Download Recovery of Residual Oil

Recovery of Residual Oil
Wim Mulder, Paulien Harmsen, Patrick Carre
Sustoil, Foggia 24 April 2009
Introduction
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Residual oil recovery dependent on oil content of starting
material and cake
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Oil recovery methods
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Rapeseed and sunflower: 40-50% oil
Olive: 20% oil and 50% water
Methods nowadays used
Potential new techniques
Scientific literature
Rapeseed and sunflower
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Flaking, pretreatment, pressing, solvent extraction
Oil recovery
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Flaking
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Increase surface/improve heat transfer
Improve oil availability
Hydrolysis can occur (enzymes)
Pretreatment
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Pressing not efficient without heat treatment
Cooking
• Oil in cake by cold pressing rapeseed: 13.3%
• Oil in cake after intense cooking of rapeseed: 7.7%
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Cooking decreases feed value due to protein denaturation
Removal of water increases oil yield
Microwave
Pulsed electric field
Enzymatic pretreatment
Oil recovery; pressing and related processes
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Screw pressing
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Continuous screw presses (expellers)
Cold pressing of rapeseed and sunflower not possible
Single pressing: oil content of rapeseed and sunflower cake 10%
Pre-pressing: cakes with 15-18% oil
Residual oil removed by hexane: sunflower cakes with 2% oil and
rapeseed with 3.5% oil
Extrusion
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Alternative process giving good oil quality
90% yield by using acidic alcohol
Oil recovery; pressing and related processes
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Gas assisted mechanical expressing (GAME)
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CO2 supercritical above 31°C and 73 bar
Dissolution of CO2 in oil
Pressing efficiency increases
Main goal to develop continuous process
Novel process developed at A&F
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Oil extracted with CO2
Oil recovery; solvent extraction
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Organic solvents (hexane, petroleum ether)
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Supercritical fluids
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Solvent recovery
Hazardous solvents
High-value products
Few commercial application for commodity oils
Aqueous extractions
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Less effective in achieving high oil yield
Using enzymes improves oil extraction
Olives
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Different treatment compared to rapeseed and sunflower
seed
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By products
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Olive leaves
Olive cake
• Fuel in mill
• Fermentation
• Valuable products
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Olive mill waste water
Stones, pulp, molasses
Low residual oil content
Conclusions residual oil recovery
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Residual oil recovery
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Little is know about relation between process and properties of
(by)products
Efficiency of oil extraction process
Dependent of substrate (rapeseed, sunflower, olive)
Gas assisted mechanical expression process (GAME)
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High oil recovery without solvent extraction
Mild process: recovery of other products (proteins etc)
Continues process needed
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Novel supercritical extrusion-extraction
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Enzymatic extraction has potential
Remarks/questions
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