FCI Watermakers MAX-Q+, User Manual & Installation Manual

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FCI WATERMAKERS, INC. 6 FCI WATERMAKERS, INC. General
PRESSURE
The operating pressure has a direct effect on product water quality and quantity.
Both factors will increase as the system pressure increases (within design limits).
The system must be operated at the lowest pressure required to achieve
the designed product water flow rate. This parameter also minimizes
compaction, which occurs faster at higher pressures and temperatures.
At low temperatures or high salinity feed water, the system will have to operate at
higher than normal pressure to maintain the specified amount of product water
flow. This is normal and is due to the design characteristics of the system.
SPIRAL-WOUND MEMBRANE
The spiral‑wound membrane consists of multiple membrane envelopes, each
formed by enclosing a channelized product water carrying material between two
large flat membrane sheets. The membrane envelope is sealed on three edges with
a special adhesive and attached with the adhesive to a small diameter pipe.
A polypropylene screen is used to form the feed water channel between the membrane
envelopes. A wrap is applied to the membrane element to maintain the cylindrical
configuration. The center tube is also the permeate (product water) collecting channel.
Several elements may be connected in series within single pressure vessel
or multiple pressure vessels.
WATER TEMPERATURE EFFECT
The product water flow through the membrane is significantly affected
by the water temperature. At any given pressure, this flow increases with
increasing water temperature and is reduced at lower temperatures. The system
pressure will need to be adjusted to maintain a precise amount of product
water flow. For systems with APC, this adjustment will be automatic.
GLOSSARY OF TERMS
(continued)