This section details the proposed processing flowsheet, historical operating data, and metallurgical testwork results for the K.Hill manganese project.
Report context
This report, dated March 2022, was prepared for Giyani Metals Corporation by SRK Consulting (KZ) Limited under project number KZ0647. Section 17 of the report presents the recovery methods proposed for the K.Hill project, drawing on historical plant data, process design criteria, and metallurgical testwork conducted by Mintek and Lab 4.
Processing route
Process Flowsheet Development
The proposed process flowsheet was developed based on metallurgical testwork and historical operating data. The flowsheet comprises crushing, grinding, acid leach, solution purification, solvent extraction, crystallisation, and product handling stages.
Crushing
Run-of-mine ore is fed to a primary crushing circuit. The design basis for the crushing stage is derived from the process design criteria established during the preliminary economic assessment (PEA) mining study.
Grinding
The crushed ore is milled in a grinding circuit to achieve the required particle size distribution for downstream leaching. The grinding circuit design parameters are consistent with the overall process design criteria.
Acid Leach
The ground ore reports to an acid leach circuit where manganese is dissolved using sulphuric acid. This stage represents the primary extraction step in the flowsheet. Metallurgical testwork by Mintek on K.Hill Main and B-Horizon samples investigated manganese variability leach extractions.
Solution Purification
Following leaching, the pregnant leach solution undergoes purification to remove impurities. This step prepares the solution for subsequent solvent extraction.
Solvent Extraction
The purified solution is processed through a solvent extraction circuit to concentrate and further purify the manganese-bearing solution prior to crystallisation.
Crystallisation
Manganese is recovered from the purified solution via crystallisation, producing a final manganese product.
Product Handling
The crystalline product is dewatered, dried, and packaged for shipment. The product handling section includes equipment for storage and loading.
Key reported parameters
| Parameter | Design Basis | Historical Operating Data | Testwork Basis |
|---|---|---|---|
| Crushing circuit configuration | From PEA process design criteria | Not reported | Not reported |
| Grinding circuit design | From PEA process design criteria | Not reported | Not reported |
| Acid leach conditions | Not reported | Not reported | Mintek variability leach extractions on K.Hill Main and B-Horizon samples |
| Solution purification steps | From PEA process design criteria | Not reported | Not reported |
| Solvent extraction stages | From PEA process design criteria | Not reported | Not reported |
| Crystallisation method | From PEA process design criteria | Not reported | Not reported |
| Metallurgical recovery | Not reported | Not reported | Lab 4 metallurgical testwork and Mintek testwork |
Technical qualifications
The report contains specific limitations regarding the recovery methods information presented. No detailed flowsheet diagrams, equipment specifications, or operating conditions beyond those listed in the process design criteria are provided. The metallurgical testwork results from Lab 4 and Mintek are referenced but not presented with full extraction data in this section. No economic parameters, capital or operating cost estimates, or project ownership details are included. The report does not specify whether the process design criteria represent final engineering or preliminary study level design.
Source: SRK Consulting (KZ) Limited, K.Hill MRE Update, March 2022, Section 17 Recovery Methods, Sections 13.4 Lab 4 Metallurgical Testwork and 13.5 Mintek Metallurgical Testwork.
