coal fired ge tobin

7/27/2019 Coal Fired GE Tobin

1/22

CombustionOptimization for

Coal-Fired Boilers

2nd U.S.-China NOx WorkshopDalian, China

August 2005

James TobinNeil Widmer

GE Energy


2/22

The problem


3/22

3GE Energy

August 2005

Poor combustion result in many

performance issues.

Reduced

Througput (Load)

High Metal

Temperatures

Increased FEGT(Furnace Exit Gas Temperature)

Reduced

Efficiency

~Coal

Supply

CoalCrushe

r

Mill

CoalSilos

Boiler

AirHeater

Stack

IDFan

FDFan

Turbine Generator

Local Fouling

Increased

Steam Spray

Local Slagging

Local Hot Spots

Increased

Excess O2

High COHigh CO

Combustion profile as monitored

by Spatial Sensors

Economizer

O2 Imbalance

Local Corrosion

High Carbon in

Ash, eg. LOI(Loss on Ignition)

High NOx


4/22

4GE Energy

August 2005

The major lost opportunities result from

poor combustion.Fleet-wide lost opportunity

cost can be over $80 MMper year.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Boiler Fleet

AnnualLossOpportu

nityContribu

tions

Condensate System

Opacity

Controls Chemistry

Seasonal Derate

Feedwater System

Slag & Ash Removal

PRB Derate

Air Supply

Fuel Quality

Mill/Feeders

Turbine

Tube Leaks

Contributing Factors:


5/22

5GE Energy

August 2005

Improved burner operation drives

performance gains.

Fuel Savings

Comfort

Zone

Initial A/FInitial A/F

FEGT

ImprovedImprovedA/FA/F

High CO Burners LimitPerformance

Emissions Credits

Availability & Peak Power

Output (Throughput)


6/22

Solutions


7/22

7GE Energy

August 2005

Zonal combustion control system

Combustion (O2/CO)Monitors

Output

NOx

AvailabilityBurnerAirflow

Controls

CombustionTuningControls

Efficiency

CombustionDiagnostic

ZonalFuel and AirOptimization

BurnerAdjustments

1

2

3

object

BurnerCoal FlowControls


8/22

8GE Energy

August 2005

Combustion

Sensors

CombustionTuning Model

Burner AirflowControls

Coal Flow

Sensors

Coal FlowDampers

Components

Zonal Combustion

Controls


9/22

9GE Energy

August 2005


how fuel & air controls work together.Zonal CO Trim - fine controlsfor combustion balancing :

> Trim furnace zonal air/fuelratios based on sensor grid

Balance CO

Reduce hot spots

Reduce delayedcombustion

Maintain burner flame Reduce LOI

Reduce excess O2

Zonal Fuel Trim - coarsecontrols for combustionshaping :

> Optimize wall-burner firing

Reduce impingement

> Reshape tangential fireball

Centered and round

> Tune furnace fueldistribution

Balance economizer O2 Divert heat loading from

peak FEGT & slag regions


10/22

10GE Energy

August 2005

Fuel control can reduce temperature

and CO zones the precursors to slag.AfterBefore

CO Profile

Max = 2088 Max = 2023

Gas Temp. Profile


11/22

11GE Energy

August 2005

Automatic Fuel Trim controls are

successful at tightening distribution.

-25%-20%

-15%

-10%

-5%

0%

5%

10%

15%

Burner CoalFlow Bias

As-Found Manual Automatic

Coal Distribution

Burner C1

Burner C2

Burner C3

Burner C4

Burner C5

First Demonstration August 2003


12/22

12GE Energy

August 2005

Balanced and optimized coal flow

distribution reduced peak FEGT 60F.

2375

2400

2425

2450

2475

2500

2525

FurnaceExitGas

Tempera

ture(deg.

F)

Baseline Balanced OptimizedCoal Distribution

Ash FusionPoint

PeakFEGTReduction

10MWCapa

cityIncrease


13/22

13GE Energy

August 2005

20F Peak FEGT limited boiler capacity

approximately 10MW.

2,150

2,200

2,250

2,300

2,350

2,400

2,450

2,500

2,550

2,600

2,650

2,700

220 240 260 280 300 320 340 360 380 400

Load, MWg

FurnaceExitGasTemperature,

degF

FEGT West

FEGT East

FEGT Average

Turbine Capacity

Boiler Limit


14/22

14GE Energy

August 2005

Zonal combustion monitoring system

Interface Display

Modeling

(upgrade)

Flow and

Control PanelSensor Array


15/22

15GE Energy

August 2005

Zonal combustion model-based

control system.Combustion Trim ModelMonitoring & Control Interface


16/22

16GE Energy

August 2005

Zonal combustion tuning system

demonstration.

Burner

Tuning

CombustionSensors

Boiler Model

Initial CO

Tuned CO

Tunin

e

mo

gD


17/22

17GE Energy

August 2005

0

100

200

300

400

500

600

700

800

900

1000

COLe

vel,ppm

CO#11

CO#6

CO#12

CO#7

CO#14

CO#13

CO#1

CO#9

CO#8

CO#10

CO#4

CO#15

CO#5

CO#2

CO#3

Combustion Sensors

Initial Tuned

0

0.5

1

1.5

2

2.5

3

3.5

Fly-As

hLOI,%

West Middle East

Flue Gas Duct

Initial Tuned

Systematic tuning balanced CO and

fly-ash LOI synergistic with Hg control.


18/22

18GE Energy

August 2005


features:> Faster tuning experience

> One system for managing Zonal combustion

> Improves quality through systematic methods

> Advises burner adjustments> Stores preferred burner setting by operating

mode> Diagnoses combustion performance


19/22

Benefits


20/22

20GE Energy

August 2005

Combustion Optimization Case Study

Sunflower Electric 380 MW BoilerScope:> GE coal flow monitors & control

> GE combustion sensors> GE boiler tuning services

> GE control software

System Benefits:> Reduced peak FEGT 60F

Eliminated barrier to increasingoutput 10 MW worth $1M/yr

> Reduced high CO and temperaturezones

Avoid future slag outage 1weeks worth ~ $2.5M/yr

> Reduced NOx and Heat Rate

Furnace Combustion

Balancing

Burner Fuel/Air Flow

Sensors & Auto-Control

Coal

Flow

Sensor

Coal

Damper

Furnace

Combustion

Sensor Arrays

COSensor

Burner Air

Control


21/22

21GE Energy

August 2005

Zonal combustion controls benefits:

9Reduce average and peak FEGT

9Reduce fuel rich (CO) zones

9Reduce corrosion

9Reduce slagging

9Reduce LOI

9Reduced NOx


22/22

22GE Energy

August 2005

Good combustion provides significant

benefits.

0

500

1,0001,500

2,000

2,500

100 300 500 700 900

Boiler Load, MWe

A

nnua

lBene

fits

,k$/yr

Emissions Heat Rate

Peak Power Availability

Improvements :

> Excess O2: 0.5% reduction> Emissions (NOx): 15% reduction

> Heat Rate: 0.4% improvement

> Peak Power: 2.3% increase> Availability: 1 week avoided

outage

Economic assumptions provided in notes

Economic benefits are site-specific. Your plants benefits may vary.

coal fired ge tobin

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