TM 10-4610-240-10
TM 08580C-10/1
T.O. 40W4-13-21
11-8. PIPING IDENTIFICATION.
The ROWPU piping is identified according to function by the following colors:
Function:
Color:
Raw Water
Black band
Backwash waste
Red band
Filtered Water
Yellow band
Product water
Blue band
Brine discharge
Purple band
Brine Piping on R.O. pressure vessels
Purple band
Section III. TECHNICAL PRINCIPLES OF OPERATION
Page
Water processing and Chemicals ..............................................................................................................................1-17
Reverse Osmosis (R.O.) Process...............................................................................................................................1-18
1-9. WATER PROCESSING AND CHEMICALS.
The ROWPU removes suspended solids (called turbidity), chemicals, and solids held in solution (called dissolved solids),
found in most fresh water and seawater sources, to a level fit for human consumption. This is done by filtering with the
aid of the reverse osmosis process, and then additional purification using selected chemicals. Refer to figure 1-15 to
follow the process described below.
a. First Stage of Filtration-Multimedia Filter. Before raw (untreated) water reaches the multimedia filter, polymer
solution is added to it. Polymer collects suspended solids into groups large enough to be removed by the multimedia
filter. This process is called coagulation. Water is then filtered through the multimedia filter.
b. Second Stage of Filtration-Cartridge Filter. The cartridge filter takes out finer suspended solids that pass through
the multimedia filter.
c. Reverse Osmosis (R.O.) Elements. The first two stages of filtering do not remove dissolved solids from the
water. The R.O. elements, through the R.O. process, remove dissolved minerals and any suspended solids that may
have passed through the filters.
d. Chlorine Disinfection. As the water leaves the ROWPU, chlorine is added as a disinfectant to reduce and
maintain at an acceptable level any bacteria present in the product water. At this point, the product water is stored for
human consumption.
1-17
