presentation

1. Feedwater Heaters

2. What is feedwater heater
Components in which fluid exiting the condenser is
preheated by Extracted steam from turbines

3. •
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4. Why are feedwater heaters used
?
•
To reduce thermal shock in boiler
.
•
To reduce irreversibility by rapid heat transfer
.
•
To reduce boiler load
.
•
Regenerative feedwater heaters are employed in steam power plants to
improve the cycle efficiency
.

5. •
Also it increases the steam flow rate and reduces the steam flow to the
condenser
.
•
They raise the temperature of the feedwater before it enters the
economizer
.

6. Types of Feedwater heaters
Open Feedwater heaters Closed feedwater heaters

7. Advantages of open feedwater heaters
•
Faster heat rate between steam and saturated water, because of direct
contact of both fluids
.
•
Direct contact heat exchanger is generally less expensive compared to other
type, and easier maintenance process
.

8. Disadvantages of open feedwater heaters
•
Because of the pressure difference in all three state of turbine, condenser,
and boiler, additional pump is required for each feedwater, which means
additional initial cost and maintenance cost
.
•
Adding components through which the fluid flows increase the loss by
friction and heat loss to surrounding
.

9. Advantages of closed feedwater heaters
•
We don
’
t need a pump for each feedwater heater because of different
pressure
.
•
Reduce the irreversibility involved in steam generation and hence increase
efficiency
.
•
It helps to avoid thermal shock to the boiler metal when the feedwater is
introduced back into the steam cycle
.

10. Disadvantages of closed feedwater heaters
•
More complex
.
•
More expensive
.
•
Less heat transfer
.
•
Less effective because no mixing between the fluids
.

11. Presented by : Mohammed Almohani
Supervisor : Dr.eng. Abdulmalek. Momin