Separation of Indigo Naturalis by foam flotation technique in a continuous mode / 中草药

ABSTRACT

Objective To study the process of foam flotation in separation of Indigo Naturalis in a continuous mode and to optimize the operational conditions.Methods Taking content and rate of recovery rate of indigo as index to investigate the single factors,such as the height of collecting region,the height of froth layer,flushing water rate,delivery rate,air flow rate,and aerating velocity,to study the effect of continuous foam floatation on Indigo Naturalis,and to optimize the process conditions finally.Results The flotation performance is good when the height of collecting region is 1.5 m,the height of froth layer is 30 cm,the delivery rate is 0.1 cm/s,the flushing water rate is 0.01 cm/s,the aerating velocity is 1.5 cm/s.The recovery rate of indigo is more than 75% and indgo content is over 5.0%.Conclusion Foam flotation technique is stable and can be used to the separation of Indigo Naturalis in a continuous mode.And this study is the foundation of semi-works production of Indigo Naturalis.