As of July, the key economic indicator of Mingsheng Biological (Diene) ethylene plant-the cumulative diene yield reached 48.81%, an increase of 0.65 percentage points year-on-year, a record high. Since the beginning of this year, the cracking workshop of the chemical division has closely focused on the annual goal of "guaranteeing advanced technology and economic indicators". Aiming at the shortcomings of 2018 diene yields in the industry, it has refined measures, wall chart operations, mobilized resources, and deepened Equipment benchmarking work, focusing on key indicators.

    Under the opportunity of the company's establishment of a cracking raw material research team, the cracking workshop makes full use of company resources to track the impact of cracking raw materials on yield in real time. When the yield drops significantly, it promptly proposes to the company to coordinate to improve the quality of raw materials. At the beginning of June this year, the quality of naphtha dropped significantly. The content of n-alkanes in the raw materials dropped from the normal 37.5% to 35.2%, and the diene yield dropped by about 0.9%. The workshop promptly fed back the information to the raw material research team. It only took three days to restore the quality of the raw materials to a normal level, effectively increasing the diene yield. At the same time, they used information resources and external resources such as Beihua Institute to optimize the cracking depth of the cracking furnace. Through SPYRO offline measurement and simulation, the optimal cracking depth and the results of the cracking furnace depth calibration of Beihua Institute were comprehensively summarized and guided. The team carried out the optimization of the operation of the cracking furnace, so that the cracking furnace was always produced according to the principle of the highest diene yield.

    Work hard on running damage to reduce diene loss and abnormal emissions. In order to avoid abnormal emissions, the cracking workshop technicians carried out internal leakage inspections on the 501 flare gas discharge points of the two sets of equipment to confirm that there was no internal leakage in the flare gas emissions. By optimizing the rotation speed of C-400 of No. 1 unit, it is ensured that C-400 is in the best condition. At the same time, in view of the insufficient processing capacity of C-400, under the coordination of relevant departments, part of the tail gas is effectively recovered through the auxiliary recovery of hydrogenation flare recovery compressor. After the components are returned to the pyrolysis system, the inline flare is avoided. In view of the high temperature of circulating water in summer, the ternary refrigerant ratio was optimized to ensure that the top temperature of the demethanizer of No. 2 unit was below -130°C, effectively reducing the ethylene loss of high-pressure methane and medium-pressure methane of No. 2 unit.

    (Sujie, Diene)