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Experimental Investigation of the The Chemical Processes in High-Temperature, Pressurized Gasification of Black Liquor. Jim Frederick Chalmers. Objective of the Study. Obtain basic data on the chemical processes in black liquor gasification conditions of industrial entrained-flow gasifiers
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Experimental Investigation of theThe Chemical Processes inHigh-Temperature, Pressurized Gasification of Black Liquor Jim Frederick Chalmers
Objective of the Study • Obtain basic data on the chemical processes in black liquor gasification • conditions of industrial entrained-flow gasifiers • Develop sub-models of the gasification kinetics • Incorporate these sub-models into the detailed gasifier model under development at ETC • Validate the model with data from the ETC pilot gasifier
Gasifier Design Considerations:Carbon and Sulfate Conversion 100 mm particles P = 1 bar Devolatilization Gasification of fixed carbon Sulfate Reduction 0 0.5 1 1.5 2 Time, s
Gasifier Design: Effect of Pressure on Carbon Conversion Rate • “Gasification rate slows by a factor of 5 to 6 when pressure increases from 1 bar to 30 bar.” • Frederick, Whitty, Hupa; temperatures <800oC • “Pressure per se does not slow gasification” • Whitty; temperatures <800oC • “Pressure does slow the rate of gasification of black liquor char.” • Saviharju, Moilanen, and van Heiningen; temperatures <800oC
100 100 80 80 80 80 60 60 60 60 40 40 40 40 20 20 20 20 0 0 0 0 0.0 0.0 0.5 0.5 1.0 1.0 1.5 1.5 Gasifier Design: Tar Production(Sricharoenchaikul et al., 2002) Pyrolysis, 900oC, 1 bar Pyrolysis, 1000oC, 1 bar Tar Tar Gases Gases %C input in BLS %C input in BLS Fixed C Fixed C CO3= CO3= Residence time, s Residence time, s
100 Total TRS H2S 80 60 40 20 0 Gasifier Design: Sulfur Speciation(Iisa et al., 2001) 15% H20 Vapor H2S % of Sulfur Na2S 700 800 900 1000 1100 Temperature, °C
0.6 2% CO2 in N2 1000oC 0.5 0.4 1 MPa 0.5 MPa Carbon in char, % of C in BLS 0.3 0.2 0.1 Nohlgren et al., 2002 0.0 0 1 2 3 4 5 Time (s) Available Data on Impact of Pressure on Gasification at 950-1000oC
Particle Feeder Gasification Facilities Gas Preheat • Pressurized entrained-flow reactor (PEFR) • To 80 bar • To 1500oC • To 10 s residence time • Any gas mixture • Supporting analytical capabilities • On-line: gases, tar • Off-line: char, inorganics Reaction Zone Product Collector
Gasification Expertise IPST: Scott Sinquefield and Ingrid Nohlgren Chalmers: Jim Frederick, Kristiina Iisa, and Hans Theliander Georgia Tech: Pradeep Agrawal Consultants: Kevin Whitty, U. of Utah; Larry Baxter, BYU
Deliverables • A final report documenting experimental data on • carbon conversion • tar production • sulfate reduction • the fate of alkali metals and chloride • Sub-models developed from this data. • A report documenting the collaboration with the Swedish Black Liquor Gasification research project • Incorporation of the sub-models developed into the detailed computational (CFD) model • A comparison of modeling results with experimental data from the ETC pressurized pilot gasifier.