BioGas and Fuel Cells BioGas 2020 Skandinavias Biogaskonferanse 2018, Fredrikstad, April Crina S. ILEA Contact:

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1 BioGas and Fuel Cells BioGas 2020 Skandinavias Biogaskonferanse 2018, Fredrikstad, April 2018 Crina S. ILEA Contact:

2 Christian Michelsen Institute (CMI) Founded in 1988 Two departments: Parts & Services Research & Development Prototype development from idea to product Space and energy Space & Energy

3 Types of fuel cell Fuel cells: energy conversion device that converts the chemical energy of a fuel gas directly to electrical energy and heat without the need for direct combustion as an intermediate step SOFC - Solid Oxide Fuel Cells MCFS - Molten carbonate fuel cell AFC - Alkaline Fuel Cells PAFC - Phosphoric Acid Fuel Cells PEMFC - Proton Exchange Membrane Fuel Cell

4 Low temperature and high temperature (HT)-PEM < 200oC SOFC: ca 800oC Hydrogen Compact Simple integration Fuel flexibillity (NG) High efficiency / low emissions Efficient CO2 separation possible Complex integration 4

5 SOFC How does it work? 50 m 5

6 Fuel Cell vs. Electrolysis

7 BioCellus (2007) 1 kw stack (40 cells) built and tested on H 2 and biogas from woods Maximum performance: 987 W Air and fuel utilization of 50 % 81 % of the heat removed by the heat pipes 7 hours continuous operation on woodgas Stable performance for the whole period Average performance: 300W Maximum performance: 700W (limited by fuel flow)

8 20 kw system - 24 stack SOFC hot box ( ) Co-production of electricity and hydrogen > 80 % efficiency CO 2 ready for storage 24 stack SOFC hot box

9 CHEOP-CC: SOFC on Natural Gas + CO 2 capture (2017) Air Air exhaust Hot air O2-SOFC NG + H2O Reformer + Pdmembranes Carbon rich Reformate Solid Oxide Fuel Cell Fuel/H2O/CO2 out Oxyfuel Afterburner H2O/CO2 exhaust H2 Heat Heat H2O Condenser DC/AC Electricity HT-PEM Air H2O CO2 Heat H2O Advantages of hybrid concept: 50% weight reduction due to integration of the PEM-system Highly efficient reformation of natural gas utilizing excess heat from the SOFC Including an oxygen pump before the afterburner, hence performing the combustion in pure oxygen, the exhaust only consists of steam and CO2 (captured)

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11 Pyrolysis - thermochemical decomposition of organic material at high temperatures into CO, H 2 and CO 2, with a controlled amount of O 2. - resulting gas mixture is called syngas Aim: - Develop and test a new reactor for fish sludge handling to obtain bio-syngas and solid residue (char) - Integrate and optimize the reactor and other components into a light and compact container for handling the fish sludge

12 Pyrolysis Fuel Cells

13 Green Fish Farm 13

14 If the Norwegian fish farming industry will manage to collect and re-use all the sludge from 1 million tones salmon/year to produce biogas then million m 3 CH 4 could be produced, equivalent to 0.7-2TWh energy(corr. revenue 236MNOK and 684MNOK - Natural gas price~0.038 euro/kwh). Currently the sludge is to a great extent deposited at the sea floor, but with the recent findings in e.g. Masfjorden and the expected growth in the industry, it is expected that within 10 years most of the sludge will have to be captured and recycled.

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17 H2020-LC-SC (Building a low-carbon, climate resilient future: secure, clean and efficient energy) combines renewable energy sources e.g. small wind mills, solar cells, innovative biogas reactors and fuel cells with battery and gas storages to an economically and ecologically optimized energy system. Concept includes: BioGas, Solar cells, Fish Farms, Electrical Ferry, microgrid, wind turbines, electrolyser, Bio-fuel - fuel cells, sea cables.

18 High efficient conversion of biogas from waste to electricity and heat using solid oxide fuel cells

19 BioGas Biogas - produced by the anaerobic digestion of organic matter e.g plants, manure, sewage sludge, and organic wastes from industry and households. The raw biogas mainly consists of CH4 and CO2. Biogas contains various impurities at concentration levels that usually need to be lowered to increase durability of the utilization processes like engines, fuel cells, micro-turbines etc. Contaminant concentrations depend on the feedstock, process conditions and process controlling parameters.

20 Fuel Cell degradation Ni-YSZ anode measured in fuels containing H2S and thiophene at 0.25 A/cm 2 at 750 C. Even small amounts of H 2 S strongly affect the dry reforming reaction rate A drop in performance, cell fed with a CH 4 /CO 2 ratio of 1 due to deactivation of the dry reforming reaction. Iirreversible performance degradation with this impurity even at the lowest possible levels. Si condenses and deposits everywhere on the interconnect and the anode support down to the electrolyte interface at the three-phase boundary responsible for the loss in electrochemical performance

21 not a lot of public data available about variability of biogas compositions. In most of the biogas sources, there are usually daily, seasonal and long-term (>1 year) variations of composition depending on the feedstock and environmental conditions. Daily variations are typically related to daily feedstock input rate and schedule. Long-term variations are mostly related to feedstock type and in landfills related to the age of the landfill

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23 Conclusions More focus on biogas production Biogas or Syngas can be used a fuels in fuel cells Cleaning of the biogas is very important (e.g. siloxanes and H2S) Stable biogas composition is desired Salted fish sludge has the potential of generating large amounts of syngas need for new technologies

24 Thank you for your attention 24