Solvent Extraction
AOCS Annual Meeting & ExpoOrlando, FL
May 2017
Oilseedmicrostructure
Oilseed microstructure
Typical Soybean Flake
Lets zoom in fora closer look
Oilseed microstructure
Oilseed Flake Cell Structure
0.38 mm Approx. 15 cells thick
Oilseed microstructure
Soybean Flake Cell Structure
0.38 mm
Lets zoom in further to view a single cell
Oilseed microstructure
25 μm
75 μm
Typical Soybean Cell
Oilseed microstructure
Protein Bodies
Cell Wall
Carbohydrates, Ash, etc.
Oil Bodies (0.2-0.5 μm diameter)
Typical Soybean Cell
Oilseed microstructure
Actual Soybean Cell
Protein Bodies
Cell Wall
Carbohydrates, Ash, etc.
Oil Bodies(0.2-0.5 μm diameter)
Yaklich/Murphy, USDA-ARS
Oilseed microstructure
Typical Oil BodyHuang, University of California
Triglycerides(blue)
Phospholipids(red)
Oleosin(yellow)
.2-.5 μm
Solvent ExtractionProcess
Seed Preparation Impact
The seed preparation process determines the portion of the cells whose walls are ruptured.
FLAKING – ruptures a portion of the cell walls
EXPANDING – ruptures a significant portion of the cell walls
PREPRESSING – ruptures a significant portion of the cell walls
Solvent Extraction Process
For cells with ruptured walls, oil is extracted quickly via:
LEACHING / WASHING
DIFFUSION / DIALYSIS
For cells with walls intact, oil is extracted slowly via:
Solvent Extraction Parameters
1. EXTRACTION CONTACT TIME2. NUMBER OF EXTRACTION STAGES 3. PARTICLE THICKNESS4. MISCELLA FLUX RATE 5. SURFACE MOISTURE6. TEMPERATURE7. SOLVENT RETENTION
Solvent Extraction Parameters
Extraction contact time is the total time in which miscella immerses the material while descending down through the material layer.
1. Extraction Contact Time
Solvent Extraction Parameters
Increasing the number of countercurrent extraction stages that approach equilibrium, shortens the total extraction time required.
It is important that each stage approaches equilibrium, and does not mix with adjacent stages to be effective.
Most commercial extractors have 6-12 extraction stages.
2. Number of Extraction Stages
Solvent Extraction Parameters
Particle thickness determines the time required for the miscella in the cells to approach equilibrium with the surrounding miscella at each
extraction stage.
Seed type & material preparation have a significant impact:Soybean Expandates: 4 minutes/stage
Rapeseed Cake: 8 minutes/stage0.38 mm Soybean Flakes: 5 minutes/stage0.30 mm Soybean Flakes: 4 minutes/stage
The material preparation choice significantly impacts operating cost.
3. Particle Thickness
Solvent Extraction Parameters
Miscella flux rate is the rate which miscella descends down through the material layer.
Critical in extractor design to minimize extraction stage mixing.
Material preparation has a big impact on the miscella flux rate:
Soybean Expandates: 41 m3/h/m2 or 1.4 m/min down through expandatesRapeseed Cake: 25 m3/h/m2 or 0.8 m/min down through cake0.38 mm Soybean Flakes: 19.5 m3/h/m2 or 0.6 m/min down through flakes0.30 mm Soybean Flakes: 12.5 m3/h/m2 or 0.4 m/min down through flakes
4. Miscella Flux Rate
Solvent Extraction Parameters
A coating of surface moisture on the particles in the extractor impedes the ability for miscella to penetrate the coated
particles, preventing proper oil extraction.
Excess moisture in the air surrounding the flakes, expandates or cake conveyed to the extractor can condense on the surface of
the particles, causing a coating of surface moisture.
Proper preparation aspiration and conveyor insulation is critical for good extraction results.
5. Surface Moisture
Solvent Extraction Parameters
The higher the extractor operating temperature, the faster the miscella diffuses through cell walls, and the faster the miscella in the cells approaches
equilibrium with the surrounding miscella.
When balancing extraction efficiency with safety and environmental concerns,
the extractor should ideally be operated just under the azeotropic solvent boiling temperature of 61-62°C.
6. Temperature
Solvent Extraction Parameters
Solvent retention is the amount of weak miscellaleaving the extractor in the extracted solids.
The dripping time, material layer height, miscella flux rate, and supporting screen open area
all impact solvent retention.
Solvent retention is in the range of 26-30% in adequately sized extractors.
7. Solvent Retention
Solvent Extraction Parameters
1. EXTRACTION CONTACT TIME2. NUMBER OF EXTRACTION STAGES 3. PARTICLE THICKNESS4. MISCELLA FLUX RATE 5. SURFACE MOISTURE6. TEMPERATURE7. SOLVENT RETENTION
Major Solvent ExtractorDesigns
Major Solvent Extractor Designs
Chain Conveyor Type
Crown Model III Extractor
Major Solvent Extractor Designs
Belt Conveyor Type
Desmet Ballestra LM™ Extractor
Major Solvent Extractor Designs
Rotary Compartment Type
Desmet Ballestra Reflex® Extractor
Major Solvent Extractor Designs
Linear Compartment Type
Lurgi Extractor
Major Solvent Extractor Designs
All of these major extractor designs can achieve similar oilextraction efficiency when adequately sized, fed a properly prepared product, and they are properly operated OPEX, CAPEX and maintenance requirements (reliability)
are the differentiating factors
Performance
MealDesolventizing
DT Unit Processes
Predesolventizing
Desolventizing
Toasting & Stripping
Steam Drying
DT Unit Processes
Predesolventizing
Purpose is to remove a minority of the solvent usingindirect steam heat to reducelive steam condensed into themeal and thereby save DC steam 10-20% of solvent removed 5766°C meal temperature 12% typical meal moisture
DT Unit Processes
Purpose is to remove the majority of the solvent using live steam 80-90% of solvent removedMostly direct steam latent heat Some added indirect steam heat 6699°C meal temperature 1220% meal moisture
Desolventizing
DT Unit Processes
Toasting & Stripping
Remove final traces of hexane Deactivate anti-nutritional factors Direct Steam Specific Heat Indirect Steam Heat 99-108°C Meal Temperature 2019% Meal Moisture 20-25 minutes (soybean)
DT Unit Processes
Steam Drying
Purpose is to both dry the meal to save DC steam, and to enable low pressure water vapor heat to be recovered in extraction Half of drying heat is from meal Half of drying heat is from trayWater vapor captured via
steam ejector for heat recovery
MealDrying & Cooling
DC Unit Processes
Meal drying
Meal cooling
DC Unit Processes
18-21% meal moisture in 102°C meal temperature in 13% typical meal
moisture out 63°C typical meal
temperature out 600 mm typical meal levelsMechanical gate level
control
Meal Drying
DC Unit Processes
13% meal moisture in 63°C meal temperature in 12.3% typical meal
moisture out 38°C typical meal
temperature out
Meal Cooling
Miscella Distillation
Miscella Distillation
Miscella Distillation
Approximately 94% of the solvent is evaporated in this process step using waste heat from the DT vent
Miscella composition entering is 20-30% oil & 70-80% solvent
Miscella composition exiting is 80-90% oil & 10-20% solvent
Critical heat recovery device
First Stage Solvent Evaporation
Miscella Distillation
Second Stage Solvent Evaporation
Approximately 5% of the solvent is evaporated in this process step using fresh steamMiscella composition entering
is 80-90% oil & 10-20% solventMiscella composition exiting
is 96-97% oil & 3-4% solvent
2 Pr
ehea
ting
pass
es
Evap
orat
ion
Miscella Distillation
Live Stream Stripping
Approximately 1% of the solvent is evaporated in this process step using fresh steamMiscella composition entering
is 96-97% oil & 3-4% solventMiscella composition exiting
is 99.995% oil & 0.005% solvent
Solvent Recovery
Atmospheric Vapor Condensation
Separation Tank
Atmospheric Condenser
Miscella Tank
First Stage Evaporator
MOS
Solvent Recovery
Extractor
DT
Vacuum Vapor CondensationO
il Stripper
Vacuum Condenser
Second Stage Evap.
First Stage Evaporator
Oil Dryer
Solvent Recovery
M.O
. StripperVacuum
Pre-Condenser
Solvent Recovery
Solvent / Water Separation
Vacuum Condenser Vacuum Pre-Condenser
First Stage Evaporator
Atmospheric Condenser
Solvent/Water Separator
solventwater effluent
Solvent Heating
Solvent Recovery
Solvent Heater(steam
heat)
Vacuum Precondenser
(waste stripper heat)
To Extractor
60°C
38°C
60°C
Condensate Preheater(condensate flash heat)
54°C
solvent
~99.95% solventis recovered andrecirculated tothe extractor
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Final Vent Cooler
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Solvent Vapor Absorber
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Oil/Oil Heat Exchanger
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Mineral Oil Heater
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Mineral Oil Stripper
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Mineral Oil Cooler
Mineral Oil System
From Sol vent RecoveryItem 20B/C
SOLVENT VAPORABSORBER
120
To Solvent RecoveryItem 32/34
To Solvent RecoveryItem 23A
Steam FromSteam And Condensate
To Steam And CondensateItem 46ATM
CWR
Steam FromSteam And Condensate
Vent T oA tmosphere
ATM
EXHAUSTVENT FAN
136
MINERAL OILCOOLER
181B
MINERAL OIL/MINERAL OIL
HEAT EXCHANGER
181A
MINERAL OILHEATER
121
MINERAL OILSTRIPPER
122
FINAL VENTCOOLER
20D
P122
TI20D
PI20D
TI20D
TT120
AT120
FA120
P120
PIP120
TIP120
LT120
LCVP120
PT120
PI136
PI120
FCV120
TI181B
TI181B
PI181B
TI181B
TI181A
PIP122
TIP122
LS122
PI122
FG122
PI121
TT121
ATM
TI121
PI122
TI122
TCV121
XV121
SC136
ATM
ATM
CWS
PI20D
TT120
TI20D
FT120
PSV122
PSV181B
FG20D
FT120
PSV181A
Solvent Vapor Absorber
Mineral Oil System
Thank you!
Tim KemperGlobal Operations Director,OFO Division
AOCS Annual Meeting & ExpoOrlando, FL
May 2017
Solvent ExtractionOilseed�microstructureOilseed microstructureOilseed microstructureOilseed microstructureOilseed microstructureOilseed microstructureOilseed microstructureOilseed microstructureSolvent Extraction�ProcessSeed Preparation ImpactSolvent Extraction ProcessSolvent Extraction ParametersSolvent Extraction ParametersSolvent Extraction ParametersSolvent Extraction ParametersSolvent Extraction ParametersSolvent Extraction ParametersSolvent Extraction ParametersSolvent Extraction ParametersSolvent Extraction ParametersMajor Solvent Extractor�DesignsMajor Solvent Extractor DesignsMajor Solvent Extractor DesignsMajor Solvent Extractor DesignsMajor Solvent Extractor DesignsMajor Solvent Extractor DesignsMeal �DesolventizingDT Unit ProcessesDT Unit ProcessesDT Unit ProcessesDT Unit ProcessesDT Unit ProcessesMeal �Drying & CoolingDC Unit ProcessesDC Unit ProcessesDC Unit ProcessesMiscella DistillationMiscella DistillationMiscella DistillationMiscella DistillationMiscella DistillationSolvent RecoverySolvent RecoverySolvent RecoverySolvent RecoverySolvent RecoveryMineral Oil SystemMineral Oil SystemMineral Oil SystemMineral Oil SystemMineral Oil SystemMineral Oil SystemMineral Oil SystemMineral Oil SystemMineral Oil SystemThank you!