Plant InformationLocation:Dushanzi, China Order date:November 2010Completion:October 2011PetroChina Company Limited PetroChina Dushanzi Petrochemicals Polyethylene Plant System MigrationExecutive SummaryPetroChina Company Limited is China’s largest oil and gas producer and distributor, and plays a dominant role in the country’s oil and gas industry. Dushanzi Petrochemicals, a primary subsidiary of PetroChina, operates China’s largest refinery and petrochemical complex. Operational since 2009, it can process 10 million tons of crude oil and produce 1.2 million tons of ethylene per year as well as a range of fuels and other refinery products. In 2007, Yokoshin Software Engineering (WuXi) Co., Ltd., a Yokogawa subsidiary, successfully installed the distributed control systems (DCS) for this megasize complex.Dushanzi Petrochemicals also has refinery, polyethylene, utility, and other facilities at this complex that date back to the 1990s. Some of these relied on older control systems that were experiencing steadily rising failure rates and issues with the availability of spare parts. In consideration of Yokoshin Software Engineering’s success in implementing the systems for the refinery & petrochemical complex megaproject and Yokogawa’s rich system migration experience, Dushanzi Petrochemicals awarded Yokogawa a contract in November 2010 that included the revamp of the legacy Honeywell TDC3000 DCS at the complex’s polyethylene plant. This was successfully completed in October 2011 after a 50-day shutdown period and site acceptance testing (SAT). With the conclusion of the system migration work at the Dushanzi complex, most of its DCS systems are now from Yokogawa, significantly reducing its maintenance costs.About This ProjectThe plant’s TDC3000 system had eight DCS controllers, one safety controller, ten HMI/ENG stations, one application module, and one history module. With Triconex responsible for upgrading their legacy safety system, the scope of Yokogawa’s work was limited to the replacement of the TDC3000 system with a CENTUM DCS. There was no manufacturing execution system (MES) at the plant.Based on documents about the polyethylene production process (a BP gas-phase technology) and discussions with the customer’s engineers, Yokogawa understood it would be a demanding project, with many complex sequence controls, calculations, interlocks, and loops in the existing DCS.A typical TDC3000 system layoutThe Challenges and the SolutionsThroughout the revamp, which included the challenging creation of function design specifications (FDS) as well as factory acceptance testing (FAT) and SAT, Yokogawa took a team approach and worked closely with the customer. With the strong support of Dushanzi’s management and employees, this work was completed on time.Chemical (Base Chemical, Fertilizer, Petrochemical)29Success Story Collection



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