Process Function

Natural gas cooling reduces temperature to condense heavier hydrocarbons, achieving required hydrocarbon dew point specifications or preparing gas for cryogenic NGL recovery. The cold separator receives chilled gas from heat exchangers or refrigeration systems, providing residence time for liquid droplets to coalesce and settle by gravity. Gas exits the top meeting pipeline specifications while liquids drain from the bottom for stabilization or processing. Efficient separation at low temperatures prevents liquid carryover that could freeze downstream equipment or violate custody transfer specifications.

Design Features

ERGIL engineers cold separators for low-temperature service with materials preventing brittle fracture. Impact-tested carbon steel or aluminum construction per ASME Section VIII requirements. Internal mist eliminators capture submicron droplets. Inlet diverters reduce gas velocity enabling gravity separation. Vortex breakers prevent gas entrainment in liquid outlets. Insulation and heat tracing maintain operating temperatures and prevent external condensation. Boot sections provide liquid level control with cryogenic-rated instruments.

Temperature Considerations

Material selection addresses low-temperature toughness requirements. Charpy impact testing verifies steel properties at operating conditions. Gaskets and seals rated for cryogenic service. Thermal expansion accommodations prevent stress during temperature cycling. External insulation minimizes heat gain and maintains process temperatures. Heat tracing on drain lines prevents freezing and ensures liquid flow.

Applications

Gas processing plants with refrigeration systems, turbo-expander inlet separation, dew point control skids for pipeline conditioning, LNG facilities pre-treatment, and cryogenic NGL recovery units. Operates downstream of gas-gas heat exchangers, propane or mixed refrigerant chillers, and Joule-Thomson expansion valves across pressures from 300 to 1500 psig.

Operational Features

Level control systems manage liquid removal preventing overflow or gas breakthrough. Temperature monitoring ensures proper operating conditions. Pressure relief protection against overpressure from blockage or upset conditions. Quick liquid dumps handle slug flow from upstream equipment. Automated control integration with refrigeration systems optimizes performance.

Construction Standards

ASME Section VIII Division 1 design with low-temperature material specifications. Full radiographic examination of welds. Hydrostatic and pneumatic testing per code requirements. NACE compliance for sour service when applicable. Seismic and wind load calculations per site requirements. Complete documentation including material test reports and NDE records.

ERGIL cold separators provide reliable liquid-gas separation in low-temperature service with proven designs ensuring safe, efficient operation in demanding cryogenic applications.