Method and device for preparing caprolactam through cyclohexanone oxime rearrangement reaction

The invention relates to a method and a device for preparing caprolactam through a cyclohexanone oxime rearrangement reaction. The device comprises a three liquid phase mixer, a hypergravity reactor, and a subsequent rearrangement reactor. The preparation process comprises the steps that: cyclohexanone oxime, a heat extraction solvent, and a amidation solution are mixed in the three liquid phase mixer, wherein a mixing temperature is 40-80 DEG C, a volume ratio of the heat extraction solvent to cyclohexanone oxime is 5-20:1, and an acid-oxime molar ratio is 0.6-2.0:1. The mixed liquid is mixed and is subjected to a reaction in the hypergravity reactor; a mixed material left the hypergravity reactor is subjected to a further rearrangement reaction in the subsequent rearrangement reactor, wherein a reaction temperature is 60-120 DEG C and a reaction pressure is 0-0.3MPa; and a reaction product is subjected to processes of crystallization, neutralization, extraction, and refining, such that caprolactam is prepared. According to the invention, the three liquid phase mixer, the hypergravity reactor, and the subsequent rearrangement reactor are combined, such that mixing and reaction processes are reinforced, and cyclohexanone oxime conversion rate and caprolactam selectivity are improved.