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矿物悬浮液在低固体含量时显示出牛顿流特性。然而,当固体含量增加时,它向非牛顿流转变。牛顿流的粘度不随切变速率而改变。但是对非牛顿流,粘度随切变速率而改变。因而,如果矿浆是非牛顿的,在固定的切变速率下测定流体的粘度是没有价值的。水力旋流器内不同的点具有不同的切变速率。这样在企图确立粘度和处理效率关系以前先确定悬浮液的流体特性是非常重要的。开发了区分流体类型变化的新技术,包括了二种粘度计:同轴园柱型粘度计(测定低切变速率时的表观粘度)和振动球型粘度计(测定高切变速率时的表观粘度)。采用这二种仪器测定迅速沉降的矿物悬浮液时都采取了一些特殊的预防措施。由于振动球型粘度计和转动粘度计相比应用于高得多的切变速率,两者结合使用可确定切变速率和粘度的关系。使用磨矿后的石英(-65μm85%),浓度为10-70%。用二种粘度计同时测定矿浆样品的粘度,并对结果进行比较。采用这种技术发现,石英矿浆在浓度70%以前都处于牛顿流状态。Methocel和Cellosize聚合物溶液显示出明显的非牛顿流特性。证明了石英矿浆不存在非牛顿流特性,否则,它会被这种技术检测出来。
Mineral suspensions show Newtonian properties at low solids. However, as the solids content increases, it transitions to non-Newtonian flow. The viscosity of Newtonian flow does not change with the shear rate. But for non-Newtonian flow, the viscosity changes with the shear rate. Thus, if the pulp is non-Newtonian, it is of no value to determine the viscosity of the fluid at a fixed shear rate. Different points within the hydrocyclone have different shear rates. It is therefore important to determine the fluid properties of the suspension before attempting to establish the relationship between viscosity and process efficiency. New technologies have been developed that differentiate fluid type changes, including two types of viscometers: coaxial cylindrical viscometers (apparent viscosities for low shear rates) and vibrating ball type viscometers (for high shear rates Apparent viscosity). Some special precautions have been taken when using these two instruments for the rapid settling of mineral suspensions. Since the vibrating ball viscometer applies a much higher shear rate than the rotational viscometer, a combination of the two can determine the relationship between shear rate and viscosity. After grinding the quartz (-65μm 85%), the concentration of 10-70%. The viscosities of the pulp samples were simultaneously determined with two viscometers and the results were compared. Using this technique, it was found that the quartz pulp was in Newtonian flow until 70% of its concentration. Methocel and Cellosize polymer solutions show significant non-Newtonian properties. It is proved that there is no non-Newtonian flow in quartz slurry, otherwise, it will be detected by this technique.