Updated Datasheet 2022
Updated Datasheet 2022
Updated Datasheet 2022
School of Engineering
,
fc is 0.005 for gases
= (z1 – z3) 1g + z3 2g = z2 2g
Cornell’s Method
Height of Gas-phase transfer unit , m Height of Liquid-phase transfer unit , m schmidt number
( ) . ( . . ∗ . ( ) . . Sc = / D
= 0.011 ) ( ) /( ) = 0.305 ( )
0.305 3.05 3.05
liquid viscosity correction factor = f1= ( ) . liquid density correction factor = f2= ( ) .
surface tension correction factor = f3= ( ) .
Onda’s Method
Effective Area Gas film transfer unit height
. ∗ . ∗ . ∗ .
= 1 − exp [−1.45 ] =
Liquid phase mass transfer coefficient, kmol/m2 (kmol/m3) = m/s Liquid film transfer unit height
/ ∗ / /
.
= 0.0051 =
Gas film mass transfer coefficient , , kmol/m2s atm or kmol/m2 s bar
∗ . /
.
=
Material c mN/m
Ceramic 61
Metal (steel) 75
Plastic (polyethylene) 33
Carbon 56
( )
= + + + ∗ + ∗ (ℎ ) = 0.95 , Γ = ; = 2 3
Bundle Diameter Film boiling coefficient condensation inside-outside vertical tubes
.
d = P − 0.917d (For a triangular pitch)
Critical heat flux [ zuber ]
∆ = ( − ) ; = , ,
;
= ; =
∆ = 8∗ ∗ ∗ + 2.5 ∗
Recovery of ith component in distillate vapour and liquid concentrations of Minimum number of stages; Fenske equation, Minimum number of stages (Fenske
the light key equation)
log( )
=
Tray Efficiency
Murphree plate efficiency Overall column efficiency The point efficiency is related to the number of transfer units
, , by the equation:
, = , = 1
, , , 1 mV 1
ln(1 Emv ) NG L NL
overall column efficiency can be obtained from the O’Connell’s correlation for absorber Van Winkle’s correlation
correlation given by O’Connell
EmV = 0.07Dg0.14Sc0.25Re0.08
= 51 − 32.5 ( ) = 0.0062 = 0.062
Surface tension number Dg = (L / L uv ) liquid Schmidt number Sc = (L / L DLK) Reynolds number Re = (hwuv v/ L (FA));
The number of liquid phase transfer units is given by: ℎ
NL = (4.13 x 108DL)0.5 (0.21Fv + 0.15)tL ( ) =
the column vapour “F” factor = √
Number of gas phase transfer units the Peclet number The column diameter, Dc:
(0.776 + 4.57 ∗ 10 ∗ ℎ − 0.24 + 105 )
= =
( ) .
The total hole area as a fraction of the Plate pressure drop The pressure drop through the dry plate Residual head
perforated area, for an equilateral -3 12.5 ∗ 10
Pt = 9.81 x 10 ht L
triangular pitch: ℎ =
ℎ = 51 ( ) * ,
= 0.9 ( ) ,
In terms of clear liquid the head loss in the downcomer The clearance area under the downcomer is
The total plate drop:
downcomer back-up is given by: given by:
ht = hd + (hw + how )+ hr ℎ = 166 [ ]
hb = hw + how + ht + hdc Aap = hap lw
The downcomer residence time
ℎ
=