1Assistant Professor, Mechanical Engineering Department, Sharif University of Technology, 1458889694, Tehran, Iran
2Professor, Mechanical Engineering Department, Sharif University of Technology, 1458889694, Tehran, Iran
3Assistant Professor, Mechanical Engineering Department, Faculty of Engineering, University of Zanjan, 4537138791, Zanjan, Iran
4Head of Research and Technology Department, South Pars Gas Complex (SPGC), Asalouyeh, 75391/311, Bushehr, Iran
5Process and Operation Unit, South Pars Gas Complex (SPGC), Asalouyeh, 75391/311, Bushehr, Iran
چکیده
The regeneration tower in the amine cycle of a gas treatment unit and its inlet pipe containing rich amine have visible abnormal vibrations. Excessive vibrations can lead to fatigue and then, economic losses with serious damages and injuries. Therefore, it is so important to find the root cause of the vibrations and fix it. This article focuses on identifying the cause of the vibrations of the regeneration tower and provides a practical solution to prevent possible failures. In this regard, all documentations including technical information, maintenance records, and operating conditions are examined. Then, the vibration data are collected in different locations on the tower and its pipe, assessed based on the relevant standards and guidelines, and compared with vibrational behavior of a similar refinery unit. Furthermore, the impact hammer modal testing technique is implemented to find the natural frequencies of the regeneration tower. The root cause of vibrations is identified as the fluid-structure interaction and resonance using the fishbone diagram. The vibrations of two refinery units are detected the same with a difference of less than 15%. The design of two viscoelastic dampers at two high-amplitude locations is proposed as a practical strategy to reduce vibrations.
Abnormal Vibrations of a Regeneration Tower in Amine Gas Treatment Unit and Applicable Recommendation to Reduce it
Authors
Abstract
The regeneration tower in the amine cycle of a gas treatment unit and its inlet pipe containing rich amine have visible abnormal vibrations. Excessive vibrations can lead to fatigue and then, economic losses with serious damages and injuries. Therefore, it is so important to find the root cause of the vibrations and fix it. This article focuses on identifying the cause of the vibrations of the regeneration tower and provides a practical solution to prevent possible failures. In this regard, all documentations including technical information, maintenance records, and operating conditions are examined. Then, the vibration data are collected in different locations on the tower and its pipe, assessed based on the relevant standards and guidelines, and compared with vibrational behavior of a similar refinery unit. Furthermore, the impact hammer modal testing technique is implemented to find the natural frequencies of the regeneration tower. The root cause of vibrations is identified as the fluid-structure interaction and resonance using the fishbone diagram. The vibrations of two refinery units are detected the same with a difference of less than 15%. The design of two viscoelastic dampers at two high-amplitude locations is proposed as a practical strategy to reduce vibrations.
آشنایی با اصول فرآورش گاز با آمین. آموزش فنی و تخصصی شرکت ملی گاز ایران، آموزش و تجهیز نیروی انسانی، آموزش فنی و تخصصی، .1388
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