Battery Recycling Dust Collection

Battery recycling is much needed to keep toxic and hazardous materials out of landfills and enable recovery and reuse of valuable materials such as cobalt, nickel and lithium. As demand for Li-ion batteries grows, it is increasingly difficult and expensive to recover raw materials for battery production. Battery recycling reduces demand for the heavy metals and rare earth elements used for production of modern batteries. It also keeps hazardous materials such as lead, antimony and cobalt from leaching out of landfills and polluting soil and waterways. In many jurisdictions, proper disposal and recycling of batteries (including both consumer and industrial batteries) is required by law. 

The specific steps in the battery recycling market can vary depending on the type of battery being recycled and the materials being recovered. Steps may include:

• Sorting: Once collected, batteries are sorted into different types based on their chemistry, size, and other factors.
• Breaking and crushing: The batteries are then broken or crushed to release the valuable metals and other materials inside.
• Hydrometallurgical processing: The metals are extracted using a combination of chemical and physical processes, which can vary depending on the specific battery chemistry and materials being recovered.
• Refining and purification: The recovered materials are then refined and purified to produce high-quality materials that can be used in new battery production or other applications.

• Worker health risks: Batteries contain a variety of hazardous chemicals, such as lithium, cobalt, lead, cadmium, mercury, and acids, which can be released during the recycling process. Exposure to these chemicals can cause respiratory problems, skin irritation, and other health effects. The crushing and grinding of batteries during the recycling process can generate dust and other airborne particles, which can be inhaled by workers and cause respiratory problems. The specific health impacts will depend on the type of dust and the level of exposure. Some materials, such as lead, can have serious impacts on the brain and nervous system, kidneys, liver and bones; workers in battery recycling facilities may, if not careful, carry enough lead dust home to put families and children at risk for lead poisoning. Recycling Li-ion batteries may expose workers to heavy metals such as cobalt, nickel and lithium; these metals are associated with a range of health effects, including neurological problems, kidney damage, and reproductive problems. Workers may also be at risk for chemical burns and lung damage from inhaling acids and solvents released in battery demolition.
• Fire and explosion risks: Dust produced during battery recycling may be combustible. Carbon black, graphite, lithium salts and silicon powder, among other battery materials, are highly combustible under the right circumstances. Plastic dust created when crushing battery casings for Li-ion batteries can also be explosive. If clouds of dust are allowed to form within an enclosure (including the dust collection system itself), a spark or ignition source can easily set off a dangerous combustible dust explosion. Batteries themselves create a ready ignition source; lithium-ion batteries, in particular, create a significant fire or explosion risk when damaged. Download the Visual Guide to Combustible Dust.

• Worker health and safety: Battery recyclers in the US must have systems in place to ensure that workers are not exposed to dangerous dust, fumes and chemicals at levels above the Permissible Exposure Limits (PELs) for respirable materials set by OSHA. OSHA publishes these exposure limits in their Annotated PEL Tables. If the PEL is not met, employers may be subject to fines or sanctions. Manufacturers should also be aware of Recommended Exposure Limits (RELs) from the National Institute of Occupational Safety and Health (NIOSH) and Threshold Value Limits (TLVs) from the American Conference of Governmental Industrial Hygienists (ACGIH); these guidelines may be lower than the OSHA-required PEL. While not legally required, many employers may wish to aim for more stringent air quality standards set by these bodies.
• Environmental protection: Battery recycling facilities are subject to environmental regulations related to air and water pollution, waste management, and hazardous materials handling, including the Clean Air Act, Clean Water Act, and Resource Conservation and Recovery Act (RCRA). These regulations may require the use of dust collection and air filtration systems, wastewater treatment systems, and other environmental controls to prevent or reduce emissions into air, water or soil. The regulations govern how materials are handled and stored, how waste material is disposed of (including particulate collected in the dust collection system), and how much material may be emitted into the atmosphere.
• Fire and explosion protection: Battery recyclers must take steps to minimize the risk of a dangerous fire or explosion in their recycling facility. Combustible dusts are regulated under OSHA’s Combustible Dust National Emphasis Program (NEP). Manufacturers are also responsible for following NFPA standards for handling combustible materials, including standards for dust control and dust collection system design; these may include the the Standard on the Fundamentals of Combustible Dust (NFPA 652), the Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids (NFPA 654), the Standard for Combustible Metals (NFPA 484), and guidelines for dust collection system design and explosion venting outlined in NFPA 68, and NFPA 69.

• Dust characteristics: Different battery recycling applications may produce a variety of different dust and fume types, including abrasive dust, fine and ultrafine dust (including nanomaterials used in battery production), and caustic fumes and gases. This requires a heavy-duty dust collection system that is capable of withstanding coarse, abrasive dust and exposure to caustic vapors. Abrasive-resistant coatings may be required for ductwork and the dust collection filter cabinet. Filter selection is also important to ensure the efficient collection of both heavy and fine materials (including high-static materials) as well as vapors and gases released during recycling. A progressive filtration strategy may be needed, including heavy-duty cartridge filters to collect large volumes of heavy dust and a combination of HEPA and activated carbon after-filters. 
• Highly toxic materials: Many battery materials, such as cobalt and lead, are highly toxic when inhaled and have very low permissible exposure limits. The system must be designed to ensure that PELs for all controlled materials are met. Air quality testing and worker exposure testing are recommended where workers may be exposed to highly toxic material such as lead or mercury. Source capture systems should be used where possible to ensure efficient collection of dust from crushing and recycling processes. In some cases, a backup ambient air filtration or ventilation system will be required to collect dust and fume that escapes the primary source capture system. If PELs cannot be met with engineering controls alone, PPE may be required for workers directly exposed to toxic materials.
• Combustibility and explosiveness: Battery recycling facilities can pose combustion risks due to the flammable and reactive nature of the materials being handled. Li-ion battery waste, in particular, creates an explosion risk; Li-ion batteries can catch on fire or explode when damaged, which can create a chain reaction if combustible dusts are present. An NFPA-compliant dust collection system designed to handle combustible dust safely and reduce the risk of fires or explosions is typically required for duct collection in battery manufacturing facilities.