(99a) Vertical Thermosyphon Reboiler Operation Troubleshooting

Vertical thermosyphon reboiler stall can result in a loss of duty and/or a loss of unit capacity. The cryogenic demethanizer reboiler is susceptible to stall during transient or turndown operation, typically resulting from a relatively wide boiling range of the tower bottoms composition and a relatively small difference between the reboiler’s inlet and outlet densities. This paper will discuss methods for correctly identifying a reboiler performance problem as stall, and will examine and share field techniques for un-stalling a reboiler.