H 2 Production from Biomass Feedstocks Utilising a Spout-Fluidised Bed Reactor

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1 75 th IEA-FBC Meeting Skive, Denmark 23 th -25 th October 2017 H 2 Production from Biomass Feedstocks Utilising a Spout-Fluidised Bed Reactor Peter Clough, Liya Zheng, Paul Fennell p.t.clough@cranfield.ac.uk, p.fennell@imperial.ac.uk

2 What are the uses of H 2?

3 How is H 2 produced? World H 2 production: ~55 Mt/yr (2015) Coal 18% Electrical 4% Oil 30% Natural Gas 48%

4 SMR process description

5 Better option SMR + CaL = SER

6 SER process description - Simplified

7 CH 1.6 O H 2 O + CaO 2H 2 + CaCO 3 SER process description

8 CH 1.6 O H 2 O + CaO 2H 2 + CaCO 3 SER process description

9 CH 1.6 O H 2 O + CaO 2H 2 + CaCO 3 SER process description

10 Reactor design Cooling jacket Biomass feeding system Steam generator Flare stack Reactor furnace HPLC pump Feeding U-bend Furnace control box

11 / cm Reactor Design and Construction

12 Biomass/Coal feeding system Rotary hopper feeder

13 Combined Particles CaO CO 2 sorbent Combined sorbent and catalyst particle Ni Reforming catalyst

14 a Volatile Matter Reformed Gas H 2 Enriched Gas Biomass Diffusion Catalyst Diffusion Sorbent Devolatilisation Reforming and Tar Cracking Carbonation b Volatile Matter Internal Diffusion H 2 Enriched Gas Biomass Devolatilisation Diffusion Catalyst & Sorbent Reforming, Tar Cracking & Carbonation

15 Sorbent and catalyst materials Low-engineered Highly-engineered Materials preparation method Wet granulation (mechanical mixing) Hydrolysis Wet impregnation Spray drying / freeze drying Co-precipitation Sol-gel Maximise Particle porosity Similarity of reaction kinetics for carbonation and reforming Sorbent carrying capacity Particle and individual component lifetime Particle strength Resistance to attrition Ability to reuse/recycle spent material Minimise Material sintering Pore blocking/product layer resistances Unintended inter-component interaction Expense, difficulty and time to manufacture The quantity of unreactive material

16 Unsupported material preparation method CaO Hydration Hydrogen and wet reduction mixing before use H 2 O Ca(OH) 2 + NiO CaO + NiO CaO + Ni Extrude paste into particles, NiO dry and calcine

17 Degradation study of a novel polymorphic sorbent under realistic post-combustion conditions Supported material preparation method TEOS/ SiO 2 CaO Hydration and wet mixing Hydrogen reduction before use Ca(OH) 2 CaO + H 2 O/H + H 4 SiO 4 + NiO + C 2 S + H 4 SiO 4 NiO CaO + C 2 S + Ni NiO Extrude paste into particles, dry and calcine

18 Calcium looping carrying capacity supported and unsupported combined particles Carbonation 650 C, 15 vol.% CO 2 N 2 balance, 5 minutes Calcination 950 C, 100 vol.% CO 2, 1 minute C 2 S supported combined particle (CaO and NiO, µm) CO 2 carrying capacity in moles of CO 2 absorbed per mole of CaO as a percentage.

19 SER reaction conditions Conditions: 650 C ± 8 C 1 atm Steam 20 vol.%, N 2 balance S:C = 1.2 CH 1.6 O H 2 O + CaO 2H 2 + CaCO 3 U/U mf 3 80 cm K Bed of sand, CaO and Ni (content and particle sizes varied) 0.9 g/min Oak biomass ( µm) NiO Ni 650 C for 30 minutes in 5 vol.% H 2 Combined particles - 14, 26, 36 and 47 wt.% NiO = 11, 21, 28 and 37 wt.% Ni Total amount of CO 2 that could be produced from 1 min of biomass feeding: ~0.04 moles CO g CaO

20 Typical experimental profile

21 SER with unsupported combined particles µm µm Steady state period H 2 vol.% greater with more Ni H 2 vol.% greater with smaller particles Inefficient gasification or diffusional issues Approaches thermodynamic equilibrium FactSage thermodynamic only Particles

22 SER with 26 wt.% NiO C 2 S supported combined particles CH 4 decreased significantly with the addition of Si-based support Gas purity / vol.% Gas yield / mmol/g biomass

23 SER with combined particles Unsupported and C 2 S supported 26 wt.% Ni produced 60 and 70 vol.% pure H 2, respectively 60 mmol H 2 / g biomass 120 g H2 / kg biomass Average closure of ± 15.4 % for C, H and O Unsupported particles Average closure of ± 10.7 % for C, H and O C 2 S supported particles Average CO 2 capture of 32.8 % for µm Unsupported particles Average CO 2 capture of 55.7 % for µm C 2 S supported particles

24 Operational issues Attrition of particles Coking on particles Coking within the reactor Time

25 Conclusions Combined NiO and CaO particles produced (some with C 2 S support) Tested SER within a fluidised bed reactor with solid biomass feeding Stoichiometric steam to carbon ratios H 2 purity and yield did approach equilibrium Si-based support dramatically affected CH 4 production Demonstrated ability to balance SER reactions with gasification Coking limited reactions and operation

26 75 th IEA-FBC Meeting Skive, Denmark 23 th -25 th October 2017 H 2 Production from Biomass Feedstocks Utilising a Spout-Fluidised Bed Reactor Peter Clough, Liya Zheng, Paul Fennell p.t.clough@cranfield.ac.uk, p.fennell@imperial.ac.uk