SynGas Gasifier ALTERNATIVE ENERGY Technology Presentation.
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Transcript of SynGas Gasifier ALTERNATIVE ENERGY Technology Presentation.
SynGas Gasifier
ALTERNATIVE ENERGY
Technology Presentation
COAL GASIFICATION versus COAL COMBUSTION
Basic Gasification Technology
• Dry Feed Entrained Flow Gasifier using: – Pyrolysis – Thermal conversion or destruction of
organics in the absence of oxygen (reducing atmosphere).
– Gasification – Thermal conversion of organic materials at elevated temperatures and reducing conditions to produce syngas (Hydrogen and Carbon Monoxide)
– Steam Reformation – Vaporized water (steam) added to carbon creates syngas (Hydrogen and Carbon Monoxide)
From: NREL:Biomass Gasification Overview, Richard L. Bain, January 28, 2004
ProvisionalPatentEffectiveDate:April 11, 2006
PatentPendingEffectiveDate:
ExclusivePatent RightsAssignedToThermal Conversions, LLC
175 dry ton per day Gasification Plant
www.eastman.com/company/gasification/overview.htm
Coal 12,500 BTU
Syngas
Variable gas compositions available depending upon operation parameters
• Carbon Dioxide • Carbon Monoxide • Hydrogen • Methane • Other
• Ash– Sulfur– Silica– Mercury– Chlorine– Sodium, etc
Removed
Heatup to
1800° F
Pressure80 psi
PlusIonizedWater
Injection
Gasification
Feed for Chemical/ Refinery
Processes and
ElectricalGeneration
Energy Mass Balance(Btu Basis)
0
10
20
30
40
50
60
0 10 20 30 40 50 60
H2 Concentration (mol % dry gas)
Ga
s C
on
cen
tra
tion
(m
ol %
dry
ga
s)
CO
CH4
CO2
H2
Desired operating range for synthesis
H2:CO = 2H2:CO = 1
Syngas composition operating range for pyrolysis/steam reforming system which includes the range of H2:CO most desirable for production of synthesis fuels. Data collected on pilot scale pyrolysis/steam reforming system operated on biomass feedstock. (Schuetzle, et al. 2007)
Gasification Chemistry
• The following chemical equations describe the process that takes place in the conversion of coal or other carbonaceous fuels into synthesis gas.
Process Equations
Combustion with Oxygen: C + O2 ↔ CO2
Gasification with Oxygen: 2C + O2 ↔ 2CO
Gasification with Carbon Dioxide: C + CO2 ↔ 2CO
Gasification with Steam: C + H2O ↔ CO + H2
Gasification with Hydrogen: C + 2H2 ↔ CH4
Water Gas Shift Reaction: CO + H2O ↔ H2 + CO2
Methanation Reaction: CO + 3H2 ↔ CH4 + H2O
SynGas Gasifier Unique Equations
NOx Emission Control:
CO + NOx +H2O ↔ O2CNO + H2O2
Reaction creates Nitroxyl reactive ions and hydrogen peroxide vapor which provides additional quench water purification and final Nitroxyl precipitation into water filters.
SynGas GasifierUnique Equations Continued
Sulfur Emission Control:
CO + SOx +H2O ↔ O2CSO + H2O2
Reaction creates Sulfinoxyl reactive ions and hydrogen peroxide vapor which provides additional quench water purification and final Sulfinoxyl precipitation into water filters.
SynGas GasifierUnique Equations Continued
Metals Emission Control:
O-x + M ↔ MOx
Ionized oxygen reaction creates metal oxides which are coagulated and precipitated into water filters.
Major US Gasification System Vendors and Projects
• E-GAS ConocoPhillips – Upflow, wet fed (slurry)• GE Energy – Downflow, wet fed (slurry)• Shell Gasification – Upflow, dry fed
• All use an entrained flow oxygen-blown system of gasification
• ConocoPhillips (Global Energy/PSI Wabash River) and GE Energy (Tampa Electric Polk Station) have demonstrated and proven technology in commercial scale IGCC plants
Technology Name/
Design Feature
GE Energy
(formerly Texaco)
E-Gas
(ConocoPhillips)
Shell SynGas Gasifier
Feed System Coal in Water Slurry Coal in Water Slurry
Dry coal, Lock Hopper & Pneumatic Conveying
Dry (As Received)
Coal, Air lock Drag Conveyor
Gasifier Configuration
Single Stage Downflow
Two Stage Upflow Single Stage Upflow 4 Stage Horizontal Circular Flow
Gasifier Wall Refractory Refractory Membrane Wall Inconel
Pressure (psig) 500-1000 Up to 600 Up to 600 80
Notes Offered as Quench or with Heat Recovery
Currently only offered with Heat Recovery
Currently only offered with Heat Recovery
Quench Only
Comparison with Major Entrained Flow Gasifiers
Reference: Publication No. LFEE 2005-002 WP MIT Laboratory for Energy and the Environment
Fischer Tropsch Liquid Fuels Process
The Fischer Tropsch Process
Tax Credits
• SynGas gasification projects can qualify for several tax credits:– Investment tax credits– Clean coal technology– Alternative fuels– Bio-mass conversion– Waste conversion– Job creation
PC Emissions Improvements
IGCC Power Plant Mass Flow
Power Plant Efficiency
Efficiency is defined as the amount of electrical energy produced for sale as a fraction of the amount of fuel consumed in the process, expressed as a percentage.
• Conventional – 32 to 37 %• Supercritical – 35 to 43 %• Ultra-supercritical – 45 % potential• Circulating Fluidized Bed – 29 to 34 %• IGCC (Integrated Gasification Combined Cycle)
– 37 to 43 % with potential of 50 %
Electricity Flow, 2005(Quadrillion Btu)
http://www.eia.doe.gov/emeu/aer/contents.html
65.1%
34.9%
31.3%
Efficiency in Electricity Generation by Process
0
10
20
30
40
50
60
70
80
90
100
Eff
icie
nc
y (
%)
www.umweltbundesamt.at/.../site/umweltthemen/industrie/IPPC_Konferenz/donnerstag_kraftwerke/6-_Van_Aart.ppt
Greenhouse Gas Emissions
CO2 Emission Sources
Bio-Mass SynGas Flame