Thermal Camera Control for High-Temperature Rotary Kiln Processes

Optris Infrared Cameras Replace Costly Line Scanners

So-called line scanners, which scan over a line with a pyrometer to collect temperature information and output it in a line scanner image, are common in these rotary kiln applications. However, these line scanners are usually very cost-intensive and are nowhere near as flexible and practical as solutions with infrared cameras.
Optris relies on high-performance infrared cameras such as the PI 640i and Xi 640 to ensure effective temperature control. Both models provide high-resolution thermal monitoring to detect critical hotspots on the outer kiln wall at an early stage.

The optris PI 640i stands out with its VGA resolution of 640 x 480 pixels and an excellent thermal sensitivity of 40 mK, enabling precise detection of even the smallest temperature differences. With a wide temperature measurement range of -20 to 1500 °C, it is ideally suited for high-temperature applications. Its versatile lens options, with viewing angles ranging from 15° to 90°, allow flexible adaptation to different kiln sizes. Additionally, the high frame rate of 32 Hz, which can be increased to 125 Hz in subframe mode, ensures seamless thermal scanning of the kiln wall.

The optris Xi 640 also offers high-precision measurement with a 640 x 480 pixels resolution. Its motorized focus enables quick and easy adjustment to changing measurement conditions. With a thermal sensitivity of 80 mK and a temperature range of -20 to 900 °C, it is specifically designed for industrial high-temperature monitoring. Thanks to its compact design and GigE Ethernet or USB connectivity, it can seamlessly integrate into existing monitoring systems.

The thermal cameras are installed strategically optimally along the rotary kiln to ensure comprehensive temperature monitoring. Depending on the kiln size and the customer’s requirements, a single camera may be sufficient, or multiple devices may be distributed along the kiln. The ideal distance between the camera and the kiln is approximately 10 meters, ensuring an optimal balance between the field of view and resolution. Typically, installation is carried out using fixed mounts at a safe distance.

The camera signals are transmitted to a PC or central control unit via high-performance interfaces. Optris cameras feature, e.g., GigE Ethernet or USB connectivity, ensuring stable and low-latency signal transmission. For longer distances, a USB server can be used to extend the signal range. The transmitted data is processed in the optris PIX Connect software, enabling real-time visualization of temperature readings. Automated alarms can be triggered to warn the operator in time if a critical temperature increase is detected. Additionally, the software allows continuous recording and documentation of temperature profiles for later analysis and process optimization. The infrared cameras can also be easily integrated into existing systems and software applications.

The cameras can be equipped with protective housings to shield against weather conditions, ensuring durability and functionality in demanding environments. Air purge systems keep the optics clean, while water cooling protects the cameras from excessive heat.