Responsible Lithium Hydroxide Production
Lithium hydroxide production at our planned Carolina Lithium project is being designed to use the innovative Metso:Outotec alkaline pressure-leaching technology for refining spodumene concentrate to battery-grade lithium.
Using soda ash, lime, and steam, this process eliminates the use of acid-roasting for a sodium-sulfate free method for producing lithium hydroxide. Throughout the stages of conversion in the process design, various streams are recycled, and multiple natural gas burning elements that are typically included in traditional conversion technologies are removed from the drying process.
We believe the entire conversion method is environmentally sustainable and safer for employees and the community than conventional spodumene-to-hydroxide conversion processes.
Why is pressure leach conversion more environmentally friendly than traditional
acid roasting?
The pressure leach process eliminates the production of sodium sulfate as a byproduct of manufacturing lithium hydroxide. While sodium sulfate has some commercial applications, its use has greatly declined in the U.S. over the past several decades, and therefore it is considered a waste stream that would require specialized waste handling.
Eliminating large volumes of concentrated sulfuric acid in our process makes it safer for our employees. Pressure leaching also has fewer air emissions than acid roasting.
Further, the sandlike tailings from our process would be inert and slightly alkaline, whereas those from acid roasting can have residual sulfuric acid associated with them, requiring treatment before they can be disposed. Our tailings would have possible commercial applications in road construction, concrete, or similar applications, and we are evaluating this potential.