我国气流粉碎机节能问题亟待解决

正气流粉碎机与其它粉碎机不同,它是在高速气流作用下,物料通过本身颗粒之间的撞击,气流对物料冲击剪切作用以及物料与其它部件的冲击、摩擦、剪切而使物料粉碎。气流粉碎机是利用物料在高速气流的作用下,获得巨大的动能,在粉碎室中造成物料颗粒之间的高速碰撞、剧烈摩擦,同时高速气流对物料产生剪切作用,从而达到粉碎物料     

气流粉碎技术及其在中药超微粉体中的应用

气流粉碎技术是利用物料在高速气流的作用下，获得巨大的动能，在粉碎室中造成物料颗粒之间的高速碰撞、剧烈摩擦，同时高速气流对物料产生剪切作用，从而达到粉碎物料的目的，它能将原料加工成极细的粉末（〈10μm）。它的优点在于：1、粉碎温度低，可粉碎热敏性、低融点的物料。2、生产周期短，收粉率高。     

超细粉碎对海泡石晶体结构影响的研究

在对海泡石进行超细加工和粒度分析的基础上，利用X射线分析、红外光谱分析研究了高速气流对撞冲击式超细加工对海泡石的晶体结构所产生的影响。研究发现：高速气流对撞冲击式超细粉碎在完成海泡石纤维束分离的同时，也将对海泡石的晶体结构产生一定的破坏作用，导致海泡石的晶胞参数a、b的减小，基本结构单元间以连续点为支点发生一定程度的旋转，从而产生结构孔道畸变。     

超细粉碎对海泡石晶体结构影响的研究

在对海泡石进行超细加工和粒度分析的基础上、利用Ｘ射线分析，红外光谱分析研究了高速气流对撞冲击式超细加工对海泡石的晶体结构的产生的影响。研究发现：高速气流对撞冲击式超细粉碎在完成海泡石纤维束分离的同时，也将对海泡石的晶体结构产生一定的破坏作用、导致海泡石的晶胞参数ａ，ｂ的减小，基本结构韵是以连续占为支点发生一定程度的旋转，从而产生结构孔道畸变。     

气流磨粉碎原理及在钛白粉生产中的应用

引言气流磨作为超细粉碎的一种重要设备,广泛应用于非金属矿物及化工原料的超细粉碎,产品粒度上限取决于混合气流中的固体含量,与单位能耗成反比。气流粉碎产品除粒度细以外,还具有粒度分布窄,颗粒表面光滑、颗粒形状规则,纯度高、活性大、分散性好等特点。由于粉碎过程中压缩气体绝热膨胀产生焦耳-汤姆逊降温效应,因而还适用于低熔点、热敏性物料的超细粉碎。下面就气流磨分类及粉碎原理作一介绍。1气流磨分类工业型气流粉碎自40年代问世以来发展很快,目前工业上应用的气流磨有以下五种类型:1.水平圆盘式(扁平式)气流磨2.循环管式气流磨3.靶式气流磨4.对喷式气流磨5.流化床对喷式气流磨2气流磨粉碎原理气流磨的一般原理:将干燥无油的压缩空气或过热蒸汽通过喷嘴高速喷出,高速射流带动物料作高速运动,使物料碰撞,摩擦而粉碎。被粉碎的物料随气流到达分级区,达到细度要求的物料,最终由收集器收集。没有达到要求的物料,再返回粉碎室继续粉碎,直到达到所需细度并被捕集为止。由于喷嘴附近速度梯度很高,因此绝大多数的粉碎作用发生在喷嘴附近。在粉碎室中,颗粒与颗粒间碰撞的频率远远高于颗粒与器壁的碰撞。也即气流磨中的主要粉碎作用是颗粒之间的冲击或摩擦。虽然气流...     

气流粉碎分级的影响因素

气流粉碎分级是一种先进的制取超细，微粉技术，本文对影响气流粉碎分级的主要因素进行了分析论述，比较了不同结构，不同控制参数的影响作用，提出了匹配工艺参数和择优结构的方法。     

关于气流磨机的几个问题（Ⅰ）

关于气流磨机的几个问题（Ⅰ）孙成林蔡玲北京矿冶研究总院１０００４４国家建材局地质研究所１０００２４关键词：粉碎，气流磨，效率１气流（喷射）磨简史高压气流磨或称喷射磨，是一种较成熟的超细粉碎设备。它是利用高速气流（３００～５００ｍ／ｓ）或过热蒸气（３Ｏ...     

供应信息

<正>昆山密友实业有限公司产品名称:QYF-100实验室用气流粉碎机原理简介:实验室用气流粉碎机的粉碎原理是基于流化床气流粉碎原理,运用高速气流实现干式物料超细粉碎的设备。它由粉碎喷嘴、分级转子、螺旋加料器等组成。物料在高速气流中加速,并在喷嘴交汇处反复冲击、碰撞,达到粉碎效果。被     

密友集团有限公司

正产品名称:QF88实验室用气流粉碎机产品原理:实验室用气流粉碎机的粉碎原理是基于流化床气流粉碎原理,运用高速气流实现干式物料超细粉碎的设备。它由粉碎喷嘴、分级转子、螺旋加料器等组成。物料在高速气流中加速,并在喷嘴交汇处反复冲击、碰撞,达到粉碎效果。被粉碎物料经过分级轮分级,达到细度要求的物料通过分级轮,分离出来,由旋风分离器和捕集器收集,未达到要求的物料继续回到粉碎室粉碎,直到达到要求为止。     

气流粉碎法制备羟基Schiff碱及其理论研究

为实现采用气流粉碎技术制备羟基Schiff碱,以高速气流为载体,使羟基芳香醛和对氨基苯甲酸在粉碎腔中摩擦活化,再通过反复撞击腔体内的固定靶产生巨大的能量交换从而诱导反应的发生。利用傅立叶变换红外光谱、核磁共振、质谱等现代测试技术表征3种含羟基Schiff碱结构,采用半经验计算方法PM3获取原料的前线轨道能量,并对产物几何结构进行优化。结果表明:羟基芳香醛与对氨基苯甲酸反应困难程度随2,3,4-三羟基苯甲醛、间羟基苯甲醛、对羟基苯甲醛依次增大。其理论计算结果与实验测试最佳制备工艺一致。     

Jet mill grinding of portland cement,limestone, and fly ash: Impact on particle size,hydration rate,and strength

While the majority of commercial ordinary portland cement (OPC) is ground using a ball mill or a vertical roller mill, other industries have shown that jet mill grinding can be an alternative approach for grinding materials. This paper investigates the potential application of jet mill grinding for two systems. The first system is a blend of OPC and 15% limestone, and the second system is a blend of OPC and 40% fly ash. It was observed that when jet mill grinding is used, the average particle size of the powders is decreased to approximately 4 μm or less with a narrower particle size distribution than that achieved using ball milling. In addition to evaluating the size and shape of the particles obtained from the jet mill grinding process, this paper focuses on evaluating, using isothermal calorimetry, the effect these changes in particle size and distribution have on the extent and rate of hydration as well as their effect on the compressive strength of cement pastes or mortars.This study also investigated differences between inter-grinding and blending separately ground materials to form an OPC/limestone mixture. Both inter-ground and separately ground OPC/limestone mortars demonstrated an accelerated hydration at early ages accompanied by an increase in early age strength. This appears to be primarily due to the increased surface area of the finer particles that provides more available surface for the hydration reaction. The inter-grinding appeared to be more effective than grinding the materials separately because an improved graded particle size distribution was obtained. The inter-ground OPC/limestone mixture shows accelerated initial hydration at water to powder ratios (w/p, where powder = cement + limestone) of 0.50 and 0.35 when compared with the samples before grinding. At the lower w/p of 0.35, the OPC/limestone mixture appears much more efficient. In the OPC/fly ash mixture, jet mill grinding also accelerates the rate of hydration and strength development.     

燃烧合成氮化硅粉体的超细粉碎

采用燃烧合成氮化硅原始粉料,用球磨的方法进行颗粒超细粉碎,探讨了球磨时间与粉料粒度的关系。结果表明,随着研磨时间的增长,平均粒径减小,但研磨时间的延长到一定时,粒径基本不再减小。该粉料经过24h的球磨后,其平均粒径可降低一个量级,由微米级细化到亚微米级0.5μm左右。粒度分布由原来双峰分布变成了狭窄的单峰分布,颗粒细而均匀。测试了粉体超细粉碎前后的粒度及比表面积,并对其形貌进行了显微形貌观察,讨论了超细过程中的一些现象,对不同球磨机的研磨效果进行了对比。     

采用振动磨制备中药微粉

采用振动磨对三七和水蛭两种中药材进行粉磨实验,研究振动磨工艺参数对粉磨效果的影响。结果表明:水蛭的粉磨效果很好,在短时间内就能达到所要求的微粉粒度;而三七的粉磨效果较差,粉磨时间长且存在无法磨细的中间颗粒。增大磨介填充率、减少物料填充量、减小入磨粒度、增加粉磨时间都可以有效降低最终中药微粉的粒度。     

高压水射流超细粉碎技术的研究与应用

高压水射流粉碎技术的主要特点是效率高、耗能低、拉应力破碎原理、良好的解理性以及能够很好地保护矿物的天然结晶形貌。本文介绍了高压水射流粉碎技术的研究状况 ,以及将高压水射流粉碎技术用于永磁铁氧体原料粉碎工艺的试验研究、制备水煤浆的试验研究 ,以及制备珠光云母粉的工业应用     

Dry Comminution of Silicon Carbide Particles in a Fluidized Bed Opposed Jet Mill: Kinetics of Batch Grinding

This study investigated the batch grinding kinetics of silicon carbide (SiC) particles in a fluidized bed opposed jet mill by population balance modeling. The selection and breakage functions were obtained by the first Kapur function method. The breakage behaviors for various SiC particles obtained under different experimental conditions (such as inlet air pressure, feed load, and distance between nozzle outlet and jet meeting point) in the jet mill were discussed. In addition, a polynomial model was proposed to predict the relation between the Kapur function and the particle size in the jet mill. The product size distributions obtained under various operating conditions from the jet mill could be simulated by modeling.     

DEM Simulation of Particle Comminutionin Jet Milling

A combined discrete element method (DEM) and CFD numerical model was developed to simulate particle comminution in a jet mill. The DEM was used to simulate the motion of the particles in the gas flow. For this, the compressible Reynolds Averaged Navier-Stokes (RANS) equations were used to describe the gas flow field inside a given size's jet mill. Ghadiri's models for breakage and chipping were implemented in the simulation to define the reduction of the particle's size during jet milling. The size distributions of the particles after grinding were obtained numerically. The prediction of the numerical simulation for the median particle size d 50 after grinding was qualitative compared with experimental results for the different operating conditions (i.e., feed rate, angle of grinding nozzles, volumetric rate of grinding air, etc.). The comparison shows good agreement with the experimental observation. The results shows that the feed rate, angle of feeding nozzle, and feeding air's flow rate have more influence on the breakage and chipping of particles in jet milling. In addition, a parametric study was performed to obtain the desired operation conditions.     

DEM Simulation of Particle Comminutionin Jet Milling

A combined discrete element method (DEM) and CFD numerical model was developed to simulate particle comminution in a jet mill. The DEM was used to simulate the motion of the particles in the gas flow. For this, the compressible Reynolds Averaged Navier-Stokes (RANS) equations were used to describe the gas flow field inside a given size's jet mill. Ghadiri's models for breakage and chipping were implemented in the simulation to define the reduction of the particle's size during jet milling. The size distributions of the particles after grinding were obtained numerically. The prediction of the numerical simulation for the median particle size d 50 after grinding was qualitative compared with experimental results for the different operating conditions (i.e., feed rate, angle of grinding nozzles, volumetric rate of grinding air, etc.). The comparison shows good agreement with the experimental observation. The results shows that the feed rate, angle of feeding nozzle, and feeding air's flow rate have more influence on the breakage and chipping of particles in jet milling. In addition, a parametric study was performed to obtain the desired operation conditions.     

气流磨生产过程中喂料速率对粒度的影响

为在流化床式气流磨进行生产时合理选择喂料速率,以获得较好的产品,通过小型气流磨加工滑石粉实验,分析不同分级轮转速下磨腔料位、产品中位径与喂料速率之间的关系,以及喂料速率对产品粒度的影响。结果表明,提高分级轮转速,可以很明显地减小产品中位径;当物料粉碎过程进入稳定状态以后,分级轮的每一个转速都对应一个喂料速率的临界值,在一定的分级轮转速下,把喂料速率调整到最佳值,可以获得粒度更细、分布更窄的产品;喂料速度控制不好将引起分级轮电机过载,产品粒度不稳定,设备产能降低。     

Analysis of grinding kinetics in a laboratory ball mill using population-balance-model and discrete-element-method

Grinding processing consumes a lot of energy in mineral processing, but it is a low-efficiency process in which only approximately 1% of the total energy is used to reduce the actual particle size. Therefore, an efficient operation in the grinding process increases the competitiveness of the production and is an essential for enhancing the energy efficiency of the entire mineral processing procedure.Therefore, the study will focus on to finding a different method to predicting the particle size distribution of the ball mill, by using the PBM which reflects the actual size distributions of ground product and the DEM which can understand the internal particle behavior in the mill chamber. First, the grinding parameters were calculated by applying size distributions of ground product under various conditions to PBM and the behaviors of the particles inside the ball mill obtained through DEM were analyzed to predict the distribution of the impact energy used for grinding. Next, the relational expression between the grinding rate parameter and the normal force applied to the grinding materials was derived. Using the relational expression derived from this study, it was confirmed that the size distributions in other conditions can be predicted.     

一种新型超细粉磨设备的研制

将冲击式超细粉碎机与气流磨的工作原理进行合理集成与创新,提出"品"字型结构设计方案,根据结构需要和工作条件对相应的耐磨材料进行试验以确定最佳材料配对和使用参数,完成新型对撞式超细粉磨分级设备样机的结构设计;采用可编程逻辑控制技术,对系统的工作情况进行实时控制,完成设备的自动控制系统设计;与外购的分级机、滤筒式集尘器、风机等设备组成系统,对系统进行工业性连续运转试验。结果表明,粉磨机及配套设备均达到设计要求,完全满足工业化生产的需要。