JUICE FLOW IN MILL GROOVES

摘要

Circumferential grooves are used on all rolls of crushing mills. The grooves are intended to provide a better grip on the cane or bagasse and better drainage for the large volumes of juice expressed. The second purpose has received little technical attention. Crushing investigations that attempt to model the process using advanced computational methods might need to account for these juice flows. A simple model of the flow of expressed juice through the grooves has been used to investigate the likely flow rates and pressures involved and their contribution to reabsorption.The model suggests that the pressures required even for large, high capacity mills are quite small. However, the estimated flow towards the delivery side of a roll pair makes a significant contribution to the reabsorption. Different groove dimensions do not seem to make much difference to the flow to the delivery side when the excess of bagasse volume over escribed volume is used for comparison. Juice grooves or other drainage aids are probably unnecessary and the pressures calculated are too low to inhibit mill feeding. Groove flow contributions to reabsorption will need to be accounted for in computational models that attempt to predict extraction performance.