MPC REVAMP OF TWO NAPHTHA CRACKERS, LESSONS LEARNED AND RELEARNED

摘要

Braskem is the 8th largest petrochemical company in the world and the biggest producer ofrnpolymers in the Americas. The Braskem Triunfo site includes 2 Naphtha Crackers with arncombined capacity of 1250 KTA ethylene and 685 KTA propylene. AspenTech DMCplus~?rncontrollers had been built for both plants over the past 10 years, but were not fullyrnoperational.rnIn 2010 a project was initiated to review the performance of the advanced control systemsrnand improve their operability, service factor and economic impact. A further objective was tornincrease the knowledge of the site process control engineers. This paper gives an overviewrnon the project, including the basis for deciding which areas to focus on, changes made at bothrnthe regulatory and advanced control level, and the results obtained. Changes in operationalrnphilosophies which improved process stability and efficiency are discussed. Techniques andrntools used in the project are highlighted.