Parker Pure Water Series, Установка, эксплуатация и обслуживание

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GENERAL THEORY
3.4 FACTORS AFFECTING PERMEATE PRODUCTION
VARIATIONS IN TEMPERATURE, PRESSURE, AND SALINITY
The following table illustrates how the quality and quantity of permeate produced by a RO system is
affected by changes in temperature, salinity and pressure:
With constant.... And increasing....
Permeate
TDS Capacity
Salinity and Pressure Temperature Increases Increases
Temperature and Pressure Salinity* Increases Decreases
Temperature and Salinity Pressure** Decreases Increases
Table 3.1 - Factors Affecting Permeate Quality
*
If the feedwater salt concentration decreases, the product water flow rate should not be allowed to
increase more than 20% above rated flow. Feed pressure may need to be lowered to maintain
rated flow in brackish water or tap water applications.
**
Feed pressure shall not be increased above 950 psi.
The RO system can be adjusted to maintain a constant permeate output when feedwater temperature
and salinity is other than nominal. The operator can do this by controlling system pressure manually via
the backpressure regulation valve located in the system brine piping. As permeate flow decreases, the
operator can throttle the pressure regulation valve closed to increase system pressure. This, in turn,
will increase the permeate output and mitigate the effect of a decrease in temperature or an increase in
salinity. Conversely, the operator can open the pressure regulation valve to reduce pressure and
permeate flow in areas of excessively high temperature or low salinity.
IN FRESH OR BRACKISH FEEDWATER CONDITIONS, MAKE SURE TO REDUCE PRESSURE BY
TURNING REGULATOR. SET PRESSURE SO PRODUCT FLOW IS NO MORE THAN 120% OF
DESIGN FLOW TO AVOID MEMBRANE DAMAGE.