Lindner cites results from its fire prevention system

Austria-based equipment maker Lindner-Recyclingtech GmbH says a continuous, process-related monitoring system it has developed to scan the surface temperature of materials on moving conveyors “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) contains optical sensors designed to constantly monitor the temperature of material on conveyor belts, and can automatically trigger a water sprinkling system to cool overheated particles in the material stream. The early detection of hot spots means “most hazards are identified at the start of a thermal reaction, keeping the required amount of water low,” according to Lindner.

Mayer Recycling GmbH, Upper Styria, Austria, has been using the system and collecting data since mid-2019. That data “clearly demonstrate the benefits of this sophisticated technology,” says Lindner.

On average, more than 350 overheated particles in the material stream are detected per month at Mayer. Of these, approximately 10 percent were deemed too hot for further processing, triggered the alarm and were manually removed.

Of the removed materials, around 70 percent were batteries that already were undergoing a chemical reaction. The remaining system triggers were “coolable materials such as metal particles that got too hot after shredding,” according to Lindner.

Lindner says it developed FPS to address the growing risk of fires, which it calls “one of the most pressing recent issues in the mechanical processing and conversion of waste into SRF.” This risk is caused predominantly by “a constantly increasing number of lithium batteries” in waste and recycling streams, says the firm.

Lithium-ion batteries, found most commonly in mobile phones but also in any number of small appliances or communication devices, have grown in popularity. They often are discarded in materials streams that end up in waste transfer stations, SRF plants, electronics recycling and material recovery facilities (MRFs), and as automobile shredder feedstock.

The widespread presence of the batteries means “the risk of fire [has] increased exponentially during mechanical processing” of materials at all these types of facilities, says Lindner.