Combustion@Max Boilers@Max · Combustion@Max & Boiler@Max 16 Introduction Benefits (approx) Benefit Numbers (Chinese market conditions) • Coal Savings 200-300,000 Euros per year

Combustion@Max & Boiler@Max 1

Combustion@Max

&

Boilers@Max


PAST FUTURE

Y2(t)

U1(t)

Y1(t)

Y1(t)U1(t)PLANT

Y2,3(t)U2(t)

Y1(t)U1(t)Model

Y2,3(t)U2(t)

^

^

U2(t)

Safety

Quality

Heat rate

NOx

Pressure

BFW

Steam Valve

Ambient T

INCA MPC

Principle of MPCAmbient T

Y3(t)

FuelU3(t)


MV2

MV1

CV2

CV1

time

CV2

DV1MV2

time

CV1

MV1

time

time time

time

time

calculate a model which

minimizes the between models output

and observed output

DV1

INCA MPC

Advanced Process Control -

How to get the models


INCA MPC

Performance = f(model quality)

Your feed forward performance will not be optimal…,

and a lot of feed-back action is needed to compensate for the differences!

if this is your model… and this is reality….


Prediction:Predict the future of CV’s based on past and assumed future inputs and the measured CV’s

Receding horizon [samples]

+5

5.1

5.2MV

t-400 t-200 t t+200 t+400 t+600

469.2

469.4CV

Past horizon Prediction (or future) horizon

HuPast

Ideal

TuFuture

prediction

ym(t)

yp(t)

d(t)=yp(t)-ym(t) yprediction

Current time instant t

INCA MPC

Basic MPC concepts prediction


TECHNOLOGY

INTERFACES

Engine

Pre CalcPre CalcPost CalcPost Calc

DCS Network

DCS OPC Server

Engineering Station

OPC Server

Exchange

Pre Calc

Engine

Post Calc

View

Scheduler

Test

Discovery Configurator Test


INCA MPC

Integration of INCA in Automation

Systems: e.g. via PID


• Dynamic process model-based predictive control technology based on INCA MPC

• Process know-how from IPCOS [and OPSYS] engineers

• Proven technology (references in China: Beihai, Datang, Shanghai Power, QinZhou, National power)

Introduction

What is it?


Introduction

MPC vs. PID

• MPC can offer significantly better control than PID (at least a 50% improvement in regulation over PID control)

• Looks at boiler efficiency (BE)

• Cost effective to implement (payback << 12 months)

• MPC is also scalable

• Integrated in DCS (as with PID).


Introduction

MPC Process

• Phase One – Audit

• Phase Two – Data Collection and Model Design

• Phase Three – Implementation and Commissioning

• Phase Three – Maintenance and Support


introduction

Benefits (1)

• 0.3 – 0.7% improvement in Boiler efficiency

• Coal Savings

• Better Temperature control of furnace exit gas temperatures

• 5-10% NOx reduction

• Reduced Nox going into your Nox reduction system (load)

• Possible extension of catalyst life

• Possible reduction of ammonia or urea


Introduction

Benefits (2)

• Better control of Carbon in Ash (CIA)

– Use CIA as a driver to make advantage of ash

– If your ash is dumped, perhaps you will be able to sell it

– If you need quality consistency – this can give it to you


Introduction

Benefits (3)

• Better knowledge of boiler

– Helps understand boiler operation due to the amount of mathematical models available

– Helps understand what is really happening inside the boiler

– Which controls are actually helping your boiler

– Maintain the controls which create the better value


Introduction

Benefits (4)

• Automatic Operation is tighter

– As if your best operator is on the job 24 hours a day, every day.

– Like Auto-Pilot on an airplane

– Ensures consistency in operation

– All priority functions can be monitored

• Which operator is taking what in and out of service

• Which operator is getting the best from the system


Introduction

Benefits (approx)

Benefit Numbers (Chinese market conditions)

• Coal Savings 200-300,000 Euros per year

• Nox reduction 20-30,000 Euros per year

• Boiler Knowledge 20-100,000 Euros per year

• Better Operation 20-100,000 Euros per year

• Carbon in Ash 20 - 100,000 Euros per year

• Better control of Temperatures 20 – 50,000 Euros per year


Introduction

Power plant Layoutfurnace exit

gas

temperature

selective non

catalytic

reduction

Selective

catalytic

reduction

electrostatic

precipitator

continuous

emission

monitoring

system

flue-gas

desulphurisation

Relative

Accuracy Test

Audits


Confidential

Introduction

What does the APC Control?

18


Introduction

Datang Power

19

• One of the Big 5 Generating Utilities

• Over One Hundred Coal Fired Power plants in China

• One new power plant comes online every month.


Introduction

Unit Description

20

• 330MW

• CE T-Fired

• 5 Mills

• Lignite Coal

• Built in 2006

• Started Operation in

2007


Introduction

Project Description

21

• APC Scope：185MW（without oil）to full load

• APC Mode：Run-time Optimize by bias adjustment to DCS

• Target: Improved Boiler Efficiency by 0.3% above the base and keeping the steam quality


Results

Estimated Project Benefits

(coal savings alone)

22

• BE improvements above 0.3%，

• Calculated on 330MW unit: The Coal Consumption will be Reduced above 1.1g/kw

• If load rate 80％ per year，and APC operating 5500h,

• Coal Saving by year ＝ 330WM * 80% * 5.5kh * 1.1g/kw = 1600t

• Local Coal Price 80 Euros/t，Yearly benefit will be: 80 * 1600t ≈ 128,000 Euros


APC System

CONTROL MATRIX• The controller has the following sections:

• Fan Balancing:

– PAF (Prim air),

– IDF (induced),

– FDF (forced)

• Steam system: Gas Damper, Fsh/rh, Psh/rh, Tsh/rh,

• Mill Outlet Temperature: (hot – cold Prim Air)

• Carry-on air

• Secondary Air (-> NOx control)

• Tertiary Air (-> NOx control

• Oxygen


APC System

CONTROL MATRIXSafety Limits: 0 – 99

Furnace draft: zone

Total air flow: zone

Main Steam Temperature: zone and ideal

Reheat Temperature: zone and ideal

Carry On Damper Bias Sum: zone and ideal

Quality Limits: 100 – 199

CO: zone

Oxygen: zone and ideal

Economic Limits: 200 – 299

BE_q2: ideal, minimize

NOx: ideal, minimize



SH 2nd Spray Inlet Temperature: zone + ideal, maximize (minimize water flow)

SH 1st Spray Outlet Temperature: zone + ideal, minimize (maximize water flow)

PAF Balancing

FDF Balancing

IDF Balancing


APC System

CONTROL MATRIXMV tagname

1 APC O2 Bias

2 APC Mill A Outlet Temp SP

3 APC Mill B Outlet Temp SP

4 APC Mill C Outlet Temp SP

5 APC Mill D Outlet Temp SP

6 APC Mill A1 Carry-on Damper Bias

7 APC Mill A2 Carry-on Damper Bias

8 APC Mill B1 Carry-on Damper Bias

9 APC Mill B2 Carry-on Damper Bias

10 APC Mill C1 Carry-on Damper Bias

11 APC Mill C2 Carry-on Damper Bias

12 APC Mill D1 Carry-on Damper Bias

13 APC Mill D2 Carry-on Damper Bias

14 APC Secondary Air A12 Damper Bias

15 APC Secondary Air A34 Damper Bias

16 APC Secondary Air B12 Damper Bias

17 APC Secondary Air B34 Damper Bias

18 APC Secondary Air C12 Damper Bias

19 APC Secondary Air C34 Damper Bias

20 APC Secondary Air D12 Damper Bias

21 APC Secondary Air D34 Damper Bias

22 APC Tertiary Air A12 Damper Bias

23 APC Tertiary Air A34 Damper Bias

24 APC Tertiary Air B12 Damper Bias

25 APC Tertiary Air B34 Damper Bias

26 APC Tertiary Air C12 Damper Bias

27 APC Tertiary Air C34 Damper Bias

28 APC Tertiary Air D12 Damper Bias

29 APC Tertiary Air D34 Damper Bias

30 APC Gas Damper Bias

31 APC FSH Temp Bias

32 APC PSH Temp Bias

33 APC PAF Balance Bias

34 APC FDF Balance Bias

35 APC IDF Balance Bias

DV tagname

1 UNIT_LOAD

2 MS_PRESS

2 SH 1st Spray Inlet Temperature

3 SH 2nd Spray Inlet Temperature

4 SH_1SPRAY Valve

5 SH_2SPRAY_Valve

6 RH InletTemperature

7 RH_SPRAY_FLOW

8 INLET_AIR_TEMP

9 HeatID(Total Fuel/Total Air)

10 Gas Temp

11 BE

CV tagname

1 BE_q2 (dry gas losses) %

2 BE_q3 (Chemical, e.g. CO) %

3 BE_q4 (Carbon in Ash) %

4 Corr_Nox mg/Nm3

5 Corr_CO

6 MS_Temp C

7 SH 2nd Spray Inlet Temperature C

8

SH 1st Spray Outlet

Temperature C

9 RH_Temp C

10 O2 %

11 Total Air Flow Pa

12 O2_Diff %

13 Furnace Draft %

14 PAF A/B Current Diff A

15 PAF A/B Outlet Press Diff kPa

16 FDF A/B Current Diff A

17 FDF A/B Outlet Press Diff kPa

18 FDF A/B Outlet Flow Diff t/h

19 IDF A/B Current Diff A

20 IDF A/B Inlet Press Diff kPa

21 CA BIAS SUM


APC System

CONTROL MATRIX

干烟气损失

飞灰含碳

炉膛出口平均氧量

大风箱与炉膛差压

总风量

炉膛

(A/B

)烟温偏差

引风机

(A/B

)电流差

引风机

(A/B

)入口压差

送风机

(A/B

)电流差

送风机

(A/B

)风量差

送风机

(A/B

)出口压差

过热器温度

再热器温度

过热器区间

1金属温度

过热器区间

2金属温度

过热器区间

3金属温度

过热器区间

4金属温度

再热器区间

1金属温度

再热器区间

2金属温度

氧量偏置 X X X X X X X X X X X

给煤机(A/B/C/D/E)偏置 X X X X X X X X X X

二次风(AA/AB/BB/DD/DE)偏置 X X X X X X X X X X X X

二次风CC偏置 X X X X

周界风组(A/B/C/D/E)偏置 X X X X X X

过燃风EF层偏置 X X X X X X X X X X X X X X

过燃风F层偏置 X X X X X X X X X X X X X X

引风机(A/B)平衡偏置 X X

送风机(A/B)平衡偏置 X X X

主蒸汽流量 X X X X X X X X X X X

过热器减温水流量 X

再热器减温水流量 X

大气温度 X

煤风比 X X X X X X

锅炉效率

机组负荷指令 X X

M

V

(

可

控

量

)

D

V

(

干

扰

量

)


APC System

DCS Console GUI


APC System

APC Alarm Page


Results

Additional Benefits

• Better control of Boiler (Efficiency)

• Better control of Steam quality (Pres and Temp)

• Better understanding of the operation of plant

• Better continuous Auto – Control

• Reduced Emissions

• Reduced Unburned Carbon in Ash


Results

Acceptance Tests @330MW

330WM APC Off APC On

DiffStart2008-05-30

13:302008-05-30

17:00

End2008-05-30

15:302008-05-30

19:59

LOAD MW 328.79 328.89

MS_FLOW T/H 952.74 945.93

BE_Q2 (Dry gas loss) % 6.01 5.66 0.35

BE % 92.95 93.32 0.37


Results

Acceptance Tests @270MW

270WM APC Off APC On

DiffStart2008-06-05

08:102008-06-05

10:30

End2008-06-05

09:402008-06-05

00:30

LOAD MW 269.84 269.75

MS_FLOW T/H 776.06 791.94

BE_Q2 (Dry gas loss)

% 5.10 4.81 0.30

BE % 93.89 94.21 0.32


Results

Acceptance Tests


Results

Total Solution

• Boiler Efficiency improved at least 0.5% (ARC +APC)

– Better PID’s

– Better Logic

– Better Operation Curves

• Aux Power saving above 0.15%

• Steam Quality closed near design value 2~3C

• 0.1% BE increase = 1750 Ton/Year (330MW unit)

• 0.5% BE increase = 8750Ton/Year (330MW unit)


FLUE GAS CONDITIONING

Challenges

• Maintaining emission levels at specifications (good enough?)

• Stabilizing process conditions having a positive effect on catalyst aging, thermal stress,…..

• Take care of disturbances (boiler load, Sulphur conditions, ambient air conditions, steam conditions,..)

• Operate at maximum conversion/efficiency (if measured).

Documents

Combustion@Max Boilers@Max · Combustion@Max & Boiler@Max 16 Introduction Benefits (approx) Benefit Numbers (Chinese market conditions) • Coal Savings 200-300,000 Euros per year