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COMBUSTION AND FUELS

COMBUSTION OF

LIQUID FUELS

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COMBUSTION AND FUELS

PHASES OF LIQUID FUEL BURNING

Two phases of liquid fuel burning:a) phase of liquid evaporation,

b) phase of vapour burning.

Droplet of fuel

Cloud of vapour

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COMBUSTION AND FUELS

DOMINATING FACTORS OF OIL COMBUSTION

- liquid evaporation,

- mixing of vapour and oxidizer (air),

- chemical kinetics of combustion in gas phase.

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INFLUENCE OF GEOMETRY ON THE

COMBUSTION PATTERN

radiation

liquid fuelair

soot

diffusion

dropletof fuel

diffusionflame

air

droplets

+

air

evaporation

kineticflame

przewodzenie

ciepa

10-6

10-5

10-4

10-3

10-2

10-1

1 10 102

size [m]

heatconduction

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COMBUSTION AND FUELS

BURNING OF SINGLE OIL DROPLET

Diffusion model of single oil droplet combustion:a) flame geometry, b) temperature and fuel Cf/oxygen CO2 content

s

= kd02

oxidizer

products ofcombustion

droplet

vapour

vapouroxidizer

flame

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COMBUSTION AND FUELS

TIME OF BURNOUT OF A SINGLE OIL DROPLET

Time of burnuot s :

s = kd02

do initial diameter,

k coefficient.

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COMBUSTION AND FUELS

INFLUENCE OF FLOWFIELD ON THE

COMBUSTION PATTERN

1 2 3

a) Influence of natural convection, b) Influence of forced convection

(1 flow, 2 droplet, 3 recirculation zone)

flame

gas flow

fumes

droplet

oxygen

fuel

border of

heatedarea

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COMBUSTION AND FUELS

INFLUENCE OF INNER ROTATION OF LIQUID ON

THE COMBUSTION PATTERN

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COMBUSTION AND FUELS

Influence of droplet evaporation on the

combustion pattern

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COMBUSTION AND FUELS

BURNING OF A SINGLE DROPLET OF HEAVY OIL

Four phases of combustion:I time of induction ignition ended with ignition

of light fractions of oil,

II burning evaporation, cracking of heavyfractions of oil, formation of coke shell,

III micro explosion destruction of coke shall,

IV burnout of coke shall.

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COMBUSTION AND FUELS

HISTORY OF A SINGLE DROPLET BURNING (part 1)

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COMBUSTION AND FUELS

HISTORY OF A SINGLE DROPLET BURNING (part 2)

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COMBUSTION AND FUELS

TEMPERATURE HISTORY OF A SINGLE DROPLET BURNING

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COMBUSTION AND FUELS

COKE SHALE FORMATION AND RESIDUE

Coke shell

Shell formation

fuel droplet

coke shell

fragments of thebroken coke shell

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COMBUSTION AND FUELS

OIL-COKE MICROSCOPE PHOTO

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COMBUSTION AND FUELS

PATTERNS OF OIL DROPLETS BURNING IN FLAME

Group combustion

diffusion flame

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COMBUSTION AND FUELS

STRUCTURE OF DISPERSEDOIL FLAME

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COMBUSTION AND FUELS

STRUCTURE OF DISPERSED OIL FLAME:

1D - MODEL

1 2 3 4

oil droplets+air

flow dirrection

fumes

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COMBUSTION AND FUELS

STRUCTURE OF SPRAYED OIL FLAME

1 2 3 4 5

1 stream of sprayed fuel, 2 zone of evaporation, 3 zone of ignition,

4 zone of combustion of individual droplets, 5 boundary of flame

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COMBUSTION AND FUELS

STRUCTURE OF SWIRLED OIL FLAME

airrecirculation

zone

oil sprayingzone

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COMBUSTION AND FUELS

INFLUENCE OF SPRAY PATTERNON THE OIL-FLAME STRUCTURE

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COMBUSTION AND FUELS

TWO TYPES OF SPRAY PATTERN:A HOLLOW B SOLID

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HOLLOW CONE PLAME PATTERN

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FULL (SOLID) CONE PLAME PATTERN

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Structure

of swirledoil flame

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Structure

of swirledoil flame

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COMBUSTION AND FUELS

OIL BURNERS

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COMBUSTION AND FUELS

COMPACT OIL BURNERS

Compact oil burner has three main units:

oil atomisation,

aerodynamics,

control.

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COMBUSTION AND FUELS

SCHEME OF COMPACT OIL-BURNER

fan

ignitiontransformer

ignition

transformernozzle

ignition electrodes

head of burner

oil supply unit

oil filter

oil pump

oil pressure

regulator

cut off

valve

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COMBUSTION AND FUELS

EXAMPLE OF COMPACT OIL BURNER

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COMBUSTION AND FUELS

COMPACT OIL BURNER INSTALLED IN A BOILER

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COMBUSTION AND FUELS

HEAVY OIL BURNERS OF THE LANCE TYPE

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COMBUSTION AND FUELS

HEAVY OIL LANCE BURNER FOR BOILERS START UP

1 diffuser, 2 lance, 3 electric igniters air box

(P steam, M mazout, P1, P2 primary and secondary air)

LANCE OF MAZOUT BURNER

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LANCE OF MAZOUT BURNER

steam oil

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COMBUSTION AND FUELS

PARAMETERS OF MAZOUT AND STEAMIN START-UP BURNER

Parameter Unit Value

Mazout pressure MPa 0.4 0.6

Mazout temperature oC 115 130

Steam pressure MPa 0.8 1.0

Steam temperature oC 230

LOCATION OF MAZOUT BURNER IN SWIRL BURNER

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LOCATION OF MAZOUT BURNER IN SWIRL BURNER

MAZOUT BURNER IN BOILER FURNACE

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MAZOUT BURNER IN BOILER FURNACE

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COMBUSTION AND FUELS

SCANNER OF MAZOUT FLAME IN BOILER FURNACE

FIREYE InSight type 95

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COMBUSTION AND FUELS

LAMP OIL BURNER

wick