Pyrometallurgy: Roasting, Smelting, Refining & Electrowinning

Normally, the calcine product from fuildized bed roaster overflow ,WHB dust go to the cooling drum cum ball mill , if you have find any coarser in content , may  treat classifier  cum we ball mill in NL underflow thickner , may avoid the coarse fraction improve the recovery

Okay, got it. But what kind of ball mill you could recommend? we have three roasters, when two roaster work it somehow can handle it. But in case of 3 roasters ball mill has problem. Capcaity is 10 t/h but I guess, actually it less. 

Hello

i just joined and saw this old thread.

zinc roaster calcine is ground in dry or wet ball mills. The most common practice involves cooling the calcine with a rotary water-tube cooler or a fluidized bed water tube cooler. For dry grinding the Cooled calcine is fed to an air-swept rotary ball mill. Almost all installations use open-circuit mills with air circulating through a cyclone to collect the ground solids. Bleed air exits through a bag house. Hardened steel balls are the typical grinding media. 

At some smelters calcine is cooled and then stored before wet grinding. Closed-circuit ball mills thus become the first step of the leaching circuit. Grinding occurs with the leaching solution and the mills are rubber lined because of the acidity of the solution.

in most roaster circuits dry grinding is done only on the bed overflow calcine and waste heat boiler calcine. Fine solids from gas cyclones and electro static precipitators usually bypasses the air-swept ball mill. Wet mills grind the combination of all calcine.