26
5. Temperature Correction Factor
The permeability of the membrane is influenced by temperature mainly because
the water viscosity changes with temperature. When you evaluate the
permeability correctly, you need to eliminate the temperature effect with the
temperature correction factor (TCF) shown in Fig. 6.
A Trans-Membrane Pressure (TMP) measured at some real temperature can be
converted to 25 degree C corrected TMP with multiplying by TCF at real
temperature shown in Fig. 6.
A filtrate flow rate measured at some real temperature can be converted to 25
degree C corrected filtrate flow rate with divided by TCF at real temperature
shown in Fig. 6.
The equation for calculating TCF at a temperature (T degree C) is as follows.
TCF = 0.0008902 / (0.01257187 x EXP((1
－
0.005806436 x (273.15 + T)) /
(0.001130911 x (273.15 + T) - 0.000005723952 x (273.15 + T) x (273.15 + T))) / 1000)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
0
10
20
30
40
膜供給水温度 (℃)
温度
補正
係数
(
-
)
Feed water temperature
Temperature
correction
factor
Fig. 6 Temperature correction factor (TCF)
