ロータリキルンによるラテライトのソーダ焙焼について

抄録

The authos have studied on the sodium roasting and the water leaching for the separation of chromium and alminium from lateritic iron ores.
Basic roasting conditions for chromium removal were obtaind by preliminary experiment, and this result was applied to the rotary kiln and leaching equipment of laboratory scale.
The results obtained were as follows:
(1) The rotary kiln was the proper furnace for this object. High chromium and alminium separation rates were obtained under the roasting temperature of 1, 000-1, 050°C, the atmosphere of 10% O₂ and the mixing ratio of 15-20% Na₂CO₃.
(2) The addition of CaO was undesirable for the roasting of lateritic iron ores, by reason of the Na contents in leached ore was increased, and the ring of burden was grown at the high temperature zone in the kiln.
(3) Removal of Na in leached ore and establishment of economical operation are the remainded problem and must be solved hereafter.