A High Efficiency, Ultra-Compact Process For Pre-Combustion CO 2 - PowerPoint PPT Presentation

A High Efficiency, Ultra-Compact Process For Pre-Combustion CO 2 Capture DE-FOA-0001235 • Professor Theo Tsotsis, University of Southern California, Los Angeles, CA • Professor Vasilios Manousiouthakis, University of California, Los Angeles, CA • Dr. Rich Ciora, Media and Process Technology Inc., Pittsburgh, PA U.S. Department of Energy National Energy Technology Laboratory Office of Fossil Energy 1 November 16, 2015

Presentation Outline • Project Objectives • Process Description – Background – Project Technical Approach – Advantages – Challenges • Progress to Date on Key Technical Issues • Scope of Work • Tasks to be Performed 2

Project Objectives Overarching Project Objectives: 1. Prove the technical feasibility of the membrane- and adsorption-enhanced water gas shift (WGS) process. 2. Achieve the overall fossil energy performance goals of 90% CO 2 capture rate with 95% CO 2 purity at a cost of electricity of 30% less than baseline capture approaches. Key Project Tasks: 1. Design, construct and test the lab-scale experimental MR-AR system.----- USC 2. Select and characterize appropriate membranes, adsorbents and catalysts.----- M&PT, USC Develop and experimentally validate mathematical model.----- UCLA, USC 3. 4. Experimentally test the proposed novel process in the lab-scale apparatus, and complete the initial technical and economic feasibility study. (Budget Period 2) .----- M&PT, UCLA, USC 3

Background Conventional IGCC Power Plant 4

Background, cont. Hybrid Adsorbent Membrane Reactor (HAMR)  The HAMR combines adsorbent, catalyst and membrane functions in the same unit. Previously tested for methane steam reforming (MSR) and the WGS reaction.  The simultaneous in situ removal of H 2 and CO 2 from the reactor significantly enhances reactor yield and H 2 purity. CO 2 stream ready for sequestration . 5

Background, cont. CMS Membranes for Large Scale Applications M&PT test-unit at NCCC for hydrogen separation CMS membranes and modules 6

Background, cont. Hydrotalcite (HT) Adsorbents & Co/Mo-Based Sour Shift Catalysts Hydrotalcite Adsorbent:  The HT adsorbents shown to have a working CO 2 capacity of 3-4 wt.% during the past HAMR studies with the MSR and WGS reactions. Theoretical capacity >16 wt.%. Co/Mo-Based Sour Shift Catalyst:  A commercial Co/Mo-based sour shift catalyst has been used in our past and ongoing lab-scale MR studies (P<15 bar) with simulated coal-derived and biomass-derived syngas. Shown to have stable performance for >1000 hr of continuous operation. 7

Project Technical Approach Proposed Process Scheme  No CGCU (or WGCU) step is required to clean-up the syngas prior to entering the WGS reactor.  No post-treatment absorption step is needed to separate the H 2 from CO 2 .  No CO 2 recompression step is needed for its further transport and storage.  Note that the use of 2 HT/AR is for illustrative purposes only. The full process will require more (typically 4) HT/AR in use. 8

Project Technical Approach, cont. Proposed MR-AR Process  Potential use of a TSA regeneration scheme allows the recovery of CO 2 at high pressures.  The MR-AR process overcomes the limitations of competitive singular, stand-alone systems, such as the conventional WGSR, and the more advanced WGS-MR and WGS-AR technologies . 9

Advantages Our Proposed Process vs. SOTA Key Innovation: • Highly-efficient, low-temperature reactor process for the WGS reaction of coal-gasifier syngas for pre-combustion CO 2 capture, using a unique adsorption-enhanced WGS membrane reactor (MR- AR) concept. Unique Advantages: No syngas pretreatment required: CMS membranes proven stable in past/ongoing studies to all of • the gas contaminants associated with coal-derived syngas. • Improved WGS Efficiency: Enhanced reactor yield and selectivity via the simultaneous removal of H 2 and CO 2 . • Significantly reduced catalyst weight usage requirements: Reaction rate enhancement (over the conventional WGSR) that results from removing both products, potentially, allows one to operate at much lower W/F CO (K gcat /mol.hr). Efficient H 2 production, and superior CO 2 recovery and purity: The synergy created between the • MR and AR units makes simultaneously meeting the CO 2 recovery/purity targets together with carbon utilization (CO conversion) and hydrogen recovery/purity goals a potential reality. 10

Challenges Key Technical Challenges Ahead (BP1): • Modify an existing lab-scale test unit at USC to permit operation at higher pressure (up to 25 bar). • Design and incorporate a dedicated AR subsystem. • Prepare and characterize membranes and adsorbents and validate their performance at the relevant experimental conditions. • Validate catalyst performance at the relevant pressure conditions. Verify applicability of global reaction kinetics. • Develop and experimentally validate mathematical model. 11

Challenges, cont. Proposed Lab-Scale Experimental System 14 3 Modify an existing MR system at USC (up to 25 bar) 13 12 3 12 4 9 8 2 8 10 1 4 5 7 11 15 7 10 2 9 1 5 Adsorption 8 15 6 8 10 2 15 1 5 9 10 15 7 11 12 2 4 8 7 1 Regeneration 10 9 8 3 4 12 13 3 14 Incorporate a dedicated AR subsystem 12

Membrane Reactor Multi-scale (Pellet-Reactor Scale) Model 2D Representation of control volumes in Membrane Reactor 1D Representation of control volumes in Membrane Reactor 13

Membrane Reactor Multi-scale (Pellet-Reactor Scale) Model 1D (pellet radial direction) pellet equations solved at each grid point of the discretized reactor domain (z axis). 14

Pellet-Scale Steady-State Model j-Component Mass Conservation: (  )   ( ) = ρ − ε − ε ∇⋅ = B C . . p p p 0 M r 1 j j 1, N j j s V A f j , s        ( ) surface = r r x x at S rate of mass generation of j rate of addition of mass of f j , f j , 0 by reaction per pellet volume jby diffusion per pellet volume Dusty-gas model (DGM) :                      p  p i x 1 m B x 1 ∑ −∇ =  + ∇  + −   j p p p p p p Tot o i m j x P  j j    γ ( ) ( ) f j , f j , f j , f f j , f i , ε     M 4 d p   3 3   π π RT   3 p 3 p 1 ε 2 k T m ε 2 k T m f   j   pore  V  3 3 B ij B ij   τ π  V   V    3 2 M τ πσ Ω τ πσ Ω   2 (1,1)*   2 (1,1)*    i  16 p 16 p  ji ji ji ji         eff D iK   eff eff D D ij ij Energy Conservation:    ( )       N ( ) 1 ∑ s    = ∇ − ε + ε ∇ − ε ∇⋅  B C . . p p p p p p p p 0 . 1 k k T h j     A s A f A f j , f j ,     M   ( ) = j 1 surface j =     p p T T at S rate of energy addition by heat conduction 0 per volume rate of energy addition by species mass fluxes per volume 15

1-D Reactor-Scale Steady-State Model Total mass conservation:   ( )   = ε ∇⋅ ρ r r 0 v A f f B C . .   ( )   ( ) Momentum conservation: = = R R r r v v , P P at S , f f 2 in ( ) ( ) in   2 − ε − ε       r r   1 1     ∇ = − V − µ V ρ r r r r r ∇ = P 150 1.75 v v  R ( ) ( ) v 0 at S and S   f f f f 3 3 ε ε f 3 4 r 2 r d d   rate of pressure drop V p V p     inside reactor drag exerted by the fluid on the solid surface per volume j-Component Mass Conservation: (  )   ( )   η ρ − ε − ε ∇⋅ − r r r M r 1 j   j j j s V A f j ,     . . B C   rate of production of mass of ( ) net rate of addition of mass of   j by reaction per volume = ) (   ) r r jby diffusion per vo lume ≠     ( x x at S   0 if j H f j , f j , 2 ε ∇ ⋅ ρ = λ = 2 r r r     in   x v , E − = A f j , f f j  a    B exp 1 if j H       λ ⋅ ( ) 2 H o   2 r R T  − −  j n n net rate of addition of mass of P P j by convection per volume δ H r H p   R 2, 2,     mem     rate of addition of mass of j by permeation per volume 16