Cooling Mechanism

Hot vapor enters and contacts cold quench liquid through spray nozzles or liquid pool. Direct contact transfers heat faster than shell-and-tube exchangers. Water, oil, or recycled product serves as quench medium depending on process requirements. Vapor cools, heavy ends condense, and cooled gas exits overhead while liquid drains for recirculation or processing.

Vessel Design

Vertical tower with hot gas inlet at bottom or side, spray section with multiple nozzle levels distributing quench liquid, vapor-liquid contact zone, mist eliminator removing entrained droplets, cooled gas outlet at top, and liquid sump with pump recirculation. Height and diameter depend on gas flow, required cooling, and liquid-to-gas ratio.

Applications

Ethylene cracker quench systems cooling pyrolysis gas, coker vapor quench protecting fractionator, catalytic cracker vapor cooling, gasifier syngas quench, and any high-temperature process needing rapid cooling. Common in petrochemical plants, refineries, and gasification facilities.

Quench Medium

Water quench systems use treated water or condensate. Oil quench recirculates heavy product or slurry oil. Selection depends on downstream separation requirements, fouling potential, and thermal properties. Water provides maximum cooling but creates two phases. Oil quench keeps hydrocarbons single-phase.

Temperature Control

Quench liquid flow rate controls outlet gas temperature. More liquid flow increases cooling. Automated valve modulation responds to temperature changes maintaining setpoint. Recirculation loop with heat exchanger removes absorbed heat keeping quench liquid cool.

Material Selection

Inlet section uses alloy steel or refractory lining for high-temperature resistance. Lower sections use carbon steel as temperatures drop. Thermal expansion joints accommodate temperature gradients. Spray nozzles resist erosion and plugging from solids.

Fouling Management

Heavy components and coke particles deposit on internals. Regular cleaning using high-pressure water maintains performance. Some designs include soot blowers or rodding access. Proper liquid distribution minimizes dry spots where fouling accelerates.

Performance Benefits

Fast cooling protects metallurgy of downstream equipment from high temperatures. Direct contact costs less than fired heaters or large heat exchangers. Handles dirty streams with solids that would foul tube exchangers. Simple robust design with fewer failure points.

Control Integration

Temperature transmitters on inlet and outlet track cooling performance. Flow controllers adjust quench liquid rate. Level control in sump manages inventory. High-temperature alarms protect against quench liquid interruption that could damage vessel and downstream equipment.

Construction Standards

Design per ASME Section VIII with materials for thermal cycling and process chemistry. Expansion analysis prevents thermal stress failures. Relief sizing accounts for quench liquid vaporization scenarios. Complete documentation with thermal calculations and material specifications.

ERGIL quench drums protect downstream equipment through fast direct-contact cooling in high-temperature petrochemical and refining processes.