Recent developments on quality assurance of fuel cell hydrogen

Transcription

1 Recent developments on quality assurance of fuel cell hydrogen Arul Murugan, Thomas Bacquart, Paul Brewer Gas Metrology Group NPL Cutting Edge Research for Gas Metrology, CCQM-GAWG (13 Oct 2016) Project meeting 14 th January 2015 NPL Management Ltd - Internal

2 Overview of presentation A Growing Hydrogen Economy Four Metrology Challenges for the Hydrogen Industry NPL s Hydrogen Impurity Enrichment Device NPL Management Ltd - Internal

3 A Growing Hydrogen Economy

4 Hydrogen vehicles Hyundai ix35 Toyota Mirai Honda Clarity Exhaust Emissions (CO 2, NOx, SO 2, particulates) Range Top speed Fuel cell Vehicles Only water Zero 500 km 160 km/hr UK H2 Mobility report (2013) Riversimple

5 Hydrogen refuelling stations Supplied at 700 bar (or 350 bar) 5 kg per fill (full tank) 3 minutes to fill ~ 50 for full tank Hydrogen produced by electrolysis or steam methane reforming

6 UK s hydrogen economy 2030 A report by UK H2Mobility (2013) 1.6 million fuel cell vehicles on the road in the UK 1,100 hydrogen refuelling stations in operation 254,000 tonnes of hydrogen produced a year

7 Four Metrology Challenges for the Hydrogen Industry

8 Challenge 1 Flow Metering Refuelling stations cannot cost their customers with required accuracies Flow meters in the refuelling station must be accurate to 1% (OIML R 139-1) Hydrogen supplied can vary up to 700 bar in pressure and between -40 to 85 o C during refuelling Unknown mass of hydrogen is lost during venting

9 Challenge 2 Quality Assurance Usually platinum can degrade in the presence of impurities (such as hydrogen sulphide or carbon monoxide) Reactive gases Water Oxygen Carbon dioxide Total hydrocarbon compounds Formic acid Carbon monoxide Ammonia Total halogenated compounds Formaldehyde Total sulphur compounds (5 µmol/mol) (5 µmol/mol) (2 µmol/mol) (2 µmol/mol) (0.2 µmol/mol) (0.1 µmol/mol) (0.1 µmol/mol) (0.05 µmol/mol) (0.01 µmol/mol) (0.004 µmol/mol) Inert gases DIRECTIVE 2014/94/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 22 October 2014 on the deployment of alternative fuels infrastructure: The hydrogen purity dispensed by hydrogen refuelling points shall comply with the technical specifications included in the ISO standard. Helium Nitrogen Argon Non-gases Particulates (300 µmol/mol) (100 µmol/mol) (100 µmol/mol) (1 mg/kg)

10 Challenge 3 - Quality Control ISO recommends adding quality control measures in order to: Continuously monitor key impurities (rather that waiting for annual purity checks) Monitor levels of reactive species that could degrade the fuel cell Switch off pump as soon as any impurities are detected Quantum cascade analyser by Cascade Technologies ProCeas by AP2E Online analysers are available but have not been tested for hydrogen quality control

11 Challenge 4 - Sampling Hydrogen sample Hydrogen refuelling station Hydrogen purity laboratory There are no official guidelines for sampling hydrogen and therefore stations may be using: Inaccurate technique for sampling (contamination issues) Inappropriate sampling device (e.g. stainless steel opposed to sulfinert) Wrong sampling vessels/cylinders

12 EMPIR Metrology for Hydrogen Vehicles Supported by 43 stakeholders including: Flow metering Quality assurance 20 project partners: Quality control Sampling Creating impact

13 NPL s Hydrogen Impurity Enrichment Device

14 Problems for commercial laboratories Number of instruments Capital expenditure Small volumes of sample 7 ~ 500k total Cannot use low pressure in small vessels A commercial hydrogen purity laboratory Limits of detection Time for analysis Not feasible with routine instruments such as GC-MS Too long (several instruments)

15 Hydrogen impurity enrichment Vessel containing high pressure hydrogen sample Palladium based hydrogen membrane Empty (turbo vacuumed) vessel CO H 2 H 2 H2 CO Allows measurement of lower amount fractions Better signal-to-noise Can be used with any analyser

16 Problems for commercial laboratories Number of instruments Capital expenditure Small volumes of sample 7 ~ 500k total Cannot use low pressure in small vessels A commercial hydrogen purity laboratory Limits of detection Time for analysis Not feasible with routine instruments such as GC-MS Too long (several instruments)

17 Problems for commercial laboratories Number of instruments Capital expenditure Small volumes of sample 2-3 ~ 500k total Cannot use low pressure in small vessels A commercial hydrogen purity laboratory Limits of detection Time for analysis Not feasible with routine instruments such as GC-MS Too long (several instruments)

18 Problems for commercial laboratories Number of instruments Capital expenditure Small volumes of sample 2-3 < 200k total (using routine GC-MS) Cannot use low pressure in small vessels A commercial hydrogen purity laboratory Limits of detection Time for analysis Not feasible with routine instruments such as GC-MS Too long (several instruments)

19 Problems for commercial laboratories Number of instruments Capital expenditure Small volumes of sample 2-3 < 200k total (using routine GC-MS) No problems with low volume samples A commercial hydrogen purity laboratory Limits of detection Time for analysis Not feasible with routine instruments such as GC-MS Too long (several instruments)

20 Problems for commercial laboratories Number of instruments Capital expenditure Small volumes of sample 2-3 < 200k total (using routine GC-MS) No problems with low volume samples A commercial hydrogen purity laboratory Limits of detection Time for analysis GC-MS can be used for most impurities Too long (several instruments)

21 Problems for commercial laboratories Number of instruments Capital expenditure Small volumes of sample 2-3 < 200k total (using routine GC-MS) No problems with low volume samples A commercial hydrogen purity laboratory Limits of detection Time for analysis GC-MS can be used for most impurities Less time needed to use all instruments

22 Hydrogen Impurity Enrichment Device (HIED) NPL s tracer enrichment method Impurity Hydrogen Hydrogen sample Combine Measure krypton Enrichment factor Krypton (Tracer) Krypton Hydrogen removal Enrichment factor Measure impurities Measure krypton

23 Calculating enrichment factors Hydrogen Impurity Two methods can be used: Impurity Hydrogen CCCCCC = yy 2,II yy 1,II = PP 1,aa VV 1 ZZ 1,aa RRTT 1,aa + PP 2,aaVV 2 ZZ 2,aa RRTT 2,aa ( PP 1,bbVV 1 ZZ 1,bb RRTT 1,bb ) ( PP 2,bbVV 2 ZZ 2,bb RRTT 2,bb ) Krypton CCCCCC = yy 2,II yy 1,II = 1 yy 1,KKKK AA KKKK (eeeeeeeeeeeeeee) AA KKKK (ssssssssssssssss) yy KKKK (ssssssssssssssss) Rel. u/c = ~10% (k=2) Rel. u/c = ~2.5% (k=2) Ideal gas law method Krypton tracer method

24 Results Test 1 CO is lower CH 4 is slightly higher Reaction taking place? CH 4 = 2.008? ppm CO =? ppm N 2 = 2.023? ppm balance Enrichment x 60 CH 4 = ppm CO = ppm N 2 = ppm balance (+1.0%) (-10.5%) (+4.9%) CH 4 = ppm CO = ppm N 2 = ppm balance (+3.1%) (-7.8%) (+8.2%) Ideal gas law method Krypton tracer method

25 Results Test 2 CH 4 CO CH 4 CO CH 4 = 2.008? ppm CO =? ppm N 2 = 2.023? ppm balance Enrichment x 60 CH 4 = 0.106ppm CO = ppm N 2 = ppm balance (-94.7%) (-96.0%) (-93.4%) CH 4 = ppm CO = ppm N 2 = ppm balance (+3.1%) (-23.1%) (+28.4%) Ideal gas law method Krypton tracer method

26 Results Test 3 Air leak CH 4 = 1.506? ppm CO =? ppm N 2 = 1.537? ppm balance Enrichment x 60 CH 4 = ppm CO = ppm N 2 = ppm balance (-35.5%) (-33.3%) (+2.5%) CH 4 = ppm CO = ppm N 2 = ppm balance (+1.6%) (+10.0%) (+69.1%) Ideal gas law method Krypton tracer method

27 Conclusions Use krypton tracer method to calculate enrichment factor AND Use ideal gas law method to check for membrane failure or air leak

28 Further reading Advancing the analysis of impurities in hydrogen by use of a novel tracer enrichment method A. Murugan & A. S. Brown (2014) HOT ARTICLE

29 Next steps Currently using Pd-Ag coated with Pd-Cu 4 year Industrial Case PhD between NPL and Imperial College London to: - Develop improved membranes - Other types rather than palladium (possibly graphene) - Investigate optimal enrichment conditions (to prevent reactions) Marc Plunkett (PhD student) Prof. Kang Li (Academic) Dr. Arul Murugan (Industrial)

30 Thank You! Dr Arul Murugan (+44) The National Physical Laboratory is operated by NPL Management Ltd, a whollyowned company of the Department for Business, Innovation and Skills (BIS).

31 NPL s Hydrogen Purity Laboratory

32 Aims of the laboratory Provision of stable primary reference gas mixtures for laboratories and gas producers To provide validation of online hydrogen purity analysers for quality control To provide direct hydrogen purity analysis for hydrogen refuelling stations

33 NPL s capabilities Gas chromatography with mass spectrometer detector Ammonia cavity ringdown spectroscopy Water Quartz crystal microbalance Gas chromatography with thermal conductivity detector Helium Hydrocarbons Thermo-desorption - Gas chromatography with mass spectrometer detector Formaldehyde Organo-halogenated compounds Formic acid Oxygen Carbon dioxide Methane Carbon monoxide Sulphur Compounds Gas chromatography with methaniser and flame ionisation detector Argon Nitrogen FTIR Gas chromatography with helium discharge ionisation detector Gas chromatography with sulphur chemiluminescence detector

34 Missing capabilities Our limits of detection are not low enough to reach these specifications 1) Use alternative spectroscopic methods (even though more sample is needed per analysis ) 2) Develop a method for concentrating impurities in hydrogen Reactive gases Water Oxygen Carbon dioxide Total hydrocarbon compounds Formic acid Carbon monoxide Ammonia Total halogenated compounds Formaldehyde Total sulphur compounds (5 µmol/mol) (5 µmol/mol) (2 µmol/mol) (2 µmol/mol) (0.2 µmol/mol) (0.1 µmol/mol) (0.1 µmol/mol) (0.05 µmol/mol) (0.01 µmol/mol) (0.004 µmol/mol) Inert gases Particulates in hydrogen methods have not been developed yet We will develop this method next year Helium Nitrogen Argon Non-gases Particulates (300 µmol/mol) (100 µmol/mol) (100 µmol/mol) (1 mg/kg)