Gasification Systems Training Workshops Presented to: Reliance - - PowerPoint PPT Presentation

Confidential

Project 1481

Ash Behavior in E-Gas Gasification Systems Training Workshops

Presented to: Reliance Industries Ltd.

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Presentation Overview

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Agenda for Workshop

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Microbeam – description of company

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Capabilities

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Databases

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Tools – Analysis, testing, mechanisms, and modeling

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Workshop goal and objectives

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Subject Areas

1.

Fuel impurities and measurement

2.

Impurity transformations in gasification systems

3.

Impurity transport and deposit growth in gasification systems

4.

Managing/predicting ash behavior in gasifiers and syngas coolers

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Day 1. Workshop Overview and Subject Area 1. Fuel impurities and measurement

900 Introductions 930 Workshop Overview 1030 WS - 1 - Fuel Impurities: Fuel impurities - abundance and forms in Fuels 11:30 WS - 2 - Fuel Impurities Measurement: Fuel impurities - Methods of measurement – Overview 1230 Lunch 1330 WS - 3 - Standard methods of Measurement - Standards for analyzing fuel impurities 1430 WS - 4 - Advanced methods (minerals) - Scanning electron microscopy and x-ray diffraction 1530 Break 1600 WS - 5 - Advanced analysis (organic bound) - Chemical Fractionation 1730 WS - 6 - Review literature on subject area -- Discussion/Questions

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Day 2. Subject Area 2: Impurity transformations in gasification systems

900 Introductions 930 WS - 7 - Mineral forms - Thermal properties of mineral phases 1030 WS - 8 - Organic impurity forms - Thermal properties of organically associated elements 1130 WS - 9 - Gasification process - Partitioning impacts - slag formation/deposit growth 1230 Lunch 1330 WS - 10 - Impurity transformations-coarse ash particle formation and coalescence - coarse particle formation 1430 WS - 11 - Impurity transformations-fine particle formation through release of

• rganically associated elements and vaporization/condensation

1530 Break 1600 WS - 12 - Impurity transformations-ultrafine particle formation - Homogeneous and heterogeneous condensation

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Day 3. Subject Area 2: Impurity transformations in gasification systems (continued)

900 Introductions 930 WS - 13 - Ash particle size composition - Particle size composition distribution (PSCD) of ash 1200 Lunch 1300 WS - 14 - Fuel type Impacts on PSCD - Impacts of coal rank and fuel properties 1500 Break 1530 WS - 15 - Review literature on subject area 2

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Day 4. Subject Area 3: Impurity transport and deposit growth in gasification systems

900 Introductions 930 WS - 16 - Intermediate Transport - Ash particle and vapor phase transport mechanisms 10:30 WS - 17 - Bonding phases/flow behavior - Chemistry and physical properties of phases responsible for ash bonding/sticking/flow 1200 Lunch 1300 WS - 18 - Corrosion layer - Steel/Alloy corrosion processes 1500 Break 1530 WS -18 - Continued

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Day 5. Subject Area 3: Impurity transport and deposit growth in gasification systems (Continued)

900 Introductions 930 WS - 19 - Ash particle sticking mechanisms - Sticking mechanisms - surface and particle properties - deposit growth 1030 WS - 20 - Initial layer composition - Impacts of vapor phase species on initial layers 1200 Lunch 1300 WS - 21 - Ash particle sticking -- Particle properties 1500 Break 1530 Discussion/ Questions

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Day 6. Subject Area 3: Impurity transport and deposit growth in gasification systems (Continued)

900 Introductions 930 WS - 22 - Sintering processes - General sintering processes in gasifiers 1030 WS - 23 - Sintering processes - high temp Sintering with reactive liquids - silicate based sintering/crystallization 1200 Lunch 1300 WS - 24 - Sintering processes - Low temp Sintering with less reactive liquids - sulfide and halogen based sintering 1500 Break 1530 WS - 25 - Sintering processes - Gas/Solid Sintering with less reactive liquids - pore filling - molecular cramming

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Day 7. Subject Area 3: Impurity transport and deposit growth in gasification systems (Continued)

900 Introductions 930 WS - 26 - Deposit thermal properties - Heat transfer through deposits - Dependency on deposit properties 1030 WS - 27 - Development of a captive surface -- Deposit surface properties - sintering liquid phase formation - slag flow behavior 1200 Lunch 1300 WS - 28 - Review literature on subject area -- Literature in this area will be provided and reviewed 1500 Break 1530 General discussion – review of key chemical and physical process important to managing/predicting

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Day 8. Subject Area 4: Managing/predicting ash behavior in gasifiers and syngas coolers

900 Introductions 930 WS - 29 - Past evolution of PC and CFB - Fuel type impacts on system design - Gasifier/syngas coolers 1030 WS - 30 - Ash formation -- Models to predict the particle size composition distribution in gasification systems 1130 WS - 31 - Slag flow -- Models to predict the flow behavior of ash/slag (T250, T80, TCV) 1230 Lunch 1330 WS - 32 - Transport models -- Models to predict the transport of ash particles to surfaces 1500 Break 1530 WS - 33 - Growth/sintering - Models to predict ash particle sticking behavior/growth/strength development

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Day 9. Subject Area 4: Managing/predicting ash behavior in gasifiers and syngas coolers (continued)

900 Introductions 930 WS - 34 - Deposit thermal property -- Models to predict deposit thermal properties 1030 WS - 35 - Integrated models -- Application of combustion system models to gasification - CFD based 1130 WS - 36 - Simplified integrated models - Advanced indices for gasifiers/syngas coolers 1230 Lunch 1330 WS - 37 - Deposit shedding - Impacts of fuel properties and

• perating parameters

1500 Break 1530 WS - 38 - On-line cleaning -- Force required to remove deposit

• peak impact pressure

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Day 10. Subject Area 4: Managing/predicting ash behavior in gasifiers and syngas coolers (continued)

900 Introductions 930 WS - 39 - On-line cleaning - Effectiveness of soot blower, horn, pulse detonation, thermal shock etc 1030 WS - 40 - Additives to manage fouling - Overview of additives such as clays, bauxite, kaolinite, magnesium oxide etc 1130 WS - 41 - Synthetic slag formulations - Synthetic slags to

• ptimize slag flow and minimize ash deposition

1230 Lunch 1330 WS - 42 - Laboratory methods -- Laboratory support for Reliance Gasification Technologies 1500 Break 1530 WS - 43 - Review literature on subject area

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Microbeam Technologies Inc.

 Commercial spin-off from the University

• f North Dakota

 Mission

 Provide advanced combustion and

gasification system analysis and consulting services to minimize the impact of fuel impurities on combustion and gasification system performance

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Experience Base

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Conducted over 1480 projects for utilities, coal companies, power system developers, and research

• rganizations worldwide since 1992

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Advanced tools to predict the impacts of fuel impurities

• n gasification and combustion system performance

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Analysis of fuels, fly ash, corrosion products, deposit characteristics ~10,000 samples

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Behavior of inorganic components in combustion and gasification systems

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Characterization and optimization of system operating conditions

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Experience – Plant Performance

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Fuel properties – Coal (brown to anthracite), petroleum (coke and fuel oils), biomass (wood, grasses…), waste wood (hog fuels), waste paper

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Sorbent properties – limestone attrition and reactivity testing

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Plants

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Combustion – PC, cyclone, fluid bed

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Air pollution control systems – NOx (staging, SNCR, SCR), SO2/SO3 (SDA, WFGD, DSI), particulate (ESP, FF), Mercury (oxidation, sorbents)

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Gasification – entrained flow, fixed bed, fluid bed, transport reactors

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Advanced systems – chemical looping

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Examples of Recent Projects

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Cyclone fired combustion systems

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Impacts of NOx reduction strategies on slag flow, ash partitioning (particulate loading), fouling/slagging

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Fuel properties – fuel selection and blending

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Entrained flow gasification

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Synthetic slag formulations for Pet coke fired slagging gasifiers

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Syngas cooler fouling

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Pulverized coal fired systems

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Blending to manage fuel properties

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Slag deposit strength for ash handling systems

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Particulate control – ash resistivity and cohesivity

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Fluidized bed combustion

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Small scale combustion testing - Ash properties – pH and leachability

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Bed agglomeration management for pet coke, biomass, waste combustion

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Mercury control

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Impacts of oxidizing agents – Hg capture and corrosion issues

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Additives for reduction of fine particulate and deposit formation

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Roadmap – Technology applications for the ND lignite industry

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Microbeam Capabilities

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Fuel characterization techniques

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Computer-controlled scanning electron microscopy

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Chemical fractionation

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Deposit/slag characterization techniques

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Morphology

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Scanning electron microscopy point count – viscosity/porosity

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High temperature equipment

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Slag flow

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Refractory corrosion testing – static and dynamic testing

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Pilot and full-scale testing equipment

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Syngas cooler fouling simulator

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Deposit recovery

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Limestone attrition and reactivity testing

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Plant performance assessment

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Sampling fly ash (impactors/filters), slag, deposits

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Modeling and predictive methods

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Viscosity versus temperature for slag

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Predictive indices for slag flow, ash deposition, ash handling, particulate control

Training

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Impacts of fuel properties on plant performance

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Advanced analysis methods to analyze fuels and associated materials

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Workshop Goal and Objectives

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Goal is to provide Reliance Industries personnel with a fundamental understanding of the behavior of ash- related materials that will facilitate reliable and efficient

• peration of the E-Gas gasification system.

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Objectives include providing the following information

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Detailed workshop summary document

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Copies of slides used in the lectures

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Presentation of lectures on specific topics

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Research papers and other reports.

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Fuel Properties

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• 1. Initial Fuel

Coal

Biomass Petroleum Coke

Transformations – Fuel Impurities

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Ash formation during Oil/Petcoke Conversion

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Oil Ash Particle Size Distribution

Miller and Linak, 2002

Transport Mechanisms

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Ash Transport to Heat Transfer Surfaces

 The transport of intermediate ash species

(inorganic vapors, liquids, and solids) is function of:

 State and size of the ash species  System design – burner type, heat transfer

surface configuration

 System conditions such as gas flow patterns,

gas velocity, and temperature

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Ash Transport Mechanisms

eddy

Sticking

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Heat transfer surface Ash

Fe0 Fe0 Fe0 Fe0 Fe0 Fe0 Fe0 Fe0

Fe2+

Fe0 Fe0

Fe2+ Fe2+ Fe2+

S2- S2- S2- S2- S2-

Growth – Bonding Phases

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Ash intermediate transport and deposition

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Vapor phase Homogeneous condensation Heterogeneous condensation Na S Cl K P Fe Ni Zn SO2 SO3 Aerosols (0.02 – 0.2 µm) Fuel Impurity Derived Materials from Combustion Process – Vapors, liquids, and solids Quartz Clay Pyrite Calcite Organic Ca Coalescence Fragmentation shedding Steel Tube Corrosion and bonding layer - Gas-solid reaction Sulfide rich layer

Layered Deposit Transport Process Ash Intermediates – gas liquid and solid

Diffusion Thermophoresis Inertial Impaction Sintered layer - Gas-solid reaction, molecular cramming-expansion due to reaction of S with Deposited particles, Ostwald ripening Sulfate coated particles and sulfate pore filling SO2/ SO3

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Bonding/Sticking Phases

Phase Abundance

1200 ºF

FeS (1810 ºF) ZnS (>1450 ºF) Na-FeS (~1380 ºF)

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Sintering – strength development

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Viscosity versus temperature for day 2 ash

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Significant strength would develop at temperatures above 1900 ºF. The materials would flow at about 2200 ºF

Measured T250 – 2045 ºF

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Sintering

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Transport of Particles <5 µm – Forming the Initial Deposit Layers

Benson and others, 1993

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Formation of Deposit Outer Layers Via Inertial Impaction and Capture Due to a Captive Liquid Phase

Benson and others, 1993

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Transport of particles <5 µm, forming the initial deposit layers

Steel Tube (T = 540°C/1000°F)

Fly Ash and Products of Combustion

T

g a s

= 2000°F V

g a s

= 25 ft/sec

Vapor-Phase and Small-Particle Diffusion Flue Gas Boundary Layer, Particle Size <5 m

Benson and others, 1993

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Sticking Probability – ash particle size

Huang and others, 1996

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Transport and sticking of inner sinter layer or intermediate layer of the deposits

Fly Ash and Products of Combustion

Rebounding Particles Liquid in Deposits Due to Temperature Increase

Benson and others, 1993

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Formation of deposit outer layers via inertial impaction and capture due to a captive liquid phase

Molten Captive Surface

Benson and others, 1993

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Captive surface

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Amorphous material filling spaces between fly ash particles

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Melting, assimilation, and chemical interactions

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Captive surface

Benson and others, 1993

Thermal Properties

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Effect of temperature and ash properties on thermal conductivity

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The ash materials A, B, C, and D represent ash materials

• f varying composition.

Ash A has sodium content of 5% The slag – was molten The particles – not sintered – represents the boundaries for thermal conductivity

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Deposit Strength and Porosity

Kaliazine and others, 1997

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Mechanism of Heat transfer and deposit growth

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Ni and Others*

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Slag formation and Flow

Syngas

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Slag Layer Thickness Calculation

Solid Slag Liquid Slag

Twall T250 Tsurface, gas

Vapors, fine, and non- impinging particles Heat Flux- Volatiles and Char Gasification

XT = k • (Tgas – Twall) / H

Assim Slag

Xs = k • (T250 – Twall) / H

TAssim

Xa = k • (Tgas – T

assim) / H

Xl = XT - Xa - Xs

Syngas Cooler Wall

Slag Layer Formation Model

Solid Slag Liquid Slag

Twall T250 Tsurface, gas

Impingement Rate (char + ash particles) Gas Slag Flow

xi

viscosityi

Shear forcei = density • g • xi Slag flow ratei = Sheari • xi / Viscosityi

Deposition rate = Ash impingement rate • sticking fraction Sticking fraction = 0 for viscosity > log10 5.5 poise 0 to 1 for viscosity log10 5.5 -250 poise

Accumulation rate = Deposition rate – Slag flow rate Slag flow rate = density • average(Slag flow ratei )

Heat Flux- Volatiles and Char Combustion Gasifier Wall

Modeling Ash Behavior

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Partitioning Impurities Gas, liquid, solid Impurity Transport Diffusion, Thermophoresis Inertial Impaction Particle Sticking Coefficients Deposit Accumulation Surface sticking Coefficient Growth/Erosion Heat Transfer Thermal/mechancial properties Growth/shedding Impinging Flow Non-Impinging Flow Processes – chemical, physical properties and thermal mechanical behavior Algorithms to predict the size and composition distribution of the ash Fuel composition Size, composition, type, and abundance of mineral grains Abundance of organically associated elements Viscosity Calculations – Particle size fractions High temperature sintering processes Viscosity, surface tension, particle size, time Porosity/density Tensile Strength Thermal conductivity Low temperature (<800 ºC) Sulfide/halogen bonding Warn Gas Filter