筛孔型溢流管旋流器分离性能研究

旋流器在分离过程中由于短路流的存在造成溢流跑粗现象，针对此问题提出一种筛孔型溢流管旋流器，并进行数值模拟和试验研究。结果表明：与圆柱型溢流管相比，筛孔型溢流管结构可延长颗粒在旋流器内的分离时间，使短路流重新进入外旋流进行充分分离，减少溢流跑粗现象。对比试验结果表明，与圆柱型溢流管旋流器相比较，采用筛孔型溢流管分离效率显著提高，-25 μm分级质效率由47.59%提高到58.00%，分级量效率由48.74%提高到60.08%，溢流产物更细，粗颗粒减少，溢流跑粗现象得到有效改善；随着溢流管开孔率增大，溢流产率提高，溢流和底流产品粒度均有变粗的趋势。

Study on Separation Performance of Hydrocyclone with Sieve-type Overflow Pipe

Aiming at the problem of coarse particles mixed in the overflow product caused by short-circuit flow during the hydrocyclone separation process， a hydrocyclone with a sieve-type overflow pipe is proposed， and the numerical simulation and experimental research was carried out. The simulated results show that compared with the cylindrical overflow pipe， the sieve-type overflow pipe can effectively prolong the separation time of the particles in the hydrocyclone. Therefore the short-circuit flow can re-enter the external swirl and be separated throughly， reducing the coarse particles mixed in the overflow product. The experimental results show that compared with the cylindrical overflow pipe hydrocyclone， the separation efficiency after using the sieve-type overflow pipe is significantly improved. The classification efficiency of -25μm particles increases from 47.59% to 58% by quality and from 48.74% to 60.08% by quantity. The overflow product is finer verifying that the coarse particles mixed in the overflow product is effectively improved. As the opening rate of the overflow pipe increases， the overflow yield increases， and the overflow and underflow product grain sizes tend to become thicker.