Heat ExchangersHeat Exchangers

Today’s AgendaToday’s Agenda

• Purpose of Heat Exchangers• Three Methods of Temperature

Transfer• Primary Parts• Operation of Heat Exchanger• Applications • Hazards

Purpose of Heat Purpose of Heat ExchangersExchangers

• Transfer heat• Increase production• Prevent thermal shock• Safety• Prevent overheating

Heat Exchange may serve Heat Exchange may serve to:to:

Increase production (pre-heater on reactor)

Prevent thermal shock (pre-heater on distillation column)

Change phase (cool vapor to condense it, or heat a liquid to vaporize it)

Prevent overheating of a process fluid Recover “waste” heat for useful

purposes

Applications of Tube and Applications of Tube and Shell ExchangersShell Exchangers

• Reboiler – Forced feed – Thermosiphon

• Heater/preheater• Aftercooler• Condenser• Chiller• Interchanger

Three Methods of Three Methods of Temperature TransferTemperature Transfer

• Convection• Conduction• Radiation• Convection and conduction is

mostly what occurs in HE

Parts of a Shell and Tube Parts of a Shell and Tube HEHE

• Head• Shell• Tubes – plain or finned• Tube Sheet – keeps tube-side isolated

from shell-side• Baffles – help w/ convection• Tie Rods – support tubes• Nozzles – shell and tube-side

Identify Primary Identify Primary PartsParts

• Tube inlet and outlet• Shell inlet and outlet• Baffle• Exchanger head (channel type)• Tube bundle

Single Pass Counter Flow Single Pass Counter Flow ExchangerExchanger

Operation of Tube and Operation of Tube and ShellShell

ExchangersExchangers• Typical Tube and Shell

Exchangers• Main Components

HazardsHazards

• Personal Safety– Head knockers (valves/pipes)– Goggles or faceshield when draining or venting– Contact w/ chemical hazards– Temp. hazards– Pressure hazards

• Environmental hazards– Leaks

• Equipment– Thermal shock– Fouling

Monitoring and Monitoring and MaintenanceMaintenance

• Look• Listen• Feel

Heat Exchanger Heat Exchanger HazardsHazards

• Individual• Equipment• Production• Environment

Single Pass Shell/Tube Single Pass Shell/Tube CondenserCondenser

Tube FinsTube Fins

Tube BundleTube Bundle

U-Tube BundleU-Tube Bundle

Two Pass Floating Head Two Pass Floating Head Heat ExchangerHeat Exchanger

Kettle Type ReboilerKettle Type Reboiler

Multi Pass Floating Head Multi Pass Floating Head Heat ExchangerHeat Exchanger

Heat Exchanger Heat Exchanger SymbolsSymbols