Lessons from aluminum and magnesium scraps fires and explosions: Case studies of metal recycling industry

Metal recycling industry offers a pathway for promoting resource reuse and waste mitigation. Particularly, aluminum and magnesium alloys, which are handled efficiently, have been adopted in various sectors and recycled. Despite the advantages of these materials, recycling these products introduces the risk of fires and explosions during the recycling process owing to their physical and chemical properties. Aluminum and magnesium are notable water-reactive and combustible metals. Thus, with the internal and external hazards, such as water and chemical reactions, the aluminum and magnesium in the recycling plants can ignite violently, causing disastrous consequences. Thus, this study aims to draw lessons to improve the risk and safety management capacity of metal recycling plants in South Korea by investigating four cases of fire and explosion in magnesium and aluminum recycling plants. The lessons identified are as follows: set up regulations/guidelines to undertake measures based on the hazardous materials from the recycling process and possible reactions; consider the probability of extreme events caused by external hazards based on risk analysis and assessment; prepare safety and preventive equipment considering the specific environmental conditions of the metal recycling plants; plan resources required for appropriate response; arrange safeguards to avoid possible damage; and finally, discern the mechanism of aluminum and magnesium fire. •Scrap metals, i.e., aluminum and magnesium, are not classified as hazardous waste materials in many countries.•The risk of fire and explosion at the metal recycling plants is increased due to various external hazards.•The latest fires and explosions at the metal recycling plants were investigated and studied in the context of South Korea.•The lessons from the cases will be valuable to advance the practices for safety management at the metal recycling plants.