Customer application

A Watchful Eye for Maintenance

WAGO Automates Monitoring of High-Temperature Reactors

As part of its decarbonization efforts, Air Liquide has introduced around-the-clock monitoring at its syngas plant near Stade, Germany for a newly installed reactor. This setup ensures smooth operation and minimizes disruptions. The system, which combines thermal cameras and a WAGO IoT Gateway integrated with the plant’s control system, allows for early anomaly detection to facilitate proactive, condition-based maintenance.

Since introducing CO2 emissions trading in the European Union and Germany, many raw materials companies have taken steps to optimize processes and avoid the cost of expensive emissions certificates. While this was the intended political outcome, some companies, such as Air Liquide, have long incorporated sustainability into their corporate strategies. The Stade facility exemplifies this commitment to climate protection, and it’s now even stronger thanks to new technological investments.

The WAGO IoT Box:

  • A complete, ready-made system designed to digitize existing machines and systems with minimal effort

  • Ideal for universal use, capable of detecting currents, voltages, production cycles and system states, among other parameters

  • Connects to IT infrastructure via ETHERNET and WLAN or operates remotely using the mobile network

Investment in the Future

Successful negotiations for long-term supply contracts resulted in a fundamental retrofitting of the existing systems in Stade, one of the largest chemical production sites in Lower Saxony. Air Liquide, which specializes in industrial gases, invested nearly 40 million euros over the past year in this location. The project aimed to make syngas production more efficient and environmentally friendly. In addition to the modernization of two air separation systems, the focus quickly shifted to the partial oxidation system (POX). Previously, CO2 produced alongside hydrogen and carbon monoxide was released into the environment. The new system increases energy efficiency by approximately 15% and reduces CO2 emissions by about 15,000 tons annually, which equates to 80% of the site's direct emissions.

Air Liquide, a global leader in gases, technologies and services for industry and health, has implemented 24/7 monitoring of a new reactor at its Stade facility.

Air Liquide is very proud of this innovation, which has positively impacted the environment. “The new, 16-meter-high reactor for our partial oxidation system is particularly impressive. It weighs 58 tons, and its delivery time is more than a year. The reactor’s protection, now and in the future, was our top priority,” said Hendrik Gollek, a project engineer in Automation for Cluster Central Europe in Düsseldorf. Gollek collaborated with Air Liquide’s northern facilities technical team to ensure the project’s success.

Thermal cameras with intelligent control technology, like the WAGO PFC200, detect hazards early by identifying thermal anomalies, irrespective of environmental conditions.

Reliable Predictions Required

Operating under extreme conditions of around 30 bar and over 1000°C, the reactor is lined with firebricks to withstand this demanding environment. Over time, this lining deteriorates, but conventional methods to detect damage are costly or unreliable. Therefore, Air Liquide sought a method that could provide reliable information about the masonry without shutting down the reactor for inspections “due to a hunch” or according to a rigid schedule.

Startup procedures after a shutdown are inefficient and cost-intensive. To avoid this, the experts at Air Liquide proposed an early hazard detection system using industrial thermal imaging cameras. The Prometheus from TTS Automation was selected: the camera detects temperature anomalies and uses a combination of intelligent control technology from WAGO, like the PFC200 from the 750 Series. The system detects thermal anomalies regardless of other environmental conditions.

The new system provides warnings long before high temperatures can glow visibly through the outer metal jacket. Following such a warning, Air Liquide shuts down the process in a controlled manner. The reactor is flushed, and the inner protective layer is repaired. Thanks to the WAGO technology, the process does not have to be stopped unnecessarily for monitoring purposes, but only when a fault occurs. The second advantage is that it is possible to intervene early, i.e., if there are minor or isolated points of damage. It would require months to construct a new lining for the reactor vessel. Repairs for small faults, on the other hand, need only a few days. If the outer jacket were damaged, then a completely new reactor would be needed. The system would then be idle for an extended period, accruing associated costs and production losses.

The reactor core must be continuously monitored. To accomplish this, Air Liquide uses TTS Automation's thermal cameras with a WAGO PFC200 as an interface.

Seamless Integration into the Automation Landscape

For the engineers at Air Liquide, a decisive point in choosing a system that combines cameras and a WAGO controller lay in the future viability of the solution. “It was important to us that we not merely operate the measuring system as a stand-alone solution; instead, we wanted to integrate it into our Yokogawa process control system. This minimizes manual labor and all of its associated disadvantages, like time-consuming errors,“ says Gollek. Two groups of three cameras, arranged radially around the reactor, and one that records the vessel from above, are sufficient for uninterrupted monitoring. These seven cameras, installed in the upper, hot half of the reactor, record all relevant information for display in the control system: maximum and minimum values, divided into sectors. Fixed alarm values were defined mutually by all parties, and they only alert if the values are exceeded or undershot.

The camera software runs on the WAGO IoT Box. No translator is required, no contacts must be transferred, and no wiring is necessary. The gateway speaks the same language as the TTS camera. This interface to the control system was a key argument for integrating with the WAGO IoT Box. “The seamless integration of such devices into production within the process industry is our specialty. With the help of our solutions, Air Liquide can use all of the camera functions and process the raw data. In addition, managing and calculating anomaly data at the PLC level relieves the load on the system and allows the operators to communicate with the camera electronics directly from the control system,” explains Wolfgang Laufmann, Business Developer Smart Factory at WAGO.

System interfaces are also an important topic. “It doesn’t really matter what the user asks for, whether Modbus TCP, OPC UA, MQTT, a telecontrol protocol, or another interface to connect to a SCADA and/or Cloud system. Our toolbox is large, and we have been able to implement any special solution quickly and calmly,” says Laufmann. The advantage provided by a relatively low-effort wiring requirement also ties in here. The cameras, gateways, and process control systems are not networked via normal field instrumentation, which potentially requires additional distribution boxes; instead, they are networked via thin fiber optic cables. At Air Liquide in Stade, neither scaffolding nor the installation of field distribution boxes were necessary. “This is a cost-effective installation that WAGO offers us here,” confirms Gollek.

“But now I am pleased that so many internal and external experts have worked on the new system to save tons of CO2 and that we have simplified our maintenance by installing the monitoring cameras and WAGO IoT Box. In the best-case scenario, we will produce at full capacity until the next major overhaul in five years’ time,” laughs Gollek.