Deep-cut Vacuum Distillation Of Atmospheric And Vacuum Distillation Unit

The main function of fuel-type vacuum column is to provide material for catalytic cracking or hydrocracking. In order to enhance economy benefit, the pull-out rate of vacuum distillation equipment should be heightened by all means on condition that feed-in oil can avoid being decomposed. The key factor is less pressure drop of the whole column and higher vacuum at column top. The new process of direct-contact heat transfer was applied in this paper. At the same time, the whole column process simulation and design were studied based on the properties and ASTM D86 datum of Huabei atmospheric residue. The results showedthat the pull-out rate of the new process was greatly heightened because it adopted many new technologies including applying hollow column direct-contact heat transfer, high vacuum gas-oil (HVGO) condensation in successive two-stage column sect, light vacuum gas-oil (LVGO) making diesel oil, dry vacuum distillation and slop oil being recycled back to the vacuum furnace inlet. In search of the basis that direct-contact heat transfer is applied to fuel-type vacuum column, spraying experiment and heat transfer experiment of spray nozzle distributor were studied in the paper. To overcome the shortcoming that spray nozzle distributor leads to serious liquid entrainment problems, the author designed a new kind of distributor named dripping distributor, and did heat transfer experiment of the dripping distributor. The results showed that the application of hollow column direct-contact heat transfer to fuel-type vacuum column was effective. It not only economized packings but also greatly reduced the pressure drop of the whole column.