Technical Data of Rising Film Fvaporator & Stripping Tower,Technical Data of Rising Film Evaporator in Solvent Evaporation System,Technical Data of Stripping Tower in Solvent Evaporation System
Vacuum evaporation system is used for removing the solvent from the miscella from the oil extractor to obtain the crude extracted oil. The main equipment includes the first rising film evaporator, the second rising film evaporator, and disk stripping column.
Utilizing the difference of boiling point between the oil and solvent, the evaporator heats the miscella so that most of the solvent vaporizes and separates with the oil.
Then utilizing the difference of volatility between the oil and solvent, the stripping tower adopts steam distillation method to remove the residual solvent in the miscella.
After evaporation and steam stripping, crude extracted oil of low residual solvent content is obtained. The solvent vapor enters the condenser to be recycled to use. The solvent evaporation system adopts negative pressure evaporation technology, using the secondary steam from the desolventizer toaster as the heat source of the first evaporator and using the steam jet pump to vacuumize the system to make it works under negative pressure, having low evaporating temperature and good oil quality, saving steam and solvent consumption.
Operational Process of Solvent Evaporation System
miscella pretreatment→miscella tank→the first evaporator→the second evaporator→stripping tower→crude extracted oil
1.The thick miscella from the oil extractor is pumped into the hydrocyclone to remove the fines by centrifugal force.
2.The miscella is pumped into the miscella tank which has settling separation function.
3.Then the miscella is pumped into the tube pass of the first rising film evaporator. The shell pass adopts the secondary steam from the desolventizer toaster and the exhaust steam from the steam jet pump as the heat source to evaporate the solvent in the misella.The solvent vapor and miscella enter the vapor & miscella separator.
4.The miscella is pumped into the heat exchanger to be heated by the high-temperature crude oil from the stripping tower.
5.The miscella is pumped into the second rising film evaporator. The shell pass uses indirect steam as the heat source to evaporate the solvent.The solvent vapor and miscella enter the vapor & miscella separator. The first evaporator and the second evaporator works under the same negative pressure.
6.The miscella from the second evaporator is pumped into the disk stripping column from the top and fills up the overflow tray of the first group of the disk. The miscella flowing out forms a thin film on the cone-shaped disk and flows down.The annular tray holds the miscella which then flows to the overflow tray of the next group of the disk. With the flowing down of the miscella, the direct steam rises up from the bottom and countercurrent contact with the miscella to remove the residual solvent.
7.The crude oil is pumped out from the bottom of the stripping tower and then pumped into the heat exchanger for heat transfer with the miscella from the first evaporator. After cooled by crude oil cooler, the oil is pumped into the crude oil tank and later pumped into the refining workshop.
Introduction of vacuum evaporation system