Crude oil deep vacuum distillation process and system

Abstract

The invention discloses a crude oil deep vacuum distillation process and a system, a first-stage flash column is arranged between an atmospheric distillation column and a vacuum furnace, a vacuum transfer line from the outlet of the vacuum furnace to a vacuum distillation column is eliminated, a second-stage flash column is arranged between the vacuum furnace and the vacuum distillation column, the heavy oil on the bottom of the atmospheric distillation column, i.e. bottom oil, is mixed with cyclic vacuum residue and then the mixture enters into the first-stage flash column; the bottom oil of the first-stage flash column enters into the second-stage flash column with special structure after being heated by the vacuum furnace, the bottom oil of the second-stage flash column is introduced into the flash section of the vacuum distillation column for vacuum distillation. Gas phase producing is performed on the gas phase region upon at lease one liquid phase side line of the vacuum distillation column, and a vacuum pumping system is connected. Compared with the prior art, with the invention, on the one hand, the yield of vacuum residue can be reduced, and economic benefit of the device can be improved; and on the other hand, the load of the vacuum furnace and the vacuum distillation column can be reduced, the equipment investment can be saved, and the energy consumption of the device can be reduced.

Description

technical field [0001] The invention belongs to the field of petroleum refining, and in particular relates to a crude oil distillation method and system, and more specifically to a crude oil vacuum deep-drawing process method and system for improving the extraction rate. technical background [0002] Atmospheric and vacuum distillation of crude oil is the first process of petroleum refining, and it is the "leading" device of the refinery. The process is to divide crude oil into components of different distillation ranges through the principle of distillation, so as to adapt to products and downstream devices. Process requirements for raw materials. The conventional atmospheric and vacuum distillation process of crude oil mostly adopts the process of "two furnaces and three towers": crude oil enters the primary distillation tower (or flash tower) after pretreatment, and then enters the atmospheric distillation tower after being heated in the normal pressure furnace, and the b...

AI Technical Summary

Problems solved by technology

Since the oil transfer line must be more than 15m (to ensure that the gas-liquid phase has a certain stratification time, which is conducive to improving product quality and the extraction rate of the vacuum distillation tower), the large-diameter and long-distance oil-transfer line occupies a large part of the vacuum distillation unit At the same time, factors such as heat loss and pressure drop increase are not conducive to the operation of the vacuum distillation tower, and the resulting thermal stress and thermal displacement cause certain difficulties in design and installation in terms of safety.

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