A major Australian mining company entering a significant growth phase required large dust extraction systems to control the dust generated from their proposed iron ore crushing and screening plants. Their environmental operating license requirements limited the filter emissions to 40mg/m³. Mine ventilation was also part of the expansion requirements.
Luehr Filter was selected to supply fabric filters and ventilation equipment for their two successive expansion projects in WA. The Luehr SMWF filters, which were installed on the crushing and screening plants, were commissioned during 2010/2011. They incorporated Luehr’s unique ‘reverse air offline’ cleaning system. This method of filter bag cleaning eliminates the need for compressed air during cleaning of the bags, a feature that greatly influenced the decision to award Luehr the dust control contract.
The offline cleaning feature not only ensures more efficient bag cleaning, but it also increases the overall collection-efficiency and bag life. Luehr’s reverse air offline units have been used extensively in Australia on cement milling applications, where they have demonstrated excellent robustness and reliability.
The fabric used in the filters includes a hydrophobic coating to handle the Pilbara’s high-humidity during the wet season. As with most Luehr designs, the filters supplied for these projects are based on a modular concept. This design allows the filters to be fully assembled and tested in the factory prior to shipping.
The units are achieving excellent dust control, exceeding the emission requirements and have high-uptime evidenced by the following feedback from a site engineer: "We have never had a maintenance or operational problem with the equipment, or anything that has effected production or been highlighted to my department for further investigation."