GE P&W Spiral Wound Membranes - Duratherm STD Series - Manual (Page 2)

Page 2 FS1271EN
Table 2: Dimensions and Weight
Model 1
Dimensions, inches (cm) Boxed
A B 2 C 3
Weight
lbs (kg)
Duratherm STD RO4040
40.0
(101.6)
0.625
(1.59)
3.9
(9.9)
9
(4.1)
Duratherm STD RO8040
40.0
(101.6)
1.125
(2.86)
7.9
(20.1)
29
(13.2)
Duratherm STD
UF8040HR 40.0
(101.6)
1.125
(2.86)
7.9
(20.1)
29
(13.2)
1 These elements are dried and bagged before shipping.
2 Internal diameter unless specified OD (outside diameter).
3 The element diameter (dimension C) is designed for optimum performance in
GE pressure vessels. Other pressure vessel dimension and tolerance may result
in excessive bypass and loss of capacity
Table 3: Temperatures
Do not exceed 20 GFD (34LMH) in any circumstances
Model
Maximum
operating
temperature
Maximum
cleaning
temperature
Maximum
sanitization
temperature
Duratherm STD RO 158°F (70°C) 122°F (50°C) 194°F (90°C)
Duratherm STD UF 158°F (70°C) 122°F (50°C) 194°F (90°C)
Table 4: Pressures and operating parameters
Model
Max operating pressure
Rec.
element
recovery
Typical
operating
flux
41–122°F
(5–50°C)
124–158°F
(51–70°C)
Duratherm STD RO
600psi
(4,137kPa)
400psi
(2,758kPa)
<15%
10-18GFD
(17-31LMH)
Duratherm STD UF
600psi
(4,137kPa)
80psi
(522kPa)
<15%
10-25GFD
(17-40LMH)
Table 5: Operating and CIP parameters
Model
pH range
Chlorine
tolerance
Feed
water Continuous
operation
Clean-In-
Place (CIP)
Duratherm STD RO 4.0 – 11.0 2.0-11.5
500 ppm-hours,
dechlorination
recommended
NTU < 1
SDI < 5
Duratherm STD UF 4.0 – 11.0 2.0-11.5
5,000 ppm-
days,
dechlorination
recommended
NTU < 1
SDI < 5
Hot Water Sanitization
recommendations:
For optimal performance, Duratherm STD ele-
ments should always be cleaned using approved
CIP procedures and flushed with fouling free wa-
ter before the sanitization process. Feed pressure
during sanitization should not exceed 40psi
(275kPa) and the crossflow should not incur a
pressure drop greater than 2psi (14kPa) per ele-
ment. Heating rate to sanitizing temperature and
cool down should not be faster than 5°C (41°F)
per minute. Maximum sanitization temperature is
90°C (194°F).
Loss of permeate flow after repeated
90°C (194°F) sanitization cycles
It is almost impossible to exactly predict the per-
centage of permeate flow rate lost from the high
temperature sanitations, which among other fac-
tors depends on:
1) Rate of temperature increase and decrease.
2) Presence of other species like organics, ionic
and metallic compounds that could locally de-
crease or increase the temperature at the sur-
face of the membrane.
3) Feed flow rate and specifically the heat trans-
fer rate to the membrane surface.
4) The thickness and geometry of the feed spac-
er used.
At optimum conditions measured in controlled
environment with deionized water, between 30%
and 50% of the original permeate flow rate was
lost before the element performance had stabi-
lized after repeated heat treatments (over 90% of
this flow reduction occurred during the first heat
treatment). With the loss of permeate flow rate,
the salt rejection increases. The rate of cooling
and heating was not more than 5
 C (41°F) per mi-
nute, and the differential pressure drop per ele-
ment did not exceed 2 psi.
Pilot testing based on the criteria noted above will
give the best operating parameters for any specif-
ic application.
Salt Rejection
Figure 1: NaCl rejection for STD RO element