Wet Bond mill test

The Bond grindability test is currently used in the minerals industry to provide data fundamental to the design of commercial milling installations. In some instances it was found that the work index for the fine limiting sizes (such as 53 mum) was abnormally high. Observations of the test procedure suggested that the dry screening procedure seemed likely to give rise to errors. Other alternative modified Bond test procedures were discussed to solve this problem. Wet Bond milling and screening rests were carried out to avoid incomplete screening of the circulating load at fine sizes. Because the work index required for dry milling was greater than for wet milling, in order to calculate the standard Bond index, the Bond index obtained from wet milling had to be multiplied by 1.3. The results from the dry and wet tests correlated very well.