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先前的研究表明浮选机中浮选总速率常数K与气泡表面积通量Sb之间存在着紧密的联系,且这一联系与浮选机叶轮类型无关。最近从处理同一给矿的250L浮选槽和3m~3浮选槽的研究中得到:只要浮选泡沫层厚度与浮选机内表层气体流速之比一致,两浮选槽表现出相同的k-Sb联系,这一比例称为泡沫滞留时间,τfg。本文通过对这些结论再次评估和解释,来检测泡沫滞留时间τfg对浮选动力学的影响。研究发现K对τfg呈指数形式减小但这一联系与浮选槽尺寸有关,因此不能直接用于比例放大。当τfg被特定的浮选槽尺寸来除而用来解释不同尺寸浮选槽中泡沫传输距离的影响时,K与“比泡沫滞留时间”的联系更适于试验数据且这一联系与浮选槽的尺寸无关。最后当用在精矿流量基础上计算出的泡沫滞留时间τfg来评估试验结果时,发现τfg又更适于试验数据。讨论了这些联系在浮选槽模拟和比例放大方面的应用情况。
Previous studies have shown that there is a close relationship between the total rate constant of flotation flotation in the flotation machine and the flux of Sb on the surface of the bubble, and this relationship has nothing to do with the type of flotation machine impeller. Recent studies from the 250L flotation cell and the 3m-3 flotation cell handling the same feedlot have shown that as long as the flotation foam layer thickness is consistent with the flotation machine internal surface gas flow rate, the two flotation cells exhibit the same k -Sb link, this ratio is called the foam residence time, τfg. In this paper, we reassess and explain these conclusions to test the effect of foam residence time τfg on flotation kinetics. It has been found that K decreases exponentially with respect to τfg but this correlation is related to the size of the flotation cell and therefore can not be directly used for scaling up. When τfg is divided by the size of a particular flotation cell to account for the effect of foam transport distances in different sizes of flotation cell, the relation between K and “bubble residence time” is more suitable for experimental data Flotation tank size has nothing to do. Finally, when the test results were evaluated using the foam retention time τfg calculated on the basis of the concentrate flow rate, τfg was found to be more suitable for the test data. The use of these connections in flotation tank simulation and scaling up is discussed.