advanced coal technology 101 - ncsl

Advanced Coal Technology 101

National Conference of State Legislators ConferenceNovember 1, 2007

Dr. Jeffrey N. PhillipsProgram ManagerAdvanced Coal Generation Options

2© 2007 Electric Power Research Institute, Inc. All rights reserved.

CO2 Capture in Coal Power Systems


CO2 Capture = $, Space, Ultra-Low SO2, and Lots of Energy

Fresh Water

PCBoiler SCR

SteamTurbine

ESP FGDCO2

Removale.g., MEA

CO2 to use or Sequestration

Flue Gasto Stack

Fly Ash Gypsum/Waste

CoalAir

Output Penalty: Up to 30%

• Amine processes commercially available at relatively small scale; considerable re-engineering and scale-up needed (ultra-low inlet SO2 and NO2 also required)

• Steam extraction for solvent regeneration reduces flow to low-pressure turbine; significant operational impact

• Maximizing output and efficiency requires optimal heat integration

• Plot space requirements significant; back-end at existing plants often already crowded by other emission controls

CO2 to Cleanupand Compression

Cleaned Flue Gas to Atmosphere

Absorber Tower

CO2Stripper Reboiler

Flue Gas from Plant

CO2Stripper

Pulverized Coal With CO2 Capture –Integration Issues


PC Operating Units w/ CO2 Capture (Today)

• Three U.S. small plants in operation today– Monoethanolamine (MEA) based

• CO2 sold as a product or used– Freezing chickens– Soda pop, baking soda– ~140 $/ton CO2

• 300 metric tons recovered per day– ~15 MWe power plant equivalent

• Many pilots planned and in development– 5 MW Chilled Ammonia Pilot– Many other processes under development

AES Cumberland ~ 10 MW

Assessment of Post-Combustion Carbon Capture Technology

EPRI

CO2

(Report 1012796)

PC + CO2 Capture: Technology Exists but Larger Scale Demonstrations & Less Expensive Processes Needed


IGCC with CO2 Removal

O2 N2

Air

BFW

BFWSteam

Steam Turbine

HRSG

CoalPrep

Gas CoolingGasificationC + H2O = CO + H2

Sulfur and CO2

Removal

Air Separation

Unit

GasTurbine

Air

Hydrogen

CO2 to use or sequestrationSulfur

ShiftCO+ H2O = CO2 + H2

Steam


Coal Gasification Plants w/CO2 Capture (Today)

• IGCC and CO2 removal offered commercially– Have not operated in an integrated manner

• Three U.S. non-power facilities and many plants in China recover CO2– Coffeyville– Eastman– Great Plains

• Great Plains recovered CO2 used for EOR– 2.7 million tons CO2 per year– ~340 MWe if it were an IGCC

The Great Plains Synfuels Planthttp://www.dakotagas.com/Companyinfo/index.html

Weyburn Pipelinehttp://www.ptrc.ca/access/DesktopDefault.aspx

IGCC + CO2 Capture – Ready for Demonstration but need to decrease costs


Oxy-Combustion Capture Status

Source: Vattenfall

No Commercial Power Plants use Oxy-Combustion today, but:

• Several pilot scale (~1 MW) test units operating

• Vattenfall 30 MWth pilot plant announced

• B&W 30 MWth test facility in Ohio


CO2 Capture Can Be Done Today, But….

• It would increase the cost of electric power from coal significantly• EPRI’s current estimates

– Cost of power from a pulverized coal plant with post-combustion capture would be 60-80% higher

– Cost of power from an IGCC with pre-combustion capture would be 40-50% higher (but IGCCs start out with a higher cost, so won’t necessarily be cheapest option with CCS)

– Cost of oxy-combustion more difficult to estimate with certainty at this stage of development but overall cost of power probably similar to PC + post combustion capture

• Luckily, EPRI also estimates that with a concerted RD&D effort, the cost impact of CCS could decrease dramatically


EPRI PC and IGCC Cost of ElectricityWith and Without CO2 Capture (Illinois #6 Coal)(All IGCC and CCS cases have +10% TPC Contingency for FOAK)

40

50

60

70

80

90

100

110

120

130

SupercriticalPC

GE RadiantQuench

GE TotalQuench

Shell GasQuench

E-Gas FSQ

30-Y

r lev

eliz

ed C

OE,

$/M

Wh

(Con

stan

t 200

6$)

. No Capture

Retrofit CaptureNew Capture

COE Includes $10/tonne for CO2 Transportation and Sequestration


EPRI PC and IGCC Cost of ElectricityWith and Without CO2 Capture (PRB Coal)(All IGCC and CCS cases have +10% Contingency for FOAK)

40

50

60

70

80

90

100

110

120

130

Supercritical PC UltrasupercriticalPC

Shell GasQuench

E-Gas FSQ

30-Y

r lev

eliz

ed C

OE,

$/M

Wh

(Con

stan

t 200

6$)

. No Capture

Retrofit CaptureNew Capture

COE Includes $10/tonne for CO2 Transportation and Sequestration


Relative $/kW Total Plant Cost (2005 = 100%) Plant Net Efficiency (HHV Basis)

USC PC RD&D Augmentation Plan—Expected Benefits Case:Pittsburgh #8 coal, 90% availability, 90% CO2 capture

110

100

90

80

70

602005 2010 2015 2020 2025

40

38

36

34

32

30

Near Mid-Term:• Upgrade steam

conditions to 4200/1110/1150

Mid-Term:• Upgrade steam

conditions to 5000/1300/1300, and then to 5000/1400/1400/1400

Near-Term:• Upgrade solvent from MEA

to MHI KS-1 (or equivalent)• Upgrade steam conditions

from 3500/1050/1050 to 3615/1100/1100

Long-Term:• Upgrade solvent

to ammonium bicarbonate (or equivalent)


IGCC Long-Term RD&D Plan—Expected BenefitsCase: Slurry-fed gasifier, U.S. bituminous coal, 90% availability, 90% CO2 capture

60

70

80

90

100

110

2005 2010 2015 2020 2025 2030

Long-Term• Membrane

separation• Warm gas

cleanup• CO2-coal slurry

Rel

ativ

e Pl

ant C

ost (

$/kW

, 200

5 =

100%

)

30

32

34

36

38

40

Plan

t Net

Effi

cien

cy (H

HV

Bas

is)Mid-Term

• Ion transfer membrane oxygen• G-class to H-class gas turbines• Supercritical HRSG• Dry ultra-low-NOX combustors

Longest-Term• Fuel cell

hybrids

Near-Term • Add SCR• Eliminate spare gasifier • F-class to G-class gas

turbines• Improved Hg detection


What could we do with CO2?

• Put it in the bottom of the ocean– Significant environmental uncertainties

• Make a solid out of it– Large amounts of solids and high energy penalty

• Utilize it – No use for such a large amount

• Geologic Storage– May be best solution but has challenges


CO2 Storage – Main Focus is Injection Into Geological Formations

• Saline reservoirs– 100’s of years capacity– Little experience

• Economical, but lesser capacity options– Depleted oil & gas

reservoirs/enhanced oil recovery

– Unmineable coal beds/enhanced coal-bed methane recovery

• Deep ocean injection not acceptable today

• Mineralization a dreamCourtesy of Peter Cook, CO2CRC


How Does Saline Reservoir Storage Work?

• Inject into deep, high salinity reservoirs

– No impact on drinking water

• Limited data– Few wells penetrate

reservoirs• Large volume potential for storage

– Order of magnitude larger than oil

• Reasonably well distributed across country


CO2 Transportation Issues

• The technology (compressors and pipelines) is relatively straightforward but there are some questions:– What impurities are allowable?– Must it meet current commercial pipeline

specifications?– Liability transfers?


CoalGasification

LeBarge

McElmoDome

St. JohnDome

Sheep Mountain

BravoDome

GasPlants

AmmoniaPlant

JacksonDome

U.S. Has Experience With CO2 Pipelines for EOR.Need to Show It’s Applicable or Can Manage Differences

2,500+ Miles of CO2 Pipe in US Today…350,000 for Natural Gas

CO2 Sources

Natural

Industrial

Pipelines


Socio-political Concerns - Risk & Acceptability

• Leakage risks• Public acceptance• Permitting• Legal/liability Concerns• Environmental impacts

Need everyone, not just engineers, to resolve these issues


Regulatory Risk Uncertainty

• Who has jurisdiction over saline reservoirs?– States or US EPA?

• Who owns saline reservoirs’ CO2 absorptive capability?

• What impurities are permitted and how much?

• Who is responsible if there is a leak of CO2 back into the atmosphere?

Source: USEPA


What’s Next – What’s Needed for Coal?

• Acceleration of the Industry efforts worldwide in addition to governmental efforts

• Cost reductions and efficiency improvements for capture “systems”

• Large scale testing of storage of CO2 in deep saline reservoirs:– >1 million tons of CO2/year at multiple sites– Eliminate permitting uncertainty


Timeline for CO2 Storage & Post-combustion Capture Demos to Meet 2020 Target

Source: DOE Roadmap (modified)

1st demoAEP?

2005 2010 2015 2020

Start 1st 20+MW Injection Demo

Commercial availability of post-combustion CO2capture & storage

Accelerate DOE schedule

Design, permit, build

Inject (4 yr) Monitor

2nd – 5th demos

Background slides


Combustion & Gasification Products


1000ºC


1400ºC


Combustion vs Gasification

• SO2 & SO3 is scrubbed out of stack gas – reacted with lime to form gypsum

• NOx controlled with low NOx burners and catalytic conversion (SCR)

• Flyash removed via ESP or bag filters

• Hg can be removed by contacting flue gas with activated carbon

• H2S & COS are easily removed from syngas and converted to solid sulfur or sulfuric acid

• NH3 washes out of gas with water, thermal NOx controlled by diluent injection in GT, optional SCR for deeper NOx removal

• Ash is converted to glassy slag which is inert and usable

• >90% of Hg removed by passing high pressure syngas thru activated carbon bed

Combustion Gasification


What can you do with coal gasification?

• Produce Electricity– In a Gas Turbine-based Combined Cycle power plant– Emissions approaching that of a natural gas fired power plant

• Make Fuels– Sasol has been making gasoline from coal since the 1950s in

Republic of South Africa – Dakota Gasification has been making “synthetic” natural gas

from lignite since the 1980s• Make Chemicals

– Eastman Chemicals has been doing this since 1980s• Make Fertilizer

– Coffeyville Resources in Kansas makes ammonia-based fertilizer from petroleum coke

• Make Hydrogen– FutureGen project will set the stage for production of H2 from

coal


Steam Cycles vs “Combined” Cycles

• Steam Cycles have – a boiler – a steam turbine

• Referred to as “Rankine” cycle, fossil boiler, “fossil steam” plant, “conventional coal” plant

• Combined Cycles (the “CC” in IGCC) have – a Gas Turbine – a “heat recovery steam generator” (HRSG)– a steam turbine


Conventional Coal Plant

100 MW

12 MW

88 MW

41.5 MW

46.5 MW

39 % Efficiency (HHV basis)

2.5 MW own use

39 MW


Gas Turbine “simple cycle”

100 MW

35 MW

65 MW

35% Efficiency (HHV basis)


Combined Cycle

100 MW

Fuel

35 MW17 MW

65 MW

27 MW

21 MW to condenser

38 MW

17 + 35 = 52 MW 52% Efficiency! (HHV basis)


Combined Cycle

Photo source: Siemens


15MW 79MW

28MW51MW

47MW20MW

9MW

Net Coal to Power: 28 + 20 – 9 = 39% (HHV basis)

19MW

100MW

IGCC schematic from US DOE27 MW


CO2 Capture & Storage (CCS) is Needed to Stabilize CO2 Emissions from US Power Plants


Research Development Demonstration Deployment Mature Technology

Time

Ant

icip

ated

Cos

t of F

ull-S

cale

App

licat

ion

New Technology Deployment Curve for Coal

Not All Technologies at the Same Level of MaturityNot All Technologies at the Same Level of Maturity

Oxyfuel

CO2 Storage

CO2 Capture

IGCC Plants

USCPC Plants

SCPC Plants

1150°F+ 1100°F

<1100°F 1050°F

Advanced USCPC Plants1150°F+1400°F

advanced coal technology 101 - ncsl

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