Dust control system and method of operation

A machine comprising a vehicle;

• means at one end of the vehicle, constituting its forward end, for operation on material to be removed, the operation of said means being such as to cause dust to be present in the air at said forward end of the vehicle, which dust may include respirable dust comprising particles in the size range below 5 microns;
• and a dust control system for said machine comprising:
• a fan mounted on the vehicle spaced back from the forward end of the machine, said fan having an inlet and an outlet and means for causing a flow of air from the inlet to and out through the outlet;
• means on the vehicle forming a passage for induced flow of air from adjacent the forward end of the vehicle where dust is in the air to the inlet of the fan;
• a flooded bed scrubber in said passage means for effecting entrainment in droplets of water of dust, including respirable dust in said range, which is in the air flowing through said passage means, said flooded bed scrubber comprising a bed of fibers extending across said passage means through which the air may flow, and means for maintaining the fibers of said bed wetted with water, for entrainment in droplets of water of dust including respirable dust in said range by inertial impaction of the dust on the wetted fibers of the bed on drawing air through the bed at a sufficiently high velocity for said inertial impaction, the fan having the capacity for drawing the air through the bed at such velocity, the dust-laden droplets passing through the bed and downstream from the bed in the air flowing through said passage means;
• means for automatically maintaining the fan and means for maintaining the fibers of said bed wetted with water in operation for an interval on stopping the equipment;
• means in said passage means between the bed and the inlet of the fan for separating the dust-laden droplets of water from the air flowing through said passage means before the droplets reach the fan, said separating means being constructed and arranged for downward flow of the dust-laden droplets;
• a drainage system for the dust-laden droplets of water flowing down from said separating means comprising a sump on the vehicle below said separating means for receiving the dust-laden water;
• and
• means for disposal of the dust-laden water collected in the sump.

A machine comprising a vehicle having at one end constituting its forward end a boom pivoted for up and down swinging movement about an axis extending transversely of the vehicle and extending forward from the vehicle, a cutter head carried by the boom, and means for carrying away material cut by the cutter head comprising a conveyor extending longitudinally of the vehicle for conveying the material back toward the rearward end of the vehicle, said cutter head when operated to cut causing dust to be present in the air at the forward end of the vehicle, which dust may include particles in the size range below 5 microns, and a dust control system for said machine comprising:

• a fan mounted on the vehicle adjacent one side of the vehicle alongside the conveyor toward the rearward end of the vehicle, said fan comprising a housing having an inlet and an outlet and means in the housing for causing a flow of air from the inlet to and out through the outlet;
• a system of ductwork forming a passage for induced flow of air from the vicinity of the forward end of the vehicle to the inlet of the fan housing, said ductwork system comprising an air intake section associated with the boom and swingable up and down with the boom, said air intake section having bottom inlet openings for upward flow of dust-laden air from below the boom into said air intake section, and having an air outlet at its rear at said one side of the vehicle, said ductwork system further comprising a telescoping duct section and a fixed duct section extending longitudinally of the vehicle alongside said conveyor adjacent said one side of the vehicle from said air outlet of said air intake section to the inlet of said fan housing, said telescoping section being hinged at its forward end to said air outlet of said air intake section and hinged at its rearward end to the forward end of said fixed duct section;
• a flooded bed scrubber in said fixed duct section for effecting entrainment in droplets of water of dust, including respirable dust in said range, which is in the air flowing through said fixed duct section as a result of the cutting of the material, said flooded bed scrubber comprising a bed of fibers extending across said fixed duct section through which the air may flow, and means for maintaining the fibers of said bed wetted with water, for entrainment in droplets of water of dust including respirable dust in said range by inertial impaction of the dust on the wetted fibers of the bed on drawing air through the bed at a sufficiently high velocity for said inertial impaction, the fan having the capacity for drawing the air through the bed at such velocity, the dust-laden droplets passing through the bed and downstream from the bed in the air flowing through said fixed duct section;
• means for automatically maintaining the fan and, means for maintaining the fibers of said bed wetted with water in operation for an interval on stopping the cutting means;
• means for automatically holding the fan out of operation if water is not available for said means for maintaining the fiber of said bed wetted with water;
• means in the fixed duct section between the bed and the inlet of the fan housing for separating the dust-laden droplets of water from the air flowing through the fixed duct section before the droplets reach the fan, said separating means being constructed and arranged for downward flow of the dust-laden droplets;
• said fixed duct section having a bottom exit at the separating means for drainage of the dust-laden water therefrom;
• a sump on the vehicle below said exit for receiving the dust-laden water;
• and
• means for pumping to a place of disposal the dustladen water collecting in the sump.

A method of controlling dust generated by operation of equipment in an entry of a coal mine wherein the equipment is operated at the working face of the entry and its operation generates dust which may include respirable dust in the size range below 5 microns at said face, comprising:

• passing dust-laden air from said face through a dust control system comprising a passage and a fan, the flow being from the face through the passage to the fan, and being induced by operation of the fan to draw the dust-laden air through the passage,
• scrubbing dust from the air as it flows through said passage by entraining the dust, including said respirable dust in the size range below 5 microns, in droplets of water, the dust-laden droplets of water flowing downstream through said passage in the air flowing through said passage,
• separating the dust-laden droplets of water from the air flowing through said passage before the droplets reach the fan, whereby the fan operates in relatively droplet-free and dust-free air,
• and collecting and disposing of the dust-laden droplets.

A machine comprising a vehicle;

• means at one end of the vehicle, constituting its forward end, for operation on material to be removed, the operation of said means being such as to cause dust to be present in the air at said forward end of the vehicle, which dust may include respirable dust comprising particles in the size range below 5 microns;
• and a dust control system for said machine comprising:
• a fan mounted on the vehicle spaced back from the forward end of the machine, said fan having an inlet and an outlet and means for causing a flow of air from the inlet to and out through the outlet;
• means on the vehicle forming a passage for induced flow of air from adjacent the forward end of the vehicle where dust is in the air to the inlet of the fan;
• a flooded bed scrubber in said passage means for effecting entrainment in droplets of water of dust, including respirable dust in said range, which is in the air flowing through said passage means, said flooded bed scrubber comprising a bed of fibers extending across said passage means through which the air may flow, and means for maintaining the fibers of said bed wetted with water, for entrainment in droplets of water of dust including respirable dust in said range by inertial impaction of the dust on the wetted fibers of the bed on drawing air through the bed at a sufficiently high velocity for said inertial impaction, the fan having the capacity for drawing the air through the bed at such velocity, the dust-laden droplets passing through the bed and downstream from the bed in the air flowing through said passage means;
• means in said passage means between the bed and the inlet of the fan for separating the dust-laden droplets of water from the air flowing through said passage means before the droplets reach the fan, said separating means being constructed and arranged for downward flow of the dust-laden droplets;
• a drainage system for the dust-laden droplets of water flowing down from said separating means comprising a sump on the vehicle below said separating means for receiving the dust-laden water;
• and
• means for disposal of the dust-laden water collected in the sump.