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National Seminar ‘Creating Infrastructure for adoption of fuel cell Technology in India April 15, 2004

Recent Trends in Production of Hydrogen from Biomass. National Seminar ‘Creating Infrastructure for adoption of fuel cell Technology in India April 15, 2004. Dr. A. K. Gupta INDIAN INSTITUTE OF PETROLEUM DEHRADUN, INDIA. Why Biomass to hydrogen?

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National Seminar ‘Creating Infrastructure for adoption of fuel cell Technology in India April 15, 2004

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  1. Recent Trends in Production of Hydrogen from Biomass National Seminar‘Creating Infrastructure for adoption of fuel cell Technology in IndiaApril 15, 2004 Dr. A. K. GuptaINDIAN INSTITUTE OF PETROLEUMDEHRADUN, INDIA

  2. Why Biomass to hydrogen? • Biomass has the potential to accelerate the realization of hydrogen as a major fuel of the future. • Biomass is renewable, consumes atmospheric CO2 during growth and is a CO2 neutral resource in life cycle. • It can have a small net CO2 impact compared to fossil fuels.

  3. Routes to H2 From Biomass Biomass conversion technologies can be divided into two categories. Direct production routes (simplicity of process). Conversion of storable intermediates (additional production steps, distributed production of intermediates, lower transportation costs of biomass, larger-scale H2 production facilities.) Both categories involve thermochemical and biological routes.

  4. Pathways From Biomass to H2 Biomass Thermochemical Gasification Pyrolysis High Pressure Aqueous Severe H2/CO CH4/CO2 CH4/CO2 CH1.4O.6 Synthesis Bio-shift CH3OH/CO2 Reforming shift Reforming shift Shift Reforming shift H2/CO2 H2/CO2 H2/CO2 H2/CO2 H2/CO2 H2/C

  5. Pathways from Biomass to H2 Biomass Biological Anaerobic Digestion Fermentation Metabolic Processing CH3CH2OH/CO2 CH4/CO2 Bio-shift Reforming shift Reforming shift Photo- biology Pyrolysis H2/CO2 H2/CO2 H2/CO2 H2/C H2/O2

  6. Metabolic Processing of Biomass H2 from biomass can also be produced by metabolic processing to split water via photosynthesis or to perform the shift reaction by photo biological organisms. The use of microorganisms to perform the shift reaction is of great relevance to hydrogen production because of the potential to produce CO in the product gas far below than in water gas shift catalysts.

  7. Direct Production of H2 From Biomass Gasification coupled with water-gas shift is the most widely practiced process route for biomass to H2. Thermal, steam and partial oxidation gasification technologies are under development around the world. Feedstocks include both dedicated crops and agricultural and forest product residues of hardwood, softwood and herbaceous species.

  8. Oxidative Pyrolysis By including O2 in the reaction separate supply of energy is not required Biomass + O2 CO + H2 + CO2 + Energy If air is used to supply O2 then N2 is also present. Examples : GTI high pressure O2 blown gasifier, CFBD (TPS Termiska), High pressure slurry bed entrained flow gasifier (Texaco)

  9. Direct Solar Gasification • Several investigators have examined the use of solar process heat for gasification or organic solid wastes to produce H2. • Studies have shown favourable economic projections for solar gasification of carbonaceous materials such as agricultural waste to produce syn gas for producing H2.

  10. Other Direct Processes Explored….. • Several other heat sources and chemistries have been explored for H2 from biomass/organic materials. • Use of thermo-nuclear device to vaporize waste organic materials in an underground large-scale plasma process. • Electrochemical oxidation of solid carbonaceous wastes.

  11. Biomass Derived Synthesis Gas (Syn Gas) Conversion • Sponge Iron and related processes • Steam Iron processes is one of the oldest processes for producing H2 from syngas. (developed as early as 1910). • Fe3O4 + 4CO 3Fe + 4CO2 • 3Fe + 4H2O Fe3O4 + 4H2 • Recently sponge Iron process has been extended to FeO • 3FeO + H2O H2 + Fe3O4 • Metal hydrides (e.g. LaNi5, and La Ni4.7 Al0.3) has also been investigated for continuous hydrogen recovery from biomass gasification mixtures lean mixtures.

  12. Supercritical Conversion of Biomass • Aqueous conversion of whole biomass to H2 under low temperature supercritical conditions in another area of investigation in recent years. • Corrosion, pumping of biomass slurry, improvement in heating rates, heat transfer, commercial reactor system development are some of the problems need attention.

  13. Pyrolysis to Hydrogen and Carbon or Methanol • This is a high temperature two-step process involving • Conversion of biomass to methane • Thermal decomposition of methane to H2 and clean carbon-black • Typical overall stoichiometry is: • CH1.44 O0.66 C + 0.6 H2 + 0.66 H2O • The process is called Hydrocarb process • In another process “Carnol Process” methanol is produced with H2 • CH1.44 O0.66 + 0.30 CH4 0.64 C + 0.66 CH3OH

  14. Storable Intermediates • Bio-oil reforming • Pyrolysis of biomass produces liquid product called bio-oil or pyrolysis oils which is the basis of several processes for producing H2 via catalytic steam reforming of bio-oil at 750-850°C. • Bio-oil + H2O CO2 + H2 • CO + H2O CO2 + H2 • Pyrolysis is endothermic: • Biomass + Energy  Bio-oil +Char + Gas • Over all stoichiometry gives a maximum yield of 17.2 gH/100 g bio-oil i.e. about 11.2% based on wood. • Typical over all stoichiometry based on wood is: • CH1.9 O0.7 + 1.26 H2O CO2 + 2.21 H2

  15. Storalable Intermediates • Regional networks of pyrolysis plants can be established to provide bio-oil to a central steam reforming facility • Methanol/Ethanol can also be produced from biomass by a variety of technologies and used for on-board reforming for transportation • Methane could be produced by anaerobic digestion which on steam reforming produce H2 • Methane could be pyrolysed to H2 and carbon, if markets for carbon black are available.

  16. Co-production of Methanol and Hydrogen • Both methanol and H2 are well suited for fuel cell vehicles (FCV’s) • Methanol and H2 can be produced from biomass via gasification • Overall efficiencies of around 55% for methanol and around 60% for hydrogen may be obtained. • Using liquid phase methanol synthesis and ceramic membranes for gas separation are crucial to lowering the cost of production. • All larger scales, conversion and power systems (especially the combined cycle) may have higher efficiencies. • R&D is necessary to verify and improve the performance.

  17. Biomass Pretreatment, drying, chipping Gasifier Reformer for higher hydrocarbons Gas Cleaning Shift to adjust CO/H2 ratio Methanol Production H2 Production Hydrogen ) Purge gas Electricity Gas Turbine/boiler Steam Turbine Electricity KEY PROCESS STEPS IN BIOMASS TO METHANOL AND H2 Methanol

  18. ExampleHynol Process: This process produces H2 and methanol from biomass with reduced CO2 emissions. Steps involved: • Hydrogasification of biomass • Steam reforming • Methanol synthesis from Syn gas produced.

  19. Areas of Research and Development Feed stock preparation : For thermochemical routes, variety and nature of feeds for high temperature and pressure reactors. For biological routes, pretreatment to increase accessibility. Gasification gas conditioning : Key to utilization of H2 in fuel cells. In Gasificationpresence of Hydrocarbons, N2, sulfur, chlorine compounds must be addressed not only for end use applications shift gas reaction catalyst and separation systems such as PSA. System integration : Integration of several steps, Techno-economics of process alternatives to match the optimum technology with the available feedstocks.

  20. Modular systems approach : There is an opportunity for biomass systems to address small scale and remote applications. These systems will require novel conversion and gas conditioning technologies, designed for the resources available in a particular region. Value Co-product integration : Appropriate systems for conversion of by-product streams from chemical and biological conversion of biomass, are the best prospect for near-term development. Larger-scale demonstration : Most promising technologies will need to be selected at larger scale with successful utilization of H2 (i.e. fuel cells, IC engines, turbine etc.) There are other challenges of storage and utilization technologies.

  21. ISSUES Since H2 content in Biomass is low the yield of H2 is low (Approx. 6% vs. 25% of CH4) Energy content of biomass is also low due to 40% O2 content. Low energy content of biomass is inherent limitation of the process since over half of H2 from biomass comes from splitting of water in steam reforming. continued

  22. …ISSUES Even at reasonable high efficiency, production of H2 from biomass is not presently economically competitive with natural gas steam reforming without the advantage of high-value co-products, very low cost biomass and potential environmental incentives. There are no completed technology demonstrations.

  23. THANK YOU

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