An open cooling circuit loses pure water to evaporation and keeps the salts. Dosing has to follow that concentration curve continuously, or scale and biofilm take the circuit.
The Operating Reality
An open circuit cools process exchangers or chillers through a tower, feeding scale inhibitor, dispersant and biocide, with blowdown triggered on conductivity.
Why Manual Dosing Falls Short
Biofilm insulates heat transfer far more than a mineral scale layer of the same thickness, and it shields organisms from biocide. Continuous control keeps both under the threshold instead of reacting after a deposit forms.
How Automatic Chemical Dosing Fits
- Dosing tracks conductivity blowdown so inhibitor concentration follows cycles of concentration.
- Biocide feed is scheduled and alternated, with ORP feedback confirming the oxidation dose landed.
- Leak alarm within 2 seconds, dry-running protection and 316L construction suit tower-side plant rooms.
Selection Checklist
- Define the control signal first (pH, ORP, conductivity or flow-proportional) before sizing the pump.
- Size the metering pump to the lowest expected dose with margin, not to the peak dose.
- Confirm chemical compatibility of wetted parts (316L, PVC, PVDF) with every product to be fed.
- Provide containment, leak detection and dry-running protection in the dosing room design.
- Integrate the skid with PLC, DCS or remote telemetry so dose is visible in the control room.
Related Products
- Automatic Chemical Dosing System
- Automatic Condenser Tube Cleaning System (ATCS)
- Constant Pressure Water Make-up System
FAQ
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