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Nature Of Hydrogen Demand for Fuel Cells
And NMRL’s Experience on Onsite Hydrogen Generation
S Roy Choudhury, J. RangarajanNaval Materials Research Laboratory, Ambernath-421506
Hydrogen Provision
• Distributed hydrogen retail outlets for mobile / stationary applications– Compressed H2 transport by pipelines like
CNG network– Onsite H2 generation from other feed stocks
• Coal• Hydrocarbons• Alcohols• Ammonia
Hydrogen Provision
• Online/onboard hydrogen generation for mobile systems – Reforming /cracking of hydrocarbon feed
stocks– Reforming/cracking of alcohols– Other inorganic/organic feed stocks
Ammonia cracking
Hydride hydrolysis/cracking
H2 quality
Impurity tolerance increases with increase in operating temperature of fuel cells
Low temperature acid FCs
Phosphoric acid fuel cell• Operates at 130-
2000C• CO tolerance < 2%• S and Cl in ppm level
Polymer electrolyte fuel cells
• Operates at 60-800C• CO tolerance in ppm
level• S & Cl in ppm level
Limits the primary source of fuel
Low temperature alkaline FCs
• Operates around 120-1700C• High CO tolerance
• CO2 tolerance in ppm level
• Cl and S in ppm level
Difficult for terrestrial application
High temperature FCs
Solid Oxide FCs
• Can take CO as fuel
• S & Cl in ppm level
Molten Carbonate FCs
• Can take high CO
• S & Cl in ppm level
The Key issuesThe Fuel Quality
Fuel cells are advanced power generation devices
requires quality feedstock, free from sulfur
The oil refineries have to provide uniform low sulfur fuels.
The Fuel Quality
Fuel cells are advanced power generation devices
requires quality feedstock, free from sulfur
The oil refineries have to provide uniform low sulfur fuels.
The Key issues
The conversion Devices
High cost for CO removal – PEMFC
Low reformer cost – PAFC, SOFC, MCFC
Compact thermal systems to realize mini converters
The conversion Devices
High cost for CO removal – PEMFC
Low reformer cost – PAFC, SOFC, MCFC
Compact thermal systems to realize mini converters
Fuel cell program in NMRL
Fuel cellOur mission
To develop totally indigenous fuel cell for Indian armed forces & commercial use
All necessary subsystems like fuel processor, startup systems etc.
Spin off benefits
Achievements so far …
Catalyst Electrode Acid holder
matrix Graphite gas
distributor plate
Acid management systems
Humidifiers Thermal systems Power conditioners
Online hydrogen generation devicesHydrogen filter systems
Prototypes :- Fuel cell based power packs with all accessories
NMRL’s View
Onsite hydrogen generation is the way to introduce Fuel Cells successfully
• For mobile application – supply purified H2 from onsite local generation center – PEMFCs, PAFCs
• For stationary application – build onsite H2 generation plant – PAFCs, SOFC
NMRL’s experience in onsite hydrogen generation for fuel
cells
Generation of H2 for possible fuel cell applications
From organic feed stocks
From inorganic feed stocks
Alcohols Hydrocarbons
methanol
ethanol
CNG LPG Naptha, diesel etc.
NH3
Hydrazine
NMRL’s interest
Bio H2 using algae
storage of H2 for possible fuel cell applications
Compressed gas Metal hydrideNaAlH4 etc.
Occluded H2C SWNT, Organo-metallic
framework etc.
Chemical hydrides
Low temperature
storage
High pressure light weight
storage
NaBH4 , CaH2
NMRL’s interest
H2 Content & requirement
Material H2 wt % H2 lit/lit @NTP
CH3OH 18.75 5250
CNG 50.00 8
CaH2 9.52 2133**
NaBH4 21.05 4715**
Comp H2
@200atm
100.00 200
** considering powder density=1
1 kWatt power H2 consumption
(lpm @ NTP)
At 100 % efficiency
5.88
At ~65% efficiency (~0.6V cell pot)
9.04
At ~65% efficiency (~0.6V cell pot)
With 70% utilization
13
Hydrogen generation devices
Reformers Online generation of
hydrogen by methanol reforming
Various configurations, for 2lpm (100W), 80 lpm (5kW),900 lpm (60kW) power packs
Output CO level <0.5%
Hydrogen crackers One shot use Suitable for subwatt to 100
watt systems Different options:-
super-corroding alloy /Calcium hydride hydrolysis
NaBH4 in caustic base solution – catalyst induced hydrolysis
Pilot methanol reformer – 8-10 lpm hydrogen output for process design and scale up studies (1997)
Compact reformer 1999 (80 lpm hydrogen)
Bukhari reformer 2003
2-5 lpm of hydrogen
Instrument free, very compact, zero powered / rotating device
Evolution of methanol
reformer at NMRL
Evolution of methanol
reformer at NMRL
High capacity methanol reformer , 50nM3/hr –2003 hydrogen, suitable to ~60kW PAFC power pack
Process design of reformer – NMRL
Detail engineering, control systems and installation – Xytel India
Commissioning - NMRL
Evolution of methanol
reformer at NMRL
Evolution of methanol
reformer at NMRL
Hydrogen generator for small fuel cells
Liquid phase refillable cracker-NaBH4 in caustic •Catalytic (Pt on IRA-100 resin) hydrolysis•Capacity 0-2watt•Protable, orientation free usage,•Floating type
Super corroding alloy, one shot cartridge• Capacity 5-25 watt•Controlled water hydrolysis
CaH2 based, one shot cartridge• Capacity 50-150 watt• Controlled water hydrolysis
Thermal systems• Snadwich type steam heater/cooler for
quick pre-heating and heat removing of PAFC stacks
Bayonet type forced methanol based catalytic heater for compact reformer
Capillary action based natural methanol catlytic burner
Bayonet type natural & fan based hydrogen heater Cartridge type humidifier with hydrogen heater
NMRL’s Fuel Cells – Products available for commercial usage
700-1000 watt PAFC based UPS / generator with built in compact methanol reformer
Delivers 220V AC, 700-1000VA PAFC battery (35 Kg) Nova-1 / 2
Nominal power of 1000 watt
100 watt self contained power pack
•Output :- 12+0.05 V DC upto 100 watt (max)•Size 52x27x25 cm (12Kg)•Hydrogen source by hydride cracking•Hydrogen source by compact catalytic burner based reformer
Conclusion
• Hydrogen source, generation methodology & fuel cell type – critical for successful application
• Available supply infrastructure can be catered for hydrogen application
– This is possible through onsite hydrogen generation
Generally Hydrogen is produced in industry at the expense of utility
For fuel cell application utility is generated at the expense of
hydrogen
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