Troubleshoot and solve a gas treater downcomer unsealing problem: Part 2

H. Z. Kister, Fluor, Aliso Viejo, California; and N. M. Mohamed, WorleyParsons Engineering Pty Ltd., Abu Dhabi, UAE The ADGAS Integrated Gas Development (IGD) fuel gas treatment (FGT) system is a methyldiethanolamine (MDEA) absorber-regenerator system designed to supply 25 MMscfd of sweet fuel gas (having less than 20 ppm of H2S) for the IGD turbines and the flare purge and pilots. The FGT system was designed by an engineering contractor from Japan, and the tower internals were provided by a major tray supplier. At plant rates above 10 MMscfd–12 MMscfd, the absorber column, which contained moving valve trays, became very unstable and flooded, resulting in a sudden liquid carryover that led