Pyrometallurgical Recycling Process: High-Temperature Recovery with Proven Scale
The pyrometallurgical recycling process represents the oldest and most industrially proven approach to battery recycling, using high-temperature smelting to extract valuable metals. This process achieves 60-80% recovery of critical materials . The Umicore process is a prime example, involving high-temperature smelting in a vertically mounted, preheated furnace where material is heated to 300°C for gas removal, followed by plastic pyrolysis at 700°C and smelting with oxygen-rich air to obtain a nickel-copper-cobalt alloy, with lithium captured in slag .
Pyrometallurgy is gaining traction as technological advancements improve its efficiency, making it more competitive [citation:MRFR]. The process is characterized by its ability to handle a wide range of materials and produce high-quality metal outputs [citation:MRFR]. Research has demonstrated that a temperature of 800°C fully reduces Co and Ni oxides to their metallic forms, enabling effective recovery . The push for circular economy initiatives and resource security are significant drivers for the adoption of these technologies [citation:MRFR].
However, the process faces challenges. While pyrometallurgy reduces the need for chemical handling, it incurs higher energy costs and environmental impacts due to emissions . The base metals present in the feed, particularly iron, enhance the recovery process in the slag but also increase complexity. The recovery of lithium is a challenge as it becomes locked in the slag and requires further processing, such as leaching with water at around 80°C for 2 hours in CO2 to dissolve lithium carbonate . Despite these challenges, pyrometallurgy remains a cornerstone of the recycling industry.
