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AN OVER VIEW OF FUEL PROCESSOR TECHNOLOGIES FOR FUEL CELL APPLICATIONS. K.Venkateshwarlu, T.Krishnudu and K.B.S.Prasad Indian Institute of Chemical Technology Hyderabad- 500 007, India. Fuel Processing. Fuel Processor. C + O 2 CO 2 C + H 2 O CO + H 2 C + CO 2 2CO
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AN OVER VIEW OF FUEL PROCESSOR TECHNOLOGIES FOR FUEL CELL APPLICATIONS K.Venkateshwarlu, T.Krishnudu and K.B.S.Prasad Indian Institute of Chemical Technology Hyderabad- 500 007, India
C + O2 CO2 C + H2OCO + H2 C + CO2 2CO CO + H2O CO2 + H2 CO + 3H2 CH4 +H2O Gasification of solid fuels Generic Types Moving bed Fluidized bed Entrained bed Second generation BGL Shell Texaco KRW HT Winkler and many more
Steam Reforming CxHy + x H2O x CO + (x + y)/2 H2 CxHyO + (2x-1)H2O n CO2 + (2n-1+(m/2))H2 Catalytic system: CuO/ZnO, CuO/SiO2, CuO/ZnO/SiO2 For Methanol: 250-2600C Ethanol : >3000C Advantages : Maximum Hydrogen generation Disadvantages: Indirect Heat transfer
Partial Oxidation • CxHy + x/2 O2 x CO + y/2 H2 • Advantages: • Any type of hydrocarbon • Direct Heat transfer Disadvantages: • Low H2 production • Dilution of gas with N2 • Soot formation
Auto thermal Reforming • CH4 +H2O CO+3H2H=+206.16 kJ/mol • CH4+1/2O2 CO+2H2 H= -36 MJ/kmol • Combination of Steam Reforming and partial oxidation • Reactions are balanced in such a way net energy requirement is Zero (H = 0)
Catalytic decomposition • CH3OH 2 H2 + CO • Mostly suitable for Alcohols • Soot formation and carbon deposition for • Hydrocarbons
Desulphurisation • Gas phase Desulphurisation • ZnO + H2S ZnS (s) + H2O (g) • 2 to 3 kg ZnO sufficient for one year Automobile operation • Liquid Fuel Desulphurisation • Gasoline 30-40 ppm 1-2ppm Sulphur • For high sulphur Fuels hydro treatment followed by gas phase • Desulphurisation Adsorption Chemical reaction
High temperature & Low temperature Shift reaction CO + H2O CO2 + H2 HT Shift: Iron and Chromium Oxide Catalyst. Temperature 350-4500C LT Shift: Copper and Zinc Oxide Catalyst. Temperature 200-2500C
Carbon Monoxide Clean-up • Chemical • Preferential oxidation • CO + ½ O2 CO2 • H2 + ½ O2 H2O • Pt, Pd, Rh, Ru are catalysts (~ 1200C) • Methanation • CO + 3 H2 CH4 + H2O • Ru, Rh are catalysts. Temperature 100-2200C • Physical • Pressure Swing Adsorption (PSA) • Membranes-Metal or polymeric • Solvent Absorption
Fuel Processor using Membrane Reactor CO + H2O = CO2 + H2 - - - - - - - - - - - - - - - - - H2 Fuel Air H2O Primary Reformer H2, CO2, N2 H2,CO,N2 To Fuel Cell
Novel Reformer Technologies • Solvent enhanced reforming • Calcium Oxide along with steam reforming catalyst is added. • Composition 90% H2, 10% CH4, 0.5% CO2 and <50ppm CO • Downstream processing load is reduced. • Ion transport membrane reforming • Oxygen on one side of the membrane (1-5 psig) • Methane & steam on the other side of the membrane (100-500 psig) • Plasma Reformers • HT plasma (3000-100000C) is generated by electric arc in • plasmatron
10 kW Reformer at IICT • Methanol – Steam Reformer using indigenous catalyst developed • Reformer Integrated with a 500W PEM fuel Cell • Funding Agency: MNES (Rs. 60 lakhs)
Present Status of Work -Project : 50 kw fuel cell power pack for technology demonstration - Outlay : Rs. 234 lakhs. - Funding agency : MNES
Conclusions • Presently liquid fuels like gasoline & Diesel which contain high aromatic content and sulfur are not very suitable for on board applications. • Availability of Methanol & Ethanol for fuel uses are inadequate. • For use of natural gas economic and environmental benefits are to studied in detail. • A multi fuel Reformer needs to be developed (For fuels with small range of C/H ratio). • Thrust areas for R&D • Development of reactors/separators (Membrane) • Indigenous Catalyst development