沸腾床内液相的返混特性  

Backmixing characterization of liquid phase in ebullated bed reactor

作　　者：黄子宾[1] 朱闯杰 黄岩[1] 程振民[1] 杨涛[2] 刘建锟[2] 方向晨[2] 

机构地区：[1]化学工程联合国家重点实验室,华东理工大学化工学院,上海200237 [2]中国石化抚顺石油化工研究院,辽宁抚顺113001

出　　处：《化工学报》2017年第2期630-636,共7页CIESC Journal

基　　金：国家自然科学基金项目(21306045,21676085,21076072);中央高校基本科研业务费专项基金项目(222201314014)~~

摘　　要：在直径0.3 m、总高7.2 m的沸腾床反应器内采用脉冲示踪法研究液相的返混特性。实验中分别以空气和水作为气相和液相,气体操作速度从0.26 cm·s-1变至12.97 cm·s^(-1),液体表观速度固定为0.86 cm·s^(-1)。采用三氧化二铝颗粒作为固相,其中固体颗粒的平均粒径为0.4 mm,床层固体含量(体积分数)从0变至42.9%。实验结果表明,在所有考察条件下每组响应曲线均存在明显的长拖尾现象,沸腾床内存在剧烈的液体返混现象。尝试采用带回流的多釜串联模型拟合实验数据,结果表明模型预测值与实验数据吻合得非常好,其中拟合得到的全混釜个数N为8,回流比k从1.320至4.218不等,方差预测值与实验值之间的最大误差不超过+18%。The liquid backmixing characteristics were investigated experimentally using pulse tracing technique in an ebullated bed reactor of 7.2 m in height and 0.3 m in diameter. Air and water were used as the gas and liquid phases, respectively. The superficial gas velocity ranged from 0.26 to 12.97 cm·s^（-1）, while the liquid velocity was fixed at 0.86 cm·s^（-1）. The particles of aluminum oxide with an average diameter of 0.4 mm were used as the solid phase. All experiments were carried out under the solids holdup from 0 to 42.9%（vol）. The results showed that each response curve demonstrated obvious long tail phenomenon, which implied that there existed evident liquid backmixing in the ebullated bed reactor at different operating conditions. A tanks-in-series with backflow model was adopted to interpret the response data, which showed an excellent agreement between the prediction and experimental data. It also indicated that the number of stages N was 8, while the backmixing coefficient k varied between 1.320 and 4.218. Most of the variances of the predicted model were within ＋18% of their corresponding experimental values.

关 键 词：沸腾床 返混 固含率 停留时间分布 带回流的多釜串联模型 数值模拟 实验验证 

分 类 号：TQ021.1[化学工程]