One of the major environmental problems identified Karara Mining Limited’s magnetite mine was excessive dust generated in and from the primary crusher ROM Bin, mainly due to truck dumping. In some cases, depending on wind directions, the truck became totally consumed by the dust cloud.
An additional problem was the excessive amount of water used by the ineffective existing water sprays (up to 1000 litres/min).
Comparison of old Water Spray System (left) and new EnviroMist Dust Suppression System (right)
Joint initiatives were undertaken by EnviroMist and BMEA to develop and establish:
- New dust suppression technologies (for both greenfield and existing mine sites)
- Use of best practice technology and innovation available for dust suppression
- Improved pollution prevention and water efficiency for mining applications, including ROM Bins
- Compliance with applicable legal requirements and obligations
EnviroMist Dust Suppression System, showing Micro-Mist Curtain (left) and special Corner Blocks (right)
After installation of the new EnviroMist micro-mist dust suppression system, 100% success has been achieved with all dust emissions being suppressed and contained inside the ROM Bin. This excellent result has continued over time, even with strong cross-winds. Water consumption has also been reduced by over 60%.
The Department of Mines and Petroleum WA carried out an inspection of the ROM Bin and were amazed with the performance of the new dust suppression system. They gave it a comprehensive “tick of approval”.
This successful project demonstrates how a large and difficult problem can be solved using new innovative technology and design/modelling methods that incorporate all relevant factors. The benefits to the environment are significant with dramatic reductions in workplace/plant dust emissions, and also water consumption.