Kinetic Study of the Oxidation and Fusion of Copper Concentrate Particles in a Gas Stream.

本工作旨在测定铜精矿颗粒在较低温度下不发生着火时的氧化速率，为分析铜闪速熔炼炉内的反应提供基础知识。当转化率小于0.2时，氧化受控于化学步骤，而当转化率大于0.2时，氧化受控于形成的氧化层中的气体扩散。根据实验观察，确定了动力学参数。另一方面，还研究了铜精矿颗粒落入垂直管内的氧化和熔融过程。建立了包括氧化动力学、颗粒间、气流与垂直反应管之间的传热传质的数学模型。通过实验观察和基于数学模型的计算发现，在点火温度和氧气充足的情况下，精矿颗粒由于快速氧化而被反应热熔化。浓缩物粒子的融合发生在大约0.4秒的很短的时间内。

It was intended in this work to measure the oxidation rate of copper concentrate particles at rather lower temperature at which the ignition of particles did not occur, in order to get fundamental knowledge for the analysis of reactions in copper flash smelting furnace. When the conversion was less than 0.2, theoxidation was controlled by chemical step, while it was controlled by gas diffusion through the formed oxide layer when the conversion was higher than 0.2.Kinetic parameters were determined based on the experimental observations.On the other hand, the oxidation and fusion of copper concentrate particles falling in a vertical tube were also studied. A mathematical model was developed in which the oxidation kinetics, and heat and mass transfer between particles, gas stream and vertical reaction tube were included. It was found from the experimental observations and computation based on the mathematical model that the concentrate particles were melted by the heat of reaction due to a very rapid oxidation provided that the particles attained at an ignition temperature and enough amount of oxygen was available. The fusion of concentrate particles took place in a very short time of about 0.4 seconds.