Sustainability Examples

Managing
Spent Potlining

Issues: Community Development, Well-being, Environmental Releases
Stakeholders: NGOs, Government, Communities
Region: North America

The Quebec aluminum industry alone generates some 50,000 tonnes of spent potlining each year, half of which comes from Alcan.

Alcan's Arvida Research and Development Centre in Quebec, Canada, developed and tested a spent potlining treatment process known as the Low Caustic Leaching and Liming process (LCLL). The process, which combines a series of processes already used by Alcan, treats the waste material efficiently while also recycling it by creating usable by-products.

In 2002, with several options now available for treating SPL, the Primary Metal group formed a multi-disciplinary team to evaluate potlining management practices in the aluminum industry around the world. The team selected LCLL and, in October 2003, Alcan announced its intent to construct a spent potlining treatment facility based on our in-house developed process.

With the new 80,000 tonne-per-year facility, Alcan will create some 50 direct jobs in the region. At the end of 2003, work began on obtaining the necessary government authorizations and laying the groundwork for public consultations and an awareness campaign.

In Brazil, where a smaller amount of SPL is generated, a new initiative was introduced in 2003 where the waste material is used in the cement industry. This environmentally stable solution has resulted in the processing of some 15,000 tonnes of SPL generated between 1999-2003, depleting the SPL stockpile to zero.

The treatment of SPL is a strong example of Alcan's voluntary commitment to sustainability. The new SPL Treatment Centre in Quebec also now provides a global solution that can be applied industry-wide. It eliminates the need to store a potentially hazardous material, removes a local concern wherever SPL is stored, and has improved employment opportunities in the community.