In s t i t u t e o f Th e r m a l Te c h n o l o g y
□
SlLESIAN UN1VERSITY OF TECH NOLOGY
Fa c u l t y o f En v i r o n m e n t a l
En g i n e e r i n g a n d En e r g y
IliSTU C l a u s t h a l
Clausthal University of Technology
Cl a u s t h a l Un i v e r s i t y o f Te c h n o l o g y
Fa c u l t y o f En e r g y a n d Ma n a g e m e n t
A
IEVB \ ^ _ InMttule of Energy Procesi Engineering and Fuel Technology
In s t i t u t e o f En e r g y Pr o c e s s En g i n e e r i n g a n d Fu e l T e c h n o l o g y
Ph.D. Thesis
lNVESTIGATION OF FlXED-BED
C
o m b u s t i o n
P
r o c e s s
i n
S
m a l l
S
c a l ę
B
o il e r s
Rafał Buczyński
T H I S THESIS WAS R EA L IZ ED IN T H E FR A M E O F T H E A G R E E M E N T B E T W E E N SlL ESIA N Un i v e r s i t y o f Te c h n o l o g y a n d Cl a u s t h a l Un i v e r s i t y o f Te c h n o l o g y
SuPERYISORS: PROF. ANDRZEJ SZLĘK, PROF. ROMAN W E B E R
Investigation of fixed-bed combustion process in
smali scalę boilers
Abstract of Ph.D. Thesis
Rafał Buczyński
T h is stud y is d e d ic a te d to e x am in in g o f c o m b u stio n pro cesses in a sm ali - scalę retort b o iler fired w ith sp ecially p rep a re d coal (or b io m ass pellets).
T he p resen t stu d y aim s at im p ro v in g th e c o m b u stio n process in su ch boilers. H erein, the search in g fo r d esig n im p ro v em en ts is b ased on scientific b ackg ro un d, w hich is a new a p p ro ach in th is b o ile r sector. In o rd er to fin d out the best desig n Solutions a C F D - b ased m ath em atical m odel has b een developed.
The fix ed -b ed su b -m o d el d ev elo p ed in th is thesis co n stitu tes the heart o f the overall C FD - b ased b o iler m o del. T he fix ed -b ed su b-m od el h as been v alid ated a g ain st m easu rem en ts o f tem p e ra tu rę an d gas co m p o sitio n o f a fix ed -b ed o f E K O R E T coal.
The n ew ly d ev e lo p e d fix ed -b ed su b -m o del has been im p lem en ted into the C F D F luent co de to sim u late a co m m ercial b o ile r unit. P erfecting the b o ile r d esig n resu ltin g in redu ced e m issio n o f p o llu tants, (C O and fly ash) can be achieved by rep o sitio n in g o f the deflector, red irectio n o f air supply p ath s into th e c o m b u stio n ch am bers as w ell as reshaping o f the co m b u stio n cham ber.
Fin ally , an o p tim iz e d b o ile r d esig n has b een p ro po sed, w h ic h features the circular c o m b u stio n ch a m b e r and co m b u stio n air sw irling. T he decrease o f C O em issio n by m ore than 90\% is fo re se en at e x cess air ratio o f 2.0.
