异波扰流折板絮凝器对薄荷水提液的絮凝效果研究

Study on the Flocculation Effect of Peppermint Water-extraction Solution by the Opposite Folded-plate with Baffle Flow Flocculator

为了优化折板絮凝器结构以及提升折板絮凝器对薄荷水提液的絮凝效果,在普通异波折板絮凝器的基础上设计了一种异波扰流折板絮凝器。利用FLUENT对异波扰流折板絮凝器的内部流场进行模拟,分析异波扰流折板絮凝器流场内的涡旋分布,并以壳聚糖为絮凝剂,使用异波扰流折板絮凝器对薄荷水提液进行絮凝处理,以澄清层高度、絮体沉降速度、药液吸光度及絮体分形维数为指标,考察异波扰流折板絮凝器在不同进液流速下对薄荷水提液的絮凝效果。结果表明:异波扰流折板絮凝器产生的涡旋主要分布在扰流体后方以及折板两侧。随着进液流速的增加,异波扰流折板絮凝器对薄荷水提液的絮凝效果逐渐变差,当进液流速为0.041 m/s时,絮凝效果最好,絮体密实度最高。设计一种用于中药液除杂的新型折板絮凝器,为进一步优化折板絮凝器结构以及促进中药精制提供理论依据。

To optimize the structure of the folded-plate flocculator and enhance the flocculation effect of peppermint water-extraction,an opposite folded-plate with baffle flow flocculator was designed based on the ordinary opposite folded-plate flocculator.The vortex distribution in flow field of the opposite folded-plate was simulated and analyzed using FLUENT.Using chitosan as a flocculant and the opposite folded-plate,the clear layer height,sedimentation ratio,absorbance,fractal dimension of flocs index were indicated,and the influence of different inlet flow rates on flocculation was discussed.Results show that the vortex position of the opposite folded-plate with baffle flow flocculator is distributed on both sides of the folding plate and the rear of the cylinder.With the increase of the inlet flow rate,the flocculation effect of the opposite folded-plate on the peppermint water-extraction becomes gradually less effective.At inlet flow rate of 0.041 m/s,the flocculation effect was the best and the floc density was the highest.This a new type of folded-plate flocculator can be used in the field of flocculation and impurity removal of Chinese medicine liquid,and provide a theoretical basis for further optimizing the structure of folded-plate flocculator and promote the refinement of Chinese medicine.