不同折板絮凝器对薄荷水提液的絮凝效果研究与比较

为了优化折板絮凝器结构及提升折板絮凝器对中药液的絮凝效果，利用FLUENT软件对同波/对波折板絮凝器的内部流场进行了模拟，分析了两种折板絮凝器内的涡旋分布及涡量。以薄荷水提液为研究对象，壳聚糖为絮凝剂，采用不同折板絮凝器对薄荷水提液进行絮凝处理，以薄荷水提液澄清层高度、絮体沉降速度、总黄酮保留率、絮凝率、药液吸光度及絮体形态为指标，考察了两种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，同波折板絮凝器流场内以单侧涡旋为主，对波折板絮凝器内在折板两侧均产生涡旋，相同进液流速下，同波折板絮凝器产生的涡量小于对波折板絮凝器。随进液流速增加，同波/对波折板絮凝器对薄荷水提液的絮凝效果均呈先升高后降低的趋势，同波折板絮凝器最佳进液流速为0.068 m/s，药液总黄酮保留率为91.2%，絮凝率为85.3%；对波折板絮凝器最佳进液流速为0.051 m/s，药液总黄酮保留率为91.8%，絮凝率为85.4%。

Comparison and study on the flocculation effect of peppermint water-extraction solution by different folded-plate flocculators

As a part of the excellent culture of the Chinese nation, traditional Chinese medicine have been favored by more and more people in recent years due to its high safety and low side effects. At present, most of the researches on impurity removal of traditional Chinese medicine by flocculation were based on the flocculation operating conditions, such as flocculation temperature, pH value of the traditional Chinese medicine solution and different flocculants. In order to optimize the structure of the folded-plate flocculator and enhance the flocculation effect of the Chinese medicine liquid. Vortex distribution and vorticity in the flow field of the same wave folded-plate flocculator and the opposite wave folded-plate flocculator were simulated and analyzed by FLUENT. Taking the peppermint water-extraction solution as the research object, using chitosan as a flocculant, flocculating the peppermint water-extraction solution by different folded-plate flocculators, let clear layer height, sedimentation velocity, total flavonoid retention rate, flocculation rate, absorbance and fractal dimension of flocs index, the influence of different inlet flow rates on flocculation for the effect of flocculant by different folded-plate flocculators were discussed. Results showed that the vortex positions of the same wave folded-plate flocculator were respectively unilateral vortex, and the vortex position of the opposite wave folded-plate was distributed on the two sides of the folded plate, under the same inlet flow rate, the vorticity generated by the same wave folded-plate flocculator was smaller than that of the opposite wave folded-plate flocculator. The flocculation effect of the same wave and the opposite wave folded-plate flocculator on the mint water extract showed a trend of first increasing and then decreasing, the optimal flocculation inlet flow rate of the same wave folded-plate flocculator was 0.068 m/s, the total flavonoid retention rate of the peppermint water-extraction solution was 91.2% , the flocculation rate was 85.3%, the optimal flocculation inlet flow rate of the opposite wave folded-plate flocculator was 0.051 m/s, the total flavonoid retention rate of the peppermint water-extraction solution was 91.8%, the flocculation rate was 85.4%.