technologies and approaches of co2 capture
TRANSCRIPT
Southwest Regional Partnership Project
Technologies and Approaches of CO2Capture
Liangxiong Li, Brian McPherson, Robert Lee
Petroleum Recovery Research CenterNew Mexico Institute of Mining and Technology, Socorro, NM 87801
AcknowledgementAcknowledgement
DOE: Southwest Regional Partnership on Carbon Sequestration, Phase II.
DOE: Funding through the NPTO in NETL under Contract No. DE-FC26-00BC15326.
Specific Feature of CO2 Capture from Power Plant.
Reviews of Technologies for CO2 Capture– Characteristics of absorption and adsorption based separations– Membrane separation technologies– State-of-the arts separation technologies– Current status of CO2 capture
Our Approach– Cost-effective CO2 capture from flue gas by produced water extraction– Zeolite membranes– Hydrotalcite–zeolite composite membranes
Conclusions
OutlineOutline
1. Specific Feature of CO1. Specific Feature of CO22 Capture from Capture from Power Plant Power Plant
Post-combustion
Pre-combustion
1.1 Typical CO1.1 Typical CO22 Concentrations in Process Streams? Concentrations in Process Streams?
Power plant CO2 concentration, vol/%
Power Plant Flue Gas, Post-combustion CO2 capture
Coal fired boiler 14
Natural gas fired boiler 8
Natural gas combined cycle 4
IGCC, Pre-combustion CO2 capture
Coal gasfication 40
Natural gas oxidation 24
Others
Blast furnace gas 20-27
Oil refineries and petrochemical plant 8
Thambinmuthu et al., 2002
2. Reviews of Technologies for CO2. Reviews of Technologies for CO22 CaptureCapture
Technologies Advantages Challenges
Aqueous chemical absorbents Mature technology High COE and corrosion
Glycol (Selexol) Commercial product High COE and require low T
Aqueous ammonia High-value byproduct Low T requirement (80 oF)
Metal organic frameworks High capacity Expensive and high sensitivity
Ionic liquid High T and capacity Expensive and high viscosityAbs
orpt
ion
Bas
edM
embr
ane
Bas
ed H2 selective membrane Favorable for W|GS High pressure operation
Pd metal membrane High separation factor High cost and sensitivity
Zeolite membrane Molecular sieve Sensitive to H2O vapor
Lithium oxide membrane High temperature Low separation factor
{Others Hydrates High pressure operation Low T, High viscosity
Hybrids process High-value by product Low capacity
2.1 Characteristics of Absorption and Adsorption 2.1 Characteristics of Absorption and Adsorption
Flue gasCO2
Scru
bber
Reg
ener
ator
1. Chemical absorption2. Physical absorption3. Solid Physical adsorption
Regeneration
• High capacity• Low regeneration temperature• Low solvent circulation rate• Low solvent degeneration rate, 0.35-2.0 kg/ton CO2• Low corrosion rate
2.2 Membrane Separation Technologies2.2 Membrane Separation Technologies
1. CO2 selective membranes2. Membranes reactor for CO
shift and H2/CO2 separation
Polymeric-metallic, LANL
Polymer, INEELAlumina, ORNL
Pd membrane, LANL
H2 ionic transport O2 ionic transport, pervoskite, Eltron
CO2 ionic transport
Silica membrane, ECN
Zeolite membrane, Univ. of Cincinnati,
SNL
Solution-diffusion Adsorption-diffusion Ionic diffusion
H2 (CO2)
CO2 (H2)
2.3 State2.3 State--ofof--the Arts Separation Technologies the Arts Separation Technologies
1. Aqueous Chemical Sorbents2. Glycol (Selexol)3. Aqueous Ammonia4. Metal Organic Frameworks
T=200 oCP=15 Psi
N2 (~70%), CO2 (~12%)Contaminant, <1%
Post-combustion
High-temperature membranes(1) polymeric-metallic membranes(2) porous ceramic membranes(3) ionic conductive membranes
Ionic liquid
T=400 oCP=950 Psi
H2 (~60%), CO2 (~40%)
Pre-combustion
2.4 Current Status of CO2.4 Current Status of CO22 Capture Technologies Capture Technologies
COCO22 capture by chemical absorption is a commercial process. Currentcapture by chemical absorption is a commercial process. Current research research focuses on:focuses on:
–– Modification of conventional chemical absorbent to enhance the cModification of conventional chemical absorbent to enhance the capture capacity and apture capacity and reduce the regeneration energy.reduce the regeneration energy.
–– Development of novel type of absorbent and adsorbent including iDevelopment of novel type of absorbent and adsorbent including ionic liquid and onic liquid and metal organic framework.metal organic framework.
–– Design more efficient contactor for high CODesign more efficient contactor for high CO22 capture capacity and low energy capture capacity and low energy consumption.consumption.
Membrane technology for COMembrane technology for CO22 capture is under development, especially for high capture is under development, especially for high temperature COtemperature CO22 separation.separation.
–– PolymericPolymeric--metallic composite membranesmetallic composite membranes
–– Molecular sieve Molecular sieve zeolitezeolite membranes membranes
–– Ionic conducting membranesIonic conducting membranes
–– Hydrotalcite/zeoliteHydrotalcite/zeolite composite membranescomposite membranes
3. Our Approach 3. Our Approach
1. Integrated system for cost-effective CO2 capture by produced water extraction
2. Molecular sieve zeolite membranes
3. Hydrotalcite––zeolite composite membranes
3.1 Cost-Effective CO2 Capture from Flue gas by Produced Water Extraction
CO2 bubbles after depressured
0%
2%
4%
6%
8%
10%
12%
14%
Mol
e fra
ctio
n of
CO
2 , % DI water
Produced water
Inlet gas Outlet gas
>96.7%
3.2 High Temperature CO3.2 High Temperature CO22 Separation by Separation by MicroporousMicroporousInorganic Membranes Inorganic Membranes
Current status:
1) Polymeric membranes, T<150 °C. (Lin et al., 2006, Science)
2) Polymer-metallic composite membranes, relative low flux and unknown high pressure separation performance.
3) Inorganic membranes, low separation factor. (Chung et al., 2005)
Requirements for novel inorganic membranes:
1) Pore diameter < 1 nm to inhibit Knudsen diffusion and increase the selectivity.
2) Preferential CO2 adsorption to maximize the permeability and selectivity.
H2: 0.283 nmN2: 0.380 nmCO2: 0.399 nmCO: 0.394 nm
2 µm
3.3 3.3 ZeoliteZeolite Membranes Membranes
MFI
FAU
+
Molecular sieve zeolites:Crystal: excellent chemical, mechanical, and thermal stabilities.Sub-nanometer pores suitable for molecular separation.
Pore dia. ~ 0.56 nm
2 µm
feedii
permeateiii xx
xxS
)]1/([)]1/([
−
−=
Pore dia. ~ 0.74 nm
MFIMFI--Type Type ZeoliteZeolite Membranes Membranes
2 µm
Substrate
Zeolite layer
1 µm
0
2
4
6
8
10
12
14
16
0 100 200 300 400
Temperature, oC
Perm
eanc
e, 1
0-8 m
ol/m
2 .s.P
a
0
5
10
15
20
25
Sepa
ratio
n fa
ctor
(SF)
CO2
N2
SF
dpd
rANDP
Ass
θλ
ε2=ZSM-5 (MFI) membrane
Pore size 0.56 nm
FAUFAU--Type Type ZeoliteZeolite Membranes Membranes
1 µm
NaY (FAU) membranePore size 0.74 nm
2 µm
Tubular and disc membranesTubes: Pall Corp.
COCO22 Separation by Separation by ZeoliteZeolite MembranesMembranes
T=25 ° C: αCO2/N2= ∼ 60, Ps=∼10-8 mol/m2.h.Pa
1. Separation factor decreases with increase of temperature
2. Separation factor and gas permeance decrease at existence of water vapor
3.4 3.4 HydrotalciteHydrotalcite––ZeoliteZeolite Composite MembranesComposite Membranes
500 nm
Zeolite nucleation Clay coating
1 µm Clay/zeoliteMembrane
Characteristics of Characteristics of HydrotalciteHydrotalcite Composite MembranesComposite Membranes
Cross-Section of SEM Image TEM Image
Characteristics:(1) High CO2 absorption capacity at temperature above 400 oC(2) Enhanced CO2 chemical absorption at existence of water vapor
4. Conclusions4. Conclusions
CO2 can be captured using existing technologies and deep reduction in gas emission can be achieved. The challenges include:
– High operation cost, 32-40 $/t CO2
– No full-scale demonstration for deep understanding and accurate evaluation
Near term plan includes integrated system for economical CO2 capture and modification of conventional technologies for efficient and cost-effective separations.
Long term plan focuses on the novel material and process developments,– Polymer metallic composite membranes
– High temperature microporous ceramic membranes
– Metal organic frameworks
– Ionic liquids for high temperature IGCC