6 200 25 2 4 very weak4 2 stage before dryer kbf sub 4 0 6 450 30 4 6 weak5 2 stage before dryer libf sub 4 0 6 200 25 3 6 weak6 2 stage before dryer ca bf sub 4 sub 2 0 6 200 18 4 8 weak7 2 stage before dryer nabf sub 4 0 05 400 u2266 15 3 8 indicated8 2 stage before dryer kbf sub 4 0 05 450 u2266 15 3 6 indicated9 2 stage after dryer nabf sub 4 0 3 400 35 3 6 weak10 2 stage after dryer kbf sub 4 0 3 450 35 4 6 weak11 2 stage after dryer nabf sub 4 0 3 400 60 4 6 very weak__________________________________________________________________________ the dryer temperature was adjusted for each specific mineralizer to avoid possible decomposition the temperature gradient of the rotary oven was in contrast the same for all examples at the inlet 750 u00b0 c at the outlet 1350 u00b0 c in all the examples 1 11 the same aluminum hydroxide produced according to the bayer process was used it had a mean agglomerate size of lt 60 u03bc and contained 0 4 wt na 2 o.