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众所周知,泡沫结构和稳定性对矿物浮选回收率和选择性起着重要的作用。然而,定量测定泡沫稳定性,在实验室和工业规模上一直都是一项重要的难题。一个定量动态稳定性测定方法已在实验室规模进行过评价。这种技术是以Bikerman泡沫测试法为基础,使用一根非溢出的泡沫柱定量测定泡沫稳定性。在实验室规模,用这种方法测定出的泡沫稳定性结果与其它方法的测定结果非常接近,其测量值与浮选指标有很好的对应关系。在本文中,用泡沫稳定柱对澳大利亚的Northparke矿山泡沫进行了测试。在不同的操作条件下,测量了动态泡沫稳定系数∑和泡沫稳定系数β,并且与用图像分析法测出的空气溢出分数α进行比较。泡沫稳定柱测出的结果与图像分析获得的结果有相同的变化趋势。研究发现泡沫稳定系数与溢出空气分数成线性关系。试验结果清楚地表明,气体流量、泡沫厚度和起泡剂浓度的变化会引起浮选指标的变化,这主要是由于泡沫稳定性发生了变化。结果表明在低气体流量下,泡沫稳定性较好,从而能够改进浮选指标。研究结果表明,泡沫稳定柱法是一种准确和费用低的测定泡沫稳定性的方法,并且它还可以揭示浮选指标的变化。
It is well-known that foam structure and stability play an important role in mineral flotation recovery and selectivity. However, the quantitative determination of foam stability has always been an important dilemma on a laboratory and industrial scale. A quantitative dynamic stability assay has been evaluated on a laboratory scale. This technique is based on the Bikerman foam test method, which uses a non-spill foam column for quantitative determination of foam stability. In the laboratory scale, the foam stability measured by this method is very close to the results obtained by other methods. The measured value has a good correspondence with the flotation index. In this paper, a foam column was used to test the Northparke foam in Australia. Under different operating conditions, the dynamic foam stability coefficient Σ and the foam stability coefficient β were measured and compared with the air overflow fraction α measured by image analysis. The results obtained with the bubble column have the same trend as the image analysis. The study found that the foam stability factor is proportional to the fraction of overflow air. The test results clearly show that changes in gas flow rate, foam thickness, and bubbler concentration can cause changes in flotation indices, primarily due to foam stability changes. The results show that foam has good stability at low gas flow rates, which can improve the flotation index. The results show that the foam column method is an accurate and low-cost method for the determination of foam stability, and it can also reveal the change of flotation index.