Sustainability Examples

Reducing Air Emissions
at Rotterdam

Issues: Well-being, Environmental Releases
Stakeholders: Employees, Communities
Region: Europe

Alcan, in partnership with Hydro and Soeral, has produced prebake anodes for smelters at Aluchemie (Aluminium and Chemicals Rotterdam) in Rotterdam, Netherlands since 1964.

With seven bake furnaces, the anode production process results in emissions that include volatile hydrocarbons. Current treatment processes at the site ensure that the atmospheric releases are about 60 to 70 mg of volatile Hydrocarbons/m³ exhaust gas, which is generally below the government established limit of 70 mg.

Until 2003, the exhaust gas cleaning was done with the "best practice" technical solution of electrostatic cleaning and dry absorption scrubbers (as used by all bake furnaces). In 2002, an experimental technique called the RTO (regenerative thermal oxidation) was introduced aimed at improving emissions performance. The technique was discussed with local authorities and accepted.

The rationale for the experimental project was that the existing best practice is a 35-year-old design, so something better should exist, and there had been complaints about odour in neighbouring small villages.

The new application was permanently put in place December 2003 and the results are expected to be at least 90% lower – a dramatic improvement.