生物堆浸过程温度分布的影响
(1. 北京科技大学 冶金与生态工程学院,北京 100083;
2. 北京科技大学 土木与环境工程学院,北京 100083;
3. 中南大学 资源加工与生物工程学院,长沙 410083)
摘 要: 在假定辉铜矿、黄铁矿生物氧化反应步骤和反应产热一定的情况下,基于反应热的计算及热力学基本理论,建立生物堆浸过程热平衡方程,研究堆浸过程反应产热、喷淋液流速率和充气气流速率对堆中温度变化及分布的影响。仿真结果显示;堆中温度的分布及变化与喷淋液流速率(Gl)、气流速率(Ga)直接相关,且与Ga/Gl有密切关系;若喷淋液流速率Gl过大,堆中热量积聚于堆的底部;若气流速度过大,则热量通过对流上升到堆的顶部;若两种流速过大均会使热量通过底部和顶部的蒸发而损失,确定合理的Ga/Gl是实现堆中温度理想分布的途径;当Ga/Gl为2/3时,堆中温度分布较好。
关键字: 次生硫化铜矿;生物浸出;生物堆浸;热平衡;温度场
of secondary copper sulfide during bio-heap leaching process
(1. School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing 100083, China;
2. School of Civil and Environment, University of Science and Technology, Beijing 100083, China;
3. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China)
Abstract:By assuming that the step and heat of the bio-oxidation reaction of chalcocite and pyrite are definite, based on the calculation of the heat of reaction, the heat balance equation of the bio-heap leaching process was established. The effects of the heat produced, the irrigation rate and air flow rate on the temperature variation and distribution were investigated. The simulation results show that the heat distribution and variation in the heap are determined by the irrigation rate and air flow rate, especially of their ratio value. When the irrigation rate over increases, the major heat would be brought to and accumulated at the bottom of the heap, conversely if the air flow rate over increases, the major heat would be accumulated at the top of the heap, both of the overlarge rate will cause heat loss from bottom or top of the heap. The determined reasonable ratio of the air flow rate to irrigation rate is an effective way to implement the ideal heat distribution in the heap. The optimized Ga/Gl is 2/3 for better temperature distribution.
Key words: secondary copper sulfide; bioleaching; bio-heap leaching; heat balance; temperature field