多种搅拌型式下高黏黄原胶混合过程研究  

Mixing process of high-viscosity xanthan in different agitation system

作　　者：周珍[1] 谢明辉[1] 夏建业[1] 郭美锦[1] 储炬[1] 庄英萍[1] 张嗣良[1] 

机构地区：[1]华东理工大学生物反应器工程国家重点实验室,上海200237

出　　处：《化学工程》2014年第5期51-55,共5页Chemical Engineering(China)

摘　　要：黄原胶的发酵后期发酵液体系黏度增大,呈典型假塑性非牛顿流体特性,发酵液体系的混合成为提高黄原胶发酵生产水平的主要制约因素。研究黄原胶的混合特性与影响因素从而提高混合效果意义非凡,因此文中采用比色法与pH法相结合的方式研究黄原胶水溶液的混合过程。重点考察了6种桨型组合、3种黄原胶质量分数、2种通气比和4种单位体积功率。通过以上研究得出对于高黏体系,不同搅拌型式的混合效果区别很大,大桨型组合(D/T=0.9,0.95)的混合效果明显好于小桨型(D/T=0.43);对于相同直径(D/T=0.43)的组合桨,轴流桨组合的混合效果比径流桨组合好;得到混合时间与单位体积功率、表观黏度的关联式。这一结论为工业上提高黄原胶发酵产量提供了理论指导,具有一定的实际意义。In the later period of xanthan fermentation,the broth shows classical pseudoplastic rheology property, which makes mixing efficiency to be the major limitation for xanthan production. Therefore,it＇s quite valuable to understand the mixing process in xanthan broth and its influencing factors. The mixing process of xanthan solution was studied by both colorimetric and pH method. Focusing mainly on the mixing process under various operating conditions： six kinds of impeller combinations,three xanthan mass fractions,two gas flow rates and four volumetric power consumptions,it reveals that for high xanthan viscosity,different impellers show distinguished mixing capacity： the large impeller combinations（ D / T = 0. 9,0. 95） are significantly better than those of small impellers（ D/T =0. 43）. For impellers with the same diameter（ D/T = 0. 43）,axial propellers combinations are much better than those of radial propellers. Mixing time is correlated well with apparent viscosity and specific power consumption. This conclusion provides a theoretical guidance to improve the industrial xanthan fermentation,and has a practical significance.

关 键 词：比色法 pH法 高黏黄原胶体系 混合时间 

分 类 号：O629.12[理学—有机化学] TQ027[理学—化学]