【作者】 孟祥利；

【导师】 胡岳华； 孙伟；

【作者基本信息】 中南大学 ， 矿物加工工程， 2011， 硕士

【摘要】 本文研究了表面活性剂对微细粒一水硬铝石颗粒(-10μm)与气泡相互作用的影响。论文首先探究了一种测量气泡尺寸的方法：采用电解水法产生气泡,电解浮选装置与显微图像采集装置连接,浮选过程经高速摄影仪(high speed charge-coupled device, CCD)采集并记录后,照片经过SigmascanPro 3.5处理转化成数字信息。这些数字信息再经过数据筛选和MATLAB处理后,形成能反映气泡性能的统计性数据。应用上述方法,本文详细考察了表面活性剂种类和浓度对浮选气泡大小的影响,及其对气泡与一水硬铝石颗粒相互作用的影响。实验结果表明：分散剂六偏磷酸钠和碳酸钠的添加和浓度的改变对气泡大小没有影响。分散剂用量很低时,矿粒呈虚的网状絮团形式出现,并且与气泡粘附上升。随着分散剂浓度的增加,矿浆中的絮团逐渐减少,絮团与气泡的粘附也越来越少。分散剂浓度达到40 mg/L后,矿浆中矿粒分散均匀,此时矿粒不与气泡粘附。当分散剂浓度大于此值后,分散剂浓度的增加对矿浆分散的改变不明显。两种起泡剂二丙二醇甲醚(dipropylene glycol monomethyl ether, DPM)和口三丙二醇丁醚(tripropylene glycol n-butyl ethel, TPnB)的实验结果均显示：随着起泡剂浓度的增加,气泡尺寸迅速减小；当起泡剂浓度达到一定值后,气泡尺寸趋于恒定,与起泡剂浓度无关。起泡剂用量很低时,气泡基本不与矿粒粘附；随着起泡剂浓度的增加,气泡上粘附的矿量逐渐增多。当起泡剂浓度达到一定值后,气泡上粘附的矿量达到最大。捕收剂油酸钠和十二烷基二甲基苄基氯化铵(1227)的实验结果表明：随着捕收剂浓度的增加,气泡尺寸有所减小,但与起泡剂相比其对气泡尺寸变化的影响较小。随着捕收剂浓度的增加,气泡上粘附的矿量先增加后减小,直至气泡与矿粒完全不粘附；在捕收剂浓度达到一定值后,气泡开始产生结串现象,相应气泡串的上升速度也明显降低。更多还原

【Abstract】 This paper investigated the interaction between unltrafine diaspore particles and bubbles in flotation process with the presence of surfactants. A self-designed electrolytic cell was chosen as the reaction environment with sodium chloride (NaCl) as the electrolyte. Constant current which was supplied by a self-designed power supplier guaranteed the total original gas volume. Even aperture of the cathode material guaranteed the original bubble size.Firstly, this paper successfully explored a method to measure bubble size in flotation process. Bubble generating equipment was connected with a high speed charge-coupled device (CCD), which was used to capture and record flotation process. The obtained pictures were processed by software Sigmascan Pro.3.5 to thanslate the picture information into data information, than after data cleaning, MATLAB was used to find the statistical results of bubble size distribution.In experiments, this paper focused on the study of effect of surfactants kinds and concentration on bubble size, and influence of surfactants to interaction between bubbles and dispore particles. Results were obtained as follows:The effects of dispersants sodium hexametaphosphate and sodium carbonate were measured at the same condition. It was indicated that the presence of dispersants did not have evident effect on bubble size. Investigation of interaction between bubbles and particles denoted that dispersants dispersed pulp effectively. Dispersion effect was the best when dispersant dosage was 40 mg/L, above which the increment of the dispersant concentration showed negligible effect on pulp dispersion.The effects of frothers dipropylene glycol monomethyl ether (DPM) and tripropylene glycol n-butyl ethel (TPnB) were measured at the same condition. It was shown that bubble size decreased with the increment of the frother concentration when which was low. When the concentration reached some inflexion, bubble size reached the lowest point, after which bubble size remained the same, regardless of the increment of the frother concentration.2×10-4 mol/L and 5×10-2 mol/L were found to be the inflexions of their change to bubble size. Experimental results of interactions between bubbles and diaspore particles revealed that the mineral quantity attached on bubbles increased with the increment of the frother concentration.The effects of collectors sodium oleate and dodecyl dimethyl benzyl ammonium chloride(1227) were measured at the same condition. It was noticed that the presence and concentration increment of collectors decreased bubble size, but not as obviously as frothers did. The investigation of interaction between bubbles and particles indicated that with the increment of collector concentration, the amount of the minerals attaching to bubbles firstly increased then declined after the dosage reached some point. And it also showed that when collector dosage was high, bubble agglutination increased, meanwhile the rising speed of bubbles declined.更多还原