Industrial Application of Large Rotary Kiln for Recovery of Vanadium from Vanadium Slag Added MnVO_4 in Calcium Roasting Process

摘要

Calcification roasting was an effective and environment-friendly way to extract vanadium from vanadium slag. This paper presents a comprehensive study on industrial application of calcium roasting process for large rotary kiln. The study has highlighted the importance of temperature stability using MnVO_4 for maximizing the recovery of the vanadium. The optimum conditions for recover 87.48-89.65% of vanadium (V) by using MnVO_4 at M-Fe concentration 1 ±0.5%, CaO to V_2O_5 ratio 0.58-0.64, MnVO_4 concentration 50-55%, feed rate 4.44±0.56 kg/s, rotate speed 87-90 s/r, temperature of T2 865±10℃, temperature control curves TE, TF, TG, negative pressure -10±5 Pa and volume flow ratio of the combustion air to coke oven gas (5-5.5). It was possible MnVO_4 was not only the additive but also play a key auxiliary effect for CaO with vanadium (V) to Ca_2V_2O_7 by studying on the oxidation reaction mechanism.