R
Ideal gas constant, J mol
À1 K
À1
r c
Crystal radius, m part
Rec
Recovery, %
R p
Particle radius, m part
t
Time, s
T 1
Ambient temperature, K
T b
Boiling temperature, K
T c
Critical temperature, K
t cycle
Duration of one cycle, s
T g
Bulk phase temperature, K
T p
Solid temperature, K
T w
Wall temperature, K
U
Overall heat transfer coefficient, J s
À1 K
À1 m wall
À2
u 0
Superficial velocity, m fluid
3 m bed
À2 s
À1
V s
Adsorbent volume, m
3
x i
Mole fraction of component i in the adsorbed phase at equilibrium, - - -
x j
Mole fraction of component j in the adsorbed phase at equilibrium, - - -
y i
Mole fraction of component i in the fluid phase at equilibrium, - - -
y j
Mole fraction of component j in the fluid phase at equilibrium, - - -
z
Axial position, m bed
Z
Zone, - - -
Τ
Temperature, K
Symbol
α w
Ratio of the internal surface area to the volume of the column wall, m wall
À1
α w‘
Ratio of the log mean surface to the volume of column wall, m wall
À1
ΔH
Heat of adsorption, J mol
À1
ΔH 0 Heat of adsorption at zero coverage, J mol
À1
Δq i
Working capacity for components i, mol kg s
À1
Δq j
Working capacity for components j, mol kg s
À1
ε
Bed porosity, m fluid
3 m bed
À3
ε p
Particle porosity, m pores
3 m part
À3
λ
Heat axial dispersion coefficient, J s
À1 m bed
À1 K
À1
μ
Bulk gas mixture viscosity, kg fluid m fluid
À1 s
À1
ρ
Bulk gas mixture density, kg fluid m fluid
À3
ρ ads
Density of the adsorbed phase, kg gas m
À3
ρ g
Adsorbate gas density, kg gas m
À3
ρ p
Particle density, kg solid m part
À3
ρ w
Wall density, kg wall m wall
À3
Ω
LDF factor, - - -
Abbreviation
CAGR
Compound annual growth rate
CSS
Cyclic steady state
DSL
Dual-site Langmuir
188
V. F. D. Martins et al.