1. Furnace Heat Transfer & Steam Generation
P M V Subbarao
Professor
Mechanical Engineering Department
I I T Delhi
Optimal Blending of Two Thermal Actions…

2. Religious to Secular Attitude of Water flowing thru Furnace (Water) Walls

3. Natural Circulation Steam Generator

4. Natural Circulation Nuclear Reactor

5. Religious to Secular Attitude of Water flowing thru Furnace (Water) Walls

6. Forced Circulation Steam Generator

7. Forced Circulation Nuclear Reactor

8. Once Through Steam Generator
Once-through tangential fired
Max. continuous rating: 520 kg/s Max.Steam temperature outlet: 540°C Live steam pressure outlet: 18,3 MPa

9. Super Critical Nuclear Reactor

10. The Basics of Flow Boiling….

11. Religious to Secular Attitude of Water flowing thru Furnace (Water) Walls

12. Subcritical Boiling process in Tubular Geometries
Heat Input
Water
Steam
Partial Steam Generation
Complete or Once-through Generation
Water

13. Tube Wall Temperature : Sub-critical Flow Boiling
Newton’s Law of Cooling:

14. Subcritical Flow Boiling & Mechanism of Heat Transfer

15. Religious to Secular Attitude

16. Tube Wall Temperature : Super-critical Flow Boiling
Newton’s Invention:

17. Spiral Tubing for Uniform Heating

18. 1000MW BABCOCK-HITACH

19. Paths of Steam and Gas
Drum
Water walls
Economizer

20. Thermal Structure of A Boiler Furnace
DPNL SH
Platen SHTR R H T
LTSH
Economiser
APH ESP ID Fan
drum
Furnace
BCW
pump
Bottom ash
stack

21. Radiative Super Heaters

22. Convective Superheater

23. Reheater
The pressure drop inside reheater tubes has an important adverse effect on the efficiency of turbine.
Pressure drop through the reheater should be kept as low as possible.
The tube diameter : 42 – 60mm.
The design is similar to convective superheaters.

24. Economizer
The economizer preheats the feed water by utilizing the residual heat of the flue gas.
It reduces the exhaust gas temperature and saves the fuel.
Modern power plants use steel-tube-type economizers.
Design Configuration: divided into several sections : 0.6 – 0.8 m gap

25. Air Pre-Heater
An air pre-heater heats the combustion air where it is economically feasible.
The pre-heating helps the following:
Igniting the fuel.
Improving combustion.
Drying the pulverized coal in pulverizer.
Reducing the stack gas temperature and increasing the boiler efficiency.
There are three types of air heaters:
Recuperative
Rotary regenerative
Heat pipe

26. Rotary or Regenerative Air Pre-Heater

27. Exhaust gas heat recovery system Configuration and temperature profile in air heater

28. Steam Temperatures Gas Temperatures Platen Super Heater:
Inlet Temperature : C
Outlet Temperature (FEGT) : C
Final Super Heater:
Inlet Temperature: C
Outlet Temperature: C
Reheater:
Inlet Temperature: C
Outlet Temperature: C
Low Temperature Super Heater:
Inlet Temperature: C
Outlet Temperature: C
Economizer:
Inlet Temperature: C
Outlet Temperature: C
Platen Super Heater:
Inlet Temperature: 404 0C
Outlet Temperature: 475 0C
Final Super Heater:
Inlet Temperature: 475 0C
Outlet Temperature: 540 0C
Reheater:
Inlet Temperature: 345 0C
Outlet Temperature: 5400C
Low Temperature Super Heater:
Inlet Temperature: 3590C
Outlet Temperature: 404 0C
Economizer:
Inlet Temperature: 254 0C
Outlet Temperature: 302 0C

29. Flue Gas Temperature At different regions of Furnace
Design
Calculated 1
Adiabatic Flame Temp (K)
1957
1966 2
FEGT (0C)
1102
1117 3
Platen SH-I Outlet (0C)
932
951 4
Platen SH-II Outlet-I outlet (0C)
859
878 5
RH 3rd & 2nd outlet (0C)
595
604 6
RH 1st Stage outlet (0C)
510
531 7
Economiser outlet (0C)
385
398 8
APH Outlet (0C)
138
151

30. Thermodynamic Cycle of air & Gas and flow diagram

31. Bird View of Power Plant Steam Generator

32. Steam Generator Draught SystemFD
Fan
Duct
APH
Furnace
Back
pass
ESP ID
Chimney

33. Combustion Losses
C & R losses
Hot Exhaust Gas
losses
APH
Economizer
CSH
Pendent SH
Reheater
Platen SH
Furnace absorption