GE E4LE - Manual (Page 9)

2.7 Pressure Correction Factors
It is often necessary to operate RO machines with permeate back pressure. Permeate
back pressure will decrease permeate production. See Table 2.3 (Pressure Correction
Factors) to calculate loss of permeate.
Table 2.3
Pressure Correction
Factors
WARNING: IF PERMEATE BACK PRESSURE EXCEEDS 60 PSIG (4.1 BARG)
MACHINE DAMAGE MAY OCCUR.
WARNING: INSTALLING A CHECK VALVE WILL PREVENT REVERSE FLOW
THROUGH THE MEMBRANE ELEMENT WHEN THE MACHINE IS NOT
IN OPERATION. REVERSE FLOW, WHEN THE MACHINE IS NOT IN
OPERATION, CAN SEVERELY DAMAGE THE MEMBRANE ELEMENTS.
4
BACK PRESSURE
10 psig (0.7 barg)
20 psig (1.4 barg)
30 psig (2.0 barg)
40 psig (2.7 barg)
50 psig (3.4 barg)
60 psig (4.1 barg)
% LOSS OF
PERMEATE FLOW
E4/EZ4 E4LE
5% 10%
10% 20%
15% 30%
20% 40%
25% 50%
30% 60%
PRESSURE
CORRECTION
FACTOR (PCF)
E4/EZ4 E4LE
0.95 0.90
0.90 0.80
0.80 0.70
0.70 0.60
0.60 0.50
0.50 0.40