落重试验测定矿石粉碎特性参数

为了科学、准确地进行碎磨设备选型,并确定合理的碎磨工艺流程,对国际上较盛行的自磨/半自磨工艺中物料粉碎特性参数的测定方法——JKTech落重试验法进行了系统介绍,在此基础上,采用JK落重试验仪和磨蚀粉碎试验设备,测定了承德某铁矿3个矿样的冲击粉碎参数A和b以及磨蚀粉碎参数Ta。将试验结果与数据库数据比较,可以得出:13个矿样的粉碎特性十分接近,都属于软-中软矿石。2矿样在破碎能为2.5、1.0 kWh/t时,颗粒的抗冲击破碎能力随颗粒粒度的增大而下降,且破碎能越大颗粒抗冲击破碎的能力下降越显著;当比破碎能为0.25kWh/t时,颗粒的抗冲击破碎能力随颗粒粒度的增大而上升,即随比破碎能下降,颗粒粒度-t10关系曲线的斜率变小。3试验结果可以成功用于磨机与破碎机处理量和能耗的计算以及自磨/半自磨流程设计和模拟计算。因此,JKTech落重试验所测得的粉碎特性参数不仅可以判断矿石性质,也可作为设备选型和流程确定的依据。     

落重试验在碎磨工艺设计与优化中的应用

落重试验作为一种用于自磨(半自磨)机选型计算的矿石试验方法近些年来在国内得到越来越多的应用。简要介绍这种与粉碎数学模型密切相关的试验方法、物料特性参数及其在碎磨工艺设计与优化上的应用。     

SCSE——表征矿石半自磨可磨度的新指标

JK落重试验及SMC试验作为测定矿石粉碎特性的试验方法在半自磨机选型和工艺条件优化中得到越来越多的应用。由JK落重试验或SMC试验获得的物料特性参数A和b是一种建立在特定粉碎数学模型基础之上的模型参数,这两个参数本身没有明确的物理意义,尽管其乘积A×b可作为衡量矿石抵抗冲击粉碎能力的一个指标,但A×b取值大小的工艺意义只有通过模型计算结果才能体现出来。为弥补这方面的不足,JKTech公司和SMCT公司新近联合推出了一种表征矿石半自磨可磨度的新指标——SCSE值。在综述JK落重试验、SMC试验以及利用JKSim Met软件进行半自磨磨矿流程模拟的方法和原理的基础上,介绍了这个新指标的定义、意义及局限性。     

粒度小于13.2 mm矿石颗粒的冲击粉碎试验研究

JK落重试验是测定矿石粉碎特性参数的一种方法。标准落重试验的试样粒度范围为-63.0+13.2 mm。在利用JKSim Met软件进行自磨/半自磨粉碎模拟时,由此试验获得的矿石特性参数被默认地运用于所有粒度颗粒的粉碎。以华东某金矿矿石为对象,进行了粒度小于13.2 mm矿石颗粒的冲击粉碎试验研究。结果表明,此矿石物料的粉碎存在粒度效应,随着粒度的减小,颗粒抵抗冲击粉碎的能力增大。另外还发现,试料制备时的破碎次数对颗粒的粉碎效果也有影响。     

落重试验测定内蒙古某铅锌矿石粉碎特性参数

通过标准落重试验和磨剥试验对内蒙某铅锌矿石进行了磨矿特性参数测定,测定结果表明,该矿石属于中软矿石,在试验粒度范围内(13.2~63mm)矿石抵抗冲击粉碎的能力随颗粒粒度的减小而增大。这些矿石特性参数为此铅锌矿132万t/a选矿厂碎磨流程的"半自磨-球磨"方案进行流程模拟和磨机选型提供了依据。     

落重试验测定内蒙古某铅锌矿石粉碎特性参数

通过标准落重试验和磨剥试验对内蒙某铅锌矿石进行了磨矿特性参数测定,测定结果表明,该矿石属于中软矿石,在试验粒度范围内(13.2~63mm)矿石抵抗冲击粉碎的能力随颗粒粒度的减小而增大。这些矿石特性参数为此铅锌矿132万t/a选矿厂碎磨流程的“半自磨-球磨”方案进行流程模拟和磨机选型提供了依据。     

自磨技术的发展及其有关总是的评述（之二）

5　有关问题的评述5 1　关于自磨与常规磨矿与常规碎磨流程比较 ,自磨的主要优点是 :能接受较大的给矿粒度 (最大粒度一般为 3 50～ 2 0 0ｍｍ ) ,因此可以取代中、细破碎及粗磨作业 ,减少生产环节和粉尘污染 (对湿式自磨 ) ,简化车间组成和占地面积 ;具有一定的选择性碎磨作用 ,减少矿石过粉碎 ,有利于分选 ;不耗或少耗磨矿介质 ;对含水含泥较多的粘性矿石采用湿式自磨可以避免常规流程中破碎、筛分等环节的堵矿问题。自磨流程的主要缺点是 :电耗一般比常规磨矿高 ;设备作业率比球磨低 ;对给矿粒度及其可磨性变化比较敏感 ,生产易波动 ,操…     

国外自磨技术的进展(一)

国外自50年代应用自磨以来，自磨技术不断完善和发展。本文对国外自磨技术进展的有关情况做以介绍，包括自磨工艺的应用、自磨流程、自磨机长径比、自磨试验和设计等方面问题，其中着重阐述了在一些重要技术环节和技术观点上的进展。     

转摆磨模拟实验

一、简介转摆磨是从离心磨或行星磨发展而来的,它克服了离心磨的机械局限及给排料困难的缺点,其单位容积的粉碎率高,为常规管磨机的50～100倍。这种磨机体积小,磨矿能力强,因而广泛用于硬物料的细磨或中等粒度物料的高速自磨。二、转摆磨(Nutating mill)的特点转摆磨结构如图1,它可看作是在比重力     

自磨技术的发展及其有关问题的评述(之一)

本文从国内外自磨工艺应用、自磨流程改进、自磨设备结构及其大型化的进展等方面论述了自磨技术的发展 ,并对自磨工艺的应用、自磨试验、自磨机计算以及自磨机长径比等有关问题进行了评述     

Überblick über Methoden der Mahlbarkeitsprüfung

The paper covers a selection of grindability tests described in literature for the characterization of the comminution behaviour of mineral matter down to a minimum particle size of the comminution product of approximately 0.02 mm. The test rigs, the test work, the characterization of the grindability and the correlation to the full scale apparatus are lined out. The test methods for impact, compressive and frictional stress with or without measurement of the energy input are commented and added by the methods developed at the Institute of Mineral Processing. Emphasis is laid on the method of the Optimized Comminution Sequence by means of which material parameters can be acquired rather independently from the influence of machinery. Three results from the extensive test-work with a comminution sequence covering a size range from 200 to 0.2 mm support Prof. H. J. Steiner’s concept of the Natural Breakage Characteristic and the limiting case of linear correlation between new created surface and energy input in the case of energy optimized comminution.     

本钢歪头山矿石碎磨特性参数研究

以本钢歪头山铁矿石为试验物料，采用JK落重试验和Bond球磨功指数试验研究了矿石的碎磨特性参数。结果表明：冲击粉碎参数A为65.53，b为1.06，A×b为69.46；磨蚀粉碎试验获得的矿石磨蚀系数ta为0.72；相对密度测定试验获得的矿石相对密度为3.31。Bond球磨功指数试验获得的球磨功指数W_ib为7.64 kWh/t，碎磨特性参数和Bond球磨功指数表明，歪头山矿石属于软矿石范畴，其抗冲击破碎能力和抗磨蚀能力都比较弱，矿石中没有难磨粒子。     

高压辊磨机粉碎数学建模和计算机模拟研究进展

介绍高压辊磨机粉碎数学模型的研究进展,以及应用粉碎数学模型通过计算机模拟计算进行工业型高压辊磨机粉碎效果预测、粉碎回路流程设计和工艺条件优化的研究进展。     

铁矿石物料粒间粉碎的数学建模

利用三种铁矿石物料的窄粒级颗粒床压载粉碎试验结果验证先前建立的一种关于粒间粉碎的物料模型对这些矿石物料的适用性,并且利用这三种物料的宽粒级颗粒床压载粉碎试验结果进行该物料模型的参数求解研究。结果表明,实验室颗粒床压载粉碎试验与数学建模方法相结合是研究和优化矿石物料粒间粉碎的一种有效方法。     

Predicting the overall specific energy requirement of crushing,high pressure grinding roll and tumbling mill circuits

In a previous paper [Morrell, S. 2008a. A method for predicting the specific energy requirement of comminution circuits and assessing their energy utilisation efficiency. Minerals Engineering 21(3), 5–9] an approach was described which enabled the specific energy of tumbling mills such as Autogenous (AG), Semi-autogenous (SAG) and ball mills to be estimated from laboratory-derived ore characterisation data. The following paper extends this approach to encompass jaw, gyratory and cone crushers as well as High Pressure Grinding Rolls (HPGR). The technique is applied to three different comminution circuits and their overall specific energies are compared. All of the calculations involved are described in detail in an appendix.     

高压辊磨机选型试验的研究现状

结合高压辊磨机中物料粉碎机理,介绍了影响高压辊磨机粉碎效果的关键因素,评述了高压辊磨机设备选型试验的研究现状。高压辊磨机粉碎物料的效果主要受物料性质、辊压机工作参数及粉碎工艺等的影响。通过小型及半工业型高压辊磨机粉碎试验能够为高压辊磨机的设备选型和流程设计提供依据,但试验过程相对复杂。颗粒床活塞压载试验和数学建模尽管能够对矿石料层粉碎的工作压力、比能耗、产品粒度分布等进行有效预测,但和高压辊磨机设备选型的经验公式一样均需要对其适用性进行验证。指出高压辊磨机未来的研究方向为粉碎过程中能量传递模型、矿石碎磨特性及对分选工艺影响等的理论基础研究,以及高压辊磨机在选矿流程中的数值模拟研究。     

Aufbereitungstechnische Untersuchungen als wesentliche Grundlage für die Verfahrensgestaltung in Aufbereitungsanlagen

The authors are university teachers commissioned with giving prospective process engineers in the framework of their academic training the tools they need to execute future planning tasks responsibly and competently. Finding the processing method most suitable for a specific task is preferably based on a systematic raw material characterization at laboratory scale. This will usually lead to a better overall relation of costs and gain of the investigation, as it provides valuable information for starting the following tests of larger scale. In comparison to expensive pilot scale tests, laboratory testing technology has several advantages, e.g. easy avoidance of contamination, more versatile and accurate means of measurements, and wide variation of test parameters while requiring only a very small amount of test material. The laboratory methods result in well-defined characteristic values such as breakage behaviour, comminution resistance, intergrowth conditions and physical properties of the particles to be exploited for separation. In conjunction with the separation characteristics of specific processing machines they may provide predictive balances of the separation results. They clearly state the possibilities and limitations of the results to be expected in large scale operations. This article demonstrates the importance of this methodology of investigation. It sketches the individual tests available and exemplifies them.     

A more sustainable approach to assessing comminution efficiency

The Bond operating work index is in common use for assessment of comminution efficiency. This method was developed for rod and grinding ball mill circuits and is not well suited to AG/SAG mills or the wide range of comminution devices now in common use.Traditional measures of efficiency only consider the net motor power of the drive unit. However, ancillary processes such as materials handling and classification can consume a substantial fraction of motor power.Wear resistant liners and grinding media are also consumed by the comminution process. These consumables themselves require substantial energy to mine, refine and to manufacture. This embedded (or indirect) energy can be of similar order to motor power.This paper outlines several ways to estimate of comminution efficiency. These methods can be applied to a wide range of equipment. The paper also describes how to estimate indirect energy consumption.