Drum Function

Overhead vapors from distillation columns condense in exchangers then flow to reflux drum. Vessel provides vapor-liquid separation, surge volume buffering condenser variations, and liquid inventory enabling independent control of reflux returned to column and net overhead product. Proper sizing ensures stable operation during flow disturbances.

Vessel Design

Horizontal configuration with vapor inlet from condenser, mist eliminator removing entrained droplets, liquid space providing 5-15 minutes residence time, reflux outlet feeding column top, and product outlet to storage or downstream processing. ERGIL sizes drums based on overhead flow rate, required surge time, and control response.

Operating Conditions

Design pressure accommodates column overhead pressure plus control margin typically 15-150 psig. Temperature ratings handle condensed liquid conditions 30-120°C. Vapor space sizing prevents liquid carryover during surges. Materials suitable for overhead product composition including water, hydrocarbons, or chemicals.

Material Selection

Carbon steel construction for hydrocarbon service. Stainless steel for corrosive streams containing acids, water, or chlorides. Internal components resist condensation corrosion. Design per ASME Section VIII with materials meeting process requirements.

Applications

Crude distillation unit overhead drums, naphtha stabilizer reflux accumulation, gas plant deethanizer and depropanizer drums, condensate fractionation reflux vessels, and any distillation requiring overhead liquid collection. Serves refineries, gas plants, and petrochemical facilities across diverse separation operations.

Level Control

Level transmitter controls reflux flow maintaining column operation. Independent control valve manages product takeoff. High-level alarm prevents overflow. Low-level protection prevents pump cavitation or gas breakthrough. Ratio control maintains reflux-to-product split optimizing separation.

Control Integration

Level control cascade with column pressure maintaining hydraulic balance. Reflux ratio adjustment optimizes separation efficiency. Integration with column temperature profile enables feed-forward control. Automated operation with DCS systems coordinates distillation performance.

Performance Benefits

Provides essential surge capacity for stable distillation operation. Enables independent reflux and product control. Vapor-liquid separation prevents column flooding. Simple horizontal vessel with proven reliability. Minimal pressure drop in overhead system.

Construction Standards

Design per ASME Section VIII Division 1 with appropriate materials. Relief valve protection against blocked outlets. Proper nozzle sizing for inlet distribution and outlet flow. Complete documentation with surge calculations and hydraulic design.

Operational Advantages

Reliable liquid accumulation with simple level control. Accommodates process variations without column upset. Easy maintenance with accessible internals. Supports optimal fractionation through proper reflux management.

ERGIL reflux drums deliver dependable overhead liquid collection ensuring stable distillation control and optimal separation performance in fractionation operations.