Energy storage in metal fuels energy and chemistry cycles

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1 Lehrstuhl für Energieanlagen und Energieprozesstechnik Prof. Dr.-Ing. V. Scherer Energy storage in metal fuels energy and chemistry cycles Lehrstuhl für Energieanlagen und Energieprozesstechnik Martin Schiemann Metalot Eindhoven 23. May 2018

2 coal biomass Helmstedterrevier.de Recycling MeClx to MeO/HCl metals Metalot Eindhoven 23. May 2018 Martin Schiemann 2

3 Climate Change Transition to renewables Picture-Alliance Metalot Eindhoven 23. May 2018 Martin Schiemann 3

4 Local and temporal availability We can power the world with wind, water and solar energy Using only around 1% of the land mass How do we move that energy to where we need it? How do we make it available when it is needed? Metalot Eindhoven 23. May 2018 Martin Schiemann 4

5 Energy Carriers Carrier Renewable Energy Source Energy Carrier Processing Spent Carrier Carbon- Free Energy Generation Energy carriers are needed to allow for international energy trade Renewable energy commodities and strategic energy reserves Energy carriers must not involve emission of carbon dioxide No carbon emissions at point of use or during recycling Metalot Eindhoven 23. May 2018 Martin Schiemann 5

6 Non-carbonaceous fuels Low volumetric energy density Low mass energy density of total storage system (50kg of hydrides for 1kg of hydrogen) Hydrogen is very explosive for wide range of fuel-air concentrations Metalot Eindhoven 23. May 2018 Martin Schiemann 6

7 Non-carbonaceous fuels Why not harvest this energy directly? Metals react exothermic with Oxygen Water Carbon dioxide Nitrogen Battery: low density, specific energy, carries oxidizer around Metal volumetric energy densities even surpass conventional fossil fuels Metalot Eindhoven 23. May 2018 Martin Schiemann 7

8 Reaction enthalpies 2Mg + O 2 2MgO kj/mol Mg 4 Al + 3 O 2 2 Al 2 O kj/mol Al 2 Zn + O 2 2 ZnO kj/mol Zn 4Fe + 3O 2 2Fe 2 O kj/mol Fe C + O 2 CO kj/mol C wikipedia Oxidation: Enthalpy comparable to carbon oxidation or above! Oxides used for Refractory Pigments Water treatment Rauschert Al 2 O 3 ceramics Alibaba.com Linkedin.com Metalot Eindhoven 23. May 2018 Martin Schiemann 8

9 Reaction enthalpies Mg + 2 CO 2 MgCO 3 + CO kj/mol Mg 2 Al + 3 CO 2 Al 2 O CO kj/mol Al 2 Na + 2 CO 2 Na 2 CO 3 + CO kj/mol Na 2 Li + 2 CO 2 Li 2 CO 3 + CO kj/mol Li Combustion in CO 2 : High enthalpy CO as by-product Path to carbon chemistry C + O 2 CO kj/mol C Process temperature may be limited by chemical equilibrium Take care: Carbonates tend to decompose MgCO 3 : ~350 C MgO, CO 2 CaCO 3 : ~850 C CaO, CO 2 Na 2 CO 3 : ~1600 C Na 2 O, CO 2, Na 2 O 2, CO Li 2 CO 3 : ~1400 C Li 2 O, CO 2 Metalot Eindhoven 23. May 2018 Martin Schiemann 9

10 Technical concepts Typical for fast conversion: Small particles Coal (40% of electricity ww) d p 100µm oil d d 30µm Milling Iron/aluminum Preparation of particles: Spraying Sodium/magnesium/ Razavi-Tousi et al., PowTech 284, 2015, Siemens CT, Erlangen, Germany Metalot Eindhoven 23. May 2018 Martin Schiemann 10

11 Combustion modes A: T boil,metal <T ad Metal evaporates Oxide condenses aerosols B: T boil,oxide <T ad <T boil,metal Oxides evaporate aerosols C: T ad <T boil,oxide,t boil,metal Solid particle formed Metalot Eindhoven 23. May 2018 Martin Schiemann 11

12 Metal flames Bergthorson et al. AppEn 2015, 160, Metal-bunsen-flames metal-air and metal-methane-air demonstrated Lithium spray flame Siemens CT, Erlangen, Germany Lithium burning in preheated CO 2 Metalot Eindhoven 23. May 2018 Martin Schiemann 12

13 Example: Iron combustion in air Iron: One of the most abundant metals Oxides not toxic Renewable reduction: Hydrogen from renewables Electrolysis 4Fe + 3O 2 2Fe 2 O kj/mol Fe Fe 2 O 3 decomposition: 1280 K Fe 3 O 4 solid 1863 K liquid decomposition: 2360 K FeO solid 1644 K liquid decomp.: 3000 K Metalot Eindhoven 23. May 2018 Martin Schiemann 13

14 Example: Iron combustion in air Pyrometry: T~ 2000 K Far below all boiling temperatures Aerosols observed Recent work: Panahi et al., Proc. Comb. Inst., submitted Metalot Eindhoven 23. May 2018 Martin Schiemann 14

15 Example: Lithium combustion in CO2 Metalot Eindhoven 23. May 2018 Martin Schiemann 15

16 Example: Lithium combustion in CO2 Experimental Setup water cooling isolation hot gas porous ceramic particle streak quartz glass tube pyrometer injector tube Ø 65 mm particle sampling probe Ø 30 mm inlet of Ar and Li particles hot gas gas heater CO 2 mass flow controller Schiemann et al., AppEn 2016, 162, N 2 Boundaries d p < 250 µm gas temperature: K gas/particle velocity: 1,1 1,5 m/s separated particles Two-color pyrometry image intensified CCD cameras measurement T p, d p for each particle T p and d p are measures for the reaction rate Sampling probe quenching of the reacting particles particle separation from the gas flow analysis of the burnout: X-ray diffraction CHN analyzer Metalot Eindhoven 23. May 2018 Martin Schiemann 16 SEM

17 Δt= 0.5 ms Example: Lithium combustion in CO2 Gas phase Pyrometry / Image analysis: 1. Gas phase combustion Very bright, high temperature Aerosol formation 2. surface reaction Dominating in time and mass conversion T p ~ 1620 K Surface Metalot Eindhoven 23. May 2018 Martin Schiemann 17

18 particle temperature [K] Example: Lithium combustion in CO2 Stages of the numerical combustion model in 100% CO distance to inlet [mm] Measurement: Solid samples Two reaction products: Li 2 O and Li 2 CO 3 Compare simulation of the reactor with measurement: good agreement Use model for larger devices 1 Inert heating 2 Lithium melting 3 Ignition and gasphase combustion 4 Surface combustion 5 Phase transitions Metalot Eindhoven 23. May 2018 Martin Schiemann 18

19 Example: Lithium combustion in CO2 Scale up 100 MW th Lithium Combustion Slag Tap Furnace - Design 1/8 Simulation Model Full energetic utilization Complete compustion to Li 2 CO 3 gas cleaning Lithium recycling efficiency >99% Li 2 CO 3 : liquid until decomposition (~1650 K) Avoid contamination of heat exchangers Similar problems known from coal combustion Solution: slag tap furnace steam generator slag tap furnace Metalot Eindhoven 23. May 2018 Martin Schiemann 19

20 7 m Example: Lithium combustion in CO2 Scale up 100 MW th Lithium Combustion Slag Tap Furnace 1/8 Simulation Model 12 m P. Maas, M. Schiemann, V. Scherer et al., Appl. Energy. (2017) accepted. Metalot Eindhoven 23. May 2018 Martin Schiemann 20

21 Example: Lithium combustion in CO2 Scale up 100 MW th Lithium Combustion Slag Tap Furnace 1/8 Simulation Model CO 2 input primary (174 t/h) P. Maas, M. Schiemann, V. Scherer et al., Appl. Energy. (2017) accepted. Metalot Eindhoven 23. May 2018 Martin Schiemann 21

22 Example: Lithium combustion in CO2 Scale up 100 MW th Lithium Combustion Slag Tap Furnace 1/8 Simulation Model CO 2 input primary (174 t/h) secondary (48 t/h) Li (10 t/h) gas outlet (to steam generator) gas P. Maas, M. Schiemann, V. Scherer et al., Appl. Energy. (2017) accepted. Metalot Eindhoven 23. May 2018 Martin Schiemann 22

23 Example: Lithium combustion in CO2 Scale up 100 MW th Lithium Combustion Slag Tap Furnace 1/8 Simulation Model CO 2 input primary (174 t/h) secondary (48 t/h) Li (10 t/h) gas outlet (to steam generator) gas P. Maas, M. Schiemann, V. Scherer et al., Appl. Energy. (2017) accepted. Metalot Eindhoven 23. May 2018 Martin Schiemann 23

24 Example: Lithium combustion in CO2 Scale up 100 MW th Lithium Combustion Slag Tap Furnace 1/8 Simulation Model CO 2 input primary (174 t/h) secondary (48 t/h) Li (10 t/h) gas outlet (to steam generator) gas slag catcher Li 2 CO 3 (43 t/h) P. Maas, M. Schiemann, V. Scherer et al., Appl. Energy. (2017) accepted. Metalot Eindhoven 23. May 2018 Martin Schiemann 24

25 Example: Lithium combustion in CO2 Scale up 100 MW th Lithium Combustion Slag Tap Furnace 1/8 Simulation Model CO 2 input primary (174 t/h) secondary (48 t/h) Li (10 t/h) gas outlet (to steam generator) P. Maas, M. Schiemann, V. Scherer et al., Appl. Energy. (2017) accepted. Metalot Eindhoven 23. May 2018 Martin Schiemann 25 gas slag catcher Li 2 CO 3 (43 t/h) outlet for Li 2 CO 3

26 Example: Lithium combustion in CO2 Scale up Tangential inflow causes swirl motion Particles collide with walls Almost complete particle capture possible High capture efficiency means high lithium recycling rate Conversion to Li 2 CO 3 complete Promising concept for lithium combustion in CO 2 Metalot Eindhoven 23. May 2018 Martin Schiemann 26

27 Summary and Outlook Metals identified as energy carriers Potential to act in thermal power production processes Chemistry processes based on metal fuels are possible Metals may replace/reduce input of carbonaceous feedstock First concepts presented for CO 2 utilization Hydrogen production Combustion (heat and oxides) Still a way to go Most studies are lab-scale Pilot-scale facilities needed Further attractive cases (economic/environmental) to be identified Metalot Eindhoven 23. May 2018 Martin Schiemann 27