TM 10-4610-310-14
0043 00
OPERATOR MAINTENANCE
LIGHTWEIGHT WATER PURIFIER
REVERSE OSMOSIS MEMBRANE
CLEANING
INITIAL SETUP
Materials/Parts
Special Environmental Conditions
High pH cleaner (item 10, WP 0136 00)
Do not allow drainage to contaminate source
Low pH cleaner (item 11, WP 0136 00)
Equipment Condition Required.
Tools
All equipment de-energized
Paddle, stirring, (PN 3485K14)
Water in product tank
Immersion heater, 2000-watt, (PN 2850332001)
Tool Kit (PN 3600486000)
Adapter, cleaning, (PN 2554647000)
Stop watch (table 2, item 49, WP 0135 00)
GENERAL
This work package contains information and instructions to clean the Reverse Osmosis (RO) membranes in the
RO module in the Lightweight Water Purifier (LWP). The cleaning process includes product flush, high pH
cleaning and low pH cleaning.
CLEANING PARAMETERS
Reverse osmosis membrane elements should be cleaned when:
The permeate flow decreases by 10% from the mission start
The salt content of the product water increases by 10% from the mission start
The differential pressure increases by 15% from the mission start
The system operating pressure reaches the limit set in Table 1.
NOTE
The following table is to be used as a supplemental guidance to determine the RO membrane cleaning
requirement. The product quality, production quantity, environmental effects and past performance
characteristic of the unit must also be taken into consideration. The unit must produce 2.1 gpm under 20,
000 ppm and 1.25 gpm at or above 20, 000 ppm source water. Product quality must always be less than
1000 ppm.
Table 1. Reverse Osmosis Cleaning Limit.
Feed (TDS)
Feed temp. Permeate flow Operating pressure
LIMIT
ppm
(F)
(gpm)
(psi)
(psi)
0-5,000
50-90
2.1
0-484
550
5,000-10,000
50-90
2.1
484-597
650
10,000-15,000
50-90
2.1
597-717
800
15,000-19,999
50-90
2.1
717-843
950
20,000 - 25,000
50-90
1.25
548-632
700
25,000 - 30,000
50-90
1.25
632-717
800
30,000 - 35,000
50-90
1.25
717-806
900
35,000 - 40,000
50-90
1.25
806-898
1000
40,000 - 45,000
50-90
1.25
898-996
1100
45,000 - 50,000
50-90
1.25
996-1100
1200
50,000 - 55,000
50-90
1.1-0.96
1100-1200
N/A
55,000 - 60,000
50-90
0.96
1200
N/A
