摘要
分子蒸馏作为一种特殊的液-液分离技术,能有效分离高沸点、热敏性物料,已成为乳酸工业生产主要采用的分离纯化技术.针对规模化的乳酸分子蒸馏纯化装置运行过程难以保持高真空以及收率低的难题,优化装置的真空机组,采用多泵联用的方式抽真空,提高设备运行过程中的真空度.通过对比试验,选用水环真空泵、罗茨真空泵和蒸汽真空泵三泵联用抽真空,1.25 t/h乳酸分子蒸馏纯化装置的负载真空度达到10 Pa.试验优化了分子蒸馏器蒸馏乳酸过程中冷凝温度、蒸发温度和刮膜转子转速等工艺技术参数,结果表明:当分子蒸馏器的冷凝温度30℃,蒸发温度55~60℃,刮膜器转子转速125~135 r/min时,能进一步提高蒸馏效果和收率.
As a special liquid-liquid separation technology,molecular distillation can separate high boiling point and heat sensitive materials effectively,which has become the main separation and purification technology used in lactic acid industrial production.In order to solve the problem which is difficult to maintain high vacuum and low yield in the operation of purification unit of molecular distillation,we optimize the vacuum unit of the device,and choose the method of multi-pump combination to improve vacuum.Through the comparative test,the water ring vacuum pump,the vacuum pump and the steam vacuum pump were shared to improve vacuum,and the load vacuum degree of the 1.25 t/h lactic acid molecular distillation purification device reached 10 Pa.The condensation temperature,evaporation temperature and rotor speed of film scraper were optimized in the process of lactic acid distillation with molecular distillation.The results show that we can achieve better distillation effect and yield in the condensation temperature of 30℃,evaporation temperature of 55-60℃and rotor speed of film scraper 125-135 r/min.
作者
崔洋
顾永华
王新
赵南
CUI Yang;GU Yonghua;WANG Xin;ZHAO Nan(Tianjin University,Tianjin 300072,China;Henan Jindan Lactic Acid Technology Co.Ltd.,Dancheng 477150,Henan China)
出处
《河南科学》
2022年第6期886-891,共6页
Henan Science
关键词
乳酸
分子蒸馏
分离纯化
真空度
lactic acid
molecular distillation
separation and purification
vacuum
