TM 10-4610-239-24
TM 08580B-24/3
Flow is in the direction opposite to that followed by the raw water during filtration, so trapped particles are forced
from the filter and are discharged through a drain connected to the top of the multimedia filter.
g.
A brine and citric acid solution or detergent solution is circulated through the R.O. elements to clean them. Citric
acid or detergent is added to brine that remains in the backwash water tank after backwash is complete. The
backwash pump is then connected to the input of the R.O. elements. This routes the solution through the
elements, then back to the backwash water tank. When repeated recirculation has cleaned the R.O. elements,
the ROWPU is operated normally to remove residue and drain it outside the product water tank.
h.
When chemical or nuclear contaminants are present in product water, they are filtered out between the two
product water tanks. The ROWPU is overpacked with two portable filters that can be connected with one of the
raw water pumps in the line that connects the two tanks. One of the filters is used when the water is
contaminated with chemicals. The other filter is used for nuclear contaminants.
1-14.
FUNCTION OF MAIN COMPONENTS.
1.
SUCTION HOSE STRAINER. Prevents large pieces of trash from entering system.
2.
FLOAT. Holds suction hose strainer between surface and bottom of raw water source.
3.
RAW WATER PUMPS. Draw raw water through suction hose strainer and send it under pressure to multimedia
filter. When chemical or radiological filters are used in the product water line, one raw water pump is used
between the two product water tanks to force water through the filter.
4.
CHEMICAL FEED METERING PUMP ASSEMBLY. Draws chemical solutions from cans and injects them into
water at various points in purification system.
5.
CHEMICAL FEED METERING PUMP MOTOR. Provides power for four chemical feed metering pump drive
units.
6.
POLYMER DRIVE UNIT. Adds polymer solution to raw water. Polymer solution collects small pieces of floating
solid matter into groups large enough to be removed by multimedia filter.
7.
SODIUM HEX DRIVE UNIT. Adds sodium hex to raw water. Sodium hex prevents scaling.
8.
CITRIC ACID DRIVE UNIT. Adds citric acid to output of multimedia filter prior to ROWPU shutdown. Citric acid
removes scaling developed in system during operation.
9.
RAW WATER FLOW METER. Indicates rate of flow of water drawn in by raw water pumps.
10.
BACKWASH VALVE. In NORMAL position, allows raw water to enter multimedia filter and closes the backwash
line. In BACKWASH position, allows brine to enter multimedia filter and closes raw water line.
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