Early warning response: FLIR’s thermal imaging cameras

FLIR’s thermal imaging cameras have been helping dynamic waste facilities in Australia and around the globe to reduce their fire risks. 

Swedish energy company Jönköping Energi, based in Torsvik, has been transforming waste into district heating – a common practice in the Scandinavian country.

The critical issue for any waste operator is detecting fire risks as efficiently and quickly as possible to control fires and prevent them from spreading. 

Its of particular importance for sites maximising uptime at high volumes, as Jönköping Energi transforms up to 145,150 tonnes of waste per year, or 18 tonnes per hour, into heat and electricity. 

The district heating is enough to power 25,000 households and has been up and running since 2006. It provides about 90 per cent of district heating demand and 20 per cent of electricity used in the surrounding area. 

According to Magnus Olsson, Plant Manager at Jönköping Energi Torsvik, preventing and controlling fires in the waste bunker is not only a matter of safety, but also of economics.

“We have trucks coming in bringing in waste from the surrounding area, but also from different places in Europe. This waste is then dumped in a waste bunker and is mixed by means of automatic cranes, waiting to be transported into the boiler,” Magnus says.

These waste piles can be a dangerous mix. 

“Spontaneous combustion from biological products or other heat sources is a continuous threat and something that we need to keep an eye on 24/7,” he says.

Aside from the environmental consequences and obvious safety risks for people at the plant, a fire outbreak in a waste bunker can be a costly affair. 

“If a fire should break out, we need to shut down the plant immediately. These shutdowns cost us quite a lot of money, up to half a million Swedish Crowns a day. That’s why it is important to have a reliable early warning system that detects fires as soon as they originate,” he says.

Jönköping Energi published a tender in 2016 for the implementation of an early warning fire detection system. The tender was awarded to the Linköping-based company Termisk Systemteknik, a distributor of FLIR thermal imaging cameras and provider of fire detection systems with FLIR cameras since 2010. 

FLIR and equipment supplier Industrial Monitoring Control have worked with largest operators in the Australian waste and recycling industry to develop off-the-shelf early fire detection solutions for landfills, transfer stations, materials recovery facilities and recycling sites.

Thermal imaging cameras are now a widely accepted tool to detect fires and potential fire hazards at the critical early stages. Permanently installed cameras, operating in harmony with conventional detectors, offer a range of significant benefits over standard technologies. These include the ability to see heat build up before a fire can start, as well as seeing through airborne dust and particulates that can impede or cause false alarms from other detector types. This is because thermal imaging cameras capture thermal radiation in the long wave infrared portion of the electromagnetic spectrum, far beyond what our eyes can see. 

It gives operators the ability to stop a fire from occurring or be able to lessen its impact, making the site safer and reducing business costs. 

As waste management sites can be dynamic with a number of moving vehicles and infrastructure, camera mounting locations must not be impeded by equipment or the camera will be ineffective. 

On a landfill site, for example, FLIR Systems ThermoVision GasFindIR can be used to identify a range of volatile organic compound gases, including methane. Where gases are captured for energy, the cameras detect leaks in pipework. They can also identify vegetation health where vegetated soil covers are used to reduce the drainage of rain water into waste using water balance mechanisms rather than traditional barriers. 

Claes Nelsson, Product Manager at Termisk Systemteknik AB, says the Torsvik plant was already working with an aspiration-based smoke detection system. The system pulls in air from the environment, which is then analysed for the presence of smoke. 

He says that for fire detection, thermal imaging is superior, as operators sense the temperature of the material and are not dependant on smoke or temperature spreading in the room.

The fire detection system at Torsvik consists of two FLIR A615 cameras in protective housings mounted on pan tilt systems, one at each end of the bunker. They are controlled via the dedicated TST Fire software
from Termisk. 

When a hot spot is detected by one of the two cameras, the other is directed at the hot spot. The TST Fire software then calculates the accurate coordinates of the hot spot, based on the combined thermal images, and an alarm is generated. Upon activation in the waste bunker control room, the water canon is directed at the detected hot spot and the fire is extinguished. Termisk’s TST Fire software uses thermal imaging cameras from FLIR to monitor and analyse assets for hot spots. 

Claes says that thanks to the high resolution of the two FLIR A615 cameras – 640 by 480 pixels – the entire bunker can be monitored in high detail, enabling control room operators to detect really small hot spots. 

“The FLIR A615 is one of our preferred FLIR cameras for this type of application,” Claes says.