Compression Effects

First-stage compression heats syngas 50-100C. Intercooler drops temperature to near-ambient for efficient second-stage operation. Cooling condenses water vapor and any remaining heavy compounds. Without removal, liquids damage downstream compression stages.

Separator Design

Vertical vessel between first stage discharge and intercooler or after cooling before second stage suction. Gas inlet, liquid collection zone, mist eliminator, gas outlet to next stage, and drain to treatment. Simple design focuses on reliable liquid knockout.

Operating Pressure

Interstage pressure typically 100-400 psig for two-stage systems, varies with compression ratio. Design accommodates pressure between stages with safety margin. Lower than suction scrubber pressure but higher than most production separators.

Condensate Volume

Water from syngas saturation condenses during cooling. Quantity depends on compression ratio, cooling effectiveness, and inlet moisture. Tar compounds may also condense. Vessel sizing handles maximum liquid rates with surge capacity.

Material Selection

Stainless steel resists corrosion from syngas components and acidic condensate. Design handles thermal cycling during startup and load changes. Drain connections sized for condensate viscosity including potential tar content.

Level Control

Level switches activate drain valves removing condensate to closed treatment systems. High-level alarm protects against carryover to second stage. Simple control suits automated compressor operation without constant attendance.

Applications

Coal gasification syngas compression trains, biomass gasification facilities, steam methane reformer syngas handling, waste-to-energy gasification plants, and any multi-stage syngas compression. Protects equipment while maximizing compression efficiency.

Performance Impact

Dry gas between stages compresses more efficiently. Removes liquids that would reduce volumetric efficiency and cause mechanical problems. Prevents water hammer from liquid accumulation. Maintains predictable compression performance.

Integration

Coordinates with intercooler operation and second-stage suction conditions. Condensate combines with other process wastewater for treatment. System design considers overall compression train performance and liquid handling requirements.

Construction Standards

Design per ASME Section VIII for interstage pressure. Materials suitable for syngas condensate. Drain system handles corrosive liquids. Relief protection prevents overpressure. Complete documentation with separator calculations.

ERGIL first-stage discharge separators protect multi-stage syngas compressors while improving compression efficiency through interstage liquid removal.