TM 10-4610-241-24
TO 40W4-13-42
1-14. COMPONENT PRINCIPLES OF OPERATION.
The following paragraphs describe the principles of operation for components and assemblies of the ROWPU. Refer to
figure 1-5.
CAUTION
Source water must be free of chlorine. Chlorine will instantly destroy the R.O. elements.
Destruction of the R.O. elements will make the ROWPU unable to perform its mission.
RAW WATER SOURCE (1). The raw water source can be any reservoir of fresh, brackish or saltwater. Water source
should contain enough water to perform your mission.
STRAINER (2). The strainer prevents small stones, twigs and debris from entering suction hose.
OCEAN INTAKE STRUCTURE (2a) (Models H-9518-1, H-9518-2, and H-9518-3). Utilizes self-jetting wellpoints to
extract water from a variety of water sources, but especially from an ocean-type environment.
RAW WATER PUMPS (3 and 4). Two portable, electrically driven, centrifugal pumps draw raw water from the water
source and supply it to the ROWPU under pressure. These pumps are normally connected in series. One pump is used in the
product water system during NBC operations to pressurize the water flow through the deionization cartridges.
CHEMICAL FEED PUMP. The chemical feed pump consists of an electric motor, housing, four feed heads and four
stroke adjustment assemblies. The electric motor turns a camshaft inside the housing. A shaft inside each stroke adjustment
assembly converts the rotating action of the camshaft to a reciprocating stroke that operates a diaphragm inside each feed
head. Each feed head performs the following function:
POLYMER FEED HEAD (5). Adds the polymer solution to the raw water to coagulate solids in multimedia filter.
SODIUM HEX FEED HEAD (6). Adds diluted sodium hex to the raw water to prevent scaling and corrosion.
CHLORINE FEED HEAD (13). Adds chlorine to the product water after the R.O. process takes place. Chlorine
reduces bacteria in the product water to a level safe for human consumption.
CITRIC ACID FEED HEAD (17). Adds diluted citric acid to filtered water to maintain the optimal pH (5.0 - 8.0)
for the R.O. process; aids in preventing scale buildup inside the R.O. membranes.
MULTIMEDIA FILTER (7). Removes large suspended solids from the raw water. The multimedia filter contains six
types of media: gravel, coarse garnet, fine garnet, silica sand, anthracite, and plastic, Water entering the filter flows through a
baffle to prevent disruption of the filter media. The water then flows through the filter media leaving larger suspended solids
behind. The media bed is backwashed when: the loss of head pressure through the filter bed increases above a certain level;
or the quality of the water flowing out fails to meet standards.
BOOSTER PUMP (8). Electrically driven, centrifugal pump increases water pressure to the cartridge filter.
1-6 Change 1
