CPFDMODELINGOFCOMODELING OF CO ENHANCED...
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7 th International Freiberg/Inner Mongolia C f IGCC & XL T h l i Conference on IGCC & XtL T echnologies, Coal Conversion and Syngas CPFD CPFD MODELING OF CO MODELING OF CO ENHANCED ENHANCED CPFD CPFD MODELING OF CO MODELING OF CO 2 ENHANCED ENHANCED COAL GASIFICATION IN CIRCULATING COAL GASIFICATION IN CIRCULATING FLUIDIZED BED REACTOR FLUIDIZED BED REACTOR FLUIDIZED BED REACTOR FLUIDIZED BED REACTOR Joanna Bigda , PhD Józef Popowicz, MSc, Tomasz Chmielniak, PhD 7-11 June 2015, Huhhot, Inner Mongolia, China
Transcript of CPFDMODELINGOFCOMODELING OF CO ENHANCED...
7th International Freiberg/Inner Mongolia C f IGCC & X L T h l iConference on IGCC & XtL Technologies,
Coal Conversion and Syngas
CPFDCPFD MODELING OF COMODELING OF CO ENHANCEDENHANCEDCPFDCPFD MODELING OF COMODELING OF CO22 ENHANCED ENHANCED COAL GASIFICATION IN CIRCULATING COAL GASIFICATION IN CIRCULATING
FLUIDIZED BED REACTORFLUIDIZED BED REACTORFLUIDIZED BED REACTORFLUIDIZED BED REACTORJoanna�Bigda, PhD
Józef Popowicz, MSc, Tomasz�Chmielniak,�PhD
7-11 June 2015, Huhhot, Inner Mongolia, China
ContentsContentsContentsContents
• IntroductionIntroduction
• CPFD modeling of coal gasification• Computational geometry and model setup• Computational geometry and model setup • Operating and boundary conditions• CPFD governing equation and Chemical reactions
• Simulations results• Instantaneous/Time-average Solids Volume FractionInstantaneous/Time average Solids Volume Fraction• Instantaneous Gas Species Mass Fraction• Validation of results
• Conclusions
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IntroductionIntroductionIntroductionIntroduction• The work was carried out within the frame of strategic project "Development of
coal gasification technology for high-efficiency production of fuels and energy"g gy g y gy
• Using of CO2 during pressurized gasification in circulating fluidized bed Attractive method of CO2 management removed during conversion of fossil fuels – chemical
lirecycling. Reduction of consumption of hard coal and technical oxygen for the same gas production. Increasing efficiency and decreasing emission from the process. Residence time of particles in the reaction zone promoting Boudouard reaction. I it ” h „In situ” char. Filling a market gap for gasification rectors with a capacity of 50-150 MW. Increased reactor efficiency. Increase of conversion degree of coal as a result of pressure influence on the process kinetics.
Ballroom B – Session 8:Gasification kinetics & experiments, 16:10-16:30
Ballroom B – Session 17: Entire concepts II, 13:20–13:40p ,
Pilot scale studies on coal gasification in a circulating fluidised bed reactor with CO2 addition as a gasifying agent (Aleksander Sobolewski, Institute for Chemical P i f C l P l d)
p ,
Concept of demonstration plant for methanol synthesis by CO2 enhanced gasification of coal in fluidised bed reactor (Tomasz Chmielniak, Institute for Chemical P i f C l P l d)
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Processing of Coal – Poland) Processing of Coal – Poland)
The scope of ICThe scope of IChhPPWW research concerning research concerning on on lid f llid f l hi hhi h t tt t iisolid fuels solid fuels high high temperaturetemperature conversionconversion
Testing of solid fuels properties and
their kinetics in
Gasification of solid fuels in CO2 in the pressurized circulating fluidized bedParameters:Pressure: 1,6 MPatheir kinetics in
laboratory scaleCoal stream: 100 kg/hGasification agents: O2, CO2, steam
Non-pressurized gasification of solid fuels (IPPS)fuels (IPPS)Parameters:Pressure: 0,1 MPaCoal stream: 200 kg/hGasification agents: air, CO2, steam
Modelling of gasification processusing CFD tools &
Tests on pilot andthermodynamiccalculation
Tests on pilot and technical scale
installations
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ComputationalComputational PParticle article FFluidluid DDynamicynamic(CPFD)(CPFD) i l tii l ti
Computational geometry and model setup
(CPFD)(CPFD) simulation simulation
• 102 432 mesh elements • Coal density – 1200 kg/m3
• Char density – 650 kg/m3
100Particle Size Distribution
y g
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ight, %
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Cumulative we
Test 1 coal
Test 1 char
Test 2 coal
Test 2 char
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0 0,2 0,4 0,6 0,8 1 1,2Particle radius, mm
Test 3 coal
Test 3 char
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O ti ditiO ti ditiTest Test No.No. UnitUnit Test 1Test 1 Test 2Test 2 Test 3Test 3
C l fl t kg/h 29 73 29 38 32 46
Operating conditionsOperating conditions
Coal mass flow rate kg/h 29.73 29.38 32.46Gasifying agent mass flow rate kg/h 61.93 80.2 72.04
Gasifying agent composition (mass fractions):N2 ‐ 0.17 0.17 0.16CO2 ‐ 0.63 0.66 0.68O2 ‐ 0.20 0.17 0.16
G if i t t oC 142 149 148Gasifying agent temp. oC 142 149 148
Gasification zone temp. oC 839 671 655
Gasification pressure MPa 0.38 0.440 0.42Ultimate analysis
W % 11.7 12.20 10.70A % 9.74 9.73 9.07C % 54 53 40 54 10C % 54 53.40 54.10H % 3.9 3.82 4.02N % 0.57 0.58 0.57O % 19.93 20.08 21.39
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S % 0.17 0.18 0.16
CPFDCPFD governinggoverning equationsequationsCPFD CPFD governinggoverning equationsequationsFluid phase continuity Fluid phase continuity equatioequationn LiouvilleLiouville equatioequationn
Fluid phase momentum Fluid phase momentum equatioequationn The acceleration of a particleThe acceleration of a particle
Fluid phase energy Fluid phase energy equationequation The equation for solid movement The equation for solid movement
The individual gas The individual gas speciesspecies transport transport equationequationThe The lumpedlumped--heatheat equationequation for the for the particleparticle
The The gasgas mass mass productionproduction raterate The The conservativeconservative energyenergy exchangeexchange fromfromthethe particleparticle phasephase toto thethe fluidfluid phasephase
InterInterphasephase momentummomentum transfertransfer
thethe particleparticle phasephase toto thethe fluid fluid phasephase
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DevolatilizationDevolatilization andand moisturemoisture releasereleaseDevolatilizationDevolatilization and and moisturemoisture releaserelease
Heterogeneous
reactions Products
O O
Volatiles
DEVOLATILIZATION AND MOISTURE RELEASECarbon
Ash
MoistureH2
COCO2 Homogeneous
P d t
CH4
CO
H2OTAR
reactions Products
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DevolatilizationDevolatilization andand moisturemoisture releasereleaseDevolatilizationDevolatilization and and moisturemoisture releasereleaseSciazko model
Mass flow rateMass flow rateof releasedvolatiles
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ChemicalChemical equationsequations andand reactionreaction ratesratesChemicalChemical equationsequations and and reactionreaction ratesrates
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Input parameters in the CPFD simulationInput parameters in the CPFD simulationInput parameters in the CPFD simulationInput parameters in the CPFD simulation
Particle-to-wall N l t ti ffi i t 0 3Particle-to-wall interaction
Normal retention coefficient, en 0.3
Tangential retention coefficient, et 0.99
Particle normal stress P t t f th lid h t d l P 1 PParticle normal stress model
Pressure constant of the solid-phase stress model, Ps 1 Pa
Dimensionless constant of the solid-phase stress model, γ 3
Di i l t t f th lid h t d l θ 10 8Dimensionless constant of the solid-phase stress model, θ 10-8
Solver setting Maximum momentum redirection from collision 40%
Time step t 1 10 4 sTime step, t 1x10-4 s
Time, t 250 s
Beginning time for average 150 sBeginning time for average 150 s
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ResultsResults InstantaneousInstantaneous//TimeTime averageaverage ParticleParticle VolumeVolume FractionFractionResultsResults InstantaneousInstantaneous//TimeTime--averageaverage ParticleParticle Volume Volume FractionFraction
Test 1Test 1 Test 2Test 2 Test 3Test 3Test 1Test 1 Test 2Test 2 Test 3Test 3
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ResultsResultsInstantaneo sInstantaneo s MassMass F actionF action ofof GasGas SpeciesSpeciesInstantaneousInstantaneous Mass Mass FractionFraction of of GasGas SpeciesSpecies
Test 1Test 1 Test 2Test 2 Test 3Test 3 Test 1Test 1 Test 2Test 2 Test 3Test 3
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T=839 oC p=0.378MPaGg=62kg/h
T=671 oC p=0.44MPaGg=80kg/h
T=655 oC p=0.42MPaGg=72kg/h
T=839 oC p=0.378MPaGg=62kg/h
T=671 oC p=0.44MPaGg=80kg/h
T=655 oC p=0.42MPaGg=72kg/h
ResultsResultsGasGas SpeciesSpecies MassMass F actionF actionGasGas SpeciesSpecies Mass Mass FractionFraction
Test 1Test 1 Test 2Test 2 Test 3Test 3Test 1Test 1 Test 2Test 2 Test 3Test 3
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T=839 oC p=0.378MPaGg=62kg/h
T=671 oC p=0.44MPaGg=80kg/h
T=655 oC p=0.42MPaGg=72kg/h
T=839 oC p=0.378MPaGg=62kg/h
T=671 oC p=0.44MPaGg=80kg/h
T=655 oC p=0.42MPaGg=72kg/h
ValidationValidation ofof resultsresultsValidationValidation of of resultsresults
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Test 1Test 1
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mol f
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0CH4 CO CO2 H2 N2 TAR
0CH4 CO CO2 H2 N2 TAR
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0CH4 CO CO2 H2 N2 TAR
ValidationValidation ofof resultsresultsValidationValidation of of resultsresults70
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H2CH4
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mol fraction of components (experimental), %
ConclusionsConclusionsConclusionsConclusions
• Developed model coresponds to changes in processDeveloped model coresponds to changes in processparameters and give results with a similar degree ofagreement for all three tests.
• The gas composition at the gasifier outlet using CPFDmodel is comparable with experimental data. Therelative error of mol fraction is lower than 20%.
• The highest temperature (Test1) gives the highestd ti f i l d t (CO H )production of crucial gaseous products (CO, H2).
• The three-dimensional models and simulations providea promising way to simulate the coal gasification ina promising way to simulate the coal gasification influidized beds.
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AcknowledgementsAcknowledgementsAcknowledgementsAcknowledgements
ThankThank youyou for for youryour attentionattention!!
The research was carried out within the project "Development of coal gasification technology for high-p g gy g
efficiency production of fuels and energy", Task No. 3 of the Strategic Program for Research and Development:
"Advanced energy generation technologies" funded by the
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Polish National Center for Research and Development.
