规整填料塔萃取回收母液中咖啡因的应用研究

Application of a structured packing tower in extraction of caffeine in mother liquid

为降低生产能耗和便于生产操作,采用规整填料塔对某咖啡因生产企业萃取工序进行设备改造,其中氯仿为连续相。中试试验中,在相同工况条件下,对往复筛板萃取塔和规整填料塔的处理能力进行了比较,系统地考察了填料萃取塔(塔径600 mm,填料实际有效高度7 m)对不同质量分数、不同类型的咖啡因母液的处理能力和最佳流比。中试结果表明,规整填料萃取塔的处理能力比往复筛板萃取塔大,萃取塔在S/F为0.8,甲化母液最大处理量为5 m3/h,咖啡因的萃取率为99.8%,残液中咖啡因质量分数和氯仿残留满足工业生产的要求。

In order to reduce energy consumption and facilitate the operation,a structured packing tower is used to extract caffeine in mother liquid with chloroform as continuous phase and mother liquid as dispersed phase.In the industrial-scale tests,the capacity of the structured packing tower is compared with the reciprocating plate column （RPC） at the same condition.The effect of the column with 600 mm I.D.and 7 m packing height on the adaptability of mother liquid with different feed rates,concentrations and flow ratios is studied.The results show that the structured packing tower has higher capacity than the reciprocating plate column.The most suitable flow ratio（S/F） is 0.8.For 5 m3/h caffeine mother liquid,the extraction of caffeine can reach 99.8％,which is the maximum throughput of the tower in the caffeine extraction process.The concentrations of caffeine and the chloroform residue in the raffinate both meet the requirement of the industrial production.It has a certain practical significance for the further industrial scale of caffeine extraction and the widespread application of the structured packing extraction column.