Controller — Acids
30+ years spec experience. Send James the process data and get a real answer — not a catalog page.
Request a Spec Review →Named chemicals
LibertyCES has documented Controller in Acids service, including Sulfuric Acid. Documented models include GF Signet controller. Compatibility depends on exact concentration, temperature and duty cycle, so confirm with a free spec review.
Notes from the vendor documentation
Chrome reduction: pH lowered to 2.0-2.5 via acid dosing, ORP setpoint -300mV, explicit SO2 gas-release hazard if overdosed.
Materials documented for this service
- N/A
Products cited for this service
Real Specifications
| Spec | Value | Source document |
|---|---|---|
| Chrome reduction optimum pH range | pH 2.0-2.5 | GF Piping Systems — Application Solutions Made Easy: Chemical Process Industry |
| Chrome reduction minimum detention time | 15 minutes | GF Piping Systems — Application Solutions Made Easy: Chemical Process Industry |
| Chrome reduction ORP setpoint | -300mV (-400mV max) | GF Piping Systems — Application Solutions Made Easy: Chemical Process Industry |
| Cyanide destruction stage 2 (sulfuric acid) detention time | Up to 4 hours (modern systems) | GF Piping Systems — Application Solutions Made Easy: Chemical Process Industry |
| Cyanide destruction stage 1 oxidation target | Below 0.1 ppm | GF Piping Systems — Application Solutions Made Easy: Chemical Process Industry |
GF Signet warns explicitly that lowering pH further than the 2.0-2.5 optimum on chrome reduction risks releasing hazardous sulfur dioxide gas — the reaction only needs to reach pH 3.0 before it slows significantly, so overshooting low doesn't buy faster reduction, it buys a gas hazard.
Chrome reduction is regulatorily strict for a reason — hexavalent chromium is roughly a thousand times more toxic than trivalent chromium per GF Signet's own literature, and it won't form a settleable hydroxide precipitate until it's reduced. Getting the pH/ORP control loop right (2.0-2.5 pH, -300mV ORP, 15-minute minimum detention) is the difference between a compliant discharge and a violation, which is why Liberty CES treats this controller spec as safety-critical rather than a tuning nicety.
Every material and product claim on this page traces to real, vendor-published documentation on file with LibertyCES. Chemical compatibility depends on exact concentration, temperature, and duty cycle — confirm current specifications with the manufacturer and request a spec review before final specification.
FAQ
Can Controller handle Acids?
Chrome reduction: pH lowered to 2.0-2.5 via acid dosing, ORP setpoint -300mV, explicit SO2 gas-release hazard if overdosed.
What wetted materials should Controller use in Acids service?
Materials documented for this service: N/A. Compatibility depends on exact concentration, temperature and duty cycle, so confirm with a spec review before final specification.
Which Acids chemicals does this cover?
Named chemicals in this documentation: Sulfuric Acid (chrome reduction/cyanide destruction stage 2).
Which Controller models are documented for Acids?
Documented examples include GF Signet controller.
Ready to buy or need a fast answer? Call, text, or email James directly — (559) 395-5500 · [email protected].
Send James your spec
Fluid, concentration, temperature, flow or volume, and where it goes. James replies with a real answer, not a catalog page.
Reviewed by James Riggins, 30+ years specifying water and chemical process equipment · Updated