Objective The aim is to test the feasibility of using a DPC catalyst to directly conduct catalytic cracking of inferior vacuum residue in industrial units and to explore the impact of blending a certain proportion of inferior vacuum residue on product structure, mainly low-carbon olefin production.

Methods The industrial test was carried out by using a 1.2 Mt/a catalytic cracking unit. The study investigated changes in process operations and product structure through adjustments in DPC catalyst inventory proportion and raw material slag blending ratios.

Results The industrial practice of using a DPC catalyst to produce olefins from vacuum residue directly showed that when the DPC catalyst inventory proportion reached 26.5%. The blending proportion of vacuum residue in the feed was increased to 15.25%, and the ethylene volume fraction in the catalytic dry gas reached 16.57%, an increase of 2.46 percentage points compared to the blank calibration value. The yields of propylene and triene(ethylene, propylene and 1,3-butadiene) in liquefied gas reached 7.35% and 8.38%, respectively, which increased by 0.67 percentage points and 0.83 percentage points compared with the blank calibration value, monthly efficiency increase could reach 19.639 2 million yuan.

Conclusions The DPC catalyst is capable of facilitating the directly catalytic cracking of inferior vacuum residue, offering a streamlined processing flow and significant economic benefits. It can provide new ideas for enterprises to reduce costs, increase efficiency, save energy and reduce carbon.