Online pH measurement
|
pH loop
For online measurements, we talk about a so-called pH measurement loop, or pH loop. A pH loop is made up of three components, the pH electrode, the pH transmitter, and a cable to connect the electrode to the transmitter. The reason we use the term transmitter, and not a pH meter, is that a transmitter has some form of a communication interface which can transmit data to a control system or a computer.
Chemically aggressive environment
To pick and install the right equipment to get a trouble-free operation is not always an easy task for process pH control systems. Industrial pH probes lead a hard life. In chemical processes, they may have to withstand strong acidic or caustic solutions under high temperatures. However, not only the electrode but also the transmitter, the cables and connectors have, in many times, to withstand an aggressive environment. The aggressive nature of many process pH applications means that periodic maintenance and checking are required to ensure accurate and trouble-free measurements.
Process pH measurement considerations
Regardless of whether a pH measurement is done in a laboratory or in a process plant, it is important to understand how the measurement is made, how to calibrate and how to recognize and avoid common problems. How the electrode and the pH meter works and how to maintain and calibrate the pH electrode is already described on this web site. However, there are some specific things regarding online pH measurements that we need to address:
• Installation of pH electrode holders
• How to predict the calibration interval for your process pH electrode?
• Troubleshooting pH measurement loops
• Ground loop problems are very common in industrial pH measurement systems.
• Differential pH sensors may provide a solution if all else fails.
• To make sure your pH sensor is working properly you need to use intelligent sensors.
Share your point of view with others!
Take the opportunity to share your knowledge and experiences with others.
Please, use the below form to publish your contribution about the subject
"online pH measurement".
Before your page is published, it will be reviewed to make sure it applies to the submission guidelines for this website.
Don't forget to read what others have written, maybe you have a comment to add.
to: Homepage