1. CFBC BOILER UPDATE
Coal Based Circulating Fluidized Bed Combustion (CFBC) Boiler Technology
By :Asad Mehmood

2. Objective Introduction to FFBL Coal Power Plant (CPP) Project
Over-view of CPP Project
Power Plant Classification
Types of Coal based boilers Technology
Selection of CFB Boiler Technology
Design Specifications of CFB Boilers
Main Equipments
Coal Specification & Consumption
Emissions and mitigation measures

3. CPP PROJECT – INTRODUCTION
CPP Project AIM
Alternate fuel for steam and power generation owing to shortage of Natural Gas.
Meeting FFBL Steam and Power requirements
Additional margins for Power Export to National grid
Main Components of CPP Project
2 x 250 MeT/hr Circulating Fluidized Bed (CFB) Boilers
3 x STG’s at 60 Hz
1 x BPSTG’s or BPSTG cum Condensing at 60 Hz
1 x 55 MWe STG’s at 50 Hz for Power Export

4. Over-view of Flow Schematic
New Coal Power Plant (CPP) Project
FFBL Existing Plants
Ammonia-Urea-DAP-Utilities Fertilizer’s Plant
Coal
(Mainly Indonesia / South Africa & local Coal)
Utilities supplies to Coal Power Plant
Exchange
Facilities
CPP Project
2 x 250 t/h CFB Boilers
3 x STGs + 01 BPSTG (60Hz)
1 x 50 ~ 60 MW (50 Hz)
Balance of Plants (BOP)
Limestone
(Local Source)
Steam supply to existing complex
Sand
(Local Source)
Power supply to
existing complex
(60 Hz)
Power Export to National Grid
(on 50 Hz)
Effluent (Storm water / Cooling tower blow down)
FFBL Complex (350 Acres)

5. POWER PLANT CLASSIFICATIONS
There are 3 major classes of power plant:-
Sub-critical (upto 220 bara and upto 600 o C)
Super-critical ( bara and o C)
Ultra super critical ( bara and o C)

6. Types of Coal Based boiler technology
Coal fired Boilers
Stoker Fired Boilers
Spreader Stokers
Travelling Grate
Pulverized Coal Boilers
Fluidized Bed Boilers
Bubbling Fluidized Bed
Circulating Fluidized Bed
Pressurized Fluidized Bed

7. FLUIDIZATION BEDS COMPARISON
Application in boilers
Stoker fired
Bubbling Bed
Circulating fluidized
Pulverized coal fired
Mean particle size (mm)
<300
0.03-3
Primary air velocity (m/sec)
1-3
4-6
15-30
Solids motion
Static
Up and down
Mostly up some down Up
Overall Voidage
Agglomeration
Considerable
Some No

8. BOILER TECHNOLOGY COMPARISON
Parameter
Pulverized Coal (PC) Boiler
Circulating Fluidized Bed (CFB) Boiler
Technology Description
Coal is grinded to fine powder size before burning i.e. (<0.07 mm).
Coal is only crushed to (< 10 mm) before burning.
Fuel Flexibility
Limited and is designed for specific quality of Coal normally Bituminous or Sub-Bituminous Coals.
Wide range of Coal and Solid fuels can be burnt including:
Bituminous to Lignite (Thar Coal)
De SOx
Separate Flue Gas Desulfurization (FGD) is required for coals (S > 0.7%)
No need for separate FGD. SOx removal is carried out inside boiler by injecting limestone
De NOx
Selective Catalytic reduction (SCR) is required.
No issue, thanks for lower furnace temperature
Furnace Temperature
High temperature i.e oC.
Medium temperature i.e oC.

9. Selection of CFB boiler
Fuel flexibility
In-situ sulfur removal by using locally available limestone.
Low furnace temperature i.e. very low NOx generation.
Safe operation as compared to PC boiler.

10. Design Specifications For CPP
Description
Number of Boilers 2
Type of boiler
Single drum, Circulating Fluidized Bed Combustion Boiler
Sub-critical
Draft system
Balanced Draft
Type of Circulation
Natural Circulation
Design Capacity for each boiler
250 MeT/hr
Design Steam Pressure at SH outlet
92 bara
Boiler Efficiency
92%

11. Main Equipment's for each Boiler (2 x 250 Met/hr)
Coal, Limestone & Sand Bunkers
Main fluidized furnace with cyclones and loop seals
Fans (Primary, Secondary & ID)
Super-heaters & Economizer
Air Pre-heaters
Bag house filter
Bed Ash Discharge system
Continuous and Intermittent blow down vessels
BFW System

12. Coal Specification for CPP Project
Coal Range
Characteristics of Coals
Min
Max
Design
South Africa
Indonesia
Australia
Heating Values (at 25 °C)
LHV
kcal/kg
3,105
6,927
5,921
5,827
5,703
Volatile Matter
% ar
18.5 40
38.68 24 25
Ultimate Analysis
Total Moisture 6 26 11
8.7
10.8
Ash 3 27
11.18 14
15.9
Carbon 19 60
61.09
63.91
61.66
Hydrogen
2.0
7.0
5.09
3.65
3.83
Nitrogen
0.5
2.1
1.01
1.6
1.27
Chlorine
0.2
0.09
0.03
Sulfur
4.0
0.90
0.9
0.94
0.45
Provision to utilize local coal after mixing with imported coal

13. Consumptions for CFB Boiler
Major Boiler Consumptions
Design Coal (LHV5921 Kcal/Kg)
Per boiler at BMCR
Design Coal
Annual (330 days) per boiler at BMCR
Coal consumption
31.7 MeT/hr
502,128
Limestone consumption
1.5 MetT/hr
23,760
Sand
62 MetT (Start Up only) -
Fly ash generation
3.6 MeT/hr
57,024
Bottom ash generation
1.5 MeT/hr

15. Process Description of furnace and cyclone

16. Environmental Mitigation Measures
Selection of CFB boiler technology
Sufur (present in coal) capture inside the furnace by crushed limestone injection
Separate Bag house filter for each boiler to control Particulate Matter
Less ash generation when burning imported coals and ash recycle options to cement / brick manufacturing.
Dust suppression system
Separate Continuous Emission Monitoring System (CEMS) for each boiler.

17. Guaranteed (Design Coal) Particulate Matter(PM)
EMISSIONS GuARANTEE
Parameters
Units
Guaranteed (Design Coal)
WBG/NEQS Limits
NOx
mg/Nm3
at 6 % dry O2
370
510
SOx do
400
1500
Particulate Matter(PM) 30 50 CO
100
800
In case of use of high ash or high sulfur (4%), emissions will still within the limits.

18. CEMS
In addition to monitoring by lab, each boiler will have dedicated CEMS at flue gas duct to monitor the following:-
NOx
SOx PM CO
Temperature
CO2

19. Operation below Ash fusion temperature Higher combustion efficiency
Conclusion
CFB Boiler
Fuel flexibility
High Turndown
Operation below Ash fusion temperature
In-situ SOx Control
Low NOx Emissions
Higher combustion efficiency

20. QUESTIONS

21. THANK YOU