Case Study

Massive pH Sensor Lifetime Improvement

Case Study

in Chemical Production

Achieve pH Sensor Lifetime Improvement
Achieve pH Sensor Lifetime Improvement

pH control is vital in many chemical production steps. In many applications though, the measurement media can make pH measurement a significant challenge. The presence of high temperatures, high pressures, and aggressive or abrasive substances, can significantly reduce pH sensor lifetime. Regular pH sensor cleaning and calibration helps, but exposes maintenance technicians to the dangerous process conditions.

The production of nitrogen-based fertilizers is one industry where pH control is very important and the conditions mean sensor lifetime is usually very short.

For a US fertilizer producer, the two-week sensor lifetime of pH sensors in their ammonium nitrate process was unacceptable. The cost of regular sensor replacement, and exposure of staff to hot and dangerous chemicals, were significant concerns.

METTLER TOLEDO installed a solution that not only significantly reduced pH measurement costs, it also minimized maintenance technician exposure to the hazardous process media.
 

The InPro 4260i is a pH sensor that tolerates harsh conditions such as ammonium nitrate production. The keys to its endurance are a solid polymer reference electrolyte that resists poisoning from contaminating substances, and an open junction instead of a diaphragm that would quickly clog in the process. The resulting longer sensor lifetime means technicians spend less time at the measurement point, and lowers sensor costs.

The second element that improved pH control for the fertilizer company is Intelligent Sensor Management (ISM) technology. ISM is a digital process analytics platform that uses the power of intelligent sensors to provide worry-free measurement points and maximum confidence in production processes.

Among its features is the ability to calibrate sensors away from the process in any convenient location. Calibration data is stored in the sensor itself, so when sensor replacement at the measurement point is required, it is a simple case of swapping the existing sensor with a pre-calibrated one. 

A year after installation of the METTLER TOLEDO pH probes, plant manager reports that sensor lifetime has extended from an average of two weeks, to twelve - a staggering 500% improvement.

Read more in the Success Story.