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Recycling
The continuous, process-related monitoring of surface temperature at several relevant points has proven to be highly successful in combatting potential fire hazards and actively improving safety in facilities that produce solid recovered fuels (SRF). Lindner’s Fire Prevention System (FPS) therefore sports optical sensors that constantly monitor the temperature on the conveyor belts and trigger a water sprinkling system to cool overheated particles in the material stream automatically. Thanks to the very early detection of these particles, most hazards are identified at the start of a thermal reaction keeping the required amount of water low.
Furthermore each unit has its own control sensor detecting objects that cannot be cooled, such as lithium-ion batteries where the thermal runaway has already been initiated. This triggers an alarm, stopping the conveyor belt under an active cooling nozzle so the hazard can be manually removed. Depending on the application the threshold value can be chosen freely. To counteract even a delayed reaction of the energy cells, it’s possible to install as many sensor pairs as needed depending on the size of the facility.
Lindner’s FPS is designed as a space-saving plug&go solution to facilitate the integration of the system in existing facilities. Its heated box version also makes it perfect for cold environments.
Best Practice Example – Mayer Recycling GmbH
One of the first companies to try out this innovative solution was Mayer Recycling GmbH in Upper Styria, Austria. The data collected since mid-2019 clearly demonstrates the benefits of this sophisticated technology. Figure 2 shows the temperature on the conveyor belt during typical SRF production. On average, over 350 overheated particles in the material stream are detected per month. Of these, approximately 10% were still too hot for further processing, triggered the alarm and were manually removed. Of the removed materials, around 70% were batteries that were already undergoing a chemical reaction. The remaining system triggers were coolable materials such as metal particles that got too hot after shredding.
To summarise, the data collected clearly shows that Lindner’s FPS substantially reduces the fire risk in SRF production facilities.
MRF’S
Cooling after the first sensor was triggered
Lindner’s Fire Prevention System (FPS) sensor instantly detects overheated particles after the first shredding unit
Literature Review
Lorber, K., R. Sarc & R. Pomberger (2010). Austrian
experiences in the use of different wastes as solid recovered fuels (SRF) and possible application problems. Turkish-German Waste Days 2010 – Resource protection through the implementation of sustainable waste management. pp. 327-348 (in German)
VOEB Association of Austrian Waste Management Companies (2019). Press release: 1.4 million highly inflammable lithium batteries end up in the general waste collection every year, https://www.voeb.at/service/voeb-blog/detail/show- article/14-millionen-brandgefaehrliche-lithiumbatterien- landen-jaehrlich-im-restmuell/, (accessed: 09 July 2020) (in German)
Austrian Chamber of Commerce, Waste Management and Resource Management Association (2019). Careful handling and correct disposal: Why lithium batteries and lithium-ion rechargeable batteries should never be disposed of in household waste, https://lithium-info.at/ (accessed: 09 July 2020) (in German)
www.hub-4.com Sept/October 2020 - Issue 64
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