Alex, Lizz y , Ogie, Matt, and Kathryn November 14, 20 1 1
1
Biofuels Subgroup Progress Report
Outline
• Overall Design of Biofuels Plant
• Switchgrass
• Gasification & T ar Removal
• Acid Gas Removal
• Fischer- T ropsch Reactor
• Distillation
• Refining
• Final Products and Carbon Sequestration
• Concluding Thoughts
2
H2O ( g )
Gasification
682 C
0.1 MPa
182 C
4.42 kg/s
12.5 MW
Output
55.7 kg/s
0.1 Mpa
Process Heat
Densified Feedstock 1000 kg/m^3
51.25 kg/s
682 C
39.8 MW
Sand Sand
Air 354 C
Combustion 917 C
Ash
H2O ( I )
Tar-free Syngas 682 C, 33.1 kg/s
Syngas
107 C, 33.1 kg/s
H2O ( g ) 28 MW
FTL
Heat
Light Gas
5.8 kg/s
Biodiesel
4.0 kg/s
Biogasoline
11.0 kg/s
Biojet
Pelletization 100 MPa
g g
Air
21.9 kg/s ” 260 C
2.4 MPa
CH3OH
CH3OH
Acid-gas Removal ( Amine, Lo-CAT ) 107 C
H2S
“0.02 kg/s
- 0 MPa
Distillation
0.1 MPa
350 C
Dry Storage Ambient T
0.1 MPa
H2O Vapor
Switchgrass
20% moisture
0.1 MPa
-40 C
0.1 MPa
Fe ( catalyst )
3.07 MPa
Syngas
250 C, 0.1 Mpa,
21.9 kg/s Y
Fischer Tropsch Process 245 C
1.5 Mpa
41 MW
GOS
CCS
CO2
11.2 kg/s
0.01 MPa
Saturated H2O ( g )
3.3 MPa H2
245 C
23.5 kg/s
S witchgrass
Hydrogen Process
Condensed H2O ( I ) 245 C
23.5 kg/s
3
H20 ( I ) EPA 36 C
H2O ( I )
888 kg/s
25 C
Natural Reservoir
4
H2O ( g )
Gasification
682 C
0.1 MPa
182 C
4.42 kg/s
12.5 MW
Output
55.7 kg/s
0.1 Mpa
Process Heat
Densified Feedstock 1000 kg/m^3
51.25 kg/s
682 C
39.8 MW
Sand Sand
Air 354 C
Combustion 917 C
Ash
H2O ( I )
Tar-free Syngas 682 C, 33.1 kg/s
Syngas
107 C, 33.1 kg/s
H2O ( g ) 28 MW
FTL
Heat
Light Gas
5.8 kg/s
Biodiesel
4.0 kg/s
Biogasoline
11.0 kg/s
Biojet
Air
21.9 kg/s ” 260 C
2.4 MPa
H2O Vapor
Pelletization 100 MPa
g g
Switchgrass
20% moisture
CH3OH
0.1 MPa
CH3OH
-40 C
0.1 MPa
Acid-gas Removal ( Amine, Lo-CAT ) 107 C
3.07 MPa
Syngas
250 C, 0.1 Mpa,
21.9 kg/s Y
H2S
“0.02 kg/s
- 0 MPa
GOS
CO2
11.2 kg/s
0.01 MPa
Distillation
0.1 MPa
350 C
CCS
Dry Storage Ambient T
0.1 MPa
Fe ( catalyst )
Fischer Tropsch Process 245 C
1.5 Mpa
41 MW
Saturated H2O ( g )
3.3 MPa H2
245 C
23.5 kg/s
S witchgrass
Hydrogen Process
Condensed H2O ( I ) 245 C
23.5 kg/s
5
H20 ( I ) EPA 36 C
H2O ( I )
888 kg/s
25 C
Natural Reservoir
Switchgrass I
Preparation
Outsource switchgrass ("SG") production and preparation to local farmers (possibly in T exas or Minnesota)
•
Densification
•
SG is originally 100 kg/m 3 , 51.77% of which is lignin and cellulose
•
• Densify at 137 MPa, 90 ° C with a screen size of 3.2 mm
• New density is around 1000 kg/m 3 , which is appropriate for injection into SI L V A gasification.
6
Switchgrass II
Densification Graph
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Switchgrass III
Preparation
• Moisture content: 20%
• Field drying
• W e will use all components of SG in pellets.
• 3500 tons/day
8
Courtesy of Oak Ridge National Laboratory.
9
G asification I
Silvagas Dual Fluidized Bed Cycle
10
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Gasification I
Silvagas Dual Fluidized Bed Cycle
11
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Gasification I
Silvagas Dual Fluidized Bed Cycle
12
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Gasification II
Inputs and Outputs
• Biomass Input: 41 kg/s dr y , 20% moisture = 51.25 kg/s total
• Steam Input: 182°C, 4.42 kg/s
• Air Input: 354°C, 4 kg/s
• T otal Mass Input: 55.67 kg/s
• T otal Syngas Output: 33.2 kg/s, 800°C
• T otal Flue Gas Output: 26.47 kg/s
13 Courtesy of Rentech, Inc. Used with permission.
Gasification III
Elemental Mass Balance
|
Major Element |
Input (kmol/s) |
Output in Syngas (kmol/s) |
Output in Flue Gas (kmol/s) |
|
T otal Carbon |
1.686 |
1.231 |
0.255 |
|
T otal Hydrogen |
4. 1 14 |
1.442 |
2.672 |
|
T otal Oxygen |
1.942 |
1.060 |
0.882 |
Estimated flow rates calculated using http://chippewa.gtsa v . g 1 4 atech.edu/outr each/workshop/pr esentations/gfarris.pdf & T win- Bed Gasification Concepts for Bio-SNG Pr oduction (Paisely)
Gasification IV
Composition of Syngas Output
|
Compound |
% by V olume |
Mass Flow (kg/s) |
|
CO |
47 |
18.459 |
|
H2 |
18 |
0.252 |
|
CO2 |
14.3 |
8.824 |
|
CH4 |
14.9 |
3.352 |
|
C2H4 |
4.7 |
1.849 |
|
C2H6 |
1.1 |
0.464 |
|
T otal |
100 |
33.200 |
Estimated flow rates calculated using http://chippewa.gtsa v . 1 g 5 atech.edu/outr each/workshop/pr esentations/gfarris.pdf & T win- Bed Gasification Concepts for Bio-SNG Pr oduction (Paisely)
H2O ( g )
Gasification
682 C
0.1 MPa
182 C
4.42 kg/s
12.5 MW
Output
55.7 kg/s
0.1 Mpa
Process Heat
Densified Feedstock 1000 kg/m^3
51.25 kg/s
682 C
39.8 MW
Sand Sand
Air 354 C
Combustion 917 C
Ash
H2O ( I )
Tar-free Syngas 682 C, 33.1 kg/s
Syngas
107 C, 33.1 kg/s
H2O ( g ) 28 MW
FTL
Heat
Light Gas
5.8 kg/s
Biodiesel
4.0 kg/s
Biogasoline
11.0 kg/s
Biojet
Pelletization 100 MPa
g g
Air
21.9 kg/s ” 260 C
2.4 MPa
Acid-gas Removal
H2S
Distillation
( Amine, Lo-CAT ) —'“0.02 kg/s
0.1 MPa
Dry Storage Ambient T
0.1 MPa
H2O Vapor
Switchgrass
20% moisture
CH3OH
0.1 MPa
CH3OH
-40 C
0.1 MPa
Fe ( catalyst )
107 C
3.07 MPa
Syngas
250 C, 0.1 Mpa,
21.9 kg/s Y
Fischer Tropsch Process 245 C
1.5 Mpa
41 MW
- 0 MPa
GOS
CO2
11.2 kg/s
0.01 MPa
Saturated H2O ( g )
3.3 MPa
245 C
23.5 kg/s
350 C
CCS
H2
S witchgrass
Hydrogen Process
Condensed H2O ( I ) 245 C
23.5 kg/s
16
H20 ( I ) EPA 36 C
H2O ( I )
888 kg/s
25 C
Natural Reservoir
Acid Gas Removal I
Overlap with Silvagas Process
17
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2. Cooling Syngas (682°C to 107°C)
3. W ater Scrubber (107°C, 1bar)
4. Compressor (1bar to 30.7bar)
5. Acid Gas Removal (Diethanolamin e HN(CH CH OH) )
2
2
2
6. LO-C A T (CO2, H2S Removal)
18
Acid Gas Removal II
Overall Process
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1. Particulate Removal (682°C, 1bar)
Acid Gas Removal III
Amine Plant
19
Courtesy of Plant Process Equipment, Inc. Used with permission.
Courtesy of Merichem Company. Used with permission.
• Removes all remaining CO
2
2
• Uses a dual chelated iron cat a 20 lyst - environmentally safe.
• Converts H S to an innocuous, elemental sulfur
Acid Gas Removal IV
LO-C A T process
21
Acid Gas Removal V
Composition of Input to F-T Reactor
|
Compound |
Mass Flow (kg/s) |
|
CO |
18.4 |
|
H2 |
0.34 |
|
CO2 |
0.00 |
|
CH4 |
3.71 |
|
C2H4 |
2.12 |
|
C2H6 |
0.31 |
|
T otal |
25.0 |
H2O ( g )
Gasification
682 C
0.1 MPa
182 C
4.42 kg/s
12.5 MW
Output
55.7 kg/s
0.1 Mpa
Process Heat
Densified Feedstock 1000 kg/m^3
51.25 kg/s
682 C
39.8 MW
Sand Sand
Air 354 C
Combustion 917 C
Ash
H2O ( I )
Tar-free Syngas 682 C, 33.1 kg/s
Syngas
107 C, 33.1 kg/s
H2O ( g ) 28 MW
FTL
Heat
Light Gas
5.8 kg/s
Biodiesel
4.0 kg/s
Biogasoline
11.0 kg/s
Biojet
Pelletization 100 MPa
g g
Air
21.9 kg/s ” 260 C
2.4 MPa
CH3OH
CH3OH
Acid-gas Removal ( Amine, Lo-CAT ) 107 C
H2S
“0.02 kg/s
- 0 MPa
Distillation
0.1 MPa
350 C
Dry Storage Ambient T
0.1 MPa
H2O Vapor
Switchgrass
20% moisture
0.1 MPa
-40 C
0.1 MPa
Fe ( catalyst )
3.07 MPa
Syngas
250 C, 0.1 Mpa,
21.9 kg/s
Fischer Tropsch Process —
245 C
1.5 Mpa
41 MW
GOS
CCS
CO2
11.2 kg/s
0.01 MPa
Saturated H2O ( g )
3.3 MPa H2
245 C
23.5 kg/s
S witchgrass
Hydrogen Process
Condensed H2O ( I ) 245 C
23.5 kg/s
22
H20 ( I ) EPA 36 C
H2O ( I )
888 kg/s
25 C
Natural Reservoir
Fischer T ropsch Reactor I
Slurry Phase Bubble Column Design
• Churn turbulent 2 phase flow
• Fe catalyst Catalyst activity:
Ru > Fe > Ni > Co > Rh
Courtesy of Elsevier, Inc., http://www.sciencedirect.com . Used with permission.
23
Fischer T ropsch Reactor I I
Reactions, Heat transfer
CO+2H2
-->
-(CH2)- + H2O+170kJ
H2O+CO
-->
CO2+H2
(water shift reaction)
Heat generated in FT reactor:
Q = 0.25kg/s*1mol/0.002kg*170kJ/mol = 21.8 MW
Intake water flow rate (using E P A limit of 1 1°C) m = Q/(C*( T a- T i)) = 470 kg/s
24
Fischer T ropsch Reactor III
Product Selectivity
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25
Fischer T ropsch Reactor IV
26
Reactor Outputs
|
Carbon Content |
Product Classification |
Mass Flow (kg/s) |
|
C1 - C5 |
Light Gas |
3.19 |
|
C5 - C12 |
Naphtha (Gasoline) |
9.70 |
|
C12 - C20 |
Distillate (Biodiesel) |
7.08 |
|
C20+ |
Heavy wax |
4.70 |
27
Distillation
|
Fraction |
Boiling Point (°C) |
|
Liquid Petroleum Gas |
< 40 |
|
Light Naptha |
30-90 |
|
Heavy Naptha |
90-200 |
|
Distillate |
200-300 |
|
Heavy W ax |
300-350 |
28
H2O ( g )
Gasification
682 C
0.1 MPa
182 C
4.42 kg/s
12.5 MW
Output
55.7 kg/s
0.1 Mpa
Process Heat
Densified Feedstock 1000 kg/m^3
51.25 kg/s
682 C
39.8 MW
Sand Sand
Air 354 C
Combustion 917 C
Ash
H2O ( I )
Tar-free Syngas 682 C, 33.1 kg/s
Syngas
107 C, 33.1 kg/s
H2O ( g ) 28 MW
FTL
Heat
Light Gas
5.8 kg/s
Biodiesel
4.0 kg/s
Biogasoline
11.0 kg/s
Biojet
r*
Pelletization 100 MPa
g g
Air
21.9 kg/s 260 C
2.4 MPa
CH3OH
CH3OH
Acid-gas Removal ( Amine, Lo-CAT ) 107 C
H2S
“0.02 kg/s
- 0 MPa
Distillation
0.1 MPa
350 C
Dry Storage Ambient T
0.1 MPa
H2O Vapor
Switchgrass
20% moisture
0.1 MPa
-40 C
0.1 MPa
Fe ( catalyst )
3.07 MPa
Syngas
250 C, 0.1 Mpa,
21.9 kg/s Y
Fischer Tropsch Process 245 C
1.5 Mpa
41 MW
GOS
CCS
CO2
11.2 kg/s
0.01 MPa
Saturated H2O ( g )
3.3 MPa H2
245 C
23.5 kg/s
S witchgrass
Hydrogen Process
Condensed H2O ( I ) 245 C
23.5 kg/s
29
H20 ( I ) EPA 36 C
H2O ( I )
888 kg/s
25 C
Natural Reservoir
Refining I
Composition of Distillation Output
30
• Better octane rating
5. Hydrocracking of n-paraffins to isoparaffins
31
Refining II
Purposes
1. Hydrogenation of olefins
2. Removal of oxygen-containing compounds
3. Desulfurization to < 20microgram/gram
4. Hydroisomerization
• Increases branched isomers
Refining III
Hydrogen Inputs
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32
Final Products
• Assuming 10 gal/tank, this amount of gasoline and diesel can fill about 53,000 cars/day
33
|
Product Classification |
Mass Flow (ton/day) |
Light Gas |
276 |
Diesel |
612 |
Gasoline |
838 |
T otal Gasoline + Diesel |
1450 |
Carbon Sequestration
GE CO2 management system
• CO2 sources: acid gas removal, distillation
Options: Sell, inject to underground storage, send to deep ocean dissolution
© General Electric Company. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse .
CO2 liquidifies at density 300kg/m^3
Compress to 200 bar with in- line integrally geared compressor and DDHF multistage barrel pump
34
Concluding Thoughts
• Research Continues
• Possible Electric Inputs
• Possible Heat Inputs and Outputs
• Hydrogen Inputs
• EES, Aspen modeling
• Questions
35
H2O ( g )
Gasification
682 C
0.1 MPa
182 C
4.42 kg/s
12.5 MW
Output
55.7 kg/s
0.1 Mpa
Process Heat
Densified Feedstock 1000 kg/m^3
51.25 kg/s
682 C
39.8 MW
Sand Sand
Air 354 C
Combustion 917 C
Ash
H2O ( I )
Tar-free Syngas 682 C, 33.1 kg/s
Syngas
107 C, 33.1 kg/s
H2O ( g ) 28 MW
FTL
Heat
Light Gas
5.8 kg/s
Biodiesel
4.0 kg/s
Biogasoline
11.0 kg/s
Biojet
Pelletization 100 MPa
g g
Air
21.9 kg/s ” 260 C
2.4 MPa
CH3OH
CH3OH
Acid-gas Removal ( Amine, Lo-CAT ) 107 C
H2S
“0.02 kg/s
- 0 MPa
Distillation
0.1 MPa
350 C
Dry Storage Ambient T
0.1 MPa
H2O Vapor
Switchgrass
20% moisture
0.1 MPa
-40 C
0.1 MPa
Fe ( catalyst )
3.07 MPa
Syngas
250 C, 0.1 Mpa,
21.9 kg/s Y
Fischer Tropsch Process 245 C
1.5 Mpa
41 MW
GOS
CCS
CO2
11.2 kg/s
0.01 MPa
Saturated H2O ( g )
3.3 MPa H2
245 C
23.5 kg/s
S witchgrass
Hydrogen Process
Condensed H2O ( I ) 245 C
23.5 kg/s
36
H20 ( I ) EPA 36 C
H2O ( I )
888 kg/s
25 C
Natural Reservoir
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22.033 / 22.33 Nuclear Systems Design Project
Fa ll 2011
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