Stacked Design

Lower separator sits on grade or supports. Upper separator mounts directly above using lower vessel as structural base. Interstage piping short and integrated. Compact vertical arrangement reduces footprint by 40-60% versus side-by-side configuration.

Configuration Options

Two-stage gas-liquid separation with secondary polishing. Three-phase lower stage with two-phase upper cleanup. Staged pressure reduction with flash separation. Application-specific arrangement optimizes separation sequence for process requirements.

Operating Principle

Lower stage handles bulk separation at higher pressure or heavier loading. Upper stage provides polishing, operates at lower pressure, or separates different phase. Gravity flow between stages possible eliminating pumps. Interstage connections short reducing piping costs.

Space Advantages

Single foundation supports both vessels. Minimal plot area suits offshore platforms, brownfield retrofits, or space-constrained facilities. Vertical piping between stages shorter than horizontal runs. Combined structure reduces steel and installation costs.

Material Selection

Carbon steel or stainless steel depending on service. Independent pressure ratings for each vessel. Shared support structure designed for combined weight plus seismic and wind loads. Upper vessel access via platform or ladder.

Applications

Offshore production separators maximizing deck space, refinery units in congested areas, gas plant separation trains, wellhead facilities, and any application where plot space limited but two-stage separation required.

Pressure Ratings

Each vessel designed for respective operating pressure. Lower stage typically higher pressure handling upstream conditions. Upper stage lower pressure for flash or atmospheric separation. Independent relief systems protect each vessel.

Level Control

Both vessels have independent level instruments and controls. Interstage flow coordination prevents flooding or gas breakthrough. Automated systems manage inventory in both stages maintaining optimal operation.

Maintenance Access

Platform around upper vessel enables inspection and maintenance. Crane access required for internals removal or vessel replacement. Design considers maintenance requirements during engineering phase.

Performance Benefits

Reduces plot space 40-60% versus conventional layout. Lower installation costs with shared structure. Shorter piping reduces pressure drop and capital cost. Proven configuration widely used offshore and congested facilities.

Construction Standards

Each vessel designed per ASME Section VIII for respective pressure. Structural support for combined load per applicable building codes. Complete system documentation with mechanical calculations for stacked arrangement.

ERGIL piggy back separators deliver two-stage separation in compact vertical configuration optimizing space utilization in constrained industrial facilities.