GPS-X Technical Reference

Suspended Growth Models 164
The cross-flow solids removal rate (see Equation 6.45) is the mass of solids removed
from the filter cake, per unit of cross flow air, per unit surface area of the filter. The
default value is entered in the Input Parameters > Operational – Membrane > More …
form and is calibrated based on data in Garcia and Kanj (2002). The cross-flow airflow
(see Equation 6.45) is entered in the Input Parameters > Operational – Membrane
form. The default value gives airflow per surface area of 0.37 m 3 /m 2 /h
(see Wallis Lage et al., 2005) for the default membrane surface area. The cross-flow
airflow should be changed to reflect changes in the membrane surface area.
The cake layer resistance, R c, is calculated by combining Equation 6.44 and the Kozeny-
Carman equation for flow through porous passages as follows:
Equation 6.47
where:
dp
= effective cake particle diameter (m)
The default effective cake particle diameter is given in the Input
Parameters > Physical – Membrane > More…form, and is estimated using
information given in Shin et al. (2002).
The fouling resistance is calculated as follows (adapted from Choi et al., 2000):
Equation 6.48
where:
Rf,max = maximum fouling resistance (m -1 )
kf = fouling rate constant (d -1 )
t
= time since last recovery clean (d)
GPS-X Technical Reference