The invention discloses a vacuum flash
tower based on vacuum deep
distillation and a
crude oil processing system and method, and belongs to the technical field of
petroleum refining. According to the method, vacuum residue at the bottom of a vacuum
tower is subjected to secondary
flash evaporation by additionally arranging a vacuum
flash evaporation tower, and light components (mainly
wax oil) in the vacuum residue are further recovered. The vacuum flash tower adopts a combined design of an upper packed tower section and a lower plate tower section, the packed tower section is used for absorbing light components, and the plate tower section is used for prolonging the
residence time of
residual oil. And part of vacuum third-line
wax oil extracted from the side line of the vacuum tower enters the top of the flash tower as an absorbent, absorbs
flash light components and then is refined back to the vacuum tower, so that the product quality is ensured. The vacuum flash tower and the vacuum tower share a vacuum
system, and the tower pressure is maintained at 4 kPa. According to the method, the vacuum residue extraction rate is remarkably increased, vacuum equipment does not need to be additionally arranged, the problem that light-component
metal and
residual carbon exceed the standard in a traditional process is solved, and
economic benefits are remarkable. The method is suitable for
heavy crude oil processing and has the advantages of low equipment investment, simple operation and the like.