The Baie-Comeau Smelter’s carbon sector is equipped with a closed-loop water management system and, therefore, generates no wastewater. In the casthouse, the cooling waters are recycled and treated, and only the blow-off water is discharged into the environment. Raw water is sourced from Lac La Chasse, the reservoir for the municipality of Baie-Comeau, and is treated at the plant to render it potable.
Water consumption was generally stable compared to 2011. Industrial water consumption increased slightly due to a warmer summer, which required more water to cool the compressors.
The Bécancour Smelter sources its industrial water from the Bécancour industrial park and uses the potable water treated by the City of Bécancour. The cooling water used at the casthouse is industrial water that has been repeatedly recycled. Only the blow-off water is discharged into the environment. In the carbon sector, potable water is used to cool the anodes and the exhaust from the bake ovens. This water is either re-circulated or evaporated (zero discharge). Potable water is also used to cool the compressors. Water is discharged at the cooling towers.
Potable and industrial water consumption was stable at the Bécancour Smelter in 2012.
The Deschambault Smelter obtains it process water from the rainwater that falls at the site. Potable water, provided by the municipality, is used only for sanitary purposes. Because this plant is designed with a recycling and zero discharge system for process water, it uses only a minimal amount of water for manufacturing. This is true both in the carbon sector and at the casthouse.
Potable water consumption was stable at the Deschambault Smelter. The increase in industrial water use compared to previous years is attributable to the replacement of a faulty counter.
Bécancour Rod Plant
Like the Bécancour Smelter, the Bécancour Rod Plant sources its industrial water from the industrial park and its potable water from the City of Bécancour. For the last few years, potable water consumption at the rod plant has increased, while industrial water use has decreased (zero consumption in 2012). This is attributable to the high concentration of suspended solids in the industrial water during certain times of the year, which does not meet the plant’s effluent quality criteria. This forces the plant to use potable water in its manufacturing process. A filter was installed at the cooling tower blow-off in 2012, and the rod plant should now be able to reconvert most of its industrial water supply, depending on water quality.
Water consumption increased in 2012 compared to previous years following an equipment failure in July, which caused emulsion from the rolling mill to infiltrate the cooling water (lowering of discharge targets).