Effect of polymers on compressive rheology of inter-particle structures in mineral processing systems.

随着被处理矿物粒度的减小，矿物分离的难度急剧增加。类似地，固-液分离的后续阶段也随着处理的颗粒的尺寸减小而受到影响。因此，水与细矿物颗粒的分离和再循环仍然是这种细颗粒系统中的主要问题。由于目前开采的矿石通常需要超细粉碎以实现有效分离，因此该行业似乎必须开发新的方法来处理越来越多的细颗粒。 拟议的研究计划的总体目标是提高我们处理这些加工问题的能力，以及聚合物是否可以更好地用于克服这种粒度相关的分离性限制。聚合物吸附的影响，无论是物理或化学，对颗粒间结构的性能将被确定。还需要调整和开发新的测试方法，以获得有关细颗粒物系统的微观和宏观特性的信息。缺乏适当的现场测试方法是我们无法看到沉积物结构内部以及这些结构如何对各种处理作出反应的主要原因。在一个新的应用中，实验计划将涉及X射线计算机断层扫描（CT），用于可视化和分析沉积物的内部结构，以及在固液分离过程中沉积物结构在压力下如何变化。沉积物特性随时间的变化也可以用激光反向散射法监测。后向散射法可用来估算沿沉积物高度沿着的固体含量。沉积物中颗粒/絮体的表面充电特性将采用流动电位法进行探测。沉积物对外力的抵抗力和沉积物释放的水量将通过压缩流变学研究，结合CT结果，这将为絮凝矿物悬浮液的脱水行为提供新的见解。将使用超浓缩和粘度技术表征测试的聚合物。设想所有工作将在各种pH值和离子强度条件下使用一系列不同的聚合物-矿物系统进行。* 矿物加工业经常受到尾矿设施对环境影响的审查，以及不太理想的水回收做法。尽管如此，在可预见的未来，水仍将是所有用于细矿物颗粒分离的技术的工艺介质。据信，这一计划的结果将有助于更智能和更有效的方法来利用水。这些数据也应该适用于使用聚合物和处理固液悬浮液的其他行业。

The difficulty of mineral separation sharply increases as the particle size of the processed minerals decreases. Similarly, subsequent stages of solid-liquid separation also suffer as the sizes of the treated particles decrease. As a result, separation and recycling of water from fine mineral particles remains a major problem in such fine particle systems. As presently-mined ores often require ultra-fine grinding for efficient separation, it appears that the industry will have to develop new approaches to deal with the increasing amounts of fine particles.**** The overall objectives of the proposed research program are aimed at enhancing our ability to deal with these processing issues, and whether polymers can better be utilized to overcome such particle size-related separability limits. The effect of polymer adsorption, whether physical or chemical, on the properties of interparticle structures will be determined. A need also arises to adapt and develop new testing methodologies to obtain information about the micro- and macro-properties of fine particulate systems. The lack of appropriate in-situ testing methods is largely responsible for our inability to look inside sediment structures, and how those structures respond to various treatments. In a novel application, the experimental program will involve x-ray computed tomography (CT) for visualizing and analyzing internal structures of sediments, and how the sediment structure changes under pressure during solid-liquid separation. Changes in sediment properties as a function of time can also be monitored using laser light back-scattering. The back-scattering method allows estimation of the solids content to be made along the sediment height. The surface charging characteristics of particles/flocs in sediments will be probed with the streaming potential method. The resistance of sediments to external forces and the amount of water released by the sediments will be researched through compressive rheology, which in combination with the CT results should provide a new insight into the dewatering behavior of flocculated mineral suspensions. The tested polymers will be characterized using ultracentrifuging and viscosity techniques. It is envisaged that all the work will be performed using a range of different polymer-mineral systems, under various pH and ionic strength conditions.**** The mineral processing industry often comes under scrutiny for the environmental impact of tailings facilities, and for the less-than-optimal water recycling practices. Nevertheless, water will still be the process medium in the foreseeable future for all technologies used for separation of fine mineral particles. It is believed that the results of this program will contribute to smarter and more efficient approaches to water utilization. The data should also be applicable to other industries using polymers and handling solid-liquid suspensions.***