pH measurements in the bleach towers have historically been among the most difficult applications in the pulp mill. The high pulp consistency of the process stream and harsh bleaching chemicals degrade the performance of most general purpose sensors. Those sensors tend to require cleaning regularly and frequently, and they may not be able to withstand the strongly oxidizing environment. Deposits can be a major problem in all steam boilers, in the pulp and paper mill steam boilers, any accumulation of material on internal surfaces may result in overheating and/or corrosion which can result in a shut down.
The TUpH™ large area reference junction for minimum maintenance requirements: The reference junction provides an electrical connection between the reference electrode and the sample, and helps maintain a stable reference potential, regardless of the change in sample pH. The TUpH Model 398R pH and ORP sensors are well-suited for this kind of application. The wide-area junction provides resistance to coating, while the patented helical pathway prevents process intrusion into the inner reference chamber. Construction materials of Tefzel and Kalrez are used to withstand the strongly oxidizing environment.