MODEL-DERIVED CHEMICAL-LOOPING SYSTEM DESIGNS George M. Bollas - PowerPoint PPT Presentation

MODEL-DERIVED CHEMICAL-LOOPING SYSTEM DESIGNS George M. Bollas Department of Chemical & Biomolecular Engineering University of Connecticut http://pdsol.engr.uconn.edu 04/04/2014 1/37 IASE Seminar Series

About Diploma in Chemical Engineering Aristotle University of Thessaloniki – Greece Ph.D. in Chemical Engineering Aristotle University of Thessaloniki – Greece Postdoc in Chemical Engineering Massachusetts Institute of Technology – USA Assistant Professor University of Connecticut NSF CAREER Award 2011 ACS-PRF DNI Award 2013 >$2M in research grants in 2010-2013 9 graduate researchers 10 undergraduate researchers 04/04/2014 2/37 IASE Seminar Series

Research Group (PDSOL) Enabling emerging energy technologies via integration of modeling with experimentation of processes lacking fundamental understanding Catalysis for renewable fuels Process Design, Scale-up & Control Novel spouted-bed reactor for biomass Dynamic simulation & optimization thermochemical processes (pyrolysis, Optimal experimental design gasification, chemical-looping combustion) Model-assisted scale-up based on dynamic Comprehensive catalyst characterization and sensitivity analysis catalyst activity dynamic simulation Chemical-looping combustion & reforming Char & Catalyst Collection ¢ µ T vent Liquid & Gas Analysis Annulus: Dynamic simulation @C a @t = D @ 2 C a @C a @ ½ + 2 D @C a @ ½ 2 ¡ u ij vent T T ½ ½ Spout: ¡ ¢ @C s @t + @C s u s + 1 2 du s = 0 @z of a spouted bed µ ½ T Catalyst characterization Reactor z (ZSM-5 after pyrolysis) T Liquid Collection Filter T T Flow Meter Gas Analysis FTIR real time analyzer Gas Collection vent N 2 Spouted-bed Fixed-bed reactor developed and simulated in PDSOL. Application Coolant reactor for Auger of Optimal Experimental Design on the laboratory reactor. Scale-up Feeder biomass pyrolysis N 2 based on sensitivity analysis of the bench-scale reactor. 04/04/2014 3/37 IASE Seminar Series

Climate change urgency Carbon capture needs to be deployed to effectively lower the global CO 2 portfolio Fig.1: University of Maine Environmental Change Model (UM-ECM) potential biomes calculated for modern climate. From left to right: input cooled by 4°C; todays input; input warmed by 2.5°C. Note the effect on the arctic sea ice. Data/images obtained using Climate Reanalyzer™ (http://cci -reanalyzer.org), Climate Change Institute, University of Maine, USA. 04/04/2014 4/37 IASE Seminar Series

US-wide CO 2 storage capacity Estimated total storage capacity of over 100 Gt in the continental US 04/04/2014 5/37 IASE Seminar Series

CO 2 Capture Options Back in 2008 Resource: America’s Energy Future Technology And Transformation, Committee On America’s Energy Future, National Academy Of Sciences, National Academy of Engineering, National Research Council of The National Academies, The National Academies Press 04/04/2014 6/37 IASE Seminar Series

Chemical-looping progress Boot-Handford ME, Abanades JC, Anthony EJ, Blunt MJ, Brandani S, Mac Dowell N, et al. Carbon capture and storage update. Energy Environ Sci 2014. 04/04/2014 7/37 IASE Seminar Series

Chemical-looping combustion (CLC) N 2 O 2 CO 2 H 2 O A method for inherent CO 2 separation Oxygen carriers M : metal steam MO : metal oxide water MO Reduction: endothermic CH 4 + 4MO  CO 2 + 2H 2 O + 4M Oxidizer Reducer Oxidation: exothermic M + ½ O 2  MO M Fuel Air Circulating oxygen carrier: active metal oxides (Ni, Cu, Fe, Mn) supported over Al 2 O 3 , MgAl 2 O 4 , NiAl 2 O 4 , YSZ, TiO 2 , ZrO 2 . Reactivity testing: TGA, fixed-bed, interconnected fluidized-beds. 04/04/2014 8/37 IASE Seminar Series

Our work [1] Zhou Z, Han L, Bollas GM. Model-based analysis of bench-scale fixed-bed units for chemical-looping combustion. Chem Eng J 2013;233:331 – 48 . [2] Han L, Zhou Z, Bollas GM. Heterogeneous Modeling of Chemical-Looping Combustion. Part 1: Reactor Model. Chem Eng Sci 2013;104:233 – 249 . [3] Han L, Zhou Z, Bollas GM. Heterogeneous Modeling of Chemical-Looping Combustion. Part 2: Particle Model. Chem Eng Sci 2014;in press. [4] Zhou Z. Han L, Bollas GM. Overview of Chemical-Looping Reduction in Fixed Bed and Fluidized Bed Reactors Focused on Oxygen Carrier Utilization and Reactor Efficiency. Aerosol Air Qual Res 2014;14:559 – 71. [5] Zhou Z, Han L, Bollas GM. Kinetics of NiO reduction by H 2 and Ni oxidation at conditions relevant to chemical-looping combustion and reforming. Int J Hydrogen Energy 2014;in press. [6] Han L, Zhou Z, Bollas GM. Chemical-looping combustion in a reverse-flow fixed- bed reactor. Appl Energy 2014;in review. [7] Zhou Z, Han L, Bollas GM. Model-assisted analysis of fluidized bed chemical- looping reactors. AIChE J 2014;in review. [8] Han L, Zhou Z, Bollas GM. Optimal Experimental Design for Fixed Bed Chemical- Looping Experiments. Comput Chem Eng 2014;in preparation. 04/04/2014 9/37 IASE Seminar Series

The “dream concept” maximize information content of experiments integrate experimentation with reactor design obtain scale- independent process models estimate model parameters that increase the accuracy of process scale-up/scale- down reduce risk of OED for process scaling of chemical-looping: technology scale- Measurements of bench- and pilot- scale processes are used to up/scale-down. develop state/space models. These models are subsequently used to identify time-varying experimental conditions that maximize the statistical significance of the measurements with respect to process scale, subject to constraints. 04/04/2014 10/37 IASE Seminar Series

Fixed-bed model description Oxygen carrier External diffusion Heterogeneous model Bulk particles across film fluid Fluid phase Solid 𝜖𝐷 𝑗 𝜖𝑢 + 𝜖𝐺 𝜖𝑊 = 𝜖 𝜖𝐷 𝑗 𝑗 phase 𝜁 𝑐 𝜖𝑨 𝜁 𝑐 𝐸 𝑏𝑦,𝑗 + 𝑙 𝑑,𝑗 𝑏 𝑤 𝐷 𝑑,𝑗 | 𝑆 𝑞 − 𝐷 𝑗 𝜖𝑨 Furnace wall 𝜖𝑈 𝜖𝑊 = 𝜖 𝜖𝑈 𝜖𝑈 𝜁 𝑐 𝐷𝑞 𝑔 𝐷 𝑈 𝜖𝑢 + 𝐷𝑞 𝑔 𝐺 𝑈 𝜖𝑨 𝜁 𝑐 𝜇 𝑏𝑦 𝜖𝑨 Reactions on 𝑑 | 𝑆 𝑞 − 𝑈 + 4𝑉 +ℎ 𝑔 𝑏 𝑤 𝑈 𝐸𝑆 (𝑈 𝑥 − 𝑈) pore surface Pore diffusion Solid phase Heat conduction 𝜖𝐷 𝑑,𝑗 = 1 𝜖 𝑑2 𝜖𝐷 𝑑,𝑗 𝜁 𝑑 𝐸 𝑓,𝑗 𝑠 + 𝜍 𝑡 𝑆 𝑗 𝜖𝑢 𝑠 𝒅2 𝜖𝑠 𝜖𝑠 𝑑 𝑑 Heat transfer between 𝜖𝑈 packed bed and wall 𝑑 1 − 𝜁 𝑑 𝜍 𝑡 𝐷𝑞 𝑡 + 𝜁 𝑑 𝐷𝑞 𝑑 𝐷 𝑈,𝑑 𝜖𝑢 = Axial dispersion of 𝜇 𝑡 𝜖 𝑑2 𝜖𝑈 𝑑 heat and mass 𝜖𝑠 𝑠 + 𝜍 𝑡 (−𝛦𝐼 𝑗 )(𝑆 𝑗 ) 𝑠 𝑑2 𝜖𝑠 𝑑 Heat conduction through packed-bed Pressure drop Axial convective Tube wall 2 𝑒𝑄 𝑒𝑨 = − 1 − 𝜁 𝑐 𝜍𝑣 0 150 heat + mass + 1.75 transfer in gas 𝜁 𝑐3 𝐸 𝑞 𝑆𝑓 𝑞 Han, L.; Zhou, Z.; Bollas, G. M. Heterogeneous Modeling of Chemical-Looping Combustion. Part 1: Reactor Model. Chemical Engineering Science 2013 04/04/2014 11/37 IASE Seminar Series

Fixed-bed model application Application to experimental data of CLC by Iliuta et al. (2010), Ryden et al. (2008) and CLR data by Jin (2002) Han, L.; Zhou, Z.; Bollas, G. M. Heterogeneous Modeling of Chemical-Looping Combustion. Part 1: Reactor Model. Chemical Engineering Science 2013 04/04/2014 12/37 IASE Seminar Series

Reduction reactions with NiO Δ H ° = 165 kJ/mol CH 4 oxidation CH 4 + 2NiO ↔ 2Ni + CO 2 + 2H 2 Oxygen carrier Δ H ° = -2.2 kJ/mol H 2 oxidation H 2 + NiO ↔ Ni + H 2 O reduction Δ H ° = -43.3 kJ/mol CO oxidation CO + NiO ↔ Ni + CO 2 reactions Δ H ° = 203 kJ/mol Partial CH 4 oxidation CH 4 + NiO ↔ Ni + 2H 2 +CO Δ H ° = 205 kJ/mol Steam reforming CH 4 + H 2 O ↔ 3H 2 + CO Δ H ° = -41.1 kJ/mol Water gas shift CO + H 2 O ↔ H 2 + CO 2 Δ H ° = 247 kJ/mol Dry reforming CH 4 + CO 2 ↔ 2CO + 2H 2 Δ H ° = 88 kJ/mol Methane CH 4 ↔ 2H 2 + C Reactions decomposition catalyzed by Ni Δ H ° = 131 kJ/mol Carbon gasification by C + H 2 O ↔ CO + H 2 steam Δ H ° = 173 kJ/mol Carbon gasification by C + CO 2 ↔ 2CO CO 2 Zhou, Z.; Han, L.; Bollas, G. M. Model-based Analysis of Bench-Scale Fixed-Bed Units for Chemical-Looping Combustion. Chemical Engineering Journal 2013 04/04/2014 13/37 IASE Seminar Series