Contactor Function

Sour gas enters the tower bottom flowing upward through structured packing or trays while lean amine enters at the top flowing downward by gravity. This countercurrent contact maximizes mass transfer as amine chemically absorbs acid gases. Sweet gas exits overhead meeting H₂S specifications typically below 4 ppm. Rich amine saturated with acid gases exits the bottom flowing to regeneration for solution reconcentration.

Tower Design

ERGIL engineers contactors based on gas flow rate, inlet acid gas concentration, required removal efficiency, operating pressure, and amine type. Tower diameter sized to prevent flooding while maintaining efficient contact. Packing height or tray count provides required mass transfer stages. Carbon steel construction with corrosion allowances or stainless steel for severe service conditions.

Internal Components

Gas inlet distributor ensures uniform flow across tower cross-section preventing channeling. Structured packing provides high surface area for gas-liquid contact with low pressure drop, typically 2-6 inches water per theoretical stage. Liquid redistributors in tall towers maintain even amine distribution. Mist eliminators at gas outlet capture entrained amine droplets preventing carryover losses. Chimney trays handle upstream liquid slugs protecting packing from damage.

Operating Conditions

Typical operating pressures match upstream gas pressure from 50 to 1500 psig. Temperatures generally 35-65°C with inlet gas cooling often employed to optimize absorption efficiency. Lower temperatures favor acid gas absorption but must remain above hydrate formation conditions. Amine circulation rates sized to provide adequate treating capacity with typical lean amine loading 0.25-0.40 moles acid gas per mole amine.

Applications

Natural gas sweetening removing H₂S and CO₂, refinery hydrogen purification, syngas treating, biogas upgrading, and sour water stripper overhead treating. Handles sweet to extremely sour gas compositions across production facilities, gas plants, refineries, and chemical operations. Capacities from 1 to 200 MMSCFD depending on tower sizing.

Material Considerations

Carbon steel suitable for most applications with proper amine inhibitor programs. Stainless steel 304 or 316 for high acid gas loading, elevated temperatures, or corrosive contaminants. Packing materials typically stainless steel or special alloys resisting amine service. All materials selected per NACE standards for sour environments.

Performance Features

Efficient absorption achieves specification with optimized amine circulation minimizing regeneration costs. Low pressure drop preserves gas pressure for downstream operations. Proven packing or tray designs resist fouling and provide long service life. Designed per ASME Section VIII with full code compliance and pressure vessel certification.

ERGIL amine contactor towers deliver reliable acid gas removal as standalone vessels or integrated within complete sweetening packages for diverse gas treating applications.