Fundamental comminution efficiency gains with the CAHM platform technology

The Conjugate Anvil Hammer Mill (CAHM) is a platform technology invented by Lawrence Nordell that embodies Dr Klaus Schönert's guiding principles for highly efficient comminution into a series of commercial, production-scalable devices across multiple product size ranges. Schönert demonstrated that unconfined, compression breakage of single particles (or thin particle beds) between parallel plates produces the most energy efficient particle breakage. The CAHM Mark 1 Prototype and the MonoRoll are 2 new comminution devices that leverage these fundamental principles to produce comparable breakage at a fraction of the energy consumed by SAG mills, Ball mills or even High Pressure Grinding Rolls. The CAHM machine prototype has been tested at feed rates in excess of 60 t/h and is robust enough to be operated at a mine site for a pre-commercial demonstration. The MonoRoll is a 2 t/h retrofit of an existing pilot-scale ball mill. A mining industry consortium led by the Canada Mining Innovation Council and supported by Quebec and Federal government funding has designed, fabricated and tested both prototype machines over the last 4 years. Beyond the dramatic energy savings, implementing these technologies will generate additional benefits from simpler circuits and reduced scope 1, 2 and 3 carbon emissions. This paper reviews the design of these 2 prototypes in the context of Schönert's fundamental principles for efficient breakage.