Dry fog application in surge hoppers and front end loader (FEL) hoppers is relatively simple.
Manifolds are typically used rather than individual nozzles, these manifolds have individual unidirectional nozzle mounts allowing the fog produced to be directed where needed. Hopper applications including truck dumps often have horizontally pointing nozzles as well as downward pointing, to provide a fog ‘blanket’ that prevents dust escaping with the action of displaced air that tends to flow upwards along the hopper walls. Manifold fitment is also simplified with one and and water connection to the manifold rather than individual conduits that have to be run back to the main cabinet for each nozzle.
FRONT END LOADER (FEL) HOPPER
Windfence material can also be used in exposed hoppers, this protects the fog where it is mounted above the bin by slowing air velocity and allowing the dry fog to be retained in the area it is needed. Windfence panels can be fitted around the hopper sides allowing the fogging manifold to be mounted out of harms way further away from the hopper top. Larger nozzles are also used where the nozzles are placed a distance from the hopper walls. This allows the area to be filled with fog without the possiblility of damage to the nozzles by rockfall or by the loader bucket.
Manifolds are mounted on the opposite side to the loader if possible, as well as the two perpendicular sides. This allows for suppression of the ‘upturned umbrella’ effect of dust as it tips into the hopper and pushes up the hopper sides.
Depending on the hopper size, DSN-6 or DSN-10 dry fog nozzles would be used for fugitive dust suppression. Where ore conditioning/moisture addition is desirable, water sprays can also be used in conjunction with the fog system to wet the product. The system can also be easily integrated into an automated system with proximity sensors or remote cab control if required.