Improved Production Economics for Cement Manufacturers

Primary aluminium smelting uses:

• large amounts of carbon
• silica refractory materials
• alumina as raw material
• sodium and fluoride chemical compounds as flux.

The spent potlining waste material from aluminium smelting has all of these materials inextricably mixed together. A next optimised stage in the lifecycle of these materials is to simultaneously:

• use the sodium and fluoride compounds as fluxes (1) and mineralisers (2) in energy intensive industries such as cement manufacture
• convert the carbon to thermal energy
• make use of the alumina and silica as raw materials.

Benefits include:

• economic and environmental gain from reduced energy requirements and reducing greenhouse gas emission
• cost effective access to fluxing and mineralising chemicals
• alternate and cost effective sources of fuel and raw materials.

Notes:

1. A flux is a substance that lowers the temperature at which solid materials enter a liquid phase and/or increases the quantity of liquid at a given temperature.
2. A mineraliser is a substance that accelerates reaction rates and promotes the formation of desired materials in the liquid phase of cement clinker or similar materials. This results in a higher quality product with less residence time and less energy for processes such as cement making.