Situation: Client’s Oxidation Overhead Condenser suffered tube leaks attributed to fretting and tube wear at the OD of the tubes. Prior analyses indicated that vibration of shell side baffles was the root cause of this tube wear.
The unique design of the condenser: A large vertical exchanger that condenser acetic acid in the tubes utilizing BFW from an elevated Steam Drum that feeds a thermosyphon loop, generating 60 psig steam on the shell side, in an 11 pass, single crossflow baffle arrangement, presented a number of modeling and mechanical challenges
Action: The Becht team modeled and developed several exchanger baffle designs before settling on a rod baffle design. In addition, the team developed a liquid belt to properly distribute the flow of BFW around the circumference of the bundle at the inlet (bottom) tube sheet.
Results: Several consultants had been engaged earlier to resolve this issue with limited success. The Becht team utilized a multidiscipline Process and Mechanical team utilizing advanced modeling tools including HTRI, CFD, and COMPRESS to develop a complete solution to the client’s issue.Contact