In this study, the relationship between acoustic emissions and hardness of different rock types (model quartz, model calcite, and real iron ore) coupled with binary mix ratios of model quartz and iron ore (1:3, 1:1 and 3:1) was investigated in a laboratory-based AG/SAG mill. The acoustic emission response and sensitivity of the mill were compared, along with its product particle size distribution. Features, such as discrete wavelet transform (DWT), power spectral density estimate (PSDE), and statistical root mean square (RMS) were extracted from the mill acoustic emissions. From the results, it was evident that the mill acoustic emission response can be used to classify different rock hardness and their binary mixtures. Model quartz emitted the highest acoustic response, followed by iron ore and model calcite at the initial stages of grinding (5 min). The results further indicated that as the rock feed sizes reduced, the average mill noise also increased as a function of grinding time. Accordingly, the acoustic emission presented a contrasting effect with model calcite and model quartz emitting the highest and lowest noise emission, respectively. The proportions of different mineral types (model quartz and iron ore) were reflected well in the acoustic emissions. The study has demonstrated that the integration of acoustic sensing techniques in AG/SAG mills can serve as a proxy for online measurement of different rock/ore hardness, for example, as a fast track method to determine the hardness of ores in comparison to the traditional ore grindability procedures, such as Bond work index (BWI) and SAG power index(SPI) tests which can be laborious and time-consuming.

在这项研究中，不同岩石类型（模型石英、模型方解石和真实铁矿石）的声发射与硬度之间的关系以及模型石英和铁矿石的二元混合比（1:3、1:1 和 3:1 ) 在基于实验室的 AG/SAG 磨机中进行了研究。比较了研磨机的声发射响应和灵敏度，以及其产品粒度分布。从轧机声发射中提取特征，例如离散小波变换 (DWT)、功率谱密度估计 (PSDE) 和统计均方根 (RMS)。从结果可以看出，磨机声发射响应可用于对不同的岩石硬度及其二元混合物进行分类。模型石英发出最高的声学响应，其次是在研磨的初始阶段（5 分钟）的铁矿石和模型方解石。结果进一步表明，随着岩石进料尺寸的减小，平均磨机噪音也随着研磨时间的增加而增加。因此，声发射呈现出对比效应，模型方解石和模型石英分别发出最高和最低的噪声发射。不同矿物类型（模型石英和铁矿石）的比例很好地反映在声发射中。该研究表明，声学传感技术在 AG/SAG 磨机中的集成可以作为在线测量不同岩石/矿石硬度的代理，例如，与传统方法相比，作为确定矿石硬度的快速跟踪方法矿石可磨性程序，