BWS1500 System Installation, Operation & Maintenance
18
Introduction
The Reverse Osmosis membrane uses pressure to allow
pure water molecules to filter through its semipermeable
membrane separating pure water from dissolved solids
(salts) and other contaminants. In essence the membrane
splits feed water into two separate streams. One stream is
the water produced for use (product or pure water), and the
other contains the salts and contaminants filtered out by the
membrane (reject) carried away to the drain. The OptiPure
BWS1500 is designed to produce water at a 30% recovery
rate which means it uses water at a ratio two gallons of
reject water for each gallon of pure water produced. This is a
Product/Reject Ratio of 1/2
.
The “pure water” produced by the membrane is not always
appropriate for use with food service equipment. The
BWS1500 system also allows blending filtered water with
the pure water to produce
Optimized Water
which can be
adjusted to provide the ideal characteristics for food service
equipment applications. Instructions for blending Optimized
water are on page 11.
Each system is adjusted at the factory for the proper
operating parameters.
In most cases the factory setting should not be changed.
However, due to certain conditions, an adjustment may
produce better operating efficiency and membrane
performance. Conditions that can influence the ideal
Product/Reject Flow Rate Ratio include feed water quality
(TDS level, Turbidity and specific contaminants such as
iron and silica), water temperature and water pressure. The
determination of whether to make a Product/Reject Flow
Rate adjustment is complex. An understanding of your water
chemistry and operating conditions is necessary in order
to safely deviate from the factory setting.
It is strongly
recommended that you contact your OptiPure dealer or
the factory for assistance before changing the factory
setting.
Permeate Flow Rate Adjustment
The processed water (permeate) flow rate is directly
proportional to the system operating pressure (e.g. higher
pressure = higher flow, lower pressure = lower flow). The
system is set at the factory for proper operation at 70° F. The
operating pressure can be increased to compensate for low
temperature feed water, but only if the water temperature
will not later go up without a corresponding adjustment
being made to the operating pressure. The maximum safe
permeate flow rate is
1200 gpd/50 gph/0.83 gpm (4500
liters per day/190 liters per hour/3200 milliliters per
minute)
. Under no condition is it safe to operate the system
at higher permeate flow rates. Likewise, if your water
temperature is higher than 70° F, you should reduce the
operating pressure to bring the permeate flow rate down
to 1200 gpd. If you increase the operating pressure to
compensate for cold water in the winter, be sure to reduce
the pressure once the water warms up. Before making any
adjustment, turn the Blending Valve clockwise until it is
closed all the way. Remove Processor plastic cover. Locate
the pressure regulator on the right side of the Processor (see
photo). Loosen the lock nut on the regulator handle.
NOTE: The handle of the regulator should never be
loosened by more than a turn or two, as loosening all
the way will allow the handle to come off and water to
spray out of the regulator.
Do not raise the operating pressure higher than 150 psi.
To increase the system operating pressure (and permeate
flow rate), turn the knob of the pressure regulator clockwise.
To decrease the pressure, turn it counterclockwise. After
achieving the desired pressure, tighten the lock nut on the
regulator. See “Measuring Product Flow Rate” on the next
page.
Reject Flow Rate Adjustment
The
Reject Flow Rate
is the amount of water used to carry
away the impurities rejected by the membrane. It is critical
that both the Product Flow Rate and the Reject Flow Rate
are measured to confirm the desired Product/Reject Ratio
has been achieved. The higher the ratio of product flow to
reject flow, the shorter the life of the membrane will be.
IMPORTANT: Never close the Reject Flow Control Valve,
and never adjust it such that the Reject flow rate is less
than the Permeate (Product) flow rate! This will cause
premature fouling and shorten membrane life.
To adjust the reject flow rate, locate the reject flow
control valve. Loosen the lock-nut (at the base of the valve
stem) just slightly.
IMPORTANT: Before adjusting Reject Flow Rate
CLOSE
the BLENDING VALVE (turn clockwise all the way).
Product/Reject Flow Rate Adjustments
Reject Flow
Control
(Adjust with
Blend Valve
Closed)
– Never close it
nor limit Reject
flow to less
than Permeate
flow!
Pressure
Regulator
(Permeate
Flow Control)
Adjust with Blend
Valve Closed
