### Investigation into the applicability of Bond Work Index (BWI) and ...

Oct 15, 2015 ... Bond Work Index (BWI) & Hardgrove Grindability Index (HGI) tests for biomass & coal. ... [7,8], and the Bond Work Index (BWI) for tube and ball mills [9,10]. ..... what is required for combustion in pulverised fuel coal burners [46].