Case study of dry HPGR grinding and classification in ore processing.

Dry high-pressure grinding roll (HPGR) processing is gathering interest from industries that are operating in areas where water scarcity or process conditions require a minimising of water addition and energy consumption. HPGR technology could provide solutions even in operations where a very fine grind is required, by applying closed circuit arrangements with air classification, especially in the case where an integrated arrangement is used such as with the COMFLEX plant. Building on available processes and experiences from cement processing, tailored products can be generated at high throughput rates. This publication summarises some of the features and experiences with dry HPGR processing. Descriptive iron ore case studies are presented illustrating the process steps and grinding equipment arrangement to provide for fine products in a range of 20-125 micrometers from a feed size of 50 mm.
Dry high-pressure grinding roll (HPGR) processing is gathering interest from industries that are operating in areas where water scarcity or process conditions require a minimising of water addition and energy consumption. HPGR technology could provide solutions even in operations where a very fine grind is required, by applying closed circuit arrangements with air classification, especially in the case where an integrated arrangement is used such as with the COMFLEX plant. Building on available processes and experiences from cement processing, tailored products can be generated at high throughput rates. This publication summarises some of the features and experiences with dry HPGR processing. Descriptive iron ore case studies are presented illustrating the process steps and grinding equipment arrangement to provide for fine products in a range of 20-125 micrometers from a feed size of 50 mm.