The document provides an overview of the ash handling system at a power plant, including bottom ash, fly ash, and slurry handling systems. It describes the different types of ash generated and their quantities. The bottom ash system uses intermittent water-impounded hoppers and jet pumps to remove ash from the bottom of boilers. The fly ash system can operate in either wet or dry mode to transport ash from electrostatic precipitators to storage via slurry trenches or pressurized pipes. Ash water is used throughout the systems and is pumped from a central ash water pump house. Ash slurry is transported via pipelines to the large ash dyke area for disposal and storage.

2. Ash handling system overview
 Bottom ash handling system.
 Fly ash handling system (both wet &
dry).
 Slurry handling system from slurry
pump house to ash dyke.
 Ash water system.
 Ash water recirculation system.

3. Types of ash Generated
 Fly ash ( approx 80%)
 Bottom ash ( approx 20%)
N.B:-- say 1 kg of coal contains 30 to 40 % of
ash. Let in a day of 24 hrs 20 MT of coal
burns then ash quantity = 20000x30 %=
6000 MT. So Bottom ash =6000x20%=1200
MT & Fly ash=6000x80%=4800 MT

5. System consists of ‘W’- type
water impounded hopper with
jet pumps for intermittent
removal of bottom ash. (WW)
Bottom ash system

6. Components of the system are :----
1. Water impounded ash hoppers
2. Hopper Feed gate- 4 no & 6 no
3. Clinker grinders-4 no & 6 no
4. Jet pumps
5. BA slurry line to ash slurry pump house
6. Slurry Transportation to ash dyke by
means of ash disposal pumps.
Intermittent type water impounded
hoppers & Jet pump system.

7. BOTTOM ASH HANDLING SYSTEM

8. W- Shaped Bottom Ash Hopper

9. Bottom Ash Hopper- Feed Gate
Arrangement

10. Feed Gate & Grinder Rolls

11. Flow diagram of hopper overflow water in jet
pump system
BA
HOPPER Over
Flow
Tank
Settling
Tank
Surge
Tank
Sludge to Ash
Slurry pump
House sump.
Over
Flow pumps
Sludge
Pump
To ash water
P/p house by
Gravity

12. Ash Removal System from
Economizer,PAPH,SAPH
Ash collected in Economizer,
PAPH & SAPH hoppers drop
continuously through Vertical
pipe connected to the
Flushing apparatus beneath
each of the hoppers
For the flushing apparatus
water is provided from FAHPs.

13. Fly ash handling system
The fly ash handling system
consists of two modes of
operation, Viz
1.Wet mode operation and
2.Dry mode operation.

14. Ash evacuation from ESP hoppers
1. Wet mode:--Ash evacuated from ESP
hoppers through vacuum pumps & fed
to wetting head (vacuum system) and
collector tank units where ash is mixed
with water & resultant slurry is
discharged to slurry trenches.
2. Dry mode :-- Ash evacuated from ESP
hoppers through vacuum pumps &
collected in Buffer hoppers & Air lock
tank, is transported to storage silo by
compressed air (pressure conveying
system) through pressure conveying pipe
lines.

15. ESP- Electrostatic Precipitator

16. ESP Internals

17. ESP Evacuation System

18. Components of wet fly ash
system
1.ESP hopper
2.Plate valve for isolation .
3.Material Handling Valve (MHV)
4.Piping up to wetting head
5.Wetting head
6.Air washer
7.Vacuum pump
8.Trench up to ash slurry pump house.

19. Flow diagram of wet fly ash system
ESP
Trench 2 ASPH
Air outlet
M H V
Plate valve
Vacuum pump
Wetting
head
Air washer
Air in

20. FLOW PATH OF WET MODE FLY ASH
ESP HOPPER
WETTING HEAD
AIR WASHER
DISCHARGE PIPE
SEAL BOX
FLY ASH SLURRY TRENCH
ASH SLURRY PUMP HOUSE
AIR TO
VACUUM
PUMP

21. Flow diagram of Dry fly ash system
Silo
TRUCK
Buffer
hopper ESP Hopper
Vacuum
pump
ALT
ALT
Air outlet
Bag filter
Bag filter
Air from TAC
Primary
& secondary
Collector

22. Flow path of dry mode fly ash
ESP Hopper
Buffer hopper
Air lock tank
Ash storage silo
Truck/volvo/wagons
Air to
Vacuum pump

23. Wet & Dry Mode

24. Ash water pump house
Ash water pumps
Ash water pumps
Ash water sump
BA HP
Pumps BA LP
Pumps
Flushing
Water Pump
FA HP
Pumps
From Raw
water pumps
From CW
Blow down
From Ash Water
Recirculation
System
From BA Overflow
Pumps

25. Ash water pumps
(located in ash water pump house)
1.Bottom ash HP water pumps- 2/2 no.
2.Bottom ash LP water pumps-3/5 no.
3.Flushing water pump-1/1 no.
4.Fly ash HP water pumps-3/5 no.

26. Use of Ash Water Pumps
 BA HP pump
 BA LP pump
 Flushing water
pump
 Fly ash HP pump
 Boiler bottom area
 Boiler bottom area &
make up of BAH/ASPH
sumps.
 Flushing of ash disposal
lines.
 Wetting head of fly ash
system,SAPH, PAPH, Eco
hoppers.

27. Ash Water Pump House

28. Ash disposal system
 Sump plug valves-4no
 Ash sluice trench
 Gear box and Fluid coupling
 Ash slurry valves
 Slurry sump liners
 Drain pumps
 Disposal pipes and fittings
 Ash Disposal lines to dyke.

29. Flushing Water Line
LP seal
water HP
Seal water

30. Ash Slurry Pump House

31. Ash Disposal Lines

32. AWRPH
ASH DYKE
STAGE- I
Lagoon-1
490 Acres
ASH DYKE
STAGE -I
Lagoon-2
440 Acres
OVER FLOW
LAGOON
ASH
DYKE
STAGE –II
230 Acres
ASH DISPOSAL PIPE LAYOUT
5800S
2200W
200E
400S

33. Ash Dyke , Area- 360 Acre, Capacity-
122 Lac Cum

34. Sprinklers System at Ash Dyke

35. Raising at Ash Dyke

36. Thank UA