Automated dosing driven by real-time flow measurement and analytical sensor feedback — chemical added in proportion to demand, so the dose tracks the load instead of a fixed guess.
Flow and water quality both vary through the day, so a fixed pump setting always over- or under-doses. Flow-proportional control paces the dose to measured flow, and adds analyser trim — pH, ORP, residual chlorine or turbidity — to correct for changing quality. The result is chemical added in proportion to real demand: tighter compliance, lower reagent cost and a plant that looks after itself.
Control Strategies We Apply
We match the control strategy to the duty. Flow-pacing alone suits a stable feed; flow-pacing plus residual or pH trim (a compound loop) suits a variable one; full feedback on an analyser suits a tight target. Each is built on properly selected, properly sited instruments and tuned loops, and integrates with the site SCADA for logging, alarms and remote oversight.
Pump output scaled directly to the measured process flow for the bulk of the dose.
Analyser feedback fine-tunes the flow-paced dose for changing water quality.
Feed-forward flow plus feedback trim combined for stable, demand-based dosing.
Set points, trends, alarms and remote control through the site control system.
Where Control Loops Go Wrong
Closed-loop dosing only works if the measurement is sound and the loop is tuned. These are the pitfalls we design around.
Mixing and reaction delays cause hunting unless the loop is tuned for the dead time.
Drifting or fouled analysers mislead the loop — siting, cleaning and validation matter.
PID tuning balances fast correction against overshoot for a steady dose.
How Flow-Proportional Control Works
A flow meter provides the real-time signal that paces the bulk dose.
Pump output is scaled to flow so the dose tracks load instantly.
An analyser — pH, ORP, residual or turbidity — reads the treated result.
PID tuning for the process dead time gives stable, hunting-free control.
Choosing the right loop
| Strategy | Inputs | Holds target when | Typical use |
|---|---|---|---|
| Manual / fixed | None | Flow & quality steady | Trim / pilot only |
| Flow-paced | Flow | Quality steady, flow varies | Coagulant on stable feed |
| Feedback | Analyser | Flow steady, quality varies | pH correction |
| Compound loop | Flow + analyser | Both vary | Most full-scale plants |
Plant and tools for this duty
Why Choose Reynolds & Bauhm
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Our engineers size storage, pumps, injection, control and containment to your measured duty — then build and commission it.
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