低钒转炉钢渣提钒湿法工艺的动力学研究

Vanadium Recovery from BOF Slag Containing Low-Vanadium Oxide

摘要:

为了提高湿法浸出低钒钢渣中钒的浸出效率，并对湿法浸出低钒钢渣中钒提供理论依据，从动力学角度分析整个浸出过程。考察温度、液固比、硫酸质量分数和搅拌速率对浸出过程的影响。研究结果表明：在90 ℃、液固比为10?1以及硫酸浓度6.0 mol/L时，浸取9 h，低钒钢渣中钒的浸出率可达到95.3%。通过正交实验和动力学推导，得到描述浸出过程的经验方程，低钒钢渣湿法浸出钒的动力学模型为收缩核动力学模型，浸出过程的表观活化能为12.794 kJ/mol，该模型表明浸出过程中的控制步骤取决于固膜扩散速率。提高温度、液固比和硫酸质量分数，均可加速钒的浸出速度，提高钒的浸出率

Abstract:

In order to improve the leaching efficiency of vanadium pentoxide from BOF slag containing low-vanadium oxide and provide theoretical foundations, the whole leaching process was analyzed from the kinetic aspect. The effects of reaction temperature, the liquid-solid ratio, sulphuric acid concentration and stirring speed on the leaching efficiency were investigated. The results show that the leaching rate of vanadium pentoxide can reach 95.3% under the condition of temperature 90 oC, liquid-solid ratio 10: 1, sulfuric acid concentration 6 mol/L, and leaching time 9 h. By means of the orthogonal experiment and kinetic deduction, an empirical equation for the leaching process is established, and the apparent activation energy is 12.794 kJ/mol. The leaching process of BOF slag containing low-vanadium oxide could be simulated with a shrinking core model, which indicates that the control factor of the leaching process is the diffusion rate of reacting reagents in a porous solid layer. The leaching efficiency and speed can be increased by enhancing the temperature, liquid-solid ratio and sulfuric acid concentration