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18.05.2009, CCT2009 Dresden

Retrofitting study of a 350MW hard coal fired power plant with post combustion capture

-optimal integration pathways for minimizing

the energy penalty

Christoph Kümmritz, Jochen Oexmann, Alfons Kather, Christian Mehrkens (1)Gerald Kinger, Martin Burböck (2)

(2)EVN AGEVN PlatzA-2344 Maria EnzersdorfAustria

(1)Technical university Hamburg-HarburgDenickestr. 15 D-21073 HamburgGermany

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EVN: a short overview…1.5m electricity, gas, heat and watercustomers in Lower Austria

more than 3m customers in 18 countries

1.5m electricity customers in Bulgaria

700,000 electricity costumers in Macedonia

1,800MWe generation capacity (Gas, coal, hydro, wind and biomass)

124,000 km electricity network, 13,300 km gas pipelines

70 drinking/waste water plants for 10m people

Construction and operation of waste incineration plant in Moscow (Russia)

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specific CO2 emissions of power stations decreased by 16% (1998-2008)

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0,10

0,20

0,30

0,40

0,50

0,60

0,70

1998 2000 2002 2004 2006 2008 2010 zukünftig

Dur

chsc

hn. s

pez.

CO

2 Em

issi

on E

VN th

erm

. Kra

ftw

erke

Reduktion durch weitere Maßnahmen

1998 - 2008-16%

more than 32% of produced energy from renewable sources (2007/08)

minimizing power network losses energy-related advisory servicealternative fuels (ie. LNG)

CCS – bridging technology on the way to a carbon free energy production

3) increase end-use energy efficiency

1) increase in energy efficiency 2) renewable energy

development of water & wind power in EVN

CCS … Carbon Capture and Storage

CO2 emission – EVN's mitigation route

1 2 3 44) CCS technology

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Carbon Capture & Storage

Pre-Combustion(IGGC)

Oxyfuel

Post-Combustion

air

air

air

nitrogen

nitrogen

oxygen

oxygen

*) ASU=air seperation unit

ASU *)

LZA *)

hydrogen

CO2

reforming

CO2

flue gas

CO2 scrubbing

CO2

steam turbine

steam turbinegas turbine

CO2

compressorcoal, natural gas

coal, natural gas

H2

coal,gas

CO

2st

orag

e

tran

spor

t sys

tem

(i.e

.: pi

pelin

e)

CO2

compressor

CO2

compressor

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"Dürnrohr Block II"• commissioning: 1986• natural gas / coal • Output: 352 MWel

• flue gas cleaning:- SCR deNOx- desulfurization (semi-dry)- ESP filter

• fresh water cooling• Net-efficiency: (coal fire) ~42%• program for simulation: EBSILON Professional

Power station Dürnrohr

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to water treatment

flue gas cooler

blower

absorber column

desorber column

heat exchanger

solvent pumps

fluegas cooler: better absorption at lower temp.

absorber column: chemical absorption of CO2

Rich / Lean HX: heat recovery

desorber column: (+Reboiler) expel CO2 by heat

set-up of post-combustion equipment

from FGD to CO2 compressor

steam and condensate from power plant

to atmosphere

solvent: Monoethanolamine (MEA)loading: 0.5 mol CO2/mol MEACO2-quality > 99.5%

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integration of PCC equipment into the plant

generatorflue gas cleaning

absorberdesorber /reboiler

compressor

flue gas steam

CO2 CO2

cooling water

electrical energy

existing power plant

1.2. 3.

turbine

boiler

cooling water

steam (heat)

(new) PCC equipment

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heat (steam)

steam extraction form intermediate pressure turbine:• existing turbine offers possibility to extract steam (originally

planned district heating system was not realized)

boundary conditions:• allowed steam velocity max. 85m/s (turbine)

• steam pressure lowered due to reduced mass flow

• Treb. @ 3,13 bar = 135°C losses due to long pipes; lower limit for optimal operation of reboiler (2,05 bar; Treb. =125°C)

• Treb. @ 1,9 bar = 115°C desorber operated at atmopheric condition (Treb. =105°C). Specific higher heat demand but lower steam parameters needed, more steam of this parameters and velocity available

capture rates from 30% to 67% possible

integration of PCC equipment (3)

A3A4A5A6

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integration of PCC equipment (4)

for a 90% capture rate: 1) pipe from IP to LP turbine: not sufficient

amount of steam for heat demand of reboiler

2) steam before intermediate heating: need for rebuilding boiler to maintain cooling

3) steam after intermediate heating: parameters 42bar, 530 °Cneeded: ~3,5bar

HZÜ

KZÜ

2

3

IP

1

boiler

10

Reboiler

3,5 bar

MCO2 compressor

efficiency loss 10,0%specific energy demand: 0,339 kWhe /kgCO2

extra turbineand generator

… most promising variation:

drawbacks:additional turbine and generator needed, extensive reconstruction work needed.

existing plantretro-fit

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0

1

2

3

4

5

6

7

8

20 30 40 50 60 70 80 90 100

effic

ienc

y lo

ss (%

)

CO2 capture rate (%)

maximum capture rate (IP steam): 67%specific energy demand:0,309 kWhe/kg CO2

energetically optimum: 43,5%specific energy demand:0,287 kWhe/kg CO2

Results – efficiency loss

CO2 capture rate 90%:efficiency loss 10,02%, specific energy demand: 0,339 kWhe/kgCO2

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Results – specific CO2 emissions (kgCO2/MWhe)

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100

200

300

400

500

600

700

800

900

without CCS 43,5%, energeticallyoptimum

67%, max. capturerate with IP steam

90% capture rate

efficiency:42%

efficiency:38%

efficiency:35%

efficiency:32%

specific CO2 Emissions of modern combined cycle power plant

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economic effects – influence of CCS on CoE

CO2 capture rate (%)

+23%+25% +28%

+40%cost of CCS cost of CCS

specific cost of electricity without CCSspecific cost of electricity without CCSincreased cost due to reduced outputincreased cost due to reduced output

CoE … (specific) cost of electricity

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economic effects – CO2 abatement costCO2 capture rate

43,5% 67% 90%CO2 abatement cost

(EUR)47,6 46,1 47,9

(2008)

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conclusionssummary – results:

• steam from existing IP turbine: minimum reconstruction work needed• capture rates of 30 to 67% at -3 to -7% efficiency loss possible• steam from boiler after intermediate heating: additional turbine and

generator needed• capture rate of 90% at -10% efficiency loss possible

summary – economic results• increase in CoE: at 90% capture rate +40%• CO2 abatement cost: 46 - 48 EUR/t CO2

every project is different• comparison to literature (VGB power-tech study*): -13% efficiency loss;

CO2 abatement cost: 47 EUR (at 90% capture rate)• reasons for deviations: freshwater cooling, quality of coal (lower specific

emission)• for serious cost estimations all integration options have to be checked

*CO2-Capture and Storage – VGB Report on the State of the Art, 2004

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Questions ?

E-mail: gerald.kinger@evn.at