Abstract: A novel zoning catalytic cracking (ZCC), which processed vacuum gas oil (VGO) and vacuum residue (VR) in different zones under respective optimal conditions to avoid competitive adsorption effect, was proposed. Aiming at comparing routine fluid catalytic cracking (FCC) with ZCC, vaporization of feedstock was predicted with the UNIFAC model. Vaporization of feedstock was higher than 70% (mass) in both ZCC and FCC under investigated conditions. Higher oil-catalyst-mixing temperature, less atomized steam and lower VR blending ratio were beneficial to feedstock vaporization. Vaporization of feedstock decreased by 5.44%－7.53%(mass) when VR blending ratio increased from 30%(mass) to 50%(mass). When VR blending ratio was lower than 50%(mass), vaporization of separate feedstocks in ZCC was lower than that of blending feedstock in routine FCC. When VR blending ratio reached 50%(mass), separate feeding used in ZCC was more beneficial to vaporization of feedstock. That was the result of the influence of dispersion effect of VGO on VR and competitive vaporization between VGO and VR.

Key words: petroleum, prediction, vaporization, fluid catalytic cracking, UNIFAC model

摘要： 以不同减压馏分油（VGO）/减压渣油（VR）混合比例的重油为研究对象，采用基团贡献模型（UNIFAC）预测了常规催化裂化工艺（FCC）与分区催化裂化工艺（ZCC）中原料的汽化率。在所考察的催化裂化油剂混合条件下，原料的汽化率均大于70%（质量分数）。高油剂混合温度使饱和蒸气压升高，而大雾化水蒸气量有利于降低油气分压使泡露点温度降低，均使原料汽化率升高。VR掺炼比例对原料汽化率影响很大，当掺炼比例从30%（质量分数）提高至50%（质量分数）时，原料汽化率降低5.44%～7.53%（质量分数）。当VR掺炼比例较低（<50%）时，常规FCC工艺比ZCC工艺的原料汽化率高，当VR掺炼比例达到50%时，ZCC工艺的分开进料方式更有利于原料的汽化。这取决于VGO对VR的分散作用和VGO与VR的竞争汽化造成的影响。

关键词: 石油, 预测, 汽化, 催化裂化, UNIFAC模型