Abstract: Enhancing the deep processing of naphthenic-base heavy oil has extremely important industrial and economic significance. Based on the Qinhuangdao naphthenic-base heavy oil, a novel heavy oil to petrochemicals process integrated with light cycle oil (LCO) deep hydrotreating and two-stage-riser for maximizing propylene (DHTMP) is carried out, simulated, and optimized. Based on the pilot test data, the DHTMP process for the production of low-carbon olefins and BTX was simulated and optimized, and the optimized operating parameters were obtained. Using the optimized operating parameters, i.e. the outlet temperatures of the first and second riser reactors are 520 ℃ and 540 ℃ respectively, and the total yield of gasoline and LPG obtained by DHTMP process exceeds 83%. Furthermore, the DHTMP process exhibits favorable performances from the economic level. The DHTMP process has better net present value of 2.16×10⁹ CNY, and internal rate of return of 21.56% for a unit with capacity of 2.0 Mt/a. The results of carbon emission analysis show that the DHTMP process emits 78.08 tons of carbon dioxide per million yuan of total output value.

Key words: naphthenic-base vacuum gas oil, deep catalytic cracking, deep hydrogenation, process integration, process simulation, optimal design