Amiad Water Systems | 2019
TEQUATIC™ PLUS F-150 Filter, C-series Skid
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Operation
4. Wait for the system to normalize and stabilize, and check the brush speed again.
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Note: During the CIP cycle, the recirculation pump speed can be adjusted to a higher setting.
4.4.3 Filtrate Flow Rate
The filtrate flow rate is controlled by filtrate proportional valve. The valve will open partially to let
water out of the system. The open percentage of the valve can be controlled using either PID loops or
by manually setting the open percentage. A standard skid can utilize a PID loop to target a DP value
allowing maximum possible flow and adjusting as the feedwater particle concentrations fluctuate.
With the installation of a flow meter, the skid can target a desired flow rate adjusting as necessary.
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The DP target for the PID control loop should be set relatively low. Setting this value too high
will result in excessive flow and result in DP events lowering the efficiency of the filter. For most
applications the DP target should remain below 0.8 psid.
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The flow target for the PID loop will open and close the
filtrate valve to meet the desired setpoint. This function
is especially useful if the facility is also using chemical
dosing based on flow rate.
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The manual setting of the filtrate valve will hold it at
a specified open percentage letting the flow and DP
values fluctuate as the filter condition changes.
The desired result of controlling the flowrate is to allow
the filter to run continuously with minimal cleaning
cycles. A stable DP value is the best indication that the
filter is running within specifications and performing well. These guidelines should be followed to
determine the optimal flowrate:
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The stable DP should remain low. It should never exceed 1.2 psid for prolonged operation and most
application remain below 0.8 psid.
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Fluctuations in the DP (± 0.3 psid) or a steadily climbing DP indicate the flow is set too high and
needs to be reduced.
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Frequent DP-triggered cleaning cycles indicate the flow is too high or the brush configuration needs
to be more aggressive.
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The filtrate flowrate should be set in conjunction with the cleaning assembly RPM to ensure stable
DP in the short 3-8-minute interval. If DP begins to rise uncontrollably the flowrate should be
reduced.
