混合油负压蒸发工艺探讨

Vacuum evaporation technology of miscella

浸出毛油的品质随着加热温度的升高和时间的延长显著降低,混合油负压蒸发工艺是使一蒸、二蒸、汽提在负压状态下操作,同时,利用蒸脱机的二次蒸汽作为一蒸的热量来源。一方面在负压状态下可以减少油脂与空气中氧分子的接触;另一方面可以降低混合油中溶剂的沸点,以达到降低蒸发温度的目的。可以节约能源、节省钢材、提高毛油质量。在负压蒸发工艺设计中要注意合理配备冷凝面积,降低冷却循环水的温度,防止蒸脱机气相产生正压,控制蒸脱机二次蒸汽量,合理操作第二蒸发器,使用湿式粕末捕集器,加大第一蒸发器面积,列管适当加长加大,并选用不锈钢材质,选择蒸汽喷射泵,合理选择真空度,搞好余热利用和尾气回收。

The quality of crude oil with solvent extraction can be significantly decreased with the increase of heating temperature and the prolonging of heating time.Miscella vacuum evaporation technology is that the first evaporator,the second evaporator and stripping column are operated in vacuum,and the second steam is as the heating soruce of first evaporator.The vacuum evaporation technology has some advantage,such as reducing the contact of oil with oxygen in air,reducing the solvent boiling point of miscella and the evaporation temperature,saving energy,saving steel materials,improving the quality of crude oil and so on.In the design of vacuum evaporation,some points should be paid attention to,such as allocating condensation area,decreasing the temperature of cooling water,preventing desolventizer-toaster from positive pressure,reasonably operating the second evaporator,using wet fines catcher,enlarging the area of first evaporator,selecting stainless steel material and steam jet pump,reasonably choosing the vacuum degree,making good use of used heat and etc.