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Integrated Hydrogen Production, Purification & Compression
Demonstration Project
Tony Boyd , A. Gulamhusein, A. Li ( Membrane Reactor Tech. Ltd. )Satish Tamhankar ( Linde North America Inc. )David DaCosta ( Ergenics Corp. ), Mark Golben ( ERRA)
AIChE Spring National Meeting 2010
March 2010 AIChE Spring Meeting2
DOE Project Objectives
Develop an integrated system that directly produces high pressure, high-purity hydrogen from a single unit.
Phase 1:• Task 1: Verify feasibility of the concept, perform a detailed techno-economic
analysis, and develop a test plan (Complete)
• Task 2: Build and experimentally test a Proof of Concept (POC) integrated membrane reformer / metal hydride compressor system (Ongoing)
• POC Performance Targets and Design Basis– Production capacity of 15 Nm3/hr H2
– Hydrogen output pressure of 100 bar
– Hydrogen purity of 99.99%
– Production unit efficiency of >70% and compression efficiency of > 70%
– Unattended operation
March 2010 AIChE Spring Meeting3
Design Basis
Our SystemConventional
Natural GasMethanolGasoline/Diesel
PSA
WaterFuel
Processor Water CompressorPurificationShift
Converter
SyngasH2, CO, CO2, N2
CO2, N2
H2, CO2, N2 H2 (99.99%)
CO + H2O
CO2 + H2
SMR
ATR
POX
Natural GasMethanolGasoline/Diesel
PSA
WaterFuel
Processor Water CompressorPurificationShift
Converter
SyngasH2, CO, CO2, N2
CO2, N2
H2, CO2, N2 H2 (99.99%)
CO + H2O
CO2 + H2
SMR
ATR
POX
Natural GasMethanolGasoline/Diesel
PSA
WaterFuel
Processor Water CompressorPurificationShift
Converter
SyngasH2, CO, CO2, N2
CO2, N2
H2, CO2, N2 H2 (99.99%)
CO + H2O
CO2 + H2
SMR
ATR
POX
Integrate membrane reformer (MRT) & metal hydride c ompressor (MHC, Ergenics)
• Lower capital cost compared to conventional fuel processors by reducing component count and sub-system complexity.
• Increase system efficiency by:– Directly producing high-purity H2 using high temperature, selective membranes;
increased flux due to suction provided by the hydride compressor
– Improved heat and mass transfer due to inherent advantages of fluid bed design
– Equilibrium shift to enhance hydrogen production in the reformer by lowering the partial pressure of hydrogen in the reaction zone
– Using waste heat from reformer to provide over 20% of H2 compression energy
Natural GasAlternative
Fuels
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural GasAlternative
Fuels
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
March 2010 AIChE Spring Meeting4
Flow Schematic
NaturalGas
Water
ROG
Hydrogen
Vent
Air
Vent
Air
AirComp.
GasComp.
Vapor-izer Fluid Bed
MembraneReactor
Metal HydrideCompressor (MHC) Skid
Fluidized Bed Membrane Reformer (FBMR) Skid
March 2010 AIChE Spring Meeting5
Autothermal Membrane Reformer
Autothermal Fluidized Bed Membrane Reformer (FBMR)
• Autothermal heating (air addition) eliminates need for heat transfer surfaces
• Reformer vessel design uses lower cost metals (carbon steel)
• Novel membrane assemblies ease installation and maintenance
• Fluidized bed greatly enhances mass and heat transfer
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
NG/Steam
Off-gas
H2
Air
March 2010 AIChE Spring Meeting6
Membranes
New Membrane Design• Membranes operate at 550ºC, 25 barg • Large area, planar membrane modules installed
and tested in multiple runs (6” x 11” x ¼”) with double-sided 25µm palladium alloy foils
• Thinner, higher-flux membranes (15 µm foil) for reduced cost successfully tested in lab
y = 27.076x25um foil
y = 45.97x15um foil
0
10
20
30
40
50
60
0.0 0.5 1.0 1.5∆P0.5 (bar0.5)
H2 pe
rmea
nce
(m3 /m
2 .h)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
March 2010 AIChE Spring Meeting7
Burner / Vaporizer / Air Preheater
• Single unit preheats, vaporizes & superheats natural gas – water mixture
• Combustion air pre-heater incorporated around unit reduces overall foot print
• Detailed design effort conducted, including CFD modeling
CFD model shows hot air velocity gradients over exchanger tubes
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
March 2010 AIChE Spring Meeting8
Reformer Skid
Prototype Design Advantages• Can operate independently from MHC• Greater accessibility• Ideal for component testing and
optimization
Future Generation Optimization• Compartmentalize to reduce classification
zones• Fully integrate with MHC to eliminate
redundant systems & improve efficiency
Installed outdoors at NRC’s Institute for Fuel Cell Innovation (Vancouver BC)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
9’ x 6’ footprint12’ high with reactor
March 2010 AIChE Spring Meeting9
Metal Hydride Compressor • Multi-stage metal hydride hydrogen compressor
creates work (pressurized gas) from heat
• Ergenics engineers the composition of hydride alloys to operate at different pressures
• Staging progressively higher pressure alloys lets the compressor achieve very high pressures, using only the energy in hot water
0.0 0.2 0.4 0.6 0.8 1.0 1.20.1
1
10
100
50
5
0.5
25oC
175oC
100oC
40oC
70oC
Pre
ssur
e, A
tm H
2
Hydrogen:Metal Atomic Ratio
Step 1: Low pressure hydrogen is absorbed by an alloy at ambient temperature.
Step 2: Hot fluid heats the alloy causing the hydrogen to be released with an exponential increase in pressure.
27 psi 210 psi
H2 inlet7 psia
H2 output1515 psia
HydrideAlloy
1
HydrideAlloy
2
HydrideAlloy
3
Cold Water
Hot Water
27 psi 210 psi
H2 inlet7 psia
H2 output1515 psia
HydrideAlloy
1
HydrideAlloy
1
HydrideAlloy
2
HydrideAlloy
2
HydrideAlloy
3
HydrideAlloy
3
Cold WaterCold Water
Hot WaterHot Water
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
March 2010 AIChE Spring Meeting10
Metal Hydride Compressor
Less than 0.5 bara (7 psia) suction
pressure
>105 bara (1,515 psia) discharge
pressure
The next generation system will have a higher level of integration, eliminating the MHC balance-of-plant water heater, fan cooler and c ontrol panel.
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
MHC skid
FBMR
2 MHC beds
Single MHC stage
March 2010 AIChE Spring Meeting11
System Results (FBMR)
• First round of tests completed– 11 reformer skid runs of varying
membrane loads completed
– System was continuously operated for >425 hours, including one week of unattended operation
• Smooth operation & isothermal membrane zone (~10°C variation)
• FBMR results agreed with model predictions– > 7 Nm3/hr production (without boost from MHC operation)
– Methane conversions of > 60%
• Performance decreased in last run due to partial catalyst deactivation– Found to be trace slip of sulphur through natural gas guard bed
• FBMR conditions stable during integrated system operation– MHC cyclic operation has minimal impact on FBMR temperature and pressure
• Product Purity– Product impurity levels consistent during run (99.9 to >99.99%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
Natural Gas
Hydride Thermal
Compressor
Water FuelProcessor
Compression
CO2, N2
MembraneReactor
Air H2 (99.9999%)
March 2010 AIChE Spring Meeting12
System Results (MHC)
On regulated cylinder H2, suction pressure (2Y axis) varies from 6 psia to 9 psia with each half-cycle.
H2 suction flow rate is nearly constant at 310 L/m.
Outlet H2 is released through a back-pressure regulator, in this case set at the 2nd stage pressure of 210 psia.
Hydride beds are alternately heated or cooled every 50 seconds by a timer.
During integrated FBMR-MHC operation, H2 suction pressure was sub-atmospheric and varied between 8 and 14 psia.
MHC Test 3-10-09
0
100
200
300
400
500
600
5500 5600 5700 5800 5900 6000
Time (s)
Out
let P
ress
ure
and
Flo
w
0
1
2
3
4
5
6
7
8
9
10
Inle
t Pre
ssur
e (p
sia)
Cycle A/B
Inlet Flow l/m
H2 P OUT psia
H2 P IN psia
FBMR & MHC 3-17-09
0
50
100
150
200
18000 18100 18200 18300 18400 18500
Time (s)
Wat
er T
emp
(C)
-5
0
5
10
15
H2
P IN
(psi
a) Cold Water T (C)Hot Water T (C)Timer Hot to AH2 P IN (psia)
March 2010 AIChE Spring Meeting13
Cost Analysis
Using DOE’s H2A analysis for 430 barg H 2 station
• H2A Efficiency (vs. DOE “standard”)– Production efficiency 71% (vs. 63%)– Compression efficiency 75% (vs. 94%)
• Significant MHC efficiency gains possible with improved heat integration or with source of waste heat
– Overall system efficiency of 59% (vs. 62%)• Cost of H2
– $7.98/kg for 100 kg/d, 200 units/year– $3.30/kg for 1,500 kg/d, 200 units/year
• $3.50/kg for “standard” system, 500 units/year)
• Main cost items identified– Longevity of membranes (replacement costs)– Membrane thickness (25 � 15 µm)
March 2010 AIChE Spring Meeting14
Conclusions / Future Work
• Project accomplishments are generally positive • Field test of FMBR and MHC revealed specific paths to achieve predicted
benefits of integration• H2A for integrated system projects competitive H2 cost
Work continues• Two key issues need be addressed before proceeding to the Advanced
Prototype– Improved reliability of hydrogen purity from membranes – Hydride heat exchanger tube integrity
• Prepare skids for future tests– Run both systems independently to confirm issue resolution and then re-run
integrated system
• Finalize design for next generation system (50 Nm3/h)– Optimize heat integration between reformer and MHC to improve overall system
efficiency– Design for manufacture
March 2010 AIChE Spring Meeting15
Thank You!
• Acknowledgements– Funding from the US Department of Energy– Support from NORAM Engineering and Constructors Ltd.
• More Info? Contact us:– MRT: Tony Boyd ([email protected])– Linde: Satish Tamhankar ([email protected])– Ergenics: David DaCosta ([email protected])