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CLEAN AND GREEN FUELS FOR SUSTAINABLE DEVELOPMENT
Narsimha Reddy KandadiDepartment of Chemical Engineering
Monash University
OUTLINE
• General issues related to sustainable energy• Environmental and pollution problems with current
transportation fuels • Reformulation of transportation fuels • Clean fuel production• GTL Fuels and their advantageous characteristics• Alternative Gaseous and liquid fuels• Synthesis gas/natural gas refinery• Fuel issues for fuel cells• Issues related to Hydrogen Storage • Conclusions
THE DRIVERS TO ENERGY SUSTAINABILITY
Problems/Concerns Drivers Solutions
Exhaustion of fossil fuels
Increasing costs Energy eficiency
Search for alternatives
Removal of subsidies
Inclusion of “externalities”in the cost of energy
Local and regional environmental quality.
Global warming
Desire to improve quality of air and water
Need to avoid climate change
Cleaner fossil fuels, filters, catalizers.
Reduced use of fossil fuels
switch to renewables
CO2 capture.
Security of supply Need to guarantee low prices and abundant supply
Reliance on indigenous energy resources
switch to renewables or nuclear
Safety Avoidance major disasters
Develop intrinsically safe reactors. Storage of spent nuclear fuel
Equity Avoidance of social unrest &humanitarian concerns
Policies that stimulate supplying energy services to the poor
VEHICULAR POLLUTION
Pollution from Automotive Vehicles are responsible for ~One-third of all AIR POLLUTION ~50% of SMOG forming VOCs & NOx
>50% of Hazardous Air Pollutants 90% of CO found in urban air
20 pounds of CO2 emitted every gallon of gasoline burning by the vehicle
Low emissions and good fuel economy are both important for the environment
IMPACT OF AIR POLLUTION ON HEALTH AND ENVIRONMENT
WHO Report(1999) on Health costs due to traffic-related pollution in Europe
Every year air pollution from cars causes 300, 000 extra cases of Bronchitis in Children 15, 000 Hospital Admissions for Heart Disease 395, 000 Asthma attacks in Adults and 162, 000 Asthma attacks in Children in each year
Car pollution kills more people than car accidents
Long-term exposure in adults over 30 years age can cause extra 21,000 premature deaths from Respiratory or Heart diseases
FUELS DECARBONISATION TRENDS
Gasoline Fuel specifications in different countries for 2000 AD
S No
Characteristics California US EU India
1 Lead, g/l 0 0 0 0..5
2 Sulphur, wt ppm 40 185 50-100 200-500
3 Oxygenates All Oxygenates
All Oxygenates
All Oxygenates
Just Ethers
Oxygen, wt%, Max 1.8-2.2 2.1 2.1 2.3
4 Benzene, max vol%
0.8 0.95 1-2 3
5 Olefins, Vol% max 6.0 9.2 5-10 18
6 Aromatics, Vol% Max
25 24 20-30 45
7 Rvp, Kpa max 43.8 60 45-54 70
ADVANTAGEOUS OXYGENATES
The potential benefits of adding oxygenates to gasoline are • Less CO emissions• Reduced unburned hydrocarbon emissions• Decrease in Ozone content in the lower atmospheres of
highly polluted areas• Environment friendly replacement for TEL and aromatics
for Octane requirements for good engine performance• FCC volatile olefins with high photochemical reactivity can
be converted to ethers which decreases volatility and increases octane content with oxygen
FCC GASOLINE ETHERIFICATION WITH ETHANOL WITH NEW BIFUNCTIONAL CATALYST
Etherification Temp,oC
60 65 70 75 80
% Olefins conversion
24 26 41 43 40
% EtOH Conversion
14.1 22.8 26.6 30.3 24.4
Density, g/cc 0.7186 0.7194 0.7208 0.7197 0.7183
Odour Naphtha Pungent Pungent Pungent Pungent
Colour Colorless Colorless Colorless Colorless Pale yellow
VEHICLES WITH NATURAL GAS
• ~ 800,000 - 1.000,000 vehicles in the world running on natural gas
– Russia– Italy– South America– Australia and – North America
• The market position: capable for fuelling vehicles and refuelling stations at an acceptable level of development
• The fuel infrastructure may allow the easy transition to hydrogen supply
SYNTHESIS GAS REFINERYClean and Alternative Molecular Fuels
EMISSIONS PERFORMANCE OF GTL(F-T) DIESEL FUELS
GTL Fuels are far superior to Petroleum derived Diesel
GTL fuel characteristics
• Cetane - 75• Sulphur - ~0• Aromatics - ~0
Emissions reduction compared to current Diesel
0
20
40
60
80
100
HC CO NOx PM
PollutantsP
oll
uta
nts
red
uct
ion
,%
HYDROGEN – IDEAL
ENVIRONMENT FRIENDLY FUEL • Decarbonise the fuel sphere• Can be realized the zero emission transportation• Can be used in both conventional ICE and Fuel
Cells with water as effluent• Unique combustion characteristics lean burning
with air without NOx –SMOG precursor• Avoids the global climate changes as it can’t
produce CO2• No particulates and unburnt Hydrocarbons
DME AS AN ALTERNATIVE FUEL
• Stationary Applications – Power Plants– Diesel Gensets– Ceramic and Glass Industry
• Transportation– Diesel Engines– CNG
• Fuel for Fuel Cells
DME ENVIRONMENTAL ISSUESPURE DME DOES NOT POSE ANY ENVIORNMENTAL ISSUE DUE TO PHYSICALLY LIKE LPG. LPG INDUSTRY HAS AN OUTSTANDING SAFETY
RECORD 150 000 T/A OF DME USE AS AN AEROSOL PROPELLANT IS BECAUSE OF
ITS ENVIORNMENTALLY BEGING CHARACTERSTICS I.e.o NOT HARMFUL TO OZONE LAYERo READILY DEGRADES IN THE TROPOSPHERE TO CO2 AND H2O o NON TOXICo NON CARCINOGENICo NON TETRAGENo NON TERATOGENo NON MUTAGENo NON CORROSIVE
DISPLAYS A VISIBLE FLAME OVERWIDE RANGE OF AIR FUEL RATIO HEAVIER THAN AIR HENCE NEEDS SAME HANDLING AND SAFETY CARE
AS PROPANE AND LPG
HOW EFFICIENT IS OUR CURRENT VEHICLE ?
ADVANTAGES OF FUEL CELLS OVER OTHER POWER SOURCES
Environmentally friendly High power density High energy conversion efficiency Operation at low temperatures and pressures Zero to very low emissions dependent on fuel Site flexibility Fuel flexibility Quiet operation Cogeneration capability Responsiveness to load variations
SUITABLE FOR MULTIPLE APPLICATIONS, INCLUDING AUTOMOTIVE
AUTOMOTIVE FUEL CELL DRIVERS
• Kyoto agreement requires CO2 reduction• Europe will reduce car CO2 emissions• Aggressive fuel/CO2 taxes• California Zero Emission Vehicle by 2003
Public policy will help build a market for Fuel Cell Vehicles
COMPARISON OF EFFICIENCY
AUTOMOBILE POWER SYSTEMS
HYDROGEN ECONOMY CONCEPTUAL APPROACH
FUELS ISSUES FOR FUEL CELLS IN TRANSPORTATION SECTOR
PROJECTED FC VEHICLE PERFORMANCE: LIGHT WEIGHT HYBRID VEHICLE
FUELS AND PROCESSING STEPS IN FUEL PROCESSOR FOR FUEL CELLS
Fuel cellFUEL PROCESSOR
Fuel evaporation Syngas generation Water-gas shift CO clean-up
Natural GasGasolineAlcohol + O2 + H2O
PowerH2
60 - 200°C R-OH (l) R-OH (g)HC (l) HC (g)
Partial OxidationSteam ReformingAutothermal Reforming 750 - 1000°C HC + H2O + O2 CO, H2, CO2, H2O
High TemperatureMedium TemperatureLow Temperature 200 - 550°C CO + H2O CO2 + H2
Preferential OxidationMembranes ambient - 70°C CO + O2 CO2
FUELS FOR FUEL CELL POWERED VEHICLES
[Fuel Report by California Energy commission, July’99]
PROMISING FUEL PROPERTIES OF METHANOL FOR PEM FUEL CELLS
• Liquid having high energy density at ambient temperature and pressure,
• High energy storage capacity• Simple molecule• Sulfur free • Fairly easy to reform into hydrogen rich gas –
lower reforming temperature • High hydrogen to CO2 ratio in comparison with
other processing options• Low carbon monoxide yield(CO)
MONASH’S FUEL PROCESSOR AND FUEL CELL SYSTEMS
The fuel processor with C1 Fuels and H2 storage for both PEMFC & AFC with major Australian Fuels-syngas, NG. LPG etc.
I. COMPACT FUEL REFORMER WITHOUT THE CO CLEANUP STEP • MeOH/DME/Methyl formate reforming
II. CARBON DIOXIDE FREE HYDROGEN PRODUCTION
• Catalytic Decomposition of NG & LPG CH4 = C + 2H2 H = + 75.6Kj/mol
C2H6 = 2C+ 3 H2 H = + 83.7Kj/mol
C3H8 = 3C + 4 H2+ H = + 103.8Kj/mol
nC4H10 = 4C + 5 H2+ H = + 125.5Kj/mol
• Catalytic Reforming of NG & LPG to Aromatics and H26CH4 = C6H6 + 9H2
3C2H6 = C6H6+ 6 H2
C3H8 = C6H6 + 5 H2
III. NOVEL MATERIALS FOR HYDROGEN STORAGE• Hybrid Novel Carbon Materials with Metal Hydrides
ON-BOARD HYDROGEN STORAGE
The challenges of fuelling for fuel cell vehicles
• The biggest issue is how to provide fuel
• The space needed to store the fuel on board the vehicle
• Efficient ways for processing fossil fuels on board must be developed
• Even though reforming is a gentler process than combustion, it still introduces trace emissions, which will dragged down overall efficiency
Efficiency and Technical difficulty – Direct hydrogen vehicles are the most efficient, followed by on-board processor of methanol and then gasoline
HYDROGEN INFRASTRUCTURE AND STORAGE
HYDROGEN PRODUCTION AND DISPENSING
TARGETS AND STATUS
ON – BOARD OFF-BOARD
CONCLUSIONS• Utility Sustainable energy concepts are critical for global
climate change and resource diversification
• Clean as well as molecular fuels are going to play prominent role to transition to decarbonisation of fuels
• Synthesis gas will be the feedstock for both clean as well as molecular fuels for both Combustion engines and Fuel Cells
• C1 oxygenates such as MeOH, DME, Methyl formate can be efficient conventional fuels and source for low temperature hydrogen production by steam reforming
• CO2 free H2 production fro low temperature fuel cells from NG and lower hydrocarbons have both economic and technical advantages
• New adsorbents for H2 storage can realize the zero emission concepts