Abstract: The maximized vacuum deep-cut benefits can only be achieved when the eligible reprocessed raw material is produced. We must take atmospheric and vacuum devices with reprocessing plant as a whole to consider, and based on the nature of raw materials and quality requirements, the right operation conditions for varies system can be determined, like the reasonable vacuum cutting temperature, the stripping of atmospheric tower bottom, flow rate and outlet temperature of vacuum furnace, liquid level of washing oil sump tank, segmentation of each side cuts in vacuum tower and micro-wet stripping of vacuum tower bottom, to reduce the energy consumption of vacuum deep-cut. Besides, the atmospheric distillation can be strengthened by the addition of FCC slurry oil together with the process optimization and regulation to produce qualified distillates, so as to realize the large system optimization and maximize the benefit of the whole refinery.