“Gasification 101”

Steve Jenkins

CH2M HILL

Gasification Technologies Council Workshop

March 13, 2008

2

Topics

• Gasification and IGCC “101”

• History of modern coal gasification and IGCC

• Technologies

• Environmental issues

3

What is Gasification?

Fuels

Chemicals

Power

Syngas

4

What is Gasification?

•Thermal conversion of coal at 1,400-2,800°F,

with a limited supply of air or oxygen, into a

synthetic gas, or syngas

• It’s not combustion!

• Gasification uses only a fraction of the oxygen that would be needed to burn the coal

– Combustion: excess air

– Gasification: air starved

5

Combustion

C + O2 → CO2

Combustion of coal produces CO2 and

heat, which is used to produce steam for power generation

in a steam turbine generator

6

Gasification

7

Main Gasification Reactions

8

What’s in the Syngas?

• Syngas contains mostly hydrogen, carbon

monoxide, water vapor, carbon dioxide, and

methane

• Syngas can be used as a fuel to generate power,

or to make chemicals & fuels

• Heating value is 250 Btu/scf (1/4 of natural gas)

– Air-blown gasifier syngas includes a large amount of

nitrogen, and has a heating value of about 125 Btu/scf

9

How has Gasification been Used?

• Making “town gas” from coal (1792)

• Manufactured gas plants – prior to discovery and use of natural gas

10

How has Gasification been Used?

• Fuels

– WWII: Germany – no access to oil, but lots of coal

– “Fischer-Tropsch” process produced diesel and gasoline from syngas

– Cars and trucks used small wood gasifiers for fuel

wood gasifier

11

Modern Coal Gasification

12

Modern Coal Gasification

95% pure

oxygen

Source: Eastman Chemical

13

SASOL

• Located in South Africa

• Started up in 1955

• Lurgi gasifiers (97)

• Fischer-Tropsch process converts syngas to liquid fuels

• Now gasifies 90,000 tons coal/day into 150,000 barrels/day of liquid fuels

Source: SASOL

14

Eastman Chemical - Kingsport, Tennessee

• “Coal-to-Chemicals” Facility

• Started up in 1983

• Originally part of Eastman Kodak

• Texaco (GE) gasifiers

• Gasifies 1,300 TPD Central Appalachian medium sulfur coal

• Sulfur compounds and ash are removed from the syngas

• Syngas is used to make methanol, acetic acid, acetic anhydride, methyl acetate… and

Source: Eastman Chemical

15

Consumer Products

16

Dakota Gasification CompanyGreat Plains Synfuels Plant

• Beulah, North Dakota

• Part of Basin Electric Power Cooperative

• Started up in 1984

• Converts 16,000 tons/day

of North Dakota lignite to:

– Synthetic natural gas

– Fertilizers

– Chemicals

Source: Dakota Gasification

Source: Dakota Gasification

Source: Dakota Gasification

17

Coffeyville ResourcesCoal to Fertilizer

• Ammonia/fertilizer plant in Kansas

• Used high-cost natural gas to make hydrogen for ammonia

• Added pet coke gasification system

– GE Energy (Texaco) gasifier

– Produces syngas with high H2 content

– H2 is used to make ammonia

– Significant production cost savings and increased profitability

Source: Coffeyville Resources

18

Gasification Plants

• There are 142 operating gasification plants (not IGCC plants) with a total of 420 gasifiers in operation worldwide

• They are used primarily for gasifying coal, pet coke, natural gas, and refinery wastes

• They produce syngas for use in making chemicals, synthetic natural gas, hydrogen for ammonia, Fischer-Tropsch transportation fuels, and some power

19

Proposed Gasification Plants

• 25-35 projects across North America

• Drivers

– High cost of natural gas where it is the feedstock for downstream products

– Production of lower cost transportation fuels

– Syngas or SNG to replace high-cost natural gas

– High cost of power: self-generation

– Low-cost, available feedstocks

– Federal and state incentives

• Energy Policy Act of 2005

20

Proposed Gasification Plants

• Feedstocks include

– Coal

– Pet coke

– Refinery waste streams

– Biomass

– Blends

21

Proposed Gasification Plants

• Products include:

– Ammonia

– Fischer-Tropsch fuels (diesel, naphtha)

– Hydrogen

– Methanol

– Methyl acetate

– SNG

– Urea

– Urea Ammonium NitrateSources: Rentech, Coffeyville Resources

22

Combined Cycle Power Generation

23

What is Simple Cycle Power Generation?

• Simple cycle combustion turbine burns a fuel

– Fuel oil

– Natural gas

– Biogas

– Jet fuel

• Combustion turbine turns a generator, producing electricity

• Hot exhaust gas (>1,000 °F) exits though a stack

• Efficiency = ~35%

Source: Siemens

24

What is Combined Cycle Power Generation?

• Hot exhaust gas from gas turbine is ducted through a boiler, where steam is produced

• Steam is piped to a conventional steam turbine-generator, producing more electricity

• Combined cycle plant efficiency = 55+%

• Commercially proven at hundreds of installations

25

Combined Cycle – 2 Gas Turbines and 1 Steam Turbine

Source: Calpine

26

How Does IGCC Work?

• Integrate the coal gasification process with a combined

cycle power plant

• Instead of using natural gas or fuel oil in the combined

cycle power plant, convert low-cost coal to a clean-

burning syngas and use it as a fuel

• Advantages of IGCC

– Can be designed to use a wide range of feedstocks

– Takes advantage of high efficiency combined cycle power generation technology

– Has low emissions and saleable byproducts

27

IGCC

Combined Cycle

Power Plant

Gasification Plant

Source: DOE

28

Where has IGCC Been Demonstrated?

MHIcoalNakoso, JapanClean Coal Power R&D

Co.

Multiple Japanese

Utilities; MITI; CRIEPI

Prenflocoal/cokePuertollano,

SpainPuertollanoELCOGAS

GE Energycoal/cokeMulberry, FLPolk Power

StationTampa Electric

ConocoPhillipscoal/cokeW. Terre Haute, IN

Wabash RiverSG Solutions

Shellcoal/biomassBuggenum, Netherlands

Willem Alexander Centrale

Nuon

Gasifier Technology

FeedstockLocationFacilityCompany

29

Nuon Willem-Alexander CentraleBuggenum, The Netherlands

• Started up in 1993

• Shell technology

• 2,000 tons/day coal

• 253 MW net

Source: Nuon

30

SG SolutionsWabash River Generating StationW. Terre Haute, IN

• Started up in July 1995

• ConocoPhillips E-Gas™technology

• 2,000 tons/day coal, pet coke, blends

• Repowered existing unit

• DOE Clean Coal Technology Program

• 262 MW net output

Source: ConocoPhillips

31

32

Tampa Electric CompanyPolk Power StationMulberry, FL

• Started up in July 1996

• GE Energy gasifier

• 2,000 tons/day coal and blend with pet coke

• DOE Clean Coal Technology Program

• 252 MW net outputSource: TECO

33

C o a l

250 0 T P D

R o d M i ll

W a te r

S lu rr y

T a n k

S lu rr y

Pu m p

M ain A ir

C om p ress or

32 M W

P ro d u c t

C o m p re ss o r s

1 8 M W

O x yg e n

210 0 T P D

C o a l/W a te r

S lu r ry

C o ld

B o x

D ry e r s

L o ck h o p p e r

S la g &

W a te r

F lya sh

& W a te r

Co m p resso r T ur b in e

C o m b u s to r

G e n e ra to r

1 9 2 M W

C le a n

S ta ck

G a sA ir

C o n d e n se r

C o n d e n sa te

P u mp

1 6 0 0 p s ig

S a tu r a te d

S te a m

C le a n S yn ga s

W a te r Sc r u b b e r

D i lu e n t N it ro g e n

5 8 0 0 T P D

R a d ia nt

Sy n ga s

C o o le r

G a s if ie r

C o n v e c t ive

Syn g a s

C o o le r

F ina l F ilte r

C o o l in g

W a te r

M D E A Ac id G a s R e m o va l

Ac id G a s

H 2S + C O 2

T o S u lfu ric

A c id P la n t

C o o l in g

W a te r

55 ps ig

S team

E c o n o m iz e d

B o i le r

F e e d w a te r

B F W Pu m p

H e a t R e c o ve ry

St e a m G e n e ra to r

(H R S G )

G e n e ra to r

1 2 5 M W

Ste a m T u r b in e

R a w

Syn g a s

C O S

H yd ro ly s is(C O S H 2S )

F ly as h &

C h lo r id e

R e m o v a l

Source: TECO

34

ELCOGASPuertollano, Spain

• Started up in 1998

• Prenflo technology (modified Shell)

• ~2,000 tons/day of 50/50 blend of local subbituminous coal and pet coke

• 260-280 MW net

Source: Elcogas

35

Clean Coal Power R&D Co.Nakoso, Japan

• Started up in late 2007

• MHI technology

• ~1,700 tons/day of subbituminous coal

• 250 MW net

Source: MHI

36

Gasification Technologies for IGCC

GE

ConocoPhillips

E-Gas

ShellSiemens

MHI

KBR

37

ConocoPhillips (E-Gas™ process)

• Coal-water slurry feed

• Oxygen-blown

• Refractory-lined gasifier

• Good for a wide range of coals, from pet coke to PRB, and blends

Source: ConocoPhillips

38

GE Energy

• Coal-water slurry feed

• Oxygen-blown

• Refractory-lined gasifier

• Good for bituminous coal, pet coke, or blends of pet coke with low-rank coals

• Developing dry-feed gasifier for use with low-rank coals

Sources: GE, DOE

39

Kellogg Brown & Root (KBR)

• Dry feed

• Air-blown transport reactor

• Pilot tested on wide range of coals at Power Systems Development Facility in Alabama

• Targets low-rank coals

• Mississippi Power Co. to develop full-scale 560 MW plant

– LigniteSource: Southern Company

40

Mitsubishi Heavy Industries (MHI)

• Dry feed

• Air-blown

• Good for low rank coals

• 250 MW demonstration plant started up in Japan in November 2007

• Reached full load on syngas last week

Source: MHIl

41

Shell

• Dry feed (coal is crushed and dried and then fed into gasifier)

• Oxygen-blown

• Waterwall in gasifier

• Good for wide variety of feedstocks, from pet coke to PRB

Source: Shell

42

Siemens Fuel Gas

• Dry feed

• Oxygen-blown

• Waterwall screen in gasifier

• Good for a wide variety of feedstocks, from bituminous to low-rank coals

Source: Siemens

43

Proposed IGCC Projects (air permits final or in review)

In ReviewKBRLigniteLiberty, MSKemper CountyMississippi Power

In ReviewConocoPhillipsPRB/Illinois #6/pet coke

Taconite, MNMesabaExcelsior Energy

FinalGECoalTaylorville, ILTaylorville Energy Center

Tenaska/MDL Holdings

FinalGECoalOwensboro, KYCash Creek Generation

MDL Holdings/GE

In ReviewConocoPhillipsPRB/pet cokePort of Kalama, WA

Pacific Mountain Energy Center

EnergyNorthwest

FinalGECoalEdwardsport, INEdwardsportDuke Energy Indiana

In ReviewGECoalOH; WV Great Bend/Mountaineer

AEP

Permit StatusGasification Technology

FeedstockLocationFacilityCompany

44

Capacity of Proposed IGCC Facilities

• New IGCC plants based on sufficient syngas to

fully load two “F class” gas turbines

• Gross output: 780 MW

• Internal load: 150 MW (19% of gross output)

• Net output: 630 MW

• Feedstock requirements

– Pet coke: 4,000 tons/day

– Bituminous coal: 6,000 tons/day

– PRB:7,800+ tons/day

45

IGCC Availability Improvements

• Lessons learned from 10+ years of experience n

– Materials of construction

– Spare equipment

– Gasifier refractory

– Burner design

• Next generation of IGCC should achieve 85+% availability

– Spare gasifier train may achieve 90% availability

– Back-up fuel can also improve unit’s availability

– Options must be balanced against cost of capital vs. fuel

46

Environmental Issues

47

Air Emissions

48

Technology Comparison

Pre-combustion clean-up of

small volume of syngas

Clean fuel and SCR

Post-combustion clean-up of

large volume of exhaust gas

Emission Emission ControlControl

Syngas in gas turbine

Natural gas in gas turbine

Coal in boilerCombustion Combustion

SyngasNatural gasCoalFuelFuel

Coal--FeedstockFeedstock

IGCCIGCCNGCCNGCCPCPC

49

IGCC - a Different Environment Than PC and NGCC

• Gasification occurs in a reducing atmosphere

– sulfur compounds are liberated as H2S

– removed by refinery industry technologies to levels ≥98%

• NOx is controlled by saturating the syngas stream with water or steam (cools the flame) and injecting N2 with syngas (as diluent)

50

Comparison of Air Emission Controls: PC vs. IGCC

Pre-sulfided activated

carbon bed

Wet scrubber, high

temperature cyclone,

candle filter

Syngas saturation and

N2 diluent

Acid gas removal absorbs H2S and

COS

IGCCIGCC

Inject activated carbon

ESP or baghouse

Low-NOx burners and SCR

FGD system absorbs

SO2

PCPC

MercuryMercuryPMPMNOxNOxSOSO22

51

Air Permitting

• Same coal delivery and handling emission points as PC units

• Same HRSG stack emission points as NGCC

• Air permitting requirements

– Air dispersion modeling

– BACT analysis

– Emission controls

– Fugitive dust controls

• Coal delivery, unloading and handling

– Cooling towers

52

New Source Performance Standards

• Final EPA regulations, June 2007

• IGCC is covered as an Electric Utility Steam

Generating Unit, just like PC boilers, if:

“The combined cycle gas turbine is designed

and intended to burn fuels containing 50 percent

(by heat input) or more solid-derived fuel not

meeting the definition of natural gas on a 12-

month rolling average basis”

53

Water Issues

54

Water Consumption and Liquid Discharge Permits

• Water permits

– Consumptive use permits

• raw water treatment

• reverse osmosis and demineralizer

– State and local permits for potable water treatment and supply systems

– CWA Section 316(b) cooling water intakes

– NPDES permit for stormwater and wastewater discharges

• Zero liquid discharge system can eliminate need for discharge

– Local permits for sanitary sewer discharges or package treatment plants

55

• For IGCC reference plant:

– 780 MW (gross) unit, 464 MW is from gas turbines and 316 MW is from the steam turbine

– Only 40% of total output is from steam turbine, so cooling water make-up needs are decreased by ~60%

• No FGD system needed for IGCC, so no need for water to produce limestone slurry

• IGCC can require water for preparing coal slurry and for syngas washing and cooling

Water ConsumptionIGCC vs PC

56

Comparison of Water Use

0

10

20

30

40

50

60

70

80

90

100

SCPC

IGCC

% C

om

pa

red

to

S

CP

C

Source: DOE

30% less

57

Solid Byproducts

58

• Ash is removed in molten form, then quench-cooled to form glassy, inert, saleable slag

Solid Byproducts

Molten slag

59

Slag

• Very similar to slag from coal-fired boilers, but….

• It is not regulated as a coal combustion byproduct under RCRA, and does not have the same Bevill exclusion from Subtitle C (hazardous wastes)

• However, gasification slag does have a Bevill exclusion as a mineral processing waste

• Mineral processing wastes, as listed in 40 CFR 261.4(b)(7) include:

– “Gasifier ash from coal gasification”

60

Slag Use

• Used for making

– Cement

– Asphalt filler

– Roofing shingles

– Sand-blasting grit

61

Other Byproducts

• Sulfur

– Recovered in molten form

– Commercially proven processes from refinery industry

– Transported by rail or truck

• Sulfuric acid

– Commercially proven in many industrial processes

– Transported by rail or truck

62

Questions?

63

Contact Info

Steve Jenkins

CH2M HILL

Tampa, FL

813-874-6522, ext. 4141

steve.jenkins@ch2m.com