COMBUSTION AND FUELS

AIR AND FUEL STAGING

IN PULVERIZED COAL

FIRED BOILERS

COMBUSTION AND FUELS

AIR STAGING IN PULVERIZED

COAL-FIRED BOILERS

COMBUSTION AND FUELS

AIR STAGING IN TANGENTIALLY FIRED BOILERS

over-

under-stoichiometric

axialstaging

ove

r-

radialstaging

un

der

-o

ver-

sto

ich

iom

etr

ic

ove

r-

ove

r-st

oic

hio

me

tric

combinedstaging

ub

der

-

λ<1

λ>1

COMBUSTION AND FUELS

Paliwo

OFA

λ>1

λ<1

Powietrze

Spalanie z niedomiarem O2

Spalanie z małym nadmiarem O2

OFA nozzles

Air

Fuel

Leancombustion

Richcombustion

AXIS AIR STAGING USING OFA NOZZLES

COMBUSTION AND FUELS

RADIAL AIR STAGING –

DIFFERENT RADIUS OF COAL AND AIR

FuelA

ir

Fuel

Fuel richzone

30% of air

30% of air

COMBUSTION AND FUELS

AIR STAGING SYSTEM LNCFS

core air pulverizedcoal

secondary air& oil burner

pulv. coal nozzle 1

pulv. coal nozzle 2

bottom air & oil burner

core air

OFA1 & oil burner

COMBUSTION AND FUELS

OFA NOZZLES IN OP 430 BOILER

COMBUSTION AND FUELS

OFA NOZZLES ON SIDE WALL OF OP 650 BOILER

COMBUSTION AND FUELS

FUEL STAGING IN

THE PF BOILERS

COMBUSTION AND FUELS

FUEL STAGING: Minimum Pollution (PM) METHOD

COMBUSTION AND FUELS

FUEL STAGING: system of pulverized coal supply

(Power Plant ŁAGISZA)

loose pulverized coal dense pulverized coal

COMBUSTION AND FUELS

Fuel staging in wall-fire boiler furnace

upper burners for dense pulverized coal stream

burners for loose pulverised coal stream

COMBUSTION AND FUELS

Combined low-NOx combustion methods I

Low-NOx boiler furnace with cyclone reburning of unburnt char,1 – natural gas, 2 – pulverized coal, 3 – air,

4 – flue gas recirculation, 5 – bottom ash disposal

COMBUSTION AND FUELS

Combined low-NOx combustion methods II

Low-NOx boiler furnace with fluidized reburning of unburnt char,1 – natural gas, 2 – pulverized coal, 3 – air,

4 – flue gas recirculation

COMBUSTION AND FUELS

FUEL STAGING:

reburning

Conventional combustion Combustion with reburning

Basic fuel - coal(75-90%)

Reburning fuel(10-25%)

Additional air

Zone of unburnt fuel combustion

λ>1

Reburning zone

λ<1

(reduction NOx to N2)

Basic burning zone

λ>1Coal(100%)

λ>1