified |
| Reagents | Specification | Design criteria | Not reported | Not specified |
Note: The report does not provide specific numerical values for throughput, recoveries, grades, or other performance metrics in the processing sections reviewed. All parameters are presented as design criteria without actual or historical operating data for this project.
Technical qualifications
The report includes several important limitations. No historical operating data is available for this project as it is a proposed development. The plant recovery and deleterious factors/elements are addressed only in the context of testwork and design criteria. The adequacy of data for plant design is stated to be based on the metallurgical testwork program. Non-commercial process or plant design is noted in the report. The report does not provide actual plant performance data, and all processing parameters are design basis values derived from testwork and interpretation.
