Abstract
A hydraulically sectioned columnar extractor is considered, which ensures ordered phase transport. The hydraulic and mass-transfer parameters of the extractor are calculated.
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Abbreviations
- A :
-
[l + (FTx/m)]/[1 + (Tx/m)]
- a :
-
specific interface area, m2/m3
- D c :
-
column diameter, m
- D :
-
coefficient of molecular diffusion in the dispersed phase, m2/s
- d con,d st,d circ :
-
diameters of the cone, stirrer, and circulation barrel, respectively, m
- d 32 :
-
mean volume-surface drop diameter, m
- E 1,E 2 :
-
longitudinal-dispersion coefficient of the continuous phase in a single- and two-phase flows, respectively, m2/s
- E t,E ax :
-
turbulent and axial components of the longitudinal-dispersion coefficient, m2/s
- E eff :
-
effective longitudinal diffusion coefficient in the circuit, m2/s
- F :
-
heat-transfer (extraction) factor
- g = 9.81:
-
free fall acceleration, m/s2
- h :
-
height equivalent to a theoretical stage, m
- h sec,h con h circ :
-
section, cone, and circulation-barrel heights, respectively, m
- i :
-
cell number along the raffinate flow
- K N :
-
power coefficient of the stirrer
- K x :
-
average surface mass-transfer coefficient, m/s
- L :
-
height of the working zone of the extractor, m
- l :
-
characteristic size of the circuit, m
- m :
-
number of perfectly mixed cells
- m distr :
-
distribution coefficient
- N :
-
power consumed by the stirrer, W
- n :
-
rotational speed of the stirrer, s-1
- Q :
-
total specific capacity, m3/(m2 h)
- R :
-
circulation factor
- r :
-
stirring radius, m
- T x :
-
observed total number of raffinate-transfer units
- t circ :
-
circulation time, s
- u :
-
apparent flow velocity, m3/(m2 s); velocity of the direct flow of the continuous phase, m/s
- u circuit :
-
flow velocity in the circuit, m/s
- u st :
-
peripheral velocity of the stirrer, m/s
- u circ :
-
circulation flow velocity, m/s
- u s :
-
relative velocity of the phases, m/s
- V :
-
volume of an extractor section, m3
- V*:
-
pumping capacity of the stirrer, m3/s
- V :
-
phase flow rate, m3/s; specific phase load, m3/(m2 h)
- w :
-
velocity of the reverse flow in the circuit, m/s
- x 1,x fin,x eq :
-
initial, final, and equilibrium concentrations, respectively, of the desired component in the raffinate, g/1
- x i y l :
-
current concentrations of the desired component in the raffinate and extract, respectively, g/1
- y in :
-
initial concentration of the desired component in the extract, g/1
- z :
-
relative height of the working zone of the extractor
- ψi, Γl :
-
dimensionless concentration of the desired component in the raffinate and extract, respectively
- ε:
-
specific power consumption, W/m3
- μ:
-
dynamic viscosity of a phase, Pa s
- v :
-
kinematic viscosity of a phase, m2 s
- ρ:
-
density, kg/m3
- σ:
-
interfacial tension, N/m
- Φdisp, Φcon, Φout :
-
retention capacity in the dispersion zone, inside the cone, and outside the section, respectively, m3/m3
- ω = πn/30:
-
angular velocity of the stirrer, s-1
- Pej =u cont L/E j :
-
Peclet number for the continuous phase (j= 1,2)
- Pe circuit=u circuit L/E eff :
-
Peclet number for the circuit
- Pedisp =u sd32/D :
-
modified Peclet number for the dispersed raffinate
- Prdiff :
-
diffusion Prandtl number
- Re =u sd32/vdisp :
-
modified Reynolds number for the dispersed raffinate
- Rest =nd st 2 ρ/u:
-
Reynolds number for the stirrer
- Shdisp =K xd32/D :
-
Sherwood number for the dispersed raffinate
- d:
-
dispersed phase
- cont:
-
continuous phase
- lim:
-
limiting
- em:
-
emulsion
References
Treybal, R.,Liquid Extraction, New York: McGraw-Hill, 1963.
Osnovy zhidkostnoi ekstraktsii (Fundamentals of Liquid Extraction), Yagodin, G.M., Ed., Moscow: Khimiya, 1981.
Pebalk, V.L., Hydraulics and Mass Transfer in Sectional Extractors with Mechanical Stirring,Doctoral (Eng.) Dissertation, Moscow: Lomonosov Inst. Fine Chem. Technol., 1970.
Varfolomeev, B.G., Dispersion of Liquids and Energy Intensity and Efficiency of Box-Type Extractors,Cand. Sci. (Eng.) Dissertation, Moscow: Lomonosov Inst. Fine Chem. Technol., 1973.
Strenk, F.,Peremeshivanie i apparaty s meshalkami (Stirring and Stirred Apparatuses), Leningrad: Khimiya, 1975.
Kostanyan, A.E., Dil’man, V.V., and Vasin, A.A., Dwell Time for a Flow Circuit,Teor. Osn. Khim. Tekhnol, 1982, vol. 16, no. 6, p. 790.
Tsiklauri, N.G., Hydraulic and Mass-Transfer Characteristics of a Sectional Extractor with an Organized Flow Structure,Cand. Sci. (Eng.) Dissertation, Moscow: Lomonosov Inst. Fine Chem. Technol., 1987.
Gel’perin, N.I., Pebalk, V.L., and Kostanyan, A.E.,Struktura potokov i effektivnost’ kolonnykh apparatov khimicheskoi promyshlennosti (Flow Structure and Efficiency of Industrial Columnar Apparatuses), Moscow: Khimiya, 1977.
Brounshtein, B.I. and Zheleznyak, A.S.,Fizikokhimicheskie osnovy zhidkostnoi ekstraktsii (Physicochemical Foundations of Liquid Extraction), Moscow: Khimiya, 1966.
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Varfolomeev, B.G., Pebalk, V.L., Kostanyan, A.E. et al. Hydraulically sectioned columnar extractor. Theor Found Chem Eng 34, 255–262 (2000). https://doi.org/10.1007/BF02755973
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DOI: https://doi.org/10.1007/BF02755973