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Fouling
Though fouling in heat exchangers cannot be eliminated , it can definitely be controlled and reduced .
( Sedimentation ) particles
DEPOSITION
( Crystallisation ) ions the velocity of fluid falls below critical levels . This type of fouling can be helped with the proper management of the combined particles / fluid . In reality , more than one fouling mechanism is present in many processes and their combined effect is phenomenal and can be much severe than expected . Various deposition and removal processes during fouling can be seen at glance in below diagram .
How to monitor your heat exchanger Hence it becomes very important to have data points and information to precisely monitor a heat exchanger . The parameters which can be measured for monitoring are inlet and outlet temperature for cold fluid , inlet and outlet temperature of outlet fluid , mass flow rates for both cold
Flow direction
Heat flow
Dissolution
REMOVAL
Spalling Erosion and hot fluids , and hot and cold fluid pressure change across the heat exchanger . To keep the heat exchange system running effectively it is advisable to consider some of these points : 1 ) understand all available data associated with pressure , flow , and temperature indication ; 2 ) find out and assess what flows , pressures , and temperatures are recorded by operators in their daily routines ; 3 ) continuously check the pressure - differential pressure tracking on shell side or tube side of a heat exchanger can be extremely valuable information - if the differential pressure builds up over a period it means something is restricting the flow ; and 4 ) to record temperature data information , it is best to utilise a handheld temperature gun , infrared temperature guns can help you monitor the temperature of the system effectively throughout its operation . By utilising today ’ s technology tracking the system manually , any process industry can keep track of a heat exchanger . Chemical cleaning methods by acid and alkali with combination of rinsing can be used to clear the fouling in heat exchangers . Chemical cleaning can clean fouling effectively without the need to dismantle the heat exchanger . This process enables the heat exchanger to be operational in reduced time without taking it offline .
Heat transfer surface The various deposition and removal processes during fouling .
Deposits
Designing against fouling In the designing stage , fouling factor is taken into consideration . Different methods of heat exchanger construction are carried out by manufacturers to help provide an increased heat transfer area that may be affected by fouling . During manufacturing , many
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