高级检索

碳质金矿与氰化尾渣协同焙烧的动力学研究

Kinetic study on synergistic roasting of carbonaceous gold ore with cyanide tailings

  • 摘要: 针对某低品位碳质金矿常规氰化回收率低的问题,开展了碳质金矿与氰化尾渣协同焙烧的非等温动力学研究。在惰性N2气氛下,采用热重分析法(TG-DTG)对混合样品进行多升温速率(5 K/min、10 K/min、15 K/min、20 K/min)的热解分析。通过结合无机理模型(Flynn-Wall-Ozawa与Kissinger-Akahira-Sunose)与机理模型(Coats-Redfern)进行动力学参数计算与模型识别,结果表明,协同焙烧过程可分为3个阶段,其核心质量损失阶段(转化率15 %~70 %)符合随机成核与生长机制,最概然动力学模型为Avrami-Erofeev函数,平均活化能为253.93 kJ/mol。该研究为协同焙烧工艺的温度与时间等关键参数优化提供了理论依据。

     

    Abstract: A non-isothermal kinetic study was conducted on the synergistic roasting of a low-grade carbonaceous gold ore from Shaanxi Province and cyanide tailings, aiming to overcome the low gold recovery inherent to conventional cyanidation. Thermogravimetric analysis (TG-DTG) was conducted on mixed samples under an inert N2 atmosphere at heating rates of 5 K/min、10 K/min、15 K/min, and 20 K/min. Kinetic parameters were determined, and the reaction model was identified by integrating model-free methods (Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose) with the model-fitting Coats-Redfern. The results show that the synergistic roasting process can be divided into three stages. The main weight-loss stage (conversion \alpha = 15 %−70 %) conforms to the random nucleation and growth mechanism. The most probable kinetic model is the Avrami-Erofeev function, with an average apparent activation energy of 253.93 kJ/mol. This study provides a theoretical basis for optimizing key parameters such as temperature and time in the synergistic roasting process.

     

/

返回文章
返回