Recently, the 3.4 million t/a disproportionation unit of CNOOC Ningbo Daxie Petrochemical Co., Ltd., designed and completed by the company, was successfully started for one time.

This unit adopts the S-TDT ^ TM toluene disproportionation and alkyl transfer technology of Sinopec Shanghai Research Institute of Petrochemical Industry, which is the largest disproportionation unit designed with domestic technology at present.In order to further reduce the energy consumption of the unit, the heating furnace adopts an efficient flue gas waste heat recovery system, and the overall thermal efficiency reaches 95%;The heavy aromatics tower of the conventional disproportionation unit is canceled, and the separation function is set in the xylene tower of PX unit, so that the xylene tower can achieve "one tower and three energy".In addition, the newly created re contact process of disproportionated tail hydrogen greatly recovers benzene and other aromatic compounds in the disproportionated tail hydrogen, which makes the tail hydrogen purified, thus further prolonging the operation cycle of PSA unit adsorbent.

In the process of design and construction, the company's designers took advantage of their rich experience in large-scale engineering design, actively cooperated with the owner through various ways such as overall planning, simulation calculation, technical review, etc., worked overtime, worked hard, solved a number of engineering and technical problems, constantly optimized the design scheme, and overcame the impact of the epidemic in the critical period of the project to ensure the project progress.Finally, with the close cooperation and joint efforts of all parties, the first time start-up of the device was successfully realized.