Post on 14-Oct-2020
transcript
Pressure drop
Modelling of the carbonator reactor of the 20 MWth unit by means of a 3D Eulerian CFD model validated with the operating conditions and experimental data of the pilot-scale 1 MWth carbonator unit
Numerous house-built models, representing difficult physical mechanisms, have been developed and integrated in the Ansys/Fluent Platform
Introduction
- Cases tested: a) Base Case and b) SbS (Sorbent Staging design) new-design concept - Implementation of advanced Energy-Minimization Multi-Scale (EMMS) scheme
- Implementation of reaction rate by Hawthorne et al., with Xmax=0.1
Numerical Method + Cases
Zeneli Myrto, Nikolopoulos Aristeidis, Nikolopoulos Nikos, Grammelis Panagiotis, Kakaras Emmanouil
Scale-up of Calcium Carbonate Looping Technology for efficient CO2 Capture from Power and Industrial Plants
SCARLET Design of CCL reactor system components for 20 MWth pilot plant
Figure 2. a) 3D 20 MWth geometry and b) 3D numerical grid with zoom areas of the carbonator riser
Temperature Pressure (Outlet) Inventory Domain Cells (hexahedral)
Dcell/Dp Particle diameter (Geldart A)
923 K 1 bar 2270 kg 319385 500.73 108.433 μm
CO2/Volume fraction profiles
Table 1. Boundary/Operating conditions
Figure 5. Contours of the time-averaged mean YCO2 at X=0, for taver= 100 s for the a) Base case and b) SbS concept
Figure 4. Time-averaged mean static pressure along the reactor axis
Figure 3. CERTH/CPERI EMMS map implemented in the 20 MWth carbonator unit
CO2 Capture Efficiency
Contact Myrto Zeneli CERTH/CPERI http://www.cperi.certh.gr/ Email: zeneli@certh.gr Phone: +302111069597 www.project-scarlet.eu
1: Distributor 2: LS_recirculation (from carbonator) 3: LS_from_calciner (from calciner) 4: Stage 1 5: Stage 2 6: Outlet
6
1
2 3 4 5
20 m
a b
]/1[),,22
(32)max(010 seqCOCCOCcarbXX
e
Ssk
dtcarbdX
−−−
=
References 1. Zeneli, M., et al., Application of an advanced coupled EMMS-TFM model to a pilot scale CFB carbonator. Chemical Engineering
Science, 2015. 138: p. 482-498. 2. Hawthorne, C., et al. Design of a dual fluidized bed system for the post-combustion removal of CO using CaO. Part I. CFB
carbonator model. in 9th International Conference on Circulating Fluidized Beds. 2008. Hamburg,Germany. 3. Nikolopoulos, A., et al. PSD incorporation in full - loop CFD modeling of CFBs in 21st international conference on Fluidized Bed
Combustion. 2012. Naples, Italy. 4. Nikolopoulos, A., et al., An advanced EMMS scheme for the prediction of drag coefficient under a 1.2 MWth CFBC isothermal
flow—Part II: Numerical implementation. Chemical Engineering Science, 2010. 65(13): p. 4089-4099.
Case Studied Capture Efficiency Standard design (20 MWth) 86.95 % SbS design (20 MWth) 87.13 % Standard design (1 MWth) 87.03 % SbS design (1 MWth) 89.64 %
BC type Parameters Units Values Distributor Mass flow Inlet ṁgas kg·s-1 4.44125 XO2 /XCO2 kmol·kmol-1 0.06659/0.10573 XH2O /XN2 kmol·kmol-1 0.11395/0.71373 LS_recirculation Mass flow Inlet ṁgas kg·s-1 0.004680556 XH2O kmol·kmol-1 1 LS_from_calciner Mass flow Inlet ṁgas/ ṁsolid kg·s-1 0.00354167/12.6 XH2O kmol·kmol-1 1 XCaSO4/Xcoal[ash] /XCaO kmol·kmol-1 0.01514/0.120709/0.8642 Stage 2 Mass flow Inlet ṁgas/ ṁsolid kg·s-1 0/ 1.26 (10 % of the
regenerated sorbent) XCaSO4/Xcoal[ash] /XCaO kmol·kmol-1 0.01514/0.120709/0.8642 Walls Gas phase: No slip condition Solid phase: φ=0.01
Table 2. CO2 capture efficiency (1 MW and 20 MW unit)
X=0 (up to height 8m)
X=0 Y=0 Y=0
LS_recirculation
LS_from_calciner
Stage 2
LS_recirculation
LS_from_calciner
Stage 2
EMMS
YuWend F
FH &=),( &,, KwaukLiclSubbaraoclcl ddMind =
gUUNgUUUd
dmfsmfmfgssst
mfsmfmfspcl ))1/(()/(
))]1/(()1/([ max2 εερρρ
εεε−+−−
−+−−=pvcl d
ffDd +−
= 21
1 )1
(
Figure 1. Mean static pressure along the riser axis (1 MWth Carbonator)
Figure 6. Contours of the time-averaged mean solids volume fraction at X=0 and Y=0 for the a) Base case and b) SbS concepts
Mass Flow rate (at the exit): Base Case: ≈ -150 kg/s SbS Case: ≈ -150 kg/s
6 m