水力旋流器筛分纸浆纤维过程的流场分析

Analysis of the Flow Field in Hydrocyclone for Fractionation of Pulp Fiber

旋流器的流场研究是认识其分离机理的基础。通过用柱形水力旋流器对漂白化学热磨机械浆进行筛分的实验 ,获得了分流与流场相互关系的新认识。应用纤维质量分析仪对不同浆流纤维的长度特性进行了测定 ,并计算了纤维的长度分率密度 f。基于流场的湍动性对分离有重要影响 ,提出了根据溢流量和进料量的关系 ,以及轴向速度的变化决定旋流器长度的方法 ,旋流器小锥角的角度越大 ,分离段越长 ,越有利于提高分离效率。

The research on flow field in hydrocyclones is the base of understanding their separation mechanism. After research on the fractionation of softwood BC TMP pulp fiber by a cylindrical hydrocyclones, a new knowledge of the relationship between split ratio and flow field in hydrocyclones was gained. Pulp fiber length characterization in different streams have been examined using FQA. Because the turbulence of flow has signifricant influence on separation, the auther posed the concern of feed pulp and overflow, and the change of axial velocity which determined the length of hydrocyclones. The larger direction of it, the longer of separation part, the more benefit for improving the separation efficiency.