关键词: 低生焦, 高低碳烯烃, 催化裂化工艺, 加氢重油, 脱沥青油, 反应物分子结构, 有效空间约束

Abstract:

In order to solve the problem of high coke yield caused by high conversion rate in catalytic cracking process with high reaction harshness for high yield of light olefins, the concept of optimizing the properties of catalytic cracking feedstock to form an effective spatial constraint between the feedstock molecular structure and the pore structure of catalyst is proposed. Thus, a research idea of catalytic cracking process with low coke and high light olefins yield is formed. The test results show that for the hydrogenated heavy oil that is not suitable for the production of light olefins, the integration technology of solvent deasphalting and catalytic cracking is used to remove the resin and asphaltene of hydrogenated heavy oil, and the deasphalted oil is used as the feedstock of catalytic cracking, and the coke yield is greatly reduced. For Daqing VGO with high saturated hydrocarbon content, the spatial constraint effectiveness of mesoporous MFI molecular sieve(TCC-1 catalyst) with Daqing VGO molecules is significantly better than that of macroporous Y molecular sieve(MMC-2 catalyst). The coke yield decreases by 28.9% and the olefin yield increases by 6.3 percentage points. When HVGO with higher aromatic content is used, the condensation reaction of polycyclic aromatics on mesoporous MFI molecular sieve is difficult to be effectively inhibited with the increase of polycyclic aromatics in the reactants. These research results provide a more in-depth theoretical understanding for the deep development of mesoporous molecular sieve heavy oil catalytic cracking technology with low coking, low energy consumption and high olefin products, and provide a more reliable theoretical basis for the transformation and development of oil refining technology.

Key words: low coke, high light olefins, FCC, hydrogenated heavy oil, deasphalted oil, reactant molecular structure, effective spatial constraints