Application Note - Oxygen Monitoring in ATEX Environments Using Optical Sensors

RIERA NADEU is a global leader in industrial separation and drying technology that offers high-quality, customizable, and turnkey solutions for the chemical, pharmaceutical, and oil & gas industries. With a focus on innovation, the company continuously implements cutting-edge technology to improve efficiency and reliability.

A key challenge for their ATEX-rated centrifuges was the limitations of their previous amperometric oxygen sensors, including high maintenance requirements, a bulky design, and a short lifespan. To address these challenges, RIERA NADEU transitioned to Hamilton’s VisiFerm mA Optical Oxygen Sensors, resulting in significant process improvements. This application note outlines the benefits and impact of this transition within their ATEX (explosive atmospheres) applications.

RIERA NADEU initially relied on amperometric oxygen sensors with separate transmitters from another vendor to monitor oxygen concentration in the venting zones of their ATEX-rated centrifuges. For these applications, they required an ATEX-certified sensor technology capable of measuring very low levels of oxygen. 

The company transitioned to Hamilton’s VisiFerm mA Optical Sensors installed with the FlexiFit TC 1.5", streamlining integration by eliminating the external transmitter while maintaining 4-20mA signal compatibility. The VisiFerm mA’s compact design (Figure 3) also simplified installation and resolved sensor placement concerns, while its integrated Arc features, combined with Bluetooth communication to ArcAir software on their mobile devices, streamlined sensor maintenance. This shift from a bulky, high-maintenance amperometric system to an integrated, stable optical solution addressed limitations like electrolyte replacement and short lifespans, and significantly reduced calibration efforts by eradicating lengthy polarization protocols. 

Some demanding applications require a sensor manufactured from an extremely robust and corrosion-resistant material that could withstand corrosive chemicals and acids. To meet these criteria, Hamilton also produced an OEM VisiFerm mA Sensor with HASTELLOY. The H4 kit, which is suitable for chemical-intense industries, improved the sensor lifetime while minimizing maintenance such as calibration frequency. Ultimately, the VisiFerm mA delivered consistently accurate oxygen control, ensuring lasting precision and enhanced safety in demanding ATEX environments.

The successful implementation of the VisiFerm mA Optical Sensor significantly improved oxygen control within RIERA NADEU’s equipment, leading to more efficient, safer, and cost-effective operations. Beyond the operational improvements, Hamilton’s OEM expertise provided RIERA NADEU with application-specific modifications, ensuring optimal compatibility. Building on this success, RIERA NADEU now plans to extend the use of VisiFerm mA Optical Sensors to other equipment, including dryers in ATEX environments. Companies considering this transition can expect lower operational costs, improved measurement reliability and accuracy, and seamless integration into existing systems.

Authors

David Mansilla

Technical Manager

Pol Cirera

Marketing Assistant