Self-Sustaining Slow Pyrolysis Process

Transcription

1 Self-Sustaining Slow Pyrolysis Process Biomass-derived charcoal for metal production M. Cooksey, A. Deev, N. Haque, J. Donnelly, A. Brent and A. Guiraud 1 st Australia-Japan Symposium on Carbon Resource Utilisation November 2016 Melbourne, Australia MINERAL RESOURCES

2 Questions about the use of biomass/charcoal for low CO 2 emissions metal production Why is CSIRO investigating the use of charcoal for metal production? Can charcoal be considered to be a sustainable fuel with near zero net CO 2 emissions? Are there sufficient biomass resources already available in Australia to supply enough carbon for metal production? Can charcoal be produced at a cost comparable with coal/coke now? Is there a large-scale charcoal production process, capable of producing high quality charcoal from waste biomass at low cost and high efficiency? 2 Biomass-derived charcoal for metal production Adrien Guiraud

3 Why is CSIRO investigating the use of charcoal for metal production? Can charcoal be considered to be a sustainable fuel with near zero net CO 2 emissions? Are there sufficient biomass resources already available in Australia to supply enough carbon for metal production? Can charcoal be produced at a cost comparable with coal/coke now? Is there a large-scale charcoal production process, capable of producing high quality charcoal from waste biomass at low cost and high efficiency? 3 Biomass-derived charcoal for metal production Adrien Guiraud

4 Carbon Use in Metal Production Silicon Aluminium Iron & Steel ~850 kg C / t Si (SiO 2 + 2C Si + 2CO) ~355 kg C / t Al (2Al 2 O 3 + 3C 4Al + 3CO 2 ) kg C / t steel (2Fe 2 O 3 + 3C 4Fe + 3CO 2 ) 4 Biomass-derived charcoal for metal production Adrien Guiraud

5 Carbon Use in Metal Production 1,000.0 Annual Carbon Consumption (Mt) Silicon Aluminium Steel Australia Global 5 Biomass-derived charcoal for metal production Adrien Guiraud

6 GHG Emissions from Metal Production Annual GHG emissions (Mt CO 2 e) 10, , Silicon Aluminium Steel Australia Global > 3 billion tonnes of CO 2 e per year Metal production account for ~7% of global GHG emission annually Reductive smelting of iron ore and alumina represent ~90% of GHG emission from minerals/metals industry 6 Biomass-derived charcoal for metal production Adrien Guiraud

7 Why is CSIRO investigating the use of charcoal for metal production? Can charcoal be considered to be a sustainable fuel with near zero net CO 2 emissions? Are there sufficient biomass resources already available in Australia to supply enough carbon for metal production? Can charcoal be produced at a cost comparable with coal/coke now? Is there a large-scale charcoal production process, capable of producing high quality charcoal from waste biomass at low cost and high efficiency? 7 Biomass-derived charcoal for metal production Adrien Guiraud

8 Use of biomass for low CO 2 emissions metal production 8 Biomass-derived charcoal for metal production Adrien Guiraud

9 Why is CSIRO investigating the use of charcoal for metal production? Can charcoal be considered to be a sustainable fuel with near zero net CO 2 emissions? Are there sufficient biomass resources already available in Australia to supply enough carbon for metal production? Can charcoal be produced at a cost comparable with coal/coke now? Is there a large-scale charcoal production process, capable of producing high quality charcoal from waste biomass at low cost and high efficiency? 9 Biomass-derived charcoal for metal production Adrien Guiraud

10 Potential Charcoal use for BF-BOF Steelmaking Cokemaking blend component BF lump charcoal charge BF nut coke replacement BF carbon/ore composites BF pre-reduced feed Sintering solid fuel BF tuyere fuel injectant Min Max 0% 20% 40% 60% 80% 100% Direct Charcoal Substitution (%) Net Emissions Saved (t-co 2 e/t-crude steel) Notes: Percentages are based on 2.2 t-co 2 /t-crude steel Direct substitutions only (no efficiency changes). Source: J G Mathieson et al, Utilisation of Biomass as a Alternative Fuel in Ironmaking, Chapter 25 in Iron Ore: Mineralogy, Processing and Environmental Issues, Editor: Dr L Lu, Woodhead Publishing (in press). 10 Biomass-derived charcoal for metal production Adrien Guiraud

11 Charcoal for metal production in Australia Annual Carbon Consumption (Mt) Iron & Steel Aluminium Silicon Current Charcoal Use Potential Charcoal Use Non-Substitutable Carbon Use 11 Biomass-derived charcoal for metal production Adrien Guiraud

12 Supply of Biomass from Sustainable Sources Woody biomass Forest residues Wood processing Agriculture Wheat stubble Bagasse Horticulture Nut wastes Grape marc Woody weeds Camphor Laurel 12 Biomass-derived charcoal for metal production Adrien Guiraud

13 Supply of Biomass from Sustainable Sources Short-Medium Term (5-10 years) Annual Biomass Residues: 7.4 Mt (dry basis) Charcoal Production (30% yield) Mt charcoal / year 3.4 Wood processing In-forest Non-forestry Long term(10 15 years) Dedicated plantations of short rotation biomass species with a growth development time of around 7 8 years (e.g. mallee in WA) to ensure a secure supply of biomass material from sustainable sources. 13 Biomass-derived charcoal for metal production Adrien Guiraud

14 Why is CSIRO investigating the use of charcoal for metal production? Can charcoal be considered to be a sustainable fuel with near zero net CO 2 emissions? Are there sufficient biomass resources already available in Australia to supply enough carbon for metal production? Can charcoal be produced at a cost comparable with coal/coke now? Is there a large-scale charcoal production process, capable of producing high quality charcoal from waste biomass at low cost and high efficiency? 14 Biomass-derived charcoal for metal production Adrien Guiraud

15 Charcoal prices vs Coking Coal Charcoal Price (US$/t) USA - Import Indonesia - Export China - Import Paraguay - Export Coking Coal 15 Biomass-derived charcoal for metal production Adrien Guiraud

16 Techno-economics of Biomass to Charcoal Feasible/attractive option in Steelmaking when the value of the by-products and value-inuse of charcoal are realised with a carbon price high enough Potential to further reduce CAPEX and OPEX through a continuous energy efficient pyrolysis process Biomass cost includes collection, chipping and drying Transport cost covers a distance of 150 km to a biomass processing facility Capital cost is for a slow pyrolysis plant with high charcoal yield (30%), producing 100,000 tonnes of charcoal / year 16 Biomass-derived charcoal for metal production Adrien Guiraud

17 Why is CSIRO investigating the use of charcoal for metal production? Can charcoal be considered to be a sustainable fuel with near zero net CO 2 emissions? Are there sufficient biomass resources already available in Australia to supply enough carbon for metal production? Can charcoal be produced at a cost comparable with coal/coke now? Is there a large-scale charcoal production process, capable of producing high quality charcoal from waste biomass at low cost and high efficiency? 17 Biomass-derived charcoal for metal production Adrien Guiraud

18 Development of a Large Scale Pyrolysis Process 18 Biomass-derived charcoal for metal production Adrien Guiraud

19 CSIRO Autothermal Pyrolysis Technology Pilot-Scale Plant 1,000 t charcoal / year pilot-scale plant designed, constructed and commissioned at CSIRO s Laboratories in Melbourne (Australia) Operated since 2013 ADVANTAGES Innovative: patented design Highly energy efficient: no external high-grade heat required once at operating temperature (low-grade heat still needed for drying the feed material) Flexible: Can process small-sized feedstocks (wood wastes or forest residues) High Productivity: Continuous operation, high charcoal yield Full value recovery of by-products as pyrolysis gas and condensate are not diluted Low cost: Simple mechanical design (no moving parts in hot zone), ensuring minimum capital and maintenance costs. Scalable: No heat transfer limitation due to scaling up the reactor to large sizes, as no supply of external heat to the material is needed 19 Biomass-derived charcoal for metal production Adrien Guiraud

20 CSIRO Autothermal Pyrolysis Technology Process Flow Diagram 20 Biomass-derived charcoal for metal production Adrien Guiraud

21 CSIRO Autothermal Pyrolysis Technology Performance Autogenous mode of operation achieved for: batch process up to 4 hours continuous operation Maximum core temperature in the reactor during continuous operation: 520 C Charcoal properties: Moisture < 0.5% Fixed Carbon (dry basis) > 85 % Charcoal yield: 30% NEXT STEPS: Complete process characterisation on wood chips Upgrade pilot plant for extended (>24 h) continuous operation Evolution of reactor temperature during pilot plant operation 21 Biomass-derived charcoal for metal production Adrien Guiraud

22 Concluding Remarks Coal/coke substitution by biomass-derived charcoals can provide a low capital path to low CO 2 emissions for metal production Enough biomass residues are already available in Australia to supply primary metal production for the next 5-10 years Establishing a low-cost, large-scale pyrolysis technology is crucial to widespread implementation Current economics prevent widespread substitution of coking coal by charcoal in Australian steelmaking industry Silicon metal production is the most logical pathway to develop and commercialise as silicon producers already prefer to use charcoal to coal 22 Biomass-derived charcoal for metal production Adrien Guiraud

23 Acknowledgement Contribution by many CSIRO colleagues and particularly the SPE and IPC groups: Michael Somerville, Alex Deev, Nawshad Haque, Jason Donnelly, Dylan Marley, Rowan Davidson, Andrew Brent, Christian Doblin and Mark Cooksey This work has also been supported by OneSteel/Arrium and BlueScope Steel as part of the Australian CO2 Breakthrough Program between 2006 and Biomass-derived charcoal for metal production Adrien Guiraud

24 Thank You Adrien Guiraud Senior Process Engineer Sustainable Process Engineering e adrien.guiraud@csiro.au t MINERAL RESOURCES