Page 19 - Separation process principles 2

Nomenclature xxiii

equilibrium ratio for vapor-liquid equilibria; LES length of equilibrium (spent) section of adsorp-
equilibrium partition coefficient in (3-53) and tion bed
for a component distributed between a fluid LUB length of unused bed in adsorption
and a membrane; overall mass-transfer coeffi-
cient; adsorption equilibrium constant Lw weir length
1 constant in UNIQUAC and UNIFAC equa-
overall mass-transfer coefficient for UM
tions; component flow rate in liquid; length
diffusion
binary interaction parameter
chemical equilibrium constant based on
activities membrane thickness
solubility product; overall mass-transfer coeffi- packed height
cient for crystallization molecular weight; mixing-point amount or
equilibrium ratio for liquid-liquid equilibria flow rate, molar liquid holdup
equilibrium ratio in mole- or mass-ratio com- moles of i in batch still
positions for liquid-liquid equilibria
residual of component material-balance equa-
overall mass-transfer coefficient based on the tion (10-1)
gas phase with a partial pressure driving force
mass of crystals per unit volume of magma
molar selectivity coefficient in ion exchange
total mass
overall mass-transfer coefficient based on the
slope of equilibrium curve; mass flow rate;
liquid phase with a concentration driving force
mass
capacity parameter defined by (6-53)
mass of crystals per unit volume of mother
wall factor given by (6-1 11) liquor
overall mass-transfer coefficient based on the molality of i in solution
liquid phase with a mole ratio driving force
mass of adsorbent or particle
overall mass-transfer coefficient based on the
mass of solid on a dry basis; solids flow rate
liquid phase with a mole-fraction driving force
mass evaporated; rate of evaporation
overall mass-transfer coefficient based on the
gas phase with a mole ratio driving force tangent to the vapor-liquid equilibrium line in
the region of liquid-film mole fractions as in
overall mass-transfer coefficient based on the
Figure 3.22
gas phase with a mole-fraction driving force
tangent to the vapor-liquid equilibrium line
restrictive factor for diffusion in a pore
in the region of gas-film mole fractions as in
thermal conductivity; mass-transfer coefficient Figure 3.22
in the absence of the bulk-flow effect
MTZ length of mass-transfer zone in adsorption bed
mass-transfer coefficient that takes into ac-
N number of phases; number of moles; molar
count the bulk-flow effect as in (3-229) and
flux = n/A; number of equilibrium (theoreti-
(3-230)
cal, perfect) stages; rate of rotation; number of
mass-transfer coefficient based on a concentra- transfer units; cumulative number of crystals of
tion, c, driving force; thermal conductivity of size, L, and smaller; number of stable nodes;
crystal layer molar flow rate
binary interaction parameter number of additional variables; Avogadro's
mass-transfer coefficient for integration into number molecules/mol
crystal lattice number of actual trays
constant Biot number for heat transfer
constant Biot number for mass transfer
mass-transfer coefficient for the gas phase number of degrees of freedom
based on a partial pressure, p, driving force
number of independent equations
mass-transfer coefficient for the liquid phase
Eotvos number defined by (8-49)
based on a mole-fraction driving force
Fourier number for heat transfer = at/a2 =
mass-transfer coefficient for the gas phase
dimensionless time
based on a mole-fraction driving force
Fourier number for mass transfer = ~t/a~ =
liquid molar flow rate in stripping section
dimensionless time
liquid; length; height; liquid flow rate; under-
Froude number = inertial forcelgravitational
flow flow rate; crystal size
force
solute-free liquid molar flow rate; liquid molar
number of gas-phase transfer units defined in
flow rate in an intermediate section of a column
Table 6.7
length of adsorption bed
number of liquid-phase transfer units defined in
entry length Table 6.7
predominant crystal size
Lewis number = Ns,/Np,
liquid molar flow rate of sidestream