GPSA Figure 20-63 · McKetta-Wehe Charts
Uses GPSA equilibrium data to predict achievable water dewpoint based on lean TEG concentration and contactor temperature. Water content calculated from McKetta-Wehe charts.
TEG dehydration process flow, GPSA design methods, McKetta-Wehe charts, glycol regeneration, and contactor sizing.
Higher TEG concentration → Lower equilibrium dewpoint → Lower water content
It calculates the equilibrium water dewpoint achievable with TEG (triethylene glycol) dehydration using GPSA Figure 20-63 equilibrium data and McKetta-Wehe water content charts.
It uses GPSA Figure 20-63 for TEG-water equilibrium data and McKetta-Wehe charts for natural gas water content calculations.
TEG dehydration uses triethylene glycol to absorb water from natural gas, lowering the water dewpoint to meet pipeline or processing specifications.
Higher TEG lean concentration achieves deeper water dewpoint depression. The calculator uses GPSA Figure 20-63 equilibrium data to determine the dewpoint achievable at a given TEG purity, contactor temperature, and pressure.
The typical US pipeline specification is 7 lb H2O/MMscf maximum. The calculator determines whether the selected TEG purity and operating conditions can meet this specification and recommends adjustments if needed.
TEG contactors typically operate at 300-1500 psia. Higher pressure increases water absorption capacity and improves achievable dewpoint depression. The calculator uses McKetta-Wehe charts to determine water content at the equilibrium dewpoint.
An approach temperature of +5-15°F is added to the equilibrium dewpoint to account for real-world contactor performance. This adjustment reflects that actual contactors do not achieve perfect equilibrium between the gas and lean TEG.