As featured in Rock Products
by Kevin R. Peterson & Adam Schrage
Airborne dust and product spillage is one of the top quarry concerns in health, safety and environmental issues. Under the Clean Air Act, agencies such as the Environmental Protection Agency (EPA), Occupational Safety and Health Administration (OSHA), the National Institute for Occupational Safety and Health (NIOSH), and the Mine Safety and Health Administration (MSHA) have established guidelines and regulations of acceptable dust emissions for specific materials.
Companies involved in loading dry bulk material into trucks or rail cars are familiar with the advantages of utilizing telescoping loading spouts to mitigate the escape of dust into the atmosphere.
Not only does the spout telescope and retract to accommodate differing vehicle heights, the outer sleeve of the spout protects the material being loaded from the surrounding environment, as well as protecting the surrounding environment from potential dusting from the material.
Telescoping loading spouts offer the added benefit of extracting dust particles created during the loading process, route the dust particles to a dust collector filter, and re-entrain the dust back into the load. Telescoping loading spouts are extremely environmentally friendly.
When handling dry bulk material, dust or product has the potential of accumulating on the inner sleeve walls and the interior cones of the telescoping loading spout. As such, material can be discharged through the spout as it is raised or lowered, repositioned, or while it is at rest, waiting for the appearance of the next vehicle.
Over time, these small discharges of accumulated material can create a maintenance issue as it “rains down” on top of vehicles, within the loading area, or upon employees working nearby.
To address this issue, Vortex Global of Salina, Kan., developed a self-sealing discharge for applications where it is desirous to keep material within the confines of the spout.
The self-sealing discharge effectively closes off the discharge end of the loading spout. The mechanism only opens within the confines of the vehicle to be loaded after the spout seats into the loading hatch. The mechanism works through gravity and requires no additional motors or actuators.
How the Self-Sealing Discharge Works
As the spout is lowered, the cone at the bottom of the scavenger (1) seats into the vehicle’s open hatch.
The discharge’s interior mechanism (2) continues to extend down, into the interior of the truck or railcar.
This action unseals the dispersion cone (3), allowing dis- charged material to flow freely through the scavenger and into the vehicle.
Upon completion of loading, vibrators (4) positioned on the lifting ring and the scavenger cone are actuated for a short period of time to “shake” accumulated dust from the spout.
The spout is then retracted and a seal is created as the dispersion cone assembly seats into the scavenger.
Any remaining errant material is sealed within the confines of the spout itself, prohibiting material from escaping to atmosphere.
The relief dampers (5) at the side of the scavenger provide vacuum air in case a dust collector or filter are being utilized during the loading process.
The attachments at the bottom of the dispersion cone (6) accommodate level sensing devices if required.
The self-sealing discharge is a simple and efficient way to further contain errant material particles from discharging from the spout. It is another example of solutions brought to market by manufacturers to address health, safety, and environmental issues experienced by producers of dry bulk material.
About the Authors
Kevin R. Peterson is the business development director and Adam Schrage is the engineering manager for Vortex Global. Vortex Global serves customers throughout the world. Headquarters and manufacturing facilities are located in Salina, Kan.