Abstract: Disclosed is a process for vacuum distillation of a hydrocarbon stream comprising i) passing a hydrocarbon stream into a preflash vessel maintained under conditions to separate the hydrocarbon stream into a preflash liquid and a preflash vapor, ii) passing the preflash liquid into a vacuum furnace maintained under conditions to heat and partly vaporize the preflash liquid, iii) passing the heated furnace effluent into a zone located in the lower part of a vacuum distillation column maintained under fractionating conditions, and iv) passing the preflash vapor into the vacuum distillation column into a further zone located in the lower part of the vacuum distillation column.

Abstract: The invention relates to a process for vacuum distillation of a hydrocarbon stream comprising i) passing a hydrocarbon stream into a preflash vessel maintained under conditions to separate the hydrocarbon stream into a preflash liquid and a preflash vapor, ii) passing the preflash liquid into a vacuum furnace maintained under conditions to heat and partly vaporize the preflash liquid, iii) passing the heated furnace effluent into a zone located in the lower part of a vacuum distillation column maintained under fractionating conditions, and iv) passing the preflash vapor into the vacuum distillation column into a further zone located in the lower part of the vacuum distillation column. The invention also relates to a high vacuum unit (HVU) configured to perform the vacuum distillation process.