Hydrogen production with integrated CO2 capture in a...

Hydrogen production with integrated CO2 capture in a novel membrane assisted Chemical switching reforming (CSR) reactor

1 Chemical Process Intensification, Department of Chemical Engineering and

Chemistry, Eindhoven University of Technology, The Netherlands

2 Energy & Process Engineering, Norwegian University of Science and

Technology, Norway

Solomon A. Wassie1,2, Jose A. Medrano1, Fausto Gallucci1,

Martin van Sint Annaland1

2

OUTLINE Introduction

The Chemical Switching Reforming (CSR) concept

Results

Conclusions

TU e Technische Universiteit Eindhoven University of Technology

3 TU e Technische Universiteit Eindhoven University of Technology

Motivation

Fossil fuels are the basis of the primary energy worldwide

Projections indicate a growth in the use of fossil fuels in the coming decades

70 % fossil

Primary energy

90 %

0

5

10

15

20

25

30

1970 1980 1990 2004 2020 2050

10

9 t S

KE

Renewable energies

Water power

Natural gas

Oil

Coal

Nuclear power

World wide consumption of primary energy (Source: BP (2003), World Energy Council).

Introduction CSR concept Results Conclusions Why environment and fossil fuel/ combustion?


Motivation • At present world wide consumption of primary energy1 is about 1.7.1010 t SKE ! (for

2050: more than 2.5.1010 t SKE).

• More than 90% of primary energy at present is provided by fossil fuels (for 2050: more than 70%).

• Based on coal this amounts to a mass of about 1.5.1010 t per year.

• Based on 0.01 € per kWh this amounts to a cash flux of approximately 1.2.1012 € per year.

• World economy to a large part is dominated by energy markets!

• Fossil fuels are converted to secondary (final) energy exclusively by combustion.

• Products of combustion: CO2, NOx, other local poluttants

• CO2 is the main gas affecting the climate change!!!

Combustion has large impact on environment, daily life, economy!

Introduction CSR concept Results Conclusions


60

55

50

45

40

35

30

25

20

15

10

5

0

2010 2015 2020 2025 2030 2035 2040 2045 2055

GtC

O2

Year

CCS 19 %

Renewable 17 %

Nuclear 6 %

Power generation

efficiency and fuel

switching 5 %

End-use fuel switching

15 %

End-use fuel and

electricity efficiency 15 %

BLUE map emissions 14 Gt

Baseline emissions 57 Gt

WEO 2009 450 ppm case ETP 2010 analysis

Air

N2

Fuel

CLC: CO2 + H2O

CLR: CO + H2

Me

MeO

The IPCC mitigation strategies:


THE ENERGY IN THE FUTURE

Chemical looping is one of the most promising technology among CCS strategies.

CO2 free technology

Kaya equation (Impact =Population xAffluence xTechnology) (translated to CO2 emmision)

CO2 Emission = CO2/energy x [ energy/product x GDP/person] x population

Goal: Reduction by

50% until 2050

Increase by a factor of 1.5

(IPCC 2000) Increase by a factor of 1.65

(1% growth per year)

Decrease by a factor of 0.4

(-1.8% per year, alternative

scenario IEA 2004)

“CO2-free”

technologies?

Reformed Syngas

Reformer and

Furnace

EX01.A

HT-WGS

PSA

Steam

Cycle

Pre

-RE

F

S-removal

H2 to de-S

Air

NG

Pure H2PSA-offgas

H2O to process

Gas stack

steam-to-export


THE H2 PRODUCTION… Hydrogen production with integrated CO2 capture is a promising technology

in terms of process efficiency.

More than 80% is produced by Steam Reforming (SR) of natural gas/methane in multi-tubular fixed-bed reactors.

CH4 + H2O ↔ CO + 3H2

ΔH°298K = +206 kJ/mol; 800-1000 ℃; 20-35 atm

CO + H2O ↔ CO2 + H2

ΔH°298K = -41 kJ/mol; 200-400 ℃

1 Highly endothermic and

equilibrium limited reaction

system

2 Process is efficient only at

very large scale.

4 CO2 emissions


3 Large number of downstream processing steps decreases the system efficiency

7

DepletedAir

H2

CO2 + H2O

CH4 + H2O

Air

Air r

eacto

r

Fuel re

acto

r

Hot MeOH2 perm-selective membranes

MeO/N2 separation

1

2

3

4

CH4 + H2O ↔ CO + 3H2

ΔH°298K = +206 kJ/mol

CO + H2O ↔ CO2 + H2

ΔH°298K = -41 kJ/mol

1 Autothermal process can be achieved by

adjusting the circulation rates

2 Mixing of N2 with CO2 is avoided

3 Pd-based membranes for selective H2

separation leading to conditions beyond

the thermodynamic equilibrium

4 Pure H2 through the membranes

CO2 capture (easily separated from

steam) from the fuel reactor

However pressurized interconnected

reactors is a technology not developed and

represents technological challenges


THE MEMBRANE-ASSISTED CHEMICAL LOOPING REFORMING CONCEPT

How can we avoid the use of interconnected reactors??



THE MEMBRANE-ASSISTED CHEMICAL LOOPING REFORMING CONCEPT

High pressure operation


Increase the diving force across the membrane = reduce the amount of membrane surface area required for a given fuel throughput

Deliver a high pressure CO2 stream for efficient compression, transport and storage

Allow more homogeneous fluidization with better mass transfer rates

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9

1 Autothermal process can be achieved by

adjusting the circulation rates

2 Mixing of N2 with CO2 is avoided

3 Pd-based membranes for selective H2

separation leading to conditions beyond

the thermodynamic equilibrium

4 Pure H2 through the membranes

CO2 capture (easily separated from

steam) from the fuel reactor


THE CHEMICAL SWITCHNING REFORMING CONCEPT Depleted Air

H2

CO2 + H2O

CH4 + H2OAir

H2 perm-selective

membranes

5 Possibility to work at high pressures

Scaling up of the reactor is simplified

1

2

3

4

5



THE EXPERIMENTAL SETUP

AIR

N2

CH4

H2O

T

H2P

P

P

P

T

T

GA

Vent

P

FM

Drain Process water

T

T

T

T

T

P

P

P Gas pressure regulator (manual)

Butterfly valve (open-close)

Needle valve

Massflow controller

3 way valve

PPressure sensor

Temperature sensor

Temperature regulator

Heat band power controller

Control computer

Condensor

FM Permeate flow meter

Gas analyzer

Particle filter

Pd - membrane

Vacuüm pump

Heat exchanger

Process equipment

Material flow

Process water

Measurement data

Command data

Thermal flow

Tracer

Condensate vessel

Flow characteristics Process control

Pressure relief valve

Inslutaion

Chemical

Material source/outlet

Instruments & sensors

T

GA

T

10 cm

3.5 cm

Top view (membrane configuration)


Catalyst: Ni/Al2O3 (37% weight) dp= 0.1-0.2 mm Permeate at vacuum conditions Oxidation time: 2-8 min Oxidation : reduction = 1:2


MEMBRANES and Exp. CONDITIONS

4 Pd-Ag metallic supported 13 cm length 1 cm diameter Permeance: 1*10-6 mol/s/Pa/m2

Ideal perm-selectivity > 11.000

Configuration T [°C] u0/umf P (Bar) Overall Oxygen to

Carbon ratio S/C ratio

FBMR 425-600 3-5 1-4 - 2-3

CSR 450-550 3-5 1-4 0.5 2-3

X5000 5μmb) X5000 5μmc)

X1000 10μma)

Hastelloy X support

Ceramic barrier layer

Pd-Ag layer

4.12 μm5.00 μm 4.68 μm 4.36 μm 4.32 μm

Hastelloy X support


Pd-Ag layer



EXPERIMENTAL DEMONSTRATION Conventional SMR in FBMR

Experimental conditions • P= 4 bar • T= 470 oC • S/C = 3 • U0= 3Umf [m/s]

0

20

40

60

80

100

0

5

10

15

20

25

30

0 500 1000 1500 2000 2500 3000

CH

4convers

ion (

%)

Rete

nta

te c

om

po

sitio

n (

Vo

l%)

Time (s)

CO CO2 CH4

H2 XCH4

No H2 extraction With H2 extraction


The selective extraction of H2 through the membranes displaces the equilibrium towards products

Typical test measurement


EXPERIMENTAL DEMONSTRATION Conventional SMR in FBMR


0

10

20

30

40

50

60

70

375 425 475 525 575

CH

4 c

on

ve

rsio

n (

%)

T (°C)

FBMR FBMR

FBR FBR

Influence of temperature at 1.6 bar

Thermodynamic equilibrium calculated in Aspen Plus ®

Deviations associated to a combination of changed hydrodynamics and kinetics limitations

Better understanding of the FBMR concept… Time for the Chemical Switching Concept


EXPERIMENTAL DEMONSTRATION CHEMICAL SWITCHING REFORMING


470

490

510

530

550

570

590

0 1000 2000 3000 4000 5000 6000 7000

Re

ac

tor

tem

pera

ture

(0C

)

Time (s)

Typical test measurement

Experimental conditions • P= 3 bar • T= 550 oC • S/C = 3 • U0= 3Umf [m/s] • Oxidation:reduction = 1:2 • Oxidation time = 6 min • Adiabatic conditions

• Autothermal operation is demonstrated • Hydrogen Recovery > 25% • Separation factor > 30%

0

5

10

15

20

25

30

35

40

0 1000 2000 3000 4000 5000 6000 7000

Rete

nta

teco

mp

osit

ion

Vo

l (%

)

Time (s)

COCO2CH4H2

No membranes With membranes


EXPERIMENTAL DEMONSTRATION CHEMICAL SWITCHING REFORMING


0

5

10

15

20

25

30

35

40

45

50

1 2 3 4 5 6 7 8 9

CH

4 c

on

ve

rsio

n (

%)

Oxidation time (min)

MAGSR GSR

MAGSR GSR

0

10

20

30

40

50

60

70

80

0 0.2 0.4 0.6 0.8 1Te

mp

era

ture

rise

pe

r cycle

(0C

)

Normalized time (-)

Influence of oxidation time at 1.6 bar and Tend 475 0C Oxidation : reduction = 1:2

Influence of oxidation time at 1.6 bar and Tend 485 0C on the autothermal stability Oxidation : reduction = 1:2

Main outcomes: Deviation between thermodynamics and experiments associated to slow gas-solid reaction for

reduction of the NiO into free Ni for the catalytic reforming reaction There is an optimum in oxidation temperature


POST-MORTEM CHARACTERIZATION

Hastelloy X Ceramic barrier

Pd-Ag layer

X5000 5μmb) X5000 5μmc)

X1000 10μma)

Hastelloy X support


Pd-Ag layer

4.12 μm5.00 μm 4.68 μm 4.36 μm 4.32 μm

Hastelloy X support


Pd-Ag layer

Ideal perm-selectivity > 11.000

After use ideal perm-selectivity: 150

Fresh membrane

Formation of PdO on top of the Pd layer

Delamination of the Pd layer because of thermal cycles


17

CONCLUSIONS

CHALLENGES Redefine the concept configuration to limit membrane exposure to oxygen

Improve existing membranes with higher thermal and mechanical resistance to

oxidative atmospheres

The CSR allows the use of pressurized conditions easier than other concepts

and combines advantages of Chemical Looping technology and membrane

reactors, where pure H2 can be achieved accomplishing CO2 capture

Autothermal operation can be obtained by switching the feed periodically

The oxygen carrier reduction limits methane conversion and hydrogen recovery

The membranes were not able to withstand the continuous oxidation/reduction

cycles with corresponding thermal cycles

The reactor concept has been proven by the first time, although more research is

needed



18

Contact us at

[email protected]

[email protected]

[email protected]

[email protected]

TU e


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