Process method for removing water from diesel or jet fuel by using compound function vacuum tower

The invention relates to a process method for removing water frrrom diesel or jet fuel by using a vacuum tower. The vacuum tower is divided into an upper part and a lower part, diesel or jet fuel with temperature between 100 DEG C and 300 DEG C enters the lower part of the vacuum tower, and is subjected to balanced flash evaporation under an absolute pressure of 0KPa to 90KPa; water in an oil product and partial oil product are simultaneously gasified, and then enter the upper part of the vacuum tower to be condensed and subjected to oil-water separation; separated water is discharged out of the tower, separated oil is returned to the bottom-lower part of the vacuum tower, and the separated oil and un-gasified oil become qualified water-containing products and discharged out of the tower. According to the invention, the problem that the diesel or jet fuel contains water is solved, and especially, in a diesel hydrogenation unit and a jet fuel refining device of an oil refinery, by adopting the process method, the problem of unqualified mass caused by water containing is effectively solved. Compared with a reboiler furnace fractionation process adopted in the diesel hydrogenation unit and the jet fuel refining device, the process method remarkably has the characteristics of convenience for implementation, less occupation area, low energy consumption and low investment.