Modelling of Gasification of Refuse-derived fuel (RDF) based on - - PowerPoint PPT Presentation
Modelling of Gasification of Refuse-derived fuel (RDF) based on laboratory experiments Juma Haydary Department of Chemical and Biochemical Engineering Institute of Chemical and Environmental Engineering Faculty of Chemical and Food Technology
Department of Chemical and Biochemical Engineering Institute of Chemical and Environmental Engineering Faculty of Chemical and Food Technology Slovak University of Technology in Bratislava, Slovakia
Cyprus 2016
Cyprus 2016
National center for research and application of renewable energy sources
Cyprus 2016
Cyprus 2016
Biodegradables Metals Inorganics Hazardous wastes
Component Material wi [kg/kg]
Paper White paper, recycled paper 0,6317 Foil LDPE, HDPE 0,1578 Plastics Rigid plastics, polystyrene, polyurethane 0,1910 Textile Polyamide, polyester, cotton , wool 0,0194
Cyprus 2016
Com.
ASH* C H N S O**
10 75.5 8.9 15.6 51.7 5.9 0.9 0.4 25.5
*moisture free basis **calculated to 100%
Cyprus 2016
Cyprus 2016
Cyprus 2016
Component Heating value [kJ/kg] Paper
13410
Foil
43860
Plastics
33570
Textile
19770
Mixed RDF
20810
Cyprus 2016
Tar content measurement
20 30 40 50 60 70 80 90 600 700 800 900 1000 1100 1200 Tar (mg/g RDF) Temperature (°C )
Assumptions:
considered inside the gasifier
concentration gradient exist inside the reactor
enough long to reach complete decomposition
considered in the product gases, i.e CO, CO2, H2, CH4 , H2O, NH3, H2S, N2 and Tar
5 7 1 2 2 2 3 4 2 2 6 4 2 8 3 9 2 10 1 1 1 1 c e b d c e b d
CH O N S x O x H O x CO x CO x H x CH x H O x NH x H S x CH O N S
Global material balance of RDF gasification
RDF TAR
2
0,5 C O CO
2 2
0,5 CO O CO
2 2 2
0,5 H O H O
4 2 2 2
2 2 CH O CO H O
2 2
C H O H CO
2
2 C CO CO
4 2 2
3 CH H O H CO
2 4
2 C H CH
2 2 2
CO H O CO H
Reactions:
i i i
i i a
x P P K
Equilibrium constant: RT G e K
r a 298 298
298 298 298
S T H G
r r r
,
298 298 i f i r
H H
298 298 i f i r
S S
298
( 298)
r r i pi
H H c T
298
ln 298
r r i pi
T S S c
2( ) RDF O air steam R gas ash C loss
Q – heat of reaction [J],
RDF
H
– enthalpy of RDF feed [J],
2( ) O air
H
– enthalpy of oxygen and air respectively [J],
steam
H
– enthalpy of water steam [J],
gas
H
– enthalpy of gas [J],
ash
H
– enthalpy of ash [J],
C
H – enthalpy of unreacted carbon [J],
loss
Q
– heat losses from the reactor [J]
R RDF i i c i i
IF, Tair =TRDF=Tref, then
RDF
H
=0,
2( ) O air
H
=0
RDF i i c i i loss ref i pi C pC ash pash steam steam
mRDF – mass flow of RDF feed [kg] ni – mole flow of component i in the products [kmol] wi – maas fraction of component i in the feed (paper, foil, plastics, textil Qi – lower heating value of component i in the feed (paper, foil, plastics, textile) [Jkg
i cH
mash – mass flow of ash [kg] mash – mass flow of remaining carbon [kg] msteam – mass flow of steam [kg]
pash
c
– specific heat capacity of ash [Jkg-1K-1]
pC
c
– specific heat capacity of remaining carbon [Jkg-1K-1]
psteam
c
– specific heat capacity of steam [Jkg-1K-1]
Observed parameters: Conversion of RDF Reactor Temperature Gas composition Content of pollutants (NH3, H2S, TAR) Variables: Oxygen (air) to RDF mass ratio Steam to RDF mass ratio
20 40 60 80 100 120 500 1000 1500 1 2 3 4 Conversion (%) Temperature (°C ) m(air)/m(RDF) Temperature Conversion 0,1 0,2 0,3 0,4 0,5 0,6 0,7 1 2 3 4 Mole fraction m(air)/m(RDF) H2 CO CH4 CO2 N2
0,0005 0,001 0,0015 0,002 0,0025 0,003 0,0035 0,01 0,02 0,03 0,04 0,05 0,06 0,07 0,08 0,09 0,1 1 2 3 4 H2S and NH3 mole fraction Tar mass fraction m(air)/m(RDF) Tar H2S NH3
50 100 150 1000 2000 3000 0,2 0,4 0,6 0,8 Conversion (%) Temperature (K) m(O2)/m(RDF) Temperature Conversion
0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,2 0,4 0,6 0,8 Mole fraction m(O2)/m(RDF) H2 CO CH4 CO2 N2
Mois 10 VM 75.5 FC 8.9 ASH 15.6 C 51.7 H 5.9 N 0.9 S 0.4 O 25.5
50 100 150 1000 2000 3000 0,2 0,4 0,6 0,8
Conversion (%) Temperature (K) m(O2)/m(RDF) Temperature Conversion
Mois 1.2 VM 80.22 FC 5.23 ASH 13.34 C 51.66 H 8.82 N 0.66 S 0.08 O 25.42
Sensitivity Results Curve R HC CO N XC H4 XC O2 XC O XH 2 TR K 0,20 0,25 0,30 0,35 0,40 0,45 0,50 0,55 0,60 0,65 0,70 0,75 0,80 0,85 0,90 0,95 1,00 1,05 1,10 1,15 1,20 1,25 8,0 8,5 9,0 9,5 10,0 10,5 11,0 11,5 12,0 12,5 13,0 13,5 14,0 14,5 15,0 15,5 16,0 16,5 17,0 17,5 18,0 18,5 19,0 19,5 20,0 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0,00 0,05 0,10 0,15 0,20 0,25 0,30 0,35 0,40 0,45 0,50 0,10 0,11 0,12 0,13 0,14 0,15 0,16 0,17 0,18 0,19 0,20 0,21 0,22 0,23 0,24 0,25 0,26 0,27 0,00 0,05 0,10 0,15 0,20 0,25 0,30 0,35 0,40 0,45 0,50 0,55 0,175 0,200 0,225 0,250 0,275 0,300 0,325 0,350 0,375 0,400 0,425 0,450 0,475 0,500 600 800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000 TR K XH2 XCO XCO2 XCH4 CON HC
0,1 0,2 0,3 0,4 0,5 0,1 0,2 0,3 0,4 0,5 Mole fraction m(Steam)/m(RDF) H2 CO CO2 8 8,5 9 9,5 10 1000 1050 1100 1150 1200 0,1 0,2 0,3 0,4 0,5 Heating Value (MJ/kg) Temperature (K) m(Steam)/m(RDF) Temperature Heating value
October 2015
gasification by air was reached at mair/mRDF=2,2. However, the gas heating value was 4,4 MJ/Nm3
with heating value around 10 MJ/Nm3 at mO2/mRDF=0,45
mair/mRDF
content a solid phase insoluble in isopropanol
increased, However, the content of CO, reactor temperature and gas heating vale decreased