Available Modules

Energy Use: Metal Casting - Zinc

Zinc smelting requires a large energy input. For electrolytic smelters, the main energy source is electric power. All four primary zinc producers in the USA utilize an electrolytic process.

On average, electrolytic smelters utilize power at about 3,400 kWh per ton of output product. An additional approximate 780 kWh per ton is consumed in other process steps (casting and casting dross processing). However, despite these large consumption levels, electricity is estimated to account for between 10 - 15% of the overall production cost. The range in costs is due to several factors including purity of the feed solution, current density of the cell, and operating condition.

The second energy commodity utilized is steam, used for heating the solution. The steam used is a part (about 40 to 50%) of the steam generated from the roasting step.

The following schematic shows the typical inputs and outputs for a zinc concentrate roasting process. This is the portion of a hydrometallurgical process where natural gas is most often utilized.