Since the beginning of this year, Daqing Petrochemical Company has been adjusting the material flow in the oil refining area based on the principle of "oil when appropriate, olefin when appropriate, and aromatics when appropriate", optimizing the production of self-produced heavy ethylene feedstock, and achieving efficient operation of the oil refining area facilities. From January to July, the overall ethylene yield increased by 0.12% year-on-year, and the overall yield of ethylene and propylene increased by 0.13% year-on-year, demonstrating significant efficiency gains from the integrated layout of refining and chemical production.
Systematically optimizing the structure and enhancing raw material quality. Faced with the dual challenges of blending finished oil and supplying ethylene feedstock, Daqing Petrochemical has balanced the production demands of upstream and downstream processes, comprehensively reviewed the properties and flow of various distillate materials in the oil refining area, and determined the optimization and utilization plan. By innovatively applying precise raw material evaluation methods for accurate identification, it has designated the hydrogenation tail oil and the second cut from the 6 million tons/year atmospheric and vacuum distillation unit as high-quality ethylene feedstock. Measures such as reducing the amount of inferior raw materials and increasing the production of hydrogenation tail oil to 1,200 tons per day have been taken to gradually lower the proportion of high-aromatic components and increase the proportion of high-quality cracking feedstock, thereby enhancing the economic efficiency of ethylene feedstock from the source.
Steady and phased switching to ensure diesel production. Starting from May 7th, Daqing Petrochemical gradually reduced the feedstock volume of the first cut from the 6 million tons/year atmospheric and vacuum distillation unit in three phases from 1,200 tons per day to 500 tons per day, while supplementing the gap in ethylene feedstock from the second cut of the same unit. A one-week observation period was set up to closely monitor the operation parameters of diesel desulfurization and diesel refining units, the properties of raw materials, and key blending indicators such as diesel sulfur content and cetane number to ensure that the diesel product qualification rate remained at 100% throughout. From January to July, diesel production increased by 26,500 tons year-on-year, achieving coordinated advancement in refining and chemical production.
Comprehensive improvement in benefits, achieving integrated win-win. Daqing Petrochemical adheres to the concept of "molecular refining", fully tapping the potential of existing facilities, and making full use of different distillate resources. The overall ethylene yield of E1 and E2 units increased by 0.24% year-on-year, and the average operating cycle of the cracking furnaces in the E3 unit was extended by 8.2%. While the frequency of coke burning decreased, the steam generation efficiency increased by 12%, exploring a new path for the efficient operation of integrated refining and chemical production.