CMP230X-12AW型挤压造粒机组控制系统的改造

对日本制钢的CMP230X-12AW型挤压造粒机组的控制系统进行了全面升级改造.文中给出了改造方案,并对控制系统的功能、显示界面、操作系统进行说明.改造后,提高了生产效率和系统稳定性.     

差速开关在机组离合器控制中的应用

介绍摩擦离合器的基本功能和其在造粒机组中的应用,剖析了PLC控制离合器的相关功能。针对离合器控制系统的具体问题,将原PLC控制的差速联锁改为差速离合开关控制,超驰掉了开车时的误联锁,实现了差速联锁功能。     

尿素造粒塔的腐蚀与防护

尿素造粒塔是尿素生产过程中的大型构筑物,它采取的防腐蚀措施的好坏直接影响了它的使用寿命,本文介绍了云维集团沾化分公司尿素造粒塔的维修经验.     

50 kt/a转鼓造粒生产硫基复合肥

7kt/a磷酸装置与氯化钾低温转化相结合 ,经特制的管道反应器 ,转鼓造粒 ,可生产 14 14 14 ,1515 15 ,16 16 16 ,氯根小于 3% (也可小于 1.5 % )的 S NPK。介绍该工艺流程、主要设备、工艺条件。试生产取得的效果 :产量达 7～ 7.5 t/h(设计能力 5 0 kt/a) ,含氮量最高可达 17% ,颗粒圆整光滑 ,成球率达 70 %～ 80 % ,较喷浆造粒节电 15～ 2 0 k W· h/t,节省投资 30 0～ 5 0 0万元 ,产品规格可调性大。     

Effect of scale of operation on granule strength in high shear granulators

Results of a study on the influence of operation scale and impeller speed of high shear mixer granulators on the strength of granlues are reported in this paper. Calcium carbonate particles have been granulated in four scales of a geometrically similar high shear granulator (Cyclomix) with 1, 5, 50 and 250 L capacities. For the smallest scale, the effect of a small deviation from geometric similarity was also investigated. An aqueous solution of polyethylene glycol was used as the binder. Three scaling rules of constant tip speed, constant shear stress and constant Froude number have been used to determine the impeller speed for the different scales of the granulators. The granules produced in these experiments have been dried and tested for strength using side crushing test method. The data have then been analysed and compared. Operation of granulators according to the constant tip speed rule produces granules with a similar strength for all four scales, followed by a similar trend for the constant shear stress rule, albeit to the less extent. The constant Froude number rule produces a heterogeneous strength distribution and is not a suitable criterion for scaling-up of high shear granulators. The distribution of granule strength has been fitted to the normal, log-normal and Weibull distributions. Weibull distribution fits the data well for the constant tip speed operations.     

Three-dimensional computational fluid dynamics (CFD) study of the gas–particle circulation pattern within a fluidized bed granulator: By full factorial design of fluidization velocity and particle size

The fluidization velocity and mean particle size were selected to be numerically investigated pertaining to their effects on the gas–particle circulation pattern within a fluidized bed granulator by three-dimensional computational fluid dynamics (CFD) simulation applying an Eulerian–Eulerian two-fluid model. The CFD simulations were designed by full factorial design method and the developed CFD model was experimentally validated. The fluidization process was proved to reach a quasi-steady state. The gas–particle circulation pattern and particle concentration distribution were analyzed based on fluidization velocity and mean particle size. A mathematical model was developed to provide guidance on how to change fluidization level during one experiment.     

有机型复合颗粒肥生产线设计

有机型复合颗粒肥生产线用于加工以有机肥作基本介质，混配一定比例无机成分，适合各种经济作物养分和施肥要求的颗粒状全价营养肥料。     

塔式熔体造粒生产长效复合肥的技术总结

针对传统的复合肥生产中喷头易堵塞等问题,介绍了高塔熔体造粒复合肥生产中添加生物酶抑制剂抑制肥料中各有效养分在土壤中流失,采用双轴差动旋转喷淋造粒器的造粒原理、生产过程和装置特点,通过模拟试验得出滴珠在Φ4mm时的塔高,提高了开车率.     

提高硝酸磷肥产品粒度合格率的方法

探讨从中和料浆浓缩工序来的熔体在硝酸磷肥双轴造粒机中的造粒机理；分析影响造粒的因素（化学性质、返料比、温度、熔体的含水量、返料的粒度分布、物料停留时间）；介绍成粒曲线及其应用（即生产中如何通过改变一些操作条件使成粒点处于成粒曲线范围内）；最后介绍天脊煤化工集团公司造粒控制现状及其对策。     

An investigation on process of seeded granulation in a continuous drum granulator using DEM

Numerical simulation of wet granulation in a continuous granulator is carried out using Discrete Element Method (DEM) to discover the possibility of formation of seeded granules in a continuous process with the aim of reducing number of experimental trials and means of process control. Simple and scooped drum granulators are utilized to attain homogenous seeded granules in which the effects of drum rotational speed, particles surface energy, and particles size ratio are investigated. To reduce the simulation time a scale-up scheme is designed in which a dimensionless number (Cohesion number) is defined based on the work of cohesion and gravitational potential energy of the particles. Also a mathematical/numerical method along with a MATLAB code is developed by which the percentage of surface coverage of each granule is predicted precisely. The results show that use of continuous granulator for seeded granulation is promising provided that a high level of shear is considered in the granulator design, i.e. using baffles inside drum granulators is essential for producing seeded granules. It is observed that the optimum surface energy for seeded granulation in scooped granulator (used in this study) with rotational speed of 50 rpm is 3 J/m², which is close to the value predicted by the concept of Cohesion number. It is also shown that increasing the seed/fine size ratio enhances the seeded granulation both quantitatively (60% increase in seeds surface coverage) and qualitatively (more homogeneous granules).