Alkaline Ph Measurement Errors in Reactive Dye Bath Operations
Uncorrected sodium ion interference and junction drift in high-alkaline reactive dye baths distort pH readings by up to 0.6 units, causing dye hydrolysis and batch off-shade failures.
Ph Probe Drift
Electrode Instability
Continuous monitor probes in wet finishing lines can experience a gradual shift in their baseline readings over time. This ph probe drift leads to incorrect measurement of acidity in bleaching and scouring liquors. The shift is often caused by the slow dilution of the reference electrolyte solution inside the electrode.
Continuous monitoring prevents errors in chemical dosing. This measurement error can result in poor fabric dye uptake if left uncorrected.
Temperature Influence
High-temperature dyeing cycles accelerate the leakage of the reference solution and stress the glass membrane. To minimize ph probe drift, mills must use double-junction electrodes filled with high-temperature gel. Process temperatures often exceed eighty degrees Celsius in polyester dyeing.
Production Failure
Scouring raw cotton requires a highly alkaline bath to remove natural waxes and pectin. If ph probe drift causes the system to read a lower pH than is actually present, excess sodium hydroxide may be added to the bath. This over-dosing can degrade the natural cellulose fibers and weaken the yarn.
Maintenance Protocol
Operators must perform manual offset corrections using portable reference meters to catch sensor drift between scheduled calibrations. Re-calibrating the probe every twenty-four hours maintains process control. If the drift persists, the reference electrolyte must be replenished or the probe replaced.