After almost 30 years of utilization, a North-American Silver- and Gold-Mine took action together with specialists of Martin Engineering to update its conveyor system with improvements regarding safety, spillage reduction, endurance and efficiency.
Robert Stepper, Richard Shields
(ed. wgeisler - 27/2/2017)
“Bulk material bounces when it comes in contact with a fast moving conveyor and often shifts as it travels over carrying idlers.” explained Marshall. “Occasionally, some material ejected from the belt will be collected on its non-carrying side. If trapped between the tail pulley and the belt they can do significant damage to both.”
To complete the containment system, technicians also installed an integrated air cleaner, which contains a suction blower, filtering elements and a filter cleaning system. Instead of a centrally located unit connected to dust generation points via ductwork, the Martin air cleaner is incorporated into the dust generation point itself.
The particles are not extracted, but are instead collected within the enclosure and periodically discharged back into the material stream using a pulse of compressed air. As material is captured by the filters, it agglomerates against the filter media. When the filter media is pulsed, the material will fall. If it is agglomerated and large enough, it will fall back into the material stream. The pulse system is designed to alternate pulses to each filter element. When one filter is being pulsed, the adjacent filter is still drawing air. If a pulsed particle is too small to drop out of the air stream, it is immediately pulled into an active filter.
The integrated air cleaner is an independent unit positioned directly at a dust generation point.
Like the central system, integrated units use negative pressure, with airflow created by a blower sized to provide the airflow needed for the pickup point. As there is no ducting, there are no pressure losses other than the filters that must be accounted for. Because of this, the power requirements of an integrated air cleaning system are far lower than for central collection systems.
The entire upgrade was completed within the seven-day shutdown, and the results were immediately apparent. Instead of spending 7 to 10 man-hours per day, now there is one man going down there with a broom every few days.
The upgraded conveyor now requires only minimal clean-up, instead of as many as 70 man-hours per week.
Because of the installation's success Coeur Rochester is currently evaluating five additional conveyor areas for its next upgrade.