Stripping Purpose

Crude oil, condensate, and refined products contain dissolved light ends causing excessive vapor pressure, storage tank emissions, and product instability. Stripping columns remove these volatiles using counter-current gas contact achieving target vapor pressure specifications.

Column Design

Vertical vessel with oil feed near top, stripping section with trays or packing, steam or gas inlet at bottom creating upward flow, overhead vapor outlet to condenser, stripped oil outlet at bottom, reboiler when required. Height provides contact stages for target light ends removal.

Stripping Medium

Steam most common providing heat and stripping vapor. Inert gas like nitrogen used when water contamination unacceptable. Air unsuitable due to oxidation and flammability concerns. Medium selection depends on product specifications and downstream processing.

Operating Principle

Oil flows downward contacting rising steam or gas. Light hydrocarbons transfer from liquid to vapor phase. Vapor exits overhead carrying stripped components. Reboiler or steam injection provides energy driving vaporization. Proper temperature and flow rates achieve target stripping.

Material Selection

Carbon steel for hydrocarbon service. Stainless steel where corrosion from steam condensate or stripped components concerns. Design handles operating temperature typically 100-150C. Materials resist thermal cycling during startup and shutdown.

Applications

Crude oil stabilization before refining, condensate vapor pressure reduction, naphtha stabilization, gasoline stripping, slop oil processing, and any operation requiring light hydrocarbon removal from liquid streams.

Vapor Pressure Control

Stripping reduces Reid vapor pressure meeting storage, transport, and product specifications. Critical for preventing tank overpressure, atmospheric emissions, and flash losses. Target typically 9-14 psia for gasoline, lower for crude oil.

Steam Consumption

Typical steam rates 0.5-2% by weight of oil feed. Lower rates insufficient stripping. Excessive steam wastes energy and increases overhead condensate. Optimization balances stripping efficiency versus operating costs.

Overhead System

Condenser recovers stripped hydrocarbons as liquid for processing or recovery. Water separator removes steam condensate. Gas phase contains non-condensables routing to fuel or flare. System design depends on stripped component value and facility configuration.

Temperature Control

Bottom temperature critical for stripping efficiency typically 110-140C for crude stabilization. Too low provides insufficient stripping. Excessive temperature causes product degradation or heavy ends vaporization. Control maintains optimal conditions.

Performance Benefits

Reduces vapor pressure meeting product specifications. Prevents storage tank emissions and losses. Improves product stability. Steam stripping proven technology with low capital cost and reliable operation.

Construction Standards

Design per ASME Section VIII for operating pressure. Tray or packing design for steam-hydrocarbon service. Materials handle thermal duty. Complete documentation with mass transfer calculations and performance guarantees.

ERGIL oil stripping columns provide efficient light ends removal stabilizing crude oil and refined products for safe storage and transport.