how boiler management solutions can improve the bottom lineb-dig.iie.org.mx/bibdig2/p11-0252/track...

© ABB Group PSP-PRU / ma Slide 1

PowerGen Europe, Amsterdam 2010-06-08Marc Antoine, Mehmet Mercangoez, Tarun Mathur

How boiler management solutions can improve the bottom line


ContentsIntroduction

Startup

Combustion

Mills

Boiler/Turbine control

Advanced unit control

Load Scheduling

Monitoring & Maintenance

Combustion instruments

Conclusions


Flue Gas Desulphurization (FGD)

Electrostatic Precipitator ESP

Unit Control(Boiler/Turbine)

Mill Pulverizer control

Boiler StartupOptimization

Continuous Emission Monitoring (CEMS)

CombustionOptimization

Coal Flow Monitoring

Carbon in Ash Monitoring

Flame Scanners

Sootblowing Advisory

Burner Mgmt Systems

Boiler Life Monitoring

Sub-systems in and around the boilerBoiler PerformanceMonitoring Load Scheduling

Selective Catalytic Reduction (SCR)


Boiler Management Systems Coordinated solutions across different sub-systems

Utility boilers are complex systems, frequently with more than 50 actuators involved in a sub-system like e.g. combustion control

Large flexibility for operators, but the basic automation system typically does not help them much with these extra degrees of freedom

Multivariable Model Predictive Control (MPC) was designed to solve these types of problems

MPC delivers superior performance over traditional single-input single-output control strategies

System-approach around the boiler:

Boiler Management Systems (BMS) consist of Instrumentation, Control and Optimization solutions, coordinated, in and around the boiler

Common platform for integration and deployment of Advanced Process Control (APC) solutions

The added value of a BMS is greater than the sum of the individual standalone solutions

Motivation (e.g. for a typical 600MW plant in USA):

0.5% heat rate reduction ~1 M$/year

10% annual NOx reduction ~2.5 M$/year

Avoiding 1 week outage ~5 M$/year


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l

StartupCombustion Mills Sootblowing SCRFGD

Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am

BurnerMgmt Mill Ctrl

FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC

CLC (Closed Loop Control), OLC (Open Loop Control), R/W (Read/Write)

CLC

Connectivity

Carbon In Ash(CIA) Flame Scanners Coal Flow

Monitor CEMS

Asset MgmtPerformanceMonitoring

ProcessInstruments (p, T,…)

Dyn

amic

O

ptim

izer Load

Scheduling

Operation

Boiler Management Systems – functional structure


optimizedvalues

controlledvalues

processvalues

boilermodel

Optimizer

Optimization goals and constraints

optimizedsetpoints

IterationsIterations

cost function= Minimum !

real boiler

MPC with cyclic tracking of the real process

MPC – general structure


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC


CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation

Boiler Management Systems


Boiler startup optimization

Features:

Non-linear, Model Predictive Control (NMPC)

The boiler model can be identified using measured data during startup phase

Parallel calculation of setpoints for fuel, superheater and reheater steam temperature and pressureExplicit consideration of the thermal stress of thick-walled components (controlling temperature differences)

Benefits:

Shorter startup time reduces fuel consumption

Faster load response to load dispatcher, better position for energy trading

Possibility for earlier warm-up of steam turbine and grid synchronization


Traditional startup procedure (dotted lines): Conservative startup to stay within design limits

Optimized startup:Exploitation of design limits for more efficient process control

Based on process model

Predictive coordination of multiple variables

Online optimization in real-time

Technology: NMPC(Nonlinear Model Predictive Control)

Typical 10 to 20% savings possible

Traditional vs. BoilerMax

unusedpotential

Savings

design limits

Fuel flow

HP-Bypass position

LS-Temperature

dT thickwalled component

Boiler startup optimization – achieved benefits


Boiler startup optimization – achieved benefits


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC


CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation



Combustion Optimization is an APC application that automates many combustion control actuators that are normally controlled manuallyThe primary objective of COS is to improve heat rate and lower emissionsCOS works with base DCS controls

Boiler master still manipulates air and fuelPressure and MW control does not change

COS works with many actuators not tied to feedback in the DCS and also biases DCS PID setpointsAuxiliary Air Dampers

Level biasesFurnace biases

Over Fire Air Dampers (OFAD)Overall demandFurnace bias

Constraints:NOx – maximum constraint, main objectiveOpacity – maximum constraint, noisy value, need filtering and non-aggressive tuningO2 imbalance – delta O2 between furnaces, controlled with furnace biases on Aux Air and OFADActuator constraints – must keep base DCS loops in operating range, usually below a max output

Spray valves and Dampers

Wind Box ΔP setpoint bias

O2 setpoint bias

Tilts demands

Mill Elevation biases

Combustion optimization


Combustion optimization – NOx Reduction (step 1)

Aux Air bias -5 to 20%

OFAD 0 to 100%

WindBox ΔP -1 to 0.5

OFAD and Aux Air reach limitsAll actuators push

back toward their soft targets

As limit is lowered,

more actuators help out:


East Tilt -5 to 15West Tilt -5 to 15Mill Elev -10 to 10

Tilts and Elevation increase effort after air variables reach limits

As limit is lowered,

more actuators help out:

Combustion optimization – NOx Reduction (step 2)


Combustion optimization – O2 balancing, Heat RatePerfect O2 balancing while controlling NOx and minimizing reheat spray

Aux Air Bias

OFAD Bias

O2 A & B


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC


CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation



Coal Mills – advanced vs. classic control

Steam P

Master Controllers

MW

Setpoints

Individual coal mill control: Coal feeder reference maintain primary air flow and dynamic classifier speed in case it is available

Parallel arrangement maintain mill outlet temperature, with hot and cold air damper positions

Coordinated pulverizer control:MPC controller generates the individual pulverizer references to satisfy total pulverized fuel demand

MPC controller monitors pulverizer statesand adjusts the coal feed setpointsaccordingly

Better pulverizers take higher loads

Possibility to keep pulverizer pressure drop under control by shifting the load temporarily from one pulverizer to another with lower pressure drop

Coal Demand

Coal Demand / 4

MPC

Mill Controller

CIA


Coal Mills - optimization

Objective

Include Mill ΔP as a constraint

30s cycle

300s horizon

Objective

Maximize hot air use or mill capacity

30s cycle

600s horizonObjective

Improve mill response time or PF fineness

10s cycle

100s horizon


Coal Mills - model

Grinding:

Assuming a particle size classification with 3 bins: Raw / Reject / Pulverized (PF)

Maximum PF size 74 microns, fuel quality the percentage of particles in this bin (e.g. 75%)

Model equations describe the grinding rate from raw feed to rejects and from rejects to PF calculate the particle size distribution on the grinding table

Drying:

Energy balance around pulverizer PF temperature

Enables feed-forward adjustment of the primary air temperature

Correcting the model predictions by using actual classifier temperature estimates raw moisture content

Separation:

Momentum balance suspension and carryover of coal particles with primary air

Impact of classifier speed on reject rate is determined by analyzing the corresponding changes in mill motor power consumption and the mill pressure drop

Model is capable of representing both the passive (due to primary air lift) and active (due to centrifugal effects) particle size separation

Estimates unmeasured coal mill outputs e.g. PF flow and fineness and PF stored inside the mill


Coal Mills - model accuracy


Coal Mill Optimization – MPC vs. classic PID

MPC controller, compared to classic PID controls:

Capability to control pulverized fuel quality (fineness), e.g. achieving the setpoint of 75% coal fineness of 74 microns (or less)

Tighter control of mill outlet temperature

Faster control response (2x) for load changes (e.g. 70% load increase)


Coal Mill Optimization – benefits

Improved availability

Optimal allocation of the coal load among the available pulverizers

Ride through transient disturbances e.g. mill inlet chocking or increased pressure drop instead of waiting for the troubled pulverizer to fall into runback mode

Allows mill pressure drop to become a closed loop controlled variable to avoid cascaded mill trips

Increased efficiency

Maintain adequate fuel fineness and optimize primary air temperature maximize pulverizer drying capacity or maximize combustion efficiency

Improved plant agility

Example (also practiced by experienced power plant operators): the MPC mill controller can accurately determine the stored pulverized fuel in the mill holdup

calculate a reduction in the classifier revolutions temporary but immediate boost in pulverized fuel output in a completely automated way


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC


CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation



Boiler/Turbine coordinated control

Automatic(Dispatcher adjusts unit load)

Automatic(Controls MWe + TP)

Automatic(Controls MWe -TP)

Coordinated (Auto)

Manual(Operator adjusts unit load)

Automatic(Controls MWe + TP)

Automatic(Controls MWe - TP)

Coordinated (Manual)

ManualManual(Operator adjusts unit load)

Automatic(Controls TP)

Boiler Follow

ManualAutomatic(Controls TP)

Manual(Operator adjusts unit load)

Turbine Follow

ManualManualManualManual

Unit MasterTurbine Master Boiler MasterModes

Benefits:

Operating flexibility for base load or ramp loading

Coordination with other sub-loops for safe operation

Feed-forward techniques to provide rapid response for unit load changes

Adaptive tuning of model parameters to adjust for different load sensitivities

Improved turbine life and reduced turbine maintenance costs in variable pressure operation through the relatively stable turbine inlet temperature


0

6

12

15

18

40 70 100

turbine valve throttling in %

load in %

MODAN

MODAKOND(ABB-CONDSTOP)

LS

turbine loadcontroller

grid-frequencydeviation

pressurecontroller

fuelcontroller

turbine valveposition controller

remote dispatcher setpoint

p k·Δf–+

– +

+

–

+

–

dynamicMW model

PEI

P–

GRH

Boiler following mode 4 3 2 1

dynamicpressuremodel

dynamicfeed-forward

control boiler

load setpoint

dynamicfeed-forward

control turbine

Advanced Unit Control - basic

Primary grid frequency control for balance between power generation and consumption

Grid secondary control (load-frequency control by load dispatcher) to regulate agreed load exchange between interconnected power suppliers


0

6

12

15

18

40 70 100

turbine valve throttling in %

load in %

MODAN

MODAKOND(ABB-CONDSTOP)

LS

turbine loadcontroller

grid-frequencydeviation

pressurecontroller

fuelcontroller

turbine valveposition controller

remote dispatcher setpoint

p k·Δf–+

– +

+

–

+

–

dynamicMW model

PEI

P–

GRH

CONDSTOP

Boiler following mode 4 3 2 1

dynamicpressuremodel

dynamicfeed-forward

control boiler

load setpoint

dynamicfeed-forward

control turbine

Dynamicfeed-forward

control

Advanced Unit Control – with CONDSTOP

Improved plant efficiency for primary frequency control through reduced throttling of the turbine control valves

Reduced control tasks allow for smoother operation of main components such as pulverizers, FD- and ID-fans, reducing plant operation costs


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC


CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation



FGD Control and Optimization

Major cost to be minimized in FGD operation

Raw material cost of limestone

Power consumption of recirculation pumps for limestone slurry, and fans for oxidation air


SCR / SNCR Control and OptimizationCombined with Combustion Optimization (COS)

MPC

O2 set point bias

Windbox ∆P setpoint bias

Auxilliary Air bias

Mill Feeder bias

OFA

Burner Tilt

Unit Load

Dem

and

Outlet NOx

Stack Opacity

Reheat Spray demand

O2 in balance

Feed Forward Variable

FG Temp at SNCR injection level

Reagent flow rate Reagent cost

SNCR with COS

MPC

O2 set point bias

Windbox ∆P set point bias

Auxiliary Air bias

Mill Feeder bias

OFA

Burner Tilt

Unit Load

Dem

andOutlet Nox (SCR outlet)

Stack Opacity

Reheat Spray demand

O2 in balance

FG Temp at inlet ofSCR

Reagent flow rateReagent cost

Economizer bypass flow

Better flexibility for NOx removal.Some degree of control over disturbance variable, Flue Gas TemperatureCIA used as additional feed-forward variable, or as bounded variable in MPC

SCR with COSNOx at inlet of SCR

CIA

Meas.

CIA

Meas.


SCR / SNCR Control and OptimizationCombined with Combustion Optimization (COS)

SCR reactions are generally effective in flue gas temperature range of 340 - 400degC but temperature imbalances of up to 150degC are common

Above the specified temperature range for the reduction reaction, NH3 is oxidized to NOx

At low temperature there is a possibility of lower rate of reaction leading to Ammonia Slip

The MPC model estimates internal states and uses them for control

e.g. Ammonia must be deposited on the catalyst before the reaction can take place

The observer estimates ammonia deposition and the controller uses the estimated deposition to reduce ammonia slip

System approach:

Combine COS and SNCR/SCR optimization due to obvious interaction between the two in terms of temperature

e.g. if the CIA hits the upper bound, it is better to have more NOx removal in the SCR than in the combustion process itself, in order to keep CIA within desired bounds


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC


CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation



Load Scheduling Optimization

Determine the optimal load schedule for multiple units operating under constraints

Based on demand profile (e.g. for power and heat)

Time horizons: hours to days

Constraints:

Generated power, auxiliary consumption

Capacity (e.g. power, heat)

Minimum standstill period, minimum operating time, load gradient limitation, hot start/cold start

Limitations on operating time, storage, startup frequency


Load Scheduling Optimization Meeting Steam and Power Demand


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC

CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation


Benefits:

Early detection of deviations and decision support for pro-active maintenance.

Verification of performance improvements in plant processes.

Detection of faults, which may lead to shortened service life.

Documented evidence of operational use of equipment.

Long-term maintenance planning and potential for reduced inspection frequency.

Certified report generation of performance, service life and emissions, for authorities.


Mon

itorin

g &

M

aint

enan

ceC

ontr

olI/O

de

vice

sO

ptim

izat

ion

Blo

ck C

trl

Gro

up C

trl

Loop

Ctr

l


Block Ctrl Program

BoilerMaster

Air /Flue Gas

FWSystem

CombustionCtrl

Aux

Ste

am


FD F

an

Mill

1

Dru

m L

evel

ID F

an

FW P

ump

Con

dens

ateTu

rbin

e C

trl

Bur

ner …

Bur

ner 1

Mill

…

Closed Loop Ctrl

Structure Program

Setpoint Ctrl

Unit Load

AdvancedUnit Ctrl

FWCtrl

Air Ctrl

FuelCtrl

Air

1…n

FW /

Spra

ys

Feed

ers

1…n

Turn

ing

Gea

r

Evac

uatio

n

DeNOx(SCR)

TurbineMaster

Stea

m T

& p

HP

Byp

ass

DeSOx(FGD)

CommonSystem

LifetimeMonitoring

EmissionMonitoring

ConditionMonitoring

R /

W

OLC


CLC

Connectivity


Monitor CEMS



Dyn

amic

O

ptim

izer Load

Scheduling

Operation



FeaturesOn-line Pulverized Flow (PF) measurements of:

Absolute PF velocityBurner PF splitRelative PF loading (concentration)Mass flow rate, computed for each line, from split, but requires external total mass input (mill feed rate or similar)

BenefitsMeasurement across total cross sectionNon-intrusive, low maintenanceVirtually unaffected by ropingTolerant to poor upstream flow conditionsNo need for on-site calibration, unaffected by changes in coal type and moisture content Saves PF sampling cost

Coal Flow - monitoring


FeaturesOnline microwave measurement of unburnt coal in boiler backpassHigh accuracyLow maintenanceIndependent of coal quality and unit load

BenefitsDetection of arising problems with

BurnersAir adjustment / distributionMills

Improves ash qualityFeedback or feedf-orward signal for APC solutions

Carbon In Ash - monitoring


FeaturesDetects individual flame presenceProvides flame quality indexContinuous data to any plant control system via standard interfacesIndividual flame raw signal for flame analysis and burner diagnosis

BenefitsIsolates individual burners as specific contributors to emissioncreationImprove safety, reliability, reduce downtimeBasis for Combustion Optimization and Emission reduction

Flame Scanners


Conclusions

Boiler Management Systems (BMS) consist of different layers of instrumentation, control and optimization solutions

System-approach Integrated coordinated control and optimization solutions between different boiler sub-systems

Multivariable Model Predictive Control (MPC) as underlying technology

Benefits:

Faster ramping rates

Reduced emissions

Improved plant stability and availability

Higher plant efficiency


Reduces Variance pushes to Limit

5

4

3

2

1

0500° 510° 520° 530° 540° 550°

6

% S

ampl

es/ D

egC

actual constraintbefore MPC

Reduce

VarianceShift

Target

MPC improves Control & Performance


Coal Mill Model

Physical model

3 states particle sizes

1 state coal moisture

1 state temperature

Simplified physical model

1 state coal holdup

1 state coal moisture

1 state temperature

Model

4 inputs: coal feed rate, PA flow, classifier rev, T set point

3 outputs: motor amps, ΔP, PF T

Note: not limited to 4 inputs (can be more).


Coal Mill Model

how boiler management solutions can improve the bottom lineb-dig.iie.org.mx/bibdig2/p11-0252/track...

Documents