Case Study of Dry HPGR Grinding and Classification in Ore Processing

The number of projects dealing with or considering dry processing increases due to factors such as:

- Low water availability in arid locations, such as the high Andes or Sahara desert

- Dry downstream processing or beneficiation with high fines requirement.

Dry processing can provide an alternative to cope with:

- Low water availability, high supply cost, desalination requirements, drinking water preservation

- High effort and cost in fine wet product screening, sedimentation, and filtration

- Difficulties from high water content in HPGR recycle where wet screening is applied

Dry processing with HPGR and air classification is expected to become more prominent in the near future, due to water availability issues in arid areas and downstream dry processing options. Roll wear from dry ore processing can effectively be minimized by applying a RollSpray® coating arrangement. Dry processing can provide a suitable treatment option for various operations in ore processing, at low energy and cost savings as compared to other grinding techniques. Dry processing provides a technically feasible technology that can be applied in fields of minerals processing, generating beneficiation feeds at P80 sizes down from 1500 ìm to 40 ìm. Dry processing involves well established industry standard technology, with processes and equipment readily available based on cement operations.