What is pH?
One of the most widely used water measurements, pH is a measure of acidity and alkalinity, or caustic and base, respectively, of a solution. It is expressed typically on a numeric scale of 0-14. A value of 7 represents neutrality. Lower numbers indicate increasing acidity and higher numbers increasing alkalinity. Each unit of change represents a tenfold change in acidity or alkalinity which corresponds to the negative logarithm of the hydrogen-ion concentration or hydrogen-ion activity.
How is pH Measured?
When pH measurements are critical for controlling processes, an electrochemical pH sensor is most commonly used. The sensor is a normally combination type which contains a measuring electrode and reference electrode. The measuring cell detects changes in pH value and the reference provides a stable signal for comparison. A high impedance device known as a pH meter is used to display the millivolt signal as pH units.
How are pH Measurements Used?
pH measurements are widely used to control processes, ensure product quality or safety.
- pH neutralization of effluent in industrial manufacturing environments
- Cooling towers and boiler control
- Environmental monitoring
- Odor scrubbers
- Food and beverage quality control and safety
- Upstream protection of filtration membranes
- Water pre-treatment for manufacturing processes
- Swimming pool control
- Pulp and paper manufacturing
- Pharmaceutical research & development and manufacturing
- Blood-gas analysis in medical devices