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3D TRASAR
5500 - Installation & Operation Manual
5.2.3 3D TRASAR Scale Blowdown Control: 2-Drum Program Overview
Initial start-up for 2-Drum 3D TRASAR Scale Blowdown Control is a 4-Step process. This process is
necessary for product transition and for the 3D TRASAR controller to learn the average scaling stress
of your cooling system and develop the appropriate control responses to optimize the treatment pro-
gram.
3D Scale
Blowdown
Control
2-Drum
Program Start-Up Overview
Time
Before
•TRASAR
Control
•TRASAR
Control
•
Monitor
Tagged
Polymer
•TRASAR Control
•
Control
Tagged Polymer
•
Monitor
Nalco Scale Index
•TRASAR Control
•Control Tagged Polymer
•
Control
Nalco Scale Index
Conductivity
Step 1
Step 2
Steps 3 & 4
TRASAR
Tagged Polymer
0
100
ppm
Before -
Make sure to baseline your system performance data before initiating the 4-Step process.
By doing this you will be able to clearly see the added value provided by 3D TRASAR Scale
Control.
Step 1
TRASAR Control Mode
-
The purpose of this step is to gradually replace any old
UNTAGGED polymer product with the new, TAGGED polymer product. The TRASAR Product is
controlled based on TRASAR while the Tagged Polymer Product is slaved to the TRASAR Product.
Blowdown is controlled based on conductivity during this period.
Step 2
3D TRASAR Scale Blowdown Monitoring Mode
- In this step the 3D TRASAR controller
learns the typical rate of polymer consumption needed to calculate NSI. The Tagged Polymer
product will now be controlled based on the setpoint recommended by the 3D TRASAR Optimizer.
The TRASAR product will still be under TRASAR control mode. Blowdown is controlled at the same
conductivity setpoint, while in Scale Monitoring mode with no blowdown setpoint adjustments.
Step 3
3D TRASAR Scale Blowdown Control Mode
- This step switches the blowdown control
from conductivity-based to 3D TRASAR Scale Control. The controller will now respond to high
system scale stresses by reducing the blowdown setpoint.
Step 4
Advanced 3D TRASAR Scale Blowdown Control Mode
- This step adds to 3D TRASAR
Scale Blowdown Control the feature of increasing the blowdown setpoint during low scale stress
conditions to maximize system water and chemical efficiencies.