pH monitoring system with online calibration capability

Paul Boughton

Specialist electrochemical sensor manufacturer Analytical Technology announces that its innovative new Q45P pH monitoring system is capable of online calibration, speeding up the production process and optimising pH readings.

The new Q45P system with online calibration is designed for use in all industrial and municipal applications including wastewater treatment, breweries, dairies and pharmaceutical manufacturing.

pH measurement is a critical process and is widely performed in manufacturing procedures from water and wastewater treatment to pharmaceutical production.

Traditionally, off-line calibration and maintenance methods require production to be halted while calibration and maintenance is carried out, leading to delays in production. Conventional pH sensors have an open reference system, meaning that chemicals can easily diffuse into the reference chamber as the reference element and electrolyte are in contact with the process.

Once the reference junction has been contaminated by chemicals the reference potential alters and the sensor no longer functions. Challenges with offline calibration often result in production efficiency and can lead to significant financial loss.

In order to overcome the issues associated with offline pH monitoring techniques, Analytical Technology has developed the new Q45P with a ‘lock and load’ pH system that allows the user to retract and service the probe online using the 'lock and load' technique without the need to halt the process or divert sample flows.

The Q45P pH sensor is constructed with a second glass pH electrode as the reference element. The glass reference system protects the sensor from chemical poisons that damage conventional pH sensors.

An integral preamplifier is encapsulated in the body of the sensor, which generates a low impedance signal output, ensuring stable readings and maximising the distance between sensor and analyser. Large volume, dual junction saltbridge is employed to minimise contamination of the reference solution. 

The Q45P Auto-Clean system with a self-contained compressor and air cylinder produces high pressure air to automatically remove contaminants from the surface of the sensor. The system significantly reduces maintenance and calibration time, removing the issue of false readings. The Auto-Clean feature coupled with the system’s online calibration capability maximise the sensor’s service life and lower the cost and time required for sensor maintenance.

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