Suspended bed residual oil hydrogenation technology is a hydrocracking process for inferior residual oil. It has the characteristics of strong raw material adaptability, simple process, flexible operation, and high conversion rate. It can process raw materials that are difficult to process with other residual oil hydrogenation technologies, such as oil sand asphalt and other heavy oil raw materials. It is a very promising residual oil hydrogenation conversion technology. In 2013, ENI's first industrial large-scale device, the 1.15 million ton/year suspended bed hydrogenation unit, was successfully put into operation. In July 2014, the domestically extended 450,000 ton/year VCC unit was successfully put into operation. According to the application of the process, many problems are still unresolved. It is expected that the next extension or KBR can solve it. When the suspended bed hydrogenation unit processes Maya residual oil, the wall phase coke generated in the reactor is the most, and the entire product is The liquid yield is also the lowest, only about 53%. Therefore, it is necessary to set up a fixed-bed hydrogenation reactor in the subsequent part for secondary treatment to increase the product yield of the residual oil raw material.