Glycol Dehydration Offshore Module

ETI supplied a high pressure glycol dehydration and regeneration system complete with a high pressure still and electrically heated reboiler. The purpose of the dehydration system was to prepare the gas for re-injection (reuse for pressure maintenance and the avoidance of flaring) in an offshore application. The off gas from the still was cooled through a water cooled exchanger and after separating the fluids in a KO drum. The vapors were routed to the first stage of the re-injection gas compressor. The Glycol dehydration and regeneration system was to be placed on a new platform offshore.



The overall dimensions of the glycol regeneration system was 21’W x 50’L x 41’H, triple deck platform, with a dry weight of 289,650 lbs. The contactor was constructed to ASME Section VIII Div. 2 Code to reduce the platform deck loading. The dimensions of the contactor were 84” ID x 28’ S/S x 1395 psig with 14 ft of structured packing with a dry weight of 115,000 lbs. The contactor was to be located on the main platform, adjacent to the triple deck regen skid. The contactor was to process 325 MMscfd operating at 1255 psig and 100°-120°F, dehydrating the gas to 3.5 lb H2O/MMscf using 42.8 gpm of 99.5% lean TEG, having used 2.23 scf/gallon of TEG stripping gas in the Stahl column. The triple deck platform was shipped by barge via the McClellan-Kerr and the Intercoastal waterway to the port of Houston for continuing ocean shipment to Angola.

The platform was complete with high intensity lighting and designed for fully automated operation. The regen skid was designed to operate from 5-15 psi reboiler pressure to utilize the higher pressure of regeneration to be routed to the re-injection gas compressor.