Development of fluidized-bed cement calcination process with energy conservation and low pollutant generatic

节能低污染物产生的流化床水泥煅烧工艺开发

基本信息

批准号：
06558066
负责人：
YOSHIDA Kunio
金额：
$ 10.24万
依托单位：
University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06558066/
关键词：
Fluidized bed Cement process Spouted bed Solids circulation Scale-up 石灰石セメント焼成粒子循環

项目摘要

Results are classified into two subjects : (1) elucidation of solids circulation mechanism in spouted beds and (2) development of a scale-up method for fluidiized-bed cement production process.(1) Characteristics of particle circulation in a spouted bed with a draft tubeThe proposed cement production process using fluidization consists of two-stage fluidized beds. : one is upper spouted bed for granulation and the other is lower fluidized bed for calcination. In order to complete the calcination at 1300ﾟC without agglomeration trouble it is essential to produce homogeneous-sized granulus at the upper spouted bed.With this view a spouted bed of 0.205m diameter with a draft tube has been used to study the effect of gas velocity on the behavior of solids circulation. Based on visual observation using a borescope and the analyzes of pressure fluctuation and optical signals it was found that solid particles move from annulus into gas jet to from clusters periodically and are carried upward in the draft tube. At a certain maximum gas velocity, however, solids flow becomes homogeneous and are transported upward without cluster formation.(2) Scale-up of an innovative fluidizd-bed cement production processA pilot-plant with 20 tons per day was scaled up to a larger plant having the capacity of 200 t/d. In this scale-up process the principal specifications of main equipments could be designed on the basis of heat-balance calculation. Both granulating and calcinating beds were scaled up by enlarging their diameters twodimensionally, but several modifications were needed to achieve smooth operation.

结果分为两个主题：(1) 阐明喷动床中的固体循环机制；(2) 开发流化床水泥生产工艺的放大方法。(1) 喷动床中颗粒循环的特征拟议的流化水泥生产工艺由两级流化床组成：一个是用于造粒的上层流化床，另一个是用于煅烧的下层流化床。在 1300°C 且无结块问题的情况下，必须在上部喷动床产生尺寸均匀的颗粒。根据这一观点，使用直径为 0.205m 且带有导流管的喷动床来研究气体速度对固体行为的影响基于使用管道镜的目视观察以及压力波动和光学信号的巢，发现固体颗粒周期性地从环空移动到气体射流中并形成团簇，并在环流中向上携带。然而，在一定的最大气体速度下，固体流变得均匀并且向上输送而不会形成团簇。(2)创新流化床水泥生产工艺的放大生产规模为每天20吨的中试工厂。至日产200吨的大型工厂。在该放大过程中，主要设备的主要规格可以在热平衡计算的基础上进行放大。二维地扩大了它们的直径，但需要进行一些修改才能实现平稳运行。