【作者】 马亮；

【导师】 孙伟；

【作者基本信息】 中南大学 ， 矿物加工工程， 2011， 硕士

【摘要】 本论文利用改进的Hallimond管采用电解浮选法对不同粒级的含钙矿物白钨矿、方解石和萤石的浮选行为进行了研究。以油酸钠作为捕收剂,考察了在不同捕收剂浓度下,矿浆含气率、气泡大小和矿物粒度条件的改变对三种矿物浮选行为的影响。通过高速摄影仪技术对不同电解条件下的气泡性质及与颗粒相互作用进行了研究,并建立了气泡—颗粒相互作用的模型。通过High Speed CCD的研究,发现捕收剂的加入使电解气泡的尺寸减小,同时分布也变得更为均匀；捕收剂浓度对浮选管中形成的气泡簇的直径有很大影响,且对于三种矿物的影响规律是不相同的；气泡簇的直径和其形状系数有一定的对应关系；气泡群的尺寸随着矿浆浓度的增大而增大。试验结果表明：矿浆含气率和气泡大小显著影响三种矿物的浮选回收率。矿浆含气率随着电流强度的增大而增大,气泡量增大的同时,气泡尺寸减小。矿物的浮选回收率随着矿浆含气率的增大而升高；三种矿物的不同粒级在不同气泡尺寸下的浮选是有明显差异的。总体来说,降低捕收剂的浓度,方解石仍有较好的浮选效果,而白钨矿和萤石的浮选回收率下降却较为明显。通过模型建立,将气泡和颗粒的作用过程分为三个阶段。(1)单个的颗粒被单个的气泡捕获；(2)多个颗粒被同一个气泡捕获；(3)气泡群的形成。更多还原

【Abstract】 In this paper, electro-flotation method is applied to study flotation performances of scheelite, calcite and fluorite particles with three different size fractions in a modified hallimond tube. The effects of gas holdup, bubble size and particle size on the interaction between bubble and three minerals containing calcium with three size fractions at various collector concentrations were investigated. Furthermore, the paper is studying on changes in bubble size and the distribution under the different electrolysis conditions, and form of bubble-particle by using high speed video camera. A bubble-particle interaction model is also established in the paper.The study by high speed CCD finds that there is evidence for a decrease in bubble size, and the median bubble size is smaller and the distribution more even in the presence of collector. Bubble clusters occur only when solid particles are present. The collector concentration has a strong effect on the size of the clusters. For different minerals, the influence is not the same. In addition, there is a remarkable correspondence between the clusters diameter and the shape factor. The size of the bubble clusters increases as the solids concentration increases.It is found that gas holdup and bubble size have pronounced effect on the recoveries of minerals. Gas holdup increases obviously with the increase of current intensity, while bubble size decreases. The flotation recoveries of minerals with three size fractions increase with the increasing of slurry gas holdup in the experiments. For the different size minerals, their flotation behavior is diverse in different sizes of bubbles. It is also found that calcite had good flotation behavior, but flotation recoveries of scheelite and fluorite declined obviously at low collector concentration.Through the model establishment, process of bubble-particle interaction was divided into three stages. (1) Capture of individual particles by individual ’clean’ bubbles; (2) Capture of further particles by the particular bubble; (3) Collision of two or three loaded bubbles leads to combining together to form clusters.更多还原