2+ - 3 3 2 2 Mg + 2 HCO MgCO + CO + HO Step 3: + 2+ 3 2 5 4 2 2 Mg Si O (OH) + 6 H 3 Mg + 2 SiO + 5 H O Step 2: - + 2 2 3 3 (g) CO H CO HCO + H Step 1: Adsorption CCUS within Energy Systems Mineral Carbonation Absorption Separation Processes Laboratory – Prof. Marco Mazzotti Institute of Process Engineering, ETH Zurich www.ipe.ethz.ch CO 2 Capture and Storage at SPL Climate change mitigation requires a net-zero-CO 2 world, where we need to implement renewable energy sources, to capture CO2 and then either store it or re-use it. The implementation of renewable energy sources requires different energy storage technologies to deal with short- and long-term generation dynamics. 1. L-economy 3. L-economy w/ CCS 2. L-economy w/ CCU 5. O-economy w/ CCU 6. O-economy w/ DAC-CU 7. O-economy w/ bio-energy 8. NET-economy w/ bio- energy and CCS: BECCS 9. NET-economy w/ DAC and CS: DACCS positive CO 2 emissions negative CO 2 emissions net-zero CO 2 emissions 4. L-economy w/ DAC-CS Fossil (reduced) carbon Oxidized carbon (CO 2 ) Synthetic (reduced) carbon Biogenic (reduced) carbon Renewable energy source CO 2 in the atmosphere Distributed CO 2 emissions CO 2 conversion plant Direct air capture of CO 2 from air (DAC) Biomass treatment plant Managed biomass growth Post-combustion CO 2 capture (PCC) Underground CO 2 storage Point source CO 2 emissions Optimization tool determining the optimal design and operation of the H 2 supply chain to minimize cost and/or CO 2 emissions while satisfying a given H 2 demand. 20 40 60 80 100 Round-trip efficiency [%] Flywheel Battery Pumped hydro CAES P2H 2 P2CH 4 Characteristic storage time minutes hours days to weeks weeks to months Zurich We aim at developing novel system paradigms and optimization techniques for the assessment of several decarbonization options from a system perspective. Magnetic Suspension Balance Measuring adsorption isotherms for pure components and gas mixtures Adsorption Equilibria CO 2 on Activated Carbon Adsorption Kinetics TI PI TI TI PI Column TI TI TI Vent TIC 110 cm 85 cm 60 cm 40 cm 10 cm TI Breakthrough experiments Investigation of mass and heat transfer Modeling Adsorption Processes Simulation Toolbox Experimental validation 2-column Fixed-Bed Lab-scale setup for operation of cyclic adsorption processes: Pressure swing, PSA Temperature swing, TSA Vacuum swing, VSA Optimization Non-Convex Multi-Objective Optimization Maximization of the process performance under a set of non-linear and non-convex constraints Sensitivity analysis Optimization result Numerical resolution of system of NPDAEs until cyclic steady state Carbon-free Fuel CO 2 -free flue gas Pre-combustion CO 2 capture Post-combustion CO 2 capture Pressure (PSA) or Vacuum-Pressure (VPSA) Swing Adsorption processes Temperature Swing Adsorption (TSA) Processes CO 2 capture from a moist N2/CO2 mixture which contains impurities Separation of CO 2 , integrated with H 2 - purification. H2 is produced to be used as carbon-free fuel A change in pressure (range: 0-30 bar) drives the regeneration of the sorbent CO 2 Waste (N 2 ) Dry feed Adsorption Heating Cooling time Rinse Purge Sorbent regeneration is allowed for by recovered waste heat (up to 150°C) H 2 purification PSA plant, Linde North America • Classical absorption process with recycle between absorber and desorber • CO 2 uptake capacity limited by solid formation (NH 4 HCO 3 ) • Solid handling section introduced • Solid formation (NH 4 HCO 3 ) exploited to make CO 2 capture less energy intensive Direct Air Capture DAC Vacuum-Temperature Swing Adsorption (VTSA) Processes CO 2 separation from air recovering waste heat or exploiting renewable heat sources Distributed capture Technology Production of pure CO 2 stream for direct utilization DAC units, Climeworks Air Adsorption-based Processes development: Challenges Characterization of new adsorbent materials and definition of optimal adsorbent specifications Optimization of process design for maximum efficiency Technology scale-up Characterization of multi-component competitive adsorption, hysteresis and non-idealities 20 40 60 80 100 Contributions to round-trip efficiency of P2CH 4 [%] Electricity input Electricity output Electrolysis losses DAC losses Fuel synthesis losses Fuel convers. losses Rate-based model development Model-based process design and development Thermodynamics Trans Phenom & Kin Synthesis Optimization Integration CO 2 comp Auxiliaries Cooling Chilling Reboiler CO 2 desorber Other reboilers Steam generation Heat recovered from the cement plant and integrated in the CAP Liquid Chilled Ammonia Process (L-CAP) Controlled Solid Formation Chilled Ammonia Process (CSF-CAP) Mineral carbonation in a nutshell Recycling of concrete waste RCA Mineral Carbonation Mineral Carbonation CO 2 CO 2 C- RCA Sand CaCO 3 Accelerated carbonation Concrete recycling Crushing Iron removal Classification Iron Decentralized concrete recycling Kiln Fuel Clinker 1 Mt 0.84 Mt CO 2 Mill Cement 0.55 Mt CO 2 0.29 Mt CO 2 Cement plant Infrastructure 0.05 Mt CO 2 Additions CaCO 3 + SiO 2 1.6 Mt Air Concrete plants Gravel Concrete Sand Water Decentralized concrete manufacturing Centralized cement manufacturing Concrete fines 0.05 Mt CO 2 • Cement manufacturing is responsible for approx. 6% of the global CO 2 emissions • Lack of foreseeable alternative for cement and for its manufacturing process • 2/3 of the CO 2 stems from the raw material (limestone) • Recycling of concrete waste can store CO 2 and avoid the calcination of new limestone