experimental investigation of single-particle gasification
TRANSCRIPT
14th of June 2016, Cologne, Germany
F. Küster1, R. Ackermann2, S. Guhl1, B. Meyer1
1IEC, TU Bergakademie Freiberg, Germany; 2IAP, Friedrich-Schiller-Universität Jena, Germany
Experimental investigation of single-particle gasification
Experimental investigation of single-particle gasification
2
Outline
8th International Freiberg Conference, 12 – 16 June 2016
1. Background and Motivation
2. The HITECOM Reactor
3. Development of a single particle holder
• Requirements / overview particle holder
• Overview adhesive-fixation
• Integration in HITECOM-System
4. Results and und Discussion
• Feedstock characterization
• Investigation of single-particle reactions
• Determination of kinetic parameters
• Further results
5. Conclusion / Outlook
Experimental investigation of single-particle gasification
3
Motivation
• Spatial and time resolved characterization of thermochemical conversion of single particles in directed
flow at T < 1400 °C and up to 40 bar for fundamental research and advanced CFD validation
• Temperature map on the particle surface
• Temperature- and concentration profiles in the boundary layer around particles
Challenges:
• High pressure
• High temperature
• reactive gases
• Integration of optical ports
• single-particle gasification
Friedrich-Schiller-Universität Jena
Institute of Applied Physics
TU Bergakademie Freiberg
Institute of Energy Process
Engineering and Chemical
Engineering
METAZIK
LIF, RAMAN,
Thermography
The HITECOM Reactor
5
Overview
8th International Freiberg Conference, 12 – 16 June 2016
Specifications:
• Magnetic suspension balance
• Ceramic flow tube
• TMAX=1400 °C, pMAX= 40 bar
• Four optical ports
(perpendicular to the flow
direction; material: sapphire)
• Feed gases: CO, CO2, H2Og, H2,
O2, N2 and Ar
(1 – 200 l/min)
Challenging Task:
Integration of particle holder
Single particle holder
7
Demands for single particle holder
8th International Freiberg Conference, 12 – 16 June 2016
Fixation various particles (1.0 – 4.0 mm)
Temperature resistance (up to 1400 °C)
Rigidity (no natural oscillation)
Tolerance of shrinking particles
good fixation in direct flow
Minimal flow field distortion
Compatibility with magnetic suspension balance / reactor
Development of new concepts for the fixation of single-particles in direct flow
Combination with magnetic suspension balance
Modification of the HITECOM-System
Single particle holder
8
Overview
8th International Freiberg Conference, 12 – 16 June 2016
Wire-fixation Ceramic-fixation Adhesive-fixation
Task: Realization of a vibration-free particle holder tolerant
against particle-shrinkage
Traditional particle holder with wire basket
Disadvantages:
• Disruption of the flow field
• Sensitive against direct flow (vibration)
• Problematic measurement of the boundary layer
• Not suitable for single particles
Classical:
Alternatives:
Single particle holder
9
Particle holder type C – Adhesive-fixation
8th International Freiberg Conference, 12 – 16 June 2016
Type C.1 Type C.2
Advantages:
• suitable for direct flow
• vibration-free
• excellent reusability / easy of assembly
• temperature resistant
• low error rate
hanging standing
Single particle holder
10
Particle holder type C – Adhesive-fixation (C.1)
8th International Freiberg Conference, 12 – 16 June 2016
Lignite I (T=900 °C, p=1.0 bar CO2)
Single particle holder
11
Particle holder type C – Adhesive-fixation (C.2)
8th International Freiberg Conference, 12 – 16 June 2016
Lignite I (T=900 °C, p=1.0 bar CO2)
Results and discussion
13
Feedstock characterization
8th International Freiberg Conference, 12 – 16 June 2016
• Characterization of single-particles of three different feedstocks (lignite and hard coal)
• Characterization of a synthetic mixture of several single-particles of the three feedstocks
(traditional methods)
• Ultimate analysis (DIN 517 24/32)
• Proximate analysis (DIN 517 18/19/20)
• particle shape (CAMSIZER)
• Reactivity (reference thermobalance, 1bar CO2, 800-1000°C)
• Challenges:
• Hypothesis: „each particle is different“ (Influence of feedstock)
• Non-destructive analysis methods (difficult / impossible)
• Ultimate- and proximate analysis of the same particle: impossible
• Ultimate analysis according to DIN
• Proximate analysis in accordance with DIN
Results and discussion
14
Feedstock characterization – single-particles
20
30
40
50
60
70
80
90
100
Car
bo
n c
on
ten
t[w
t.-%
]
Hard coal (x=1.6-2.0 mm)
20
30
40
50
60
70
80
90
100
Car
bo
n c
on
ten
t[w
t.-%
]Central German lignite (lignite I; x=0.5-3.0 mm)
1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9
0
10
20
30
40
50
60
70
80
w A (wf) FB (wf) CFIX (wf)
wt.
-%
Central German lignite (lignite I; x=0.5-3.0 mm)
BK2820_4,85
BK2820_4,86
BK2820_4,88
MAX
Min
0
10
20
30
40
50
60
w A (wf) FB (wf) CFIX (wf)
wt.
-%
Hard coal (x=1.6-2.0 mm)
SK3010_5,60
SK3010_5,62
SK3010_5,64
MAX
Min
moisture ash (wf) volatile (wf) fixed carbon
(wf)
moisture ash (wf) volatile (wf) fixed carbon
(wf)
Ultimate
analysis
Proximate
analysis
Results and discussion – feedstock characterization
15
Reactivity – single-particles
0
2
4
6
8
10
12
14
16
18
BK3037 BK2820 SK3010
Rea
cti
vit
y i
nd
ex
R [
1/h
]
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
SK3010
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
0.0035
0.0040
0.0045
BK3037 BK2820 SK3010
Rea
cti
on
rate
r [
1/s
]
0.00000
0.00003
0.00005
0.00008
0.00010
0.00013
0.00015
0.00018
0.00020
SK3010
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
0.0035
0.0040
0.0045
0% 20% 40% 60% 80% 100%
Rea
cti
on
rate
r
[1/s
]
Carbon conversion Xc
Lignite I (7.52<m<10.36 mg)
10,36 7,52 8,25 8,33 8,35 8,76 9,01 9,06
Reaction rate r:
𝑟 =1
𝑚𝐶,0∙𝑑𝑚𝐶
𝑑𝑡=𝑑𝑋𝐶𝑑𝑡
reactivity index RS (Carbon conversion Xc=50%):
𝑅𝑆 0.5 =0.5
𝑡1/2
Influence of feedstock
Carbon conversion Xc=50%
Lignite I Lignite II Hard coal Lignite I Lignite II Hard coal
Results and discussion – single-particle reactions
16
Single-particle reactions in HITECOM reactor (I)
8th International Freiberg Conference, 12 – 16 June 2016
0
1
2
3
4
0 500 1000 1500 2000 2500 3000 3500 4000
Par
ticl
em
ass
m [
mg]
time [s]
0
1
2
3
4
5
0 100 200 300 400 500 600 700
Par
ticl
em
ass
m [
mg]
time [s]
Lignite I (T=1000 °C, p=1.0 bar CO2) Hard coal (T=1000 °C, p=1.0 bar CO2)
Results and discussion – single-particle reactions
17
Single-particle reactions in HITECOM reactor (II)
8th International Freiberg Conference, 12 – 16 June 2016
0
5
10
15
20
25
0 100 200 300 400 500 600 700 800
Pa
rtic
lem
as
sm
[m
g]
time [s]
Lignite II (T=1000 °C, p=1.0 bar CO2)
Results and discussion – single-particle reactions
18
Single-particle reactions in HITECOM reactor (II)
8th International Freiberg Conference, 12 – 16 June 2016
0
5
10
15
20
25
0 100 200 300 400 500 600 700 800
Pa
rtic
lem
as
sm
[m
g]
time [s]
IEC-Nr.: 2820 (T=1000 °C, p=1.0 bar)
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 0.2 0.4 0.6 0.8 1
Carb
on
co
nve
rsio
nX
c
time τ [-]
• Performing single-particle gasification
is possible
• Determination of kinetic parameters
0.000
0.001
0.001
0.002
0.002
0.003
0.003
0.004
0% 20% 40% 60% 80% 100%
Re
acti
on
rat
e r
[1
/s]
Carbon conversion Xc
r(BK2820)0.000
0.001
0.001
0.002
0.002
0.003
0.003
0.004
0% 20% 40% 60% 80% 100%
Re
acti
on
rat
e r
[1
/s]
Carbon conversion Xc
r(BK2820) r(SCM)
Results and discussion – single-particle reactions
19
Validating the HITECOM results – experimental design
8th International Freiberg Conference, 12 – 16 June 2016
IEC-Nr.: 2820 (T=1000 °C, p=1.0 bar)• Preliminary tests using reference thermobalance
• Characterization of single-particles (lignite and hard coal)
• Characterization of powdered samples (homogeneous)
• Ceramic crucible (particle container, 10µl)
• Experimental conditions:• Temperature range: 800-1000 °C (50K-steps)
• Pressure: 1bar CO2
• Experiments in HITECOM-reactor
• Characterization of single-particles (lignite and hard coal)
• Adhesive-fixation (hanging)
• Experimental conditions:• Temperature range: 800-1000°C (50K-steps)
• Pressure: 1bar CO2
• Comparison of the results
-7.0
-6.5
-6.0
-5.5
-5.0
-4.5
-4.0
0.78 0.83 0.88 0.93
ln(k
) [1
/s]
1/T [103 K]
Results and discussion – single-particle reactions
20
Validating the HITECOM results – determination of kinetic parameters
-7.0
-6.5
-6.0
-5.5
-5.0
-4.5
-4.0
0.78 0.83 0.88 0.93
ln(k
) [1
/s]
1/T [103 K]
BK3037_0,5-3,0_xmg ( 4 ) HITECOM
• Determination of kinetic parameters
successful (Arrhenius plot)
• Validation with data from the reference
thermobalance successful
• Influence of the feedstock confirmed Possible solution: synthetic particles
-11.5
-10.5
-9.5
-8.5
-7.5
-6.5
-5.5
-4.5
0.78 0.83 0.88 0.93
ln (
k)
[1/s
]
1/T [103 K]
-11.5
-10.5
-9.5
-8.5
-7.5
-6.5
-5.5
-4.5
0.78 0.83 0.88 0.93
ln (
k)
[1/s
]
1/T [103 K]
SK3010_1,6-2,0_xmg ( 3 ) HITECOM
Hard coal (XC=0.5, p=1.0 bar CO2)
Temperature range:
800-1000 °C
Lignite I (XC=0.5, p=1.0 bar CO2)
Results and discussion – single-particle reactions
21
Further results – synthetic particles
8th International Freiberg Conference, 12 – 16 June 2016
• Idea: Minimization the influence of the feedstock with „ideal“ particles
Known and homogeneous composition
Known (ideal) particle shape
Known reactivity
Known and well defined properties
comparative measurements
0
1
2
3
4
5
6
0 100 200 300 400 500
Part
icle
mass m
[m
g]
Time [s]
Synthetic particle (T=1000 °C, p=1.0 bar CO2)
Results and discussion – single-particle reactions
22
Further results – thermal camera
8th International Freiberg Conference, 12 – 16 June 2016
• Task: Integration of the thermal camera in the HITECOM reactor
• Calibration of the thermal camera under real conditions
• Visual observation of single-particles during gasification
Temperature map on the particle surface under gasification conditions
Compare with simulation
Lignite I (T=1050 °C, p=1.0 bar CO2)
Experimental investigation of single-particle gasification
24
Conclusion
8th International Freiberg Conference, 12 – 16 June 2016
• Development, construction and commissioning of the HITECOM-Reactor finished• Software and hardware improvements
• Integration of particle holder into the TG• Further development of the particle holder / adhesive composition
• Combination of the particle holder with TG interface
• Performing single-particle gasification is possible• Adjustment to models is possible
• Determination of kinetic parameters• Validation with data from the reference thermobalance successful
• Influence of feedstock not negligible!• the differences in reactivity between particles from the hard coal are larger than the
differences between particles of two central German brown coals
• „each particle is different“
• “Avoid” the influence of the feedstock• Possible solution: synthetic particles
Experimental investigation of single-particle gasification
25
Outlook
8th International Freiberg Conference, 12 – 16 June 2016
• Expansion of the experimental design (CO2-gasification)
• Test other single-particle holder (e.g. ceramic-fixation)
• Variation of the flow conditions
• Variation of the pressure conditions (partial pressure / total pressure)
Expanding applicability of kinetic parameters
• Investigation of the influence of the adhesive
• Water steam gasification
T=1000 °C, p=1.0 bar