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Chapter 7. Solvent Cycle, Methods for Solute Precipitation. Heat and Mass Transfer: High Pressure chemical Engineering I (WS). Flow Scheme of a Solvent Cycle. Solvent Cycle. Solvent Cycle Steps: separate the extract from the solvent (1), clean the solvent for reuse (2),
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Chapter 7 Solvent Cycle, Methods for Solute Precipitation Heat and Mass Transfer: High Pressure chemical Engineering I (WS)
Solvent Cycle Solvent Cycle Steps: separate the extract from the solvent (1), clean the solvent for reuse (2), remove the solvent from raffinate (3), adjust composition of solvent mixture (if applicable) (4).
SFE Modes of Operation Single stage Multiple stage Counter- Chromato- (precipitation) current graphic
Solvent Cycle: Solvent to feed ratio of SFE processes Extraction From Solids StS / F Essential oils (5 %) 20 < 1 > 20 Edible oils (2 %) 40 < 1 40 Coffee decaffeination (0.01 %) 200 5 40 Black tea decaff. (0.01 %) 230 1.5 150 Total amount of solvent S, kg/kgF Extraction time t, h Solvent to Feed Ratio S/F, kgS /(kgF h) Basis: Solvent: Carbon dioxide 10 - 30 MPa, 330 K
Solvent Cycle: Solvent to feed ratio of SFE processes Countercurrent Separation V/LvS / F FAEE, FAME (5 %) 20 7.5 125 FFA (fatty acids) (2 %) 50 4.5 50 Squalene (1.5 %) 20 10 50 Tocopherol-Purif. (2.5 %) 35 20 45 Solvent ratio V/L, kg/kg Reflux ratio v, - Solvent to feed ratio S/F, kgF /kgF Basis: Solvent: Carbon dioxide 10 - 30 MPa, 350 K
Solvent Cycle: Solvent to feed ratio of SFE processes Chromatographic Separation PrtrS / F DHA / DPA 1.5 15 900 x 103 EM Phytol-isomers 10- 30 6 900 EM 200 SMB Productivity Pr, gP /(kgStPh h) Retention time, min Solvent to feed ratio S/F, kgF /kgF Basis: Solvent: Carbon dioxide 10 - 30 MPa, 310 K
Modes For Product Recovery Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment ......
Solubility of Caffeine in CO2 Birtigh, Brunner, Johannsen
Energy Consumption by Various Solvent Cycles Extraction temperature: 313 K
Energy needed for the gas cycle for S/F 125 kg/kg: Mechanical Energy Thermal energy in Thermal energy out 70 kJ/kgCO2 Pump with heat recovery 8750 kJ/kgFeed Pump without heat recovery Extraction pressure [MPa] Compressor with heat recovery 95 kJ/kgCO2 Compressor without heat recovery 11875 kJ/kgFeed Energy [kJ/kg]
Modes For Product Recovery Reduction of pressure or density (temperature) Anti solvent Membrane separation Adsorption Absorption De-Entrainment
Solubility in a Gas With a Modifier (Entrainer) Influence of temperature Brunner 1983
Solubility of Caffeine in CO2 Data by: Gährs 1984 Ebeling, Franck 1984 Johannsen, Brunner 1994
Modes For Product Recovery Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment ......
Anti-Solvent: Solubility of Caffeine in CO2 Influence of nitrogen Gährs 1984
Modes For Product Recovery Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment ......
Retentate OC CO2 Permeate Separation by Membranes p = 2.0 MPa active dense layer 1.5 mole CO2 kg/(m2 h) < 0.06 wt.-% 1.86 wt.-% P = 18 MPa, T = 323 K GKSS-membrane (organic, active dense layer)
Solvent Cycle in a T,s - Diagram Compressor mode CO 2 Extraction/ Precipitation at separation D low p Temperature Precipitation at D high p Entropy
Energy For Different Solvent Cycles Pump-Cycle 53 kJ/ kgCO2 Compressor-Cycle 21 kJ/ kgCO2 Membrane-Cycle Like in 2 7.6 kJ/ kgCO2 Sartorelli 2001
Modes For Product Recovery Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment ......
Recovery of Tocopherolacetate by Adsorption Silica with 50% loading, loaded by mixing, conventional process Silica with 52% loading,loaded by high pressure adsorption
Modes For Product Recovery Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment ......
Modes For Product Recovery Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment ......
Solubility in a Gas With a Modifier (Entrainer) Influence of temperature Brunner 1983
De-Entrainment Birtigh
Generalization of Precipitation: Membership - Functions (x): relative number of statements from people at the pool 1 „Hot“ Too hot Not yet hot (x) 0 25 35 45 T [oC] x Temperature at the Swimming Pool
Membership Functions P Adsorption Membrane Birtigh
Absorption De-Entrain T T Membership Functions Birtigh