 The aim of the HPGR Circuits project is to characterize the performance of High-Pressure Grinding Rolls technology (HPGR) in closed circuit with either wet or dry classifiers, and to quantify the effect of recycled material for design and scale-up purposes. This is an 18 month project running in parallel with the Mineral Processing project AMIRA P9.
HPGRs are emerging as an important new comminution process in mineral processing circuits primarily because they offer substantial energy savings. There is good evidence from previous work that High Pressure Grinding Roll (HPGR) technology is more energy-efficient than the typical tumbling comminution machines including autogenous, semi-autogenous and ball mills. HPGR technology has been widely used in the cement industry and, to a lesser extent, in the diamond industry, but rarely in the wider mineral industry.
In addition, the use of HPGR technology has the potential to provide significant capacity increases in existing plants because there is evidence that HPGR product has a significantly lower Bond Work Index, and therefore will grind to the required size more quickly. Furthermore, HPGR technology may allow a simpler up-stream process compared with AG/SAG mills.
Most comminution devices operate in closed circuit with a classifier. However, there is no accepted way to achieve recycle with an HPGR in mineral comminution circuits. This seriously limits the potential energy efficiency of the HPGR. There is currently no test facility and procedure available where the performance of the HPGR in closed circuit with a classifier can be quantified and scaled up. The technical challenge in achieving effective classification of HPGR product occurs because the HPGR product is usually compressed into a flake product. There is also no procedure or equipment for characterising the effect of recycled material in the HPGR circuit. In this project a key component of the work will be the development of a HPGR flake-strength test that will enable an appropriate de-agglomeration and classification option to be quickly identified.
The major objectives of this project are to:
- Develop a laboratory test procedure to characterize the relative strength and other relevant physical characteristics of the HPGR flake to ultimately enable its ease of de-agglomeration and classification to be ranked with other materials
- Identify suitable de-agglomeration and classification options for the HPGR products tested
- Develop a lab-scale continuous HPGR circuit that includes a pilot-scale classifying device, and if required, de-agglomerators suitable for breaking HPGR flakes
- Quantify the effect of recirculating load on the performance of the HPGR
- Quantify the effect of moisture on the performance of the HPGR if used together with a wet classification stage
Contact Information
Isles Road, Indooroopilly, Qld Australia 4068
Phone:+61 7 3365 5888
Fax: +61 7 3365 5999
Email: jkmrc@uq.edu.au |
HPGR Circuits 
AMIRA