Evaluation of Dehydration Unit Performance in a Gas Processing Plant in Bayelsa State

Gas dehydration is a critical processing step in the natural gas treatment chain, required to prevent hydrate formation, corrosion, and water condensation in transmission pipelines. This study evaluates the operational performance of a triethylene glycol (TEG) dehydration unit at a gas processing plant in Bayelsa State, assessing its effectiveness in achieving the specified pipeline water dewpoint requirement of minus 10 degrees Celsius at operating pressure. The research employs a process performance evaluation methodology, collecting TEG unit operational data including glycol circulation rate, regenerator temperature, lean TEG concentration, contactor operating pressure, and measured outlet dewpoints over a six-month period. The data are compared against design performance benchmarks and analysed using Aspen HYSYS simulation to identify deviations and their root causes. Key performance issues identified include insufficient lean TEG concentration caused by inadequate regenerator temperature control, excessive glycol losses through vapour carryover in the absorber, and fouled glycol heat exchangers reducing regeneration efficiency. The study quantifies the impact of these deficiencies on outlet water content exceedances and the resulting corrosion risk in the downstream export pipeline. Recommendations include regenerator temperature upgrade to achieve 99 percent lean TEG purity, installation of a glycol flash tank to reduce atmospheric glycol losses, and enhanced heat exchanger maintenance schedules. This study provides a performance improvement blueprint relevant to gas processing operations in the Niger Delta. Keywords: TEG dehydration, gas processing, water dewpoint, glycol, Bayelsa State.