1. IC Controls Quality Water Solutions for pH www.iccontrols.com pH / ORP Conductivity Dissolved Oxygen Chlorine Standards R1.0 © 2004 IC CONTROLS Concerns in pH # 8: Clogging of the Electrode Tip CONTROLS

2. IC Controls Quality Water Solutions for pH www.iccontrols.com pH / ORP Conductivity Dissolved Oxygen Chlorine Standards R1.0 © 2004 IC CONTROLS PROBLEM One of the major concerns in pulp applications is clogging of the electrode tip. Pulp fibres get caught in the area around the glass, clogging the electrode. Once clogged with pulp fibres the reference and glass to no longer have contact with the process and thus, inaccurate pH measurements result.

3. IC Controls Quality Water Solutions for pH www.iccontrols.com pH / ORP Conductivity Dissolved Oxygen Chlorine Standards R1.0 © 2004 IC CONTROLS Solution There are two modifications that can be made to the electrode to reduce clogging. Use Flat Glass or use a Pulp Modified Tip.

4. IC Controls Quality Water Solutions for pH www.iccontrols.com pH / ORP Conductivity Dissolved Oxygen Chlorine Standards R1.0 © 2004 IC CONTROLS pH Tip Configurations

5. IC Controls Quality Water Solutions for pH www.iccontrols.com pH / ORP Conductivity Dissolved Oxygen Chlorine Standards R1.0 © 2004 IC CONTROLS Flat Glass Flat surface reduces crevices to clog Flat surface minimizes direct impact on glass Flat surface is parallel to flow - does not contact liquid sample as well Flat glass has 90º angle which can break in thermal stress applications Pulp Modified Tip Domed Glass better in thermal stress applications Tip Protection from shearing of dense stock Dewatering on the electrode edge for better pH response Flow over surface on domed glass provides more accurate pH results pH Tip Configurations

6. IC Controls Quality Water Solutions for pH www.iccontrols.com pH / ORP Conductivity Dissolved Oxygen Chlorine Standards R1.0 © 2004 IC CONTROLS Better Electrode Protection Less Clogging Thermal Stress Protection Better Response and Longevity Proven Technology Superior Design Better Results Pulp Modified Tip