energetic & non-energetic use of low-grade fuels ... · pdf fileenergetic &...

Christian Hasse KAUST – Future Fuels Workshop March 9th 2016

Energetic & non-energetic use of low-grade fuels Scientific challenges from a combustion point of view

http://www.ntfd.tu-freiberg.de

Introduction - University

Freiberg

Berlin

Frankfurt

Munich

Dresden

Hamburg

-  Founded in 1765 (oldest school of mines)

-  Famous scientists: Humboldt, Werner, Winkler, Lomonosov

-  Discovery of Indium and Germanium

-  Approx. 1200 scientific staff / 5000 students

Utilization

Low Grade Fuels Gas -- Liquid – Solids

Energetic Non-energetic

Heat

Electricity

Disposal non-

catalytic catalytic

Gasification / POX Combustion

Syngas à high grade fuels

plusbiological route✗

✗✗✗

✗

✗ ✗

Overview

1.  Low Grade Fuels

2.  Energetic Use

3.  Non-energetic Use

Utilization

Reasons for utilization: 1.  Long-term increasing trend for the prices of conventional fuels,

despite major “short-term fluctuations” 2.  Low-cost disposal routes for many waste materials/low calorific

gases (“CH4 are much worse than CO2 emissions”) 3.  Growing interest in the use of biomass for energy production

Utilization of low-grade fuels


Conversion to high-grade fuel (H2-rich gas) by gasification

Combustion for heat and/or electricity supply

Definition

Low-grade fuels Def.: “Materials that have an energetic content that may be recovered by direct

or indirect processes but which is significantly lower than that of normal fossil fuels. The lower energy content may be due to low inherent potential in the organic material, or by the ‘dilution’ of the carbonaceous material by mineral matter and water. Also, the fuel may be low grade because it has high concentrations of pollutant precursors such as sulfur. Some low grade fuels, such as waste plastics, have an intrinsically high energy content but are most frequently encountered in a diluted form such as refuse-derived fuel.”

solid liquid gaseous Biomass (bark, saw dust) Heavy fuel oil (HFO) Blast furnace gas (Top gas) Plastic waste, MSW Soy molasses Vent gas Fiber residue Vinasse (Spent wash) Corex gas

Sewage sludge Formaldehyde gas

Source: http://www.iea-coal.org.uk/site/2010/publications-section/newsletter-information/current-newsletter/ whats-a-good-way-to-use-low-grade-fuels-with-coal?

Fuels

0 20 40 60 80

100 120 140 160

Higher heating value in MJ/kg

Basics of gaseous low-grade fuels

-  Examples for gaseous low-grade fuels (lean gas): -  Blast furnace gas (top gas) -  Corex gas -  Formaldehyde gas -  Vent gas -  CO gas

-  Relevant properties for energetic or non-energetic use: -  Available in large quantities as by-product of steel production or chemical

industry -  Contains considerable amount of inert gases e.g. N2, CO2, H2O -  Limited amount of combustible ingredients (CO, H2) ~25 % vol. → Hi ≈ 2 – 15 MJ/Nm3 (natural gas Hi = 31 – 41 MJ/Nm3)

-  Available often only on low pressure levels

Steel production

Chemical industry

Basics of liquid low-grade fuels

Brent

Brent Assay Data: Chevron Crude Oil Marketing & J.P. Wauquier: Petroleum Refining. Part 2: Separation Processes, 2000

Paraffin: 10 % Aromatics 24% Resin 54 % Asphaltene: 12 %

wikipedia

Pyrolysis Liquids

Pyrolysis - Liquids-  Comparable approach to pyrolysis

of solid feedstocks-  Thermal decomposition of labile

bridges in long-chain hydrocarbons → Formation of fragments à Depolymerization

-  Formation of a char shell around the oil droplet with interacting liquid and gaseous phase inside

-  Evaporation of light fragments through the porous char shell

-  Crosslinking and reticulation of fragments to char shell during transport (coking) → Formation of char lattice

Source: E. Ranzi et al., Progress in Energy and Combustion Science (2001), 99–139

CH3 +

Evaporation

Source: Keller et al, Journal of Engine Research, 2015

Vapor-liquid equilibrium n-hexane/ethanol

UNIFAC

Ethanol 1 x CH3 1 x CH2 1 x OH

Char Conversion: Liquids

Char conversion – Liquids

-  Thermal conversion of carbon in the char lattice by heterogeneous surface reactions

-  Conversion process similar to char conversion of solid feedstocks → formation of a highly porous, solid soot particle after pyrolysis à cenospheres

-  Determination of conversion process by similar phenomena

O2, H2O CO2, H2

CO, CH4 CO2, H2

Soot formation

Excursion: Soot formation mechanisms -  Incomplete conversion (burnout) of char particles / cenospheres

(char with ash) 1.  Heating without evaporation 2.  Formation of volatiles by evaporation and pyrolysis (e.g. cracking,

dehydration possibly without reaching the boiling point) 3.  Boiling of droplet 4.  Char formation 5.  Incomplete char burnout (Overlay with swelling)

λ = 0.13

50 µm Pore Gas

Liquid

Char shell

Source: A. Bader et al., 7th International Freiberg/Inner Mongolia Conference Huhhot, China (2015)

Soot formation

Soot formation on basis of primary soot (gas phase reactions) 1.  Formation of ethine from hydrocarbons 2.  Reaction of ethine with CH or CH2 radicals under formation of C3H3 3.  Ring formation by recombination and rearrangement 4.  Ring growth 5.  Nucleation and coagulation

λ = 0.34

50 µm

Mixture of

Fuel + Oxidizer Figure O2

H2 H2O

CO CO2

Source: H. Bockhorn (ed.), Soot Formation in Combustion. Mechanisms and Models, Springer-Verlag (1994). A. Bader et al., 7th International Freiberg/Inner Mongolia Conference Huhhot, China (2015)

Reaction time Honeycomb soot

2. Basics – Utilization








3.3 Energetic use

Laminar flames Wrinkled flames

Corrugated flames

Thin reaction zones

Broken reaction zones

-  Re=1

Turb

ulen

t vel

ocity

/ La

min

ar b

urni

ng v

eloc

ity

Integral turbulent length scale/ Laminar flame thickness

Peters-Borghi Diagram

3.3 Energetic use

Application of gaseous low-grade fuels: -  Gas burner -  Shell boiler -  Water tube boiler -  Thermal oil heater -  Waste incineration -  Steam generator

-  Hot gas generator / Combustion chamber -  Combined heat and power (CHP) generation for local, district

& process heat + electricity -  Gas turbine -  Gas engine

Source: www.saacke.com/de/home/ www.powergen.gepower.com/

Non-Energetic Use








Non-Energetic Use: Gasification

Low-grade fuel CO/H2

High-grade fuel

Fuel upgrading

Gasification is a technology for the non-energetic use of fuels!

Non-Energetic Use: Gasification

Def.: thermo-chemical conversion of energy carriers with a reactant into combustible gases

Coal Peat

Wood MSW HFO

Natural gas Special gas

Refinery residue Vents

Top gas …

Gasification

CO H2 (CH4)

Electricity Heat Methanol Fuel Ammonia Town gas Hydrogen SNG Reduction gas Oxo-alcohols …

Gasification Conditioning Raw gas

Gasification agent

Feedstock Clean gas

Ash/slag H2O, tar, dust, CO/H2, H2S, etc.

Synthesis gas

Hydrogen

Reduction gas

Fuel gas

MeOH synthesis

DME synthesis

FT synthesis

SNG synthesis

Oxo-alcohol synthesis CO/H2 = 1:1

CO/H2 = 1:2

CO/H2 = 1:1-3

CO/H2 = 1:1.7-2.5

Non-Energetic Use: Chemical Routes

Non-Energetic Use: Processe Variants

Autothermic partial oxidation with burner

Allothermic using steam reforming in tube furnaces

Catalytic Catalytic Non-catalytic

Autothermal- reforming / Lurgi Topsoe

Quench cooler Waste heat boiler

Lurgi reformer Foster Wheeler KTI Lummus

Uhde Topsoe Linde

Steam reforming with downstream catalytic partial oxidation

Koppers-Totzek MPG / Lurgi Texaco (→ GE) SGP / Shell

Combined reforming / Lurgi

Examples of Gasification Reactors

Source: Lurgi

Refining residues Light and heavy oils Natural gas Oil coke Orimulsion Tar Chemical waste Slurries

Feed material Products

Carbon monoxide Hydrogen Electricity (IGCC) Methanol Ammonia Oxo alcohol

By-products -  metal oxide -  sulfur

Oxygen

Steam

Syngas

H2 + CO

Operating at Φ = 2-3 (very rich)

Mixing of combustion products and unreacted fuel

Autothermal non-catalytic partial oxidation

Scientific challenges in POX/Gasification

Phenomenology / BC - Hot flame with pure O2 (up to

3000 K), no N2 - Hot reactor walls - Endothermic post flame conversion

zone, fuel pyrolysis (1400-1800 K)

Important effects - Diffusion in the reaction zone - Radiation (gas, walls, optical

thickness, …) - Fast oxidation reactions vs. slow

post flame conversion reactions - Turbulence-Chemistry-Interaction

Scheme of a large-scale gasifier

Gasification / Partial Oxidation Reactor

KAUST: Gasification and Combustion

Yesterday, after the poster session in the KAUST library…

Not near the combustion books

… that is a difficult start for a combustion person

What a Combustion Guy will ask

-  Do the combustion models for reactive flows work for partial oxidation/gasification?

-  Turbulence-Chemistry Interaction

-  Differential diffusion

-  Radiation

-  Chemical Kinetics

The significant differences to air combustion trigger a number of interesting questions

Model Validation and Application Strategy

“From laboratory-scale flames to full-scale reactors”

Vascellari, M.; Xu, H.; Hartl, S.; Hunger, F., Hasse, C., Chemical Engineering Science, 134, 694–707 (2015)

Fundamental research

Technology

turbulent POX flame

laminar POX flame HP POX

From Partial Oxidation Science to Partial Oxidation technology


Lei et al., CrystEngComm, 12:511-516, 2010

Low-magnification SEM image of AlN microtrees with multipede branches. (b) High-magnification SEM image of a microtree with multipede branches. (c) and (d) High-magnification SEM image of the typical multipede branches. (e) TEM image of the typical multipede branches. (f) HRTEM lattice image of a single nanorod of a branch nanostructure (square domain in (e)). Inset in (f) is fast Fourier transform (FFT) of the image.

Factor 25 000

turbulent POX flame



“From POX Science to POX Technology”

Fundamental research

Technology

turbulent POX flame


Vascellari, M.; Xu, H.; Hartl, S.; Hunger, F., Hasse, C., Chemical Engineering Science, 134, 694–707 (2015)

Laminar POX Setup

Fuel Oxidizer Composition / mol-frac

CH4: 0.5 CO2: 0.5

O2:1

Temperature / K 300 300

Velocity / ms-1 0.262 0.3

Inverse Diffusion Flame (IDF)

-  detailed chemistry (GRI-Mech) -  detailed transport modeling including Soret -  radiation modeling: detailed RTE and

absorption coefficient investigation

Numerical Setup – Laminar

1.  Stelzner, B. et al.. Proceedings of the Combustion Institute 34, 1045–1055 (2013).2.  Hunger, F., Stelzner, B., Trimis, D. & Hasse, C., Turbulence and Combustion 90, 833–857 (2013)

Laminar POX Flame: Structure


Different reaction regimes with different length-/time-scales Post-flame zone (Φ>1): -  mixing of combustion products and unreacted fuel -  slow reforming reactions Oxidation zone (Φ≤1): -  diffusion flame -  fast oxidation reactions

-  Diffusion Modelling -  Radiation -  Time scales of oxidation and reforming -  Flamelet Modelling -  (Direct Comparison of OH-LIF and Rayleigh Signals

instead of postprocessed quantities)

Combined Experimental – Numerical Investigation

Laminar POX Flame: Flame Structure

-  maximum of T and CO2 in the reaction zone

-  steady increase of CO-  significant amounts of CH4

behind the reaction zone-  slow reaction in the post flame

zone

Combustion

Partial Oxidation

Laminar POX Flame: Endothermic zone

Prüfert, U., Hunger, F., Hasse, C., Combustion and Flame, 161:416-426, 2014.

2-3 orders of magnitude slower chemical reactions in the

endothermic zone

Laminar POX: Inverse Flame Structure


0

0.2

0.4

0.6

0.8

1

0 0.05 0.1 0.15

Norm

aliz

ed L

IF S

ignal

x / m

axis

lean

0

0.2

0.4

0.6

0.8

1

0 0.005 0.01 0.015

r / m

20 mm

lean

0

0.2

0.4

0.6

0.8

1

0 0.005 0.01 0.015

Norm

aliz

ed L

IF S

ignal

r / m

40 mm

lean

0

0.2

0.4

0.6

0.8

1

0 0.005 0.01 0.015

r / m

80 mm

0.8

1

0.04 0.06 0.8

1

0.006 0.008

0.8

1

0.003 0.006

Exp. Num. LIF signal

Num. LIF signal w/o quenchNum. OH mole fraction

direct comparison of OH-LIF signal

Laminar POX Flame: Radiation

Garten, B., Hunger, F., Messig, D., Stelzner, B., Trimis, D., Hasse, C.: Detailed Radiation Modeling of a Partial-Oxidation Flame with Optically Thin and Dense regions, International Journal of Thermal Sciences, 87:68-84, 2014.

dI⌘ds

= ⌘(Ib⌘ � I⌘)

G⌘ =

Z

4⇡I⌘(s) d⌦

r · qR =

Z 1

0⌘

✓4⇡Ib⌘ �

Z

4⇡I⌘(s) d⌦

◆d⌘ =

Z 1

0⌘ (4⇡Ib⌘ �G⌘) d⌘

Radiative Transfer Equation (RTE):

Challenges for POX flames-  determination of the absorption coefficients (properties)-  solution of the RTE

@

@t(⇢h) +r · (⇢uh) = �r ·

IX

i=1

hiji +r · (�rT )�r · qR

Laminar POX Flame: Radiation

Garten, B., Hunger, F., Messig, D., Stelzner, B., Trimis, D., Hasse, C.: Detailed Radiation Modeling of a Partial-Oxidation Flame with Optically Thin and Dense regions, International Journal of Thermal Sciences, 87:68-84, 2014.

Challenges for POX flames-  determination of the absorption coefficients -  solution of the RTE

Radiative Properties-  non-gray effects-  WSGG or SLW

necessary

RTE-  OTM not applicable-  P1/MDA or DOM

necessary

Additional modelling efforts for POX compared to air combustion

Flamelet – CFD Coupling

C(Z,χst), T (Z,χst), Y (Z,χst)

ωC(Z,χst)CFD

Calculation

FlameletCalculation

Flamelet Lookup-TableGeneratorYC(x)

Z(x),Z ′′2(x),C (x)

T (Z(x),Z ′′2(x),C(x)),Yi(Z(x),Z ′′2(x),C(x))Z(x) , Z ′′2(x)

u(x) , Yi(x) , T (x) , ρ(x)

ωYC(Z(x),Z ′′2(x),C(x))

i

FLUT

Coupling of Flamelets and CFD [1]:

[1] Weise, Messig, Meyer, Hasse, Combustion Theory Modelling, 17:411-430 (2013) [2] Weise, Hasse, Parallel Computing, 49:50-65 (2015)

⇢@Yk

@t� ⇢

�

2

@2Yk

@Z2= !k

⇢@T

@t� ⇢

�

2

@2T

@Z2=

1

cp

@p

@t+ qr �

nsX

k=1

!khk

!= !T

flamelet solver

Table generation / coupling -  replaces online chemistry -  large tables -  memory efficient coupling [1,2]

CFD – Flamelet two-way coupling

Laminar POX Flame: FPV Model


COComparison fully-resolved and flamelet solutions

POX flamelets

- POX flamelets can become more complex than combustion flamelets

-  higher dimensions (radiation, multiple streams, etc.)

Laminar POX Flame: Summary

Summary for laminar laboratory-scale POX flame

-  Both the fast oxidation zone and the slow endothermic post-flame zone can be realized in the laboratory flame

-  Time scale analysis reveals two very distinct regimes à important for turbulence-chemistry interaction

-  Detailed diffusion modeling even more important than in air-combustion; Soret effect must be considered

-  Radiation modeling more complex than for standard air combustion; RTE: reabsorption must be considered due to higher optical thickness

-  FPV tabulation also applicable for POX flames



Vascellari, M.; Xu, H.; Hartl, S.; Hunger, F., Hasse, C. Flamelet/progress variable modeling of partial oxidation systems: from laboratory flames to pilot-scale reactors, Chemical Engineering Science, 134, 694–707 (2015)

turbulent POX flame


Experimental Setup

Measurement windows

Fuel: 17.5% CH4 42.5% H2 40% CO2 Oxidizer: 68.0% O2 32.0% CO2

Experiment at Imperial College -  OH-LIF + Rayleigh -  operation in inverse and normal

diffusion flame mode

Hunger, F., Zulkifli, M., Williams, B., Beyrau, F., Hasse, C., Flow, Turbulence and Combustion, in press, 2016.

Rayleigh

Numerical Setup

-  LES flamelet-progress variable approach-  OpenFOAM 2.1.x

LES-FPV

-  Flamelet look-up tables (FLUT)

-  Diffusion flamelet for table generation

-  Beta filtered density function (FDF)

Tabulated chemistry

-  Spatial and temporal discretization: 2nd order

-  Sub-grid turbulence: sigma model

-  Turbulent velocity inlet boundary condition from pipe flow LES

LES


Direct comparison of experimental signals

A different approach

Comparison OH-LIF Rayleigh signal

LES + averag.

modeling of exp. signal

Numerics - discret./interp. -  time step/grid size…

Diagnostics Exp. Signal

Models-  radiation-  chemistry-  turbulence/TCI

Flame Setup


Turbulent POX Flame: Exp-LES Comparison

0.0

0.2

0.4

0.6

0.8

1.0

-0.015 -0.01 -0.005 0

Mean O

H-L

IF r

atio

Radius / m

67 mm

Pos.

2

0 0.005 0.01 0.0150

0.2

0.4

0.6

0.8

1

RM

S O

H-L

IF r

atio

Radius / m

Pos.

3

0.0

2.0

4.0

6.0

8.0

10.0

-0.015 -0.01 -0.005 0

Mean R

ayl

eig

h r

atio

Radius / m

0 0.005 0.01 0.0150

1

2

3

4

5

RM

S R

ayl

eig

h r

atio

Radius / m

Pos.

1

Exp. IDFExp. NDFNum. IDF

Num. NDF

0.0

0.2

0.4

0.6

0.8

1.0

-0.015 -0.01 -0.005 0

Mean O

H-L

IF r

atio

Radius / m

67 mm

Pos.

2

0 0.005 0.01 0.0150

0.2

0.4

0.6

0.8

1

RM

S O

H-L

IF r

atio

Radius / m

Pos.

3

0.0

2.0

4.0

6.0

8.0

10.0

-0.015 -0.01 -0.005 0

Mean R

ayl

eig

h r

atio

Radius / m

0 0.005 0.01 0.0150

1

2

3

4

5

RM

S R

ayl

eig

h r

atio

Radius / m

Pos.

1Exp. IDF

Exp. NDFNum. IDF

Num. NDF

Rayleigh

OH-LIF

Hunger, F., Zulkifli, M., Williams, B., Beyrau, F., Hasse, C., submitted, 2016.

Turbulent POX Flame: NDF-IDF Dynamics

Hunger, F., Zulkifli, M., Williams, B., Beyrau, F., Hasse, C., submitted, 2016.

IDF NDF

Turbulent POX Flame: Summary

-  FPV tabulation also applicable for turbulent POX conditions

-  Flame dynamics can be described sufficiently accurate with LES-FPV

-  Similar modeling strategies can be used for IDF and NDF

-  (Direct comparison between experimental and simulated simultaneous planar Rayleigh and OH-LIF is an suitable way for model evaluation and flame analysis)

Summary for turbulent laboratory-scale POX flame




turbulent POX flame


3.4 Non-energetic use

Source: http://tu-freiberg.de/en/iec/evt/groups/equipment/pilot-plants

Operation conditions: -  Temperature: up to 1450 °C -  Pressure: up to 100 bar -  Scale: 5 MWth -  Mode: catalytic and non-catalytic -  Feedstock:

-  Natural gas → catalytic (ATR) -  Natural gas → non-catalytic (Gas

POX) -  Light oil and HFO → non-catalytic

(Oil POX) -  Atmos. and vacuum residues → non-

catalytic (Oil POX)

HP POX pilot plant in Freiberg

High Pressure POX (HP POX)

Oxidizer Gasification Agent Fuel

m, kg/s 0.1452 0.1491 0.1014

T , K 506.8 657

CH4 0 1

O2 0.837 0

H2O 0.155 0

N2 0.008 0

Z 0.0 1.0

Y

c

0.155 0

Table 2: Input conditions of the HP POX reactor. Concentrations are given as mass fractions.

composed of steam, enters from the intermediate annular section, and the fuel, composed328

of CH4, enters from the external annular section. The mass flow rates, composition and329

temperature of the input streams are reported in Tab. 2.330

4.2. Results331

4.2.1. Analysis of the FLUT332

The P-FLUT was generated using freely propagating premixed flames as previously de-333

scribed. The progress variable is defined as follows: Y

c

= 2YH2+ YH2O

+ 0.6YCO2+ YCO. Y

c

334

is chosen in order to satisfy the requirements described above, and particular attention was335

paid to accurately resolving the partial oxidation process close to the outlet mixture fraction336

(Zout

= 0.388), which is the main goal of this work.337

The temperature and the progress variable source term obtained from the laminar 1D338

premixed flames are shown in the Z-Yc

space in Fig. 8. The lower limit in the plots represents339

the minimum values of Y

c

for a given mixture Z, corresponding to pure mixing between340

the reactants. This condition represents the pure mixing between the reactants without341

reactions. The non-normalized progress variable is set to zero for the fuel inlet (Z = 1),342

while it is set to 0.155 for the oxidizer inlet (Z = 0), corresponding to the mass fraction of343

21

T, K

Z

Yc

Pilot-scale POX reactor Premixed Flamelet Table

global equivalence ratio Φ > 2.5

A CFD guy’s nightmare-  accuracy boundary conditions-  size (multi-scale!)-  outlet only values


HP POX: Results

Slow approach to equilibrium towards outlet

C

C =Yc

� Yc,min

(Z)

Yc,max

(Z)� Yc,min

(Z)

0

0.2

0.4

0.6

0.8

1

CH4 CO CO2 H2 H2O Yc

Yi

ExpFPV

Overall good agreement but notable differences for CH4, CO2 and H2O-  FPV model ?-  gas phase chemistry ?

T, K

Outlet values FPV results

Small temperature gradients in endothermic zone


DNS of Post-Flame Endothermic Zone

Source: J. Caudal et al., Fuel Processing Technology 134 (2015) 231–242

DNS – YCO DNS vs. FPI

tabulation Setup

-  slow chemical reactions under fuel rich conditions

-  (Premixed) Flamelet tabulation in good agreement with DNS à FPI/FPV well suited for large-scale RANS/LES

-  EDC does not work (what a surprise ….)

Conclusion

POX Chemistry: Setup and Objectives

Köhler, M., Oßwald, P., Xu, H., Kathrotia, T., Hasse, C., Riedel, U., Chemical Engineering Science, 139:249-260, 2016.

Objectives 1.  Compare the species profiles to modeling results with well-

established kinetic mechanisms 2.  provide benchmark data for POX conditions

DLR MBMS

Test case I II III IV V

Details CH4-Basis +CO2 +CO, +CO2 +C2H2 high +C2H2 low

Equivalence ratio 2.5 2.5 2.5 2.5 2.5

C/O 0.625 0.556 0.571 0.667 0.634

Ar 9950 9950 9950 9950 9950

CH4 25 25 25 20 25

O2 20 20 25 18 20.5

CO 0 0 25 0 0

CO2 0 25 50 0 0

C2H2 0 0 0 2 0.5

5 prototypical POX compositions

Collaboration with DLR Stuttgart (Uwe Riedel)

POX Chemistry: Results

Köhler, M., Oßwald, P., Xu, H., Kathrotia, T., Hasse, C., Riedel, U., Chemical Engineering Science, 139:249-260, 2016.

Quotes: 1.  “Prediction of the global chemistry shown for the major species is mixed at best. (….) the

CO/CO2 mole fraction ratios reveal arbitrary results from the investigated models.“ 2.  “The comparisons reveal significant differences in the model predictions among

themselves, underlining the relevance of this unique data set for mechanism optimizations”

1200 1400 1600 18000

2

4

Tes

t Cas

e V

x i [10

-3]

T [K]

GRI 3.0 Chernov_C2 USC-II Chernov Exp. Eq.CO CO2 H2

1200 1400 1600 18000

2

4CH4/O2 C2H2=0.5sccm φ=2.5 Ar=99.5%

x i [10

-3]

T [K]

GRI 3.0 Chernov_C2 USC-II Chernov Exp.O2 CH4

1200 1400 1600 18000

2

4

Tes

t Cas

e IV

x i [10

-3]


1200 1400 1600 18000

2

4CH4/O2 C2H2=2sccm φ=2.5 Ar=99.5%

x i [10

-3]


1200 1400 1600 18000

2

4

6

8

Tes

t Cas

e III

x i [10

-3]


1200 1400 1600 18000

2

4

6

8CH4/CO2/CO/O2 φ=2.5 Ar=99.5%

x i [10

-3]


1200 1400 1600 18000

2

4

Tes

t Cas

e II

x i [10

-3]


1200 1400 1600 18000

2

4

CH4/CO2/O2 φ=2.5 Ar=99.5%

x i [10

-3]

GRI 3.0 Chernov_C2 USC-II Chernov Exp.O2 CH4 H2O

1200 1400 1600 18000

2

4

Tes

t Cas

e I

x i [10

-3]


1200 1400 1600 18000

2

4

CH4/O2 φ=2.5 Ar=99.5%

x i [10

-3]

GRI 3.0 Chernov_C2 USC-II Chernov Exp.O2 CH4 H2O

1200 1400 1600 18000

3

6

1200 1400 1600 18000

3

6

1200 1400 1600 18000

3

6

1200 1400 1600 18000

1

2

3

1200 1400 1600 18000

1

2

3

1200 1400 1600 18000

1

2

3

1200 1400 1600 18000

4

8

1200 1400 1600 18000

4

8

1200 1400 1600 18000

4

8

C2 H

6C

2 H4

C2 H

2

GRI 3.0 Chernov_C2 USC-II Chernov Exp.C2H2

x i [10

-4]

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Major species Intermediates

Summary

-  Review of some characteristics of gaseous, liquid and solid low grade fuels

-  Both energetic and non-energetic routes are widely used

-  Focus on non-energetic use à Gasification / Partial Oxidation (POX)

-  Differences to air-combustion -  Systematic approach for model development and

application: from laminar flames to large-scale reactors-  Adaption of combustion modeling framework and

strategies for POX conditions -  Gas-phase chemistry for very fuel-rich conditions is

one the weakest links currently

Financial support by

-  Federal Ministry of Economic Affairs and Energy BMWi (0327773I)

-  Federal Ministry of Education and Research BMBF (03Z2FN11)

-  Saxon Ministry of Science and Fine Arts SMWK and the European Union (100097882)

-  the German Research Foundation DFG (Ha 4367/3-1)

energetic & non-energetic use of low-grade fuels ... · pdf fileenergetic &...

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