Plate type heat exchangers contains a large number of corrugated metal plates according to the pressure of operations these will be fixed as a bundle. These are useful in medium and low pressure operations.
Advantages of plate type Heat exchangers:
- High surface area(high heat transfer rates)
- Compact in size(Occupies less area for installation)
- Very useful in case of handling refrigerants like NH3, Ethylene oxide etc.
- Compared to other heat exchangers cost of installation and fabrication is also low.
- Easy of cleaning: Heat exchanger can be easily dismantled for inspection and cleaning.
- Give good results for low temperature operations.
- It can not be used for vacuum operations because of it's compact plate structure there is a change for rupture of plates.
Disadvantages of plate type Heat exchangers:
- Can not with stand high pressures, due to gasket failure at high pressures.
- It can not be used in handling dirty liquids because, as the plates are very close to each other there may be a chance of clogging.
- Cannot be used for High temperature operations as there is a chance of melting of gasket at localized points
- Pressure drop across the Heat Exchanger is high which in turn will increase our pumping cost.
- Maximum possibility of leakage is also a disadvantage in this one.
Heat Transfer Equation
Simple equation Q=UA∆T
Where,
Q = Total heat transfer rate
U = Overall Heat transfer coefficient
A = Heat transfer area
∆T = Temperature difference of cold and hot streams
Maintenance
Cleaning is the main issue with these type of heat exchangers. Some times these requires chemical cleaning to avoid damage to the plate because of hydrojetting.
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