Grinding Circuits Problem 1 A two stage grinding circuit using a rod mill in open circuit and ball mill in closed circuit with a hydrocyclone classifier is used to grind 100 tons/hr of ore (sp. gr. 3.0). Overflow Hydrocyclone Water Feed Rod mill Ball mill Sump Pump Underflow The circuit is sampled and analysed for -200 mesh material and percent solids. % solids Results of tests for samples % -200 mesh Rod mill discharge 5 Ball mill discharge 20 Cyclone overflow 30 Cyclone underflow 15 75.18 78.33 40.00 80.00 (1) Carryout a material balance and calculate the tons/hr of dilution water added to the sump (ii) Calculate the flowrates of slurry, solids and water of all streams and specific gravities of all streams and illustrate the material balance of the whole circuit