Heat Recovery Function

Cold sour water feed containing dissolved H₂S and ammonia at 40-60°C requires heating to 90-120°C for effective stripping. Hot stripped water exits column bottom at 100-130°C needing cooling before discharge. The exchanger transfers heat between streams, preheating feed while cooling product, recovering 60-80% of sensible heat. This integration reduces reboiler steam consumption and cooling water requirements significantly.

Design Configuration

Shell-and-tube construction with hot bottoms on shell side and cold feed on tube side. ERGIL engineers exchangers based on water flow rate, temperature approach, and allowable pressure drop. Multiple tube passes optimize heat transfer. Design accommodates fouling from hydrocarbon carryover, iron sulfide deposits, and scaling requiring periodic cleaning maintenance.

Material Selection

Stainless steel 316 construction resists corrosion from H₂S, ammonia, chlorides, and organic acids in sour water service. Carbon steel with corrosion allowances suitable for less severe applications. Tube-side design enables mechanical or chemical cleaning addressing fouling from contaminants. Construction per ASME Section VIII with materials meeting NACE requirements for sour service.

Performance Benefits

Reduces reboiler steam consumption 50-70% lowering operating costs with typical payback under 24 months. Decreases cooling water duty for treated water discharge. Improves stripper performance through adequate feed preheat. Simple proven technology essential in energy-efficient sour water treatment. Supports refinery sustainability goals through energy recovery.

Applications

Refinery sour water stripping units treating water from crude distillation, catalytic cracking, coking, and hydrotreating operations. Petrochemical facilities processing contaminated water streams. Gas processing plants treating produced water. Serves systems handling 50-5,000 GPM sour water flows across diverse refining operations.

Control Features

Temperature monitoring verifies proper heat transfer performance. Bypass valves enable temperature control during varying loads or startup. Differential pressure indicators detect fouling requiring cleaning. Integration with stripper controls optimizes overall water treatment efficiency.

Operational Considerations

Fouling from hydrocarbons, iron sulfide, and scale requires periodic cleaning maintaining heat transfer efficiency. Design includes adequate fouling factors and cleaning access. Materials resist corrosive sour water environment. Proper operation and maintenance ensure long-term reliable performance.

Construction Standards

Design per ASME Section VIII or TEMA standards with full code compliance. Materials rated for sour water corrosion and temperatures to 150°C. Removable tube bundles facilitate maintenance. Hydrostatic testing validates integrity. Complete documentation includes heat transfer calculations and fouling considerations.

ERGIL feed-bottoms exchangers deliver essential heat recovery in sour water stripping systems reducing energy consumption and improving refinery water treatment economics.