RefluxClassifier分离细颗粒的技术发展与应用前景

Development and Application Prospect of Reflux Classifier for Fine Particles Separation

矿石综采技术带来诸多便利的同时,也导致了矿石中细颗粒比例增多。细颗粒分离成为了国内外矿物加工领域面临的难题。由于细颗粒质量小、比表面积大、表面能高、容易团聚,进而难以有效分离。本世纪初,由澳大利亚学者Galvin所研制的RefluxClassifier(回流分级机,简称RC)作为一种新型重力分选设备进入到矿物加工设备行列。该设备由液固流化床与倾斜通道组成,分为垂直段与倾斜段,具有操作简单、成本低廉和高效节能等优点。据研究,RC因其特殊的结构与工作机理可以有效解决细颗粒分离问题。本文首先归纳了国内外有关RC的理论研究,详细描述了RC倾斜段中颗粒在流体中的运动状态,阐明了倾斜通道内颗粒运动与流体流动特性之间的关系,简要分析了颗粒性质与流体之间的力与速度关系。此外,本文对目前现有RC的水速预测模型(经典动力学模型、经验模型、弱化粒度模型、平衡模型)进行了总结,并综合分析了各模型的适用范围。结合试验案例,介绍了RC在煤炭、黑金属、砂石骨料等领域的应用现状,举例分析不同试验条件下RC对细颗粒回收的分离情况。最后结合我国资源现状与现代设备发展趋势,提出如何深入优化RC分选理论模型、拓展更广阔的应用领域是国内外学者的长期研究目标,并展望RC在工业范围内的全面推广。

The comprehensive mining technology of ore brings many conveniences,but it also leads to an increase in the proportion of fine particles in the ore.Fine particle classification has become a challenge in the field of mineral processing both domestically and internationally.Due to the small mass,large specific surface area,high surface energy,and easy aggregation of fine particles,effective separation is difficult.At the beginning of this century,the Reflux Classifier(RC),developed by Australian scholar Galvin,entered the ranks of mineral processing equipment as a new type of gravity sorting equipment.This equipment consists of a liquid-solid fluidized bed and an inclined channel,divided into vertical and inclined sections.It has the advantages of simple operation,low cost,and high efficiency and energy conservation.According to the research,RC can effectively solve the problem of fine particle separation due to its unique structure and working mechanism.This article first summarizes the theoretical research on RC at home and abroad,describes in detail the motion state of particles in the fluid in the inclined section of RC,clarifies the relationship between particle motion and fluid flow characteristics in the inclined channel,and briefly analyzes the force and velocity relationship between particle properties and fluid.In addition,this article summarizes the current water velocity prediction models for RC,including classical dynamic models,empirical models,weakened particle size models,and equilibrium models,and comprehensively analyzes the applicability of each model.Based on experimental cases,the current application status of RC in the fields of coal,black metal,sand and gravel aggregates was introduced,and examples were given to analyze the separation of fine particle recovery by RC under different experimental conditions.Finally,based on the current situation of resources in China and the development trend of modern equipment,proposal is given on how to deeply optimize the theoretical model of RC sorting and expand its wider application fields is the long-term research goal of domestic and foreign scholars,and the comprehensive promotion of RC in the industrial scope is also expected.