The invention belongs to the technical field of 
petroleum processing, and relates to a flash 
distillation washing method for the atmospheric and 
vacuum distillation of 
crude oil. The method comprises the following steps: carrying out heat exchange on 
petroleum dehydrated 
crude oil, so that light components are vaporized, then feeding oil gas into a flash 
distillation washing 
tower through a pipeline to carry out flash 
distillation, so that light and heavy components of the oil gas are separated; taking flash distillated oil gas carrying the heavy components and part of second side 
cut distillate oil from an atmospheric 
tower as washing oil, carrying out reverse contact on the washing oil on packing in the flash distillation washing 
tower to carry out washing and 
mass transfer separation, so that flash top oil gas escapes from the top of the flash distillation washing tower and then enters an upper gas-
phase space of a second side 
cut oil extraction plate of the atmospheric tower, and heavy-component washing oil is extracted from an oil collecting tank of the flash distillation washing tower and then automatically flows to places above and below a third side 
cut extraction plate of the atmospheric tower; after un-vaporized flash bottom oil is pumped out by using a pump from the bottom of the flash washing tower, carrying out heat exchange on the un-vaporized flash bottom oil and heating the un-vaporized flash bottom oil by using an atmospheric furnace, and then feeding the un-vaporized flash bottom oil into the atmospheric tower so as to separate out atmospheric overhead oil, atmospheric 
lateral line distillate oil and atmospheric heavy oil through distillation. The method disclosed by the invention is reasonable in process 
route, good in adaptability, good in 
energy conservation, low in investment, convenient to control, and friendly in production environment.