CYCLONE SEPARATOR AND METHODS FOR CONVEYING DRY BULK MATERIAL
A cyclone type receiver can be used in a pneumatic conveyor system for accurately delivering a wide variety of particulate materials. A receiver may include a cylindrical body configured to hold a filter. The top end of the cylindrical body may include an air inlet for receiving a ducted air stream filled with a particulate material, and may be configured to convey the ducted air stream helically toward a conical section attached to the cylindrical section. The conical section may be configured to route the ducted air in a helical manner to remove the particulate material from the ducted air. In such a configuration, the filter and the conical section may remove particulate material, thereby preferably increasing the transfer accuracy of the system and reducing the footprint of a traditional pneumatic conveyor system.
1 . A cyclone separator comprising:
an inlet duct;
an outlet duct;
a receiver positioned in a flow path between the inlet duct and the outlet duct and configured to direct air comprising a dry bulk material from the inlet duct to the outlet duct;
a filter within the receiver and positioned within the flow path of the air comprising the dry bulk material, wherein the receiver comprises a lower conical section and an upper cylindrical section that together define a pressure vessel,
wherein the inlet duct and the outlet duct are positioned in the cylindrical section such that the air comprising the dry bulk material is directed into the cylindrical section, around the conical section helically, through the filter, and out of the outlet duct such that at least a portion of the dry bulk material is removed from the air and the inlet duct is positioned tangentially with respect to the wall of the cylindrical section and the inlet duct has an opening diameter Di from about 2.0 inches to about 5.0 inches,
wherein the cylindrical section has a diameter D from about 12 inches to about 31 inches and a height Lb and the conical section has a height Lc and an outlet of the conical section has a diameter Dd from 6 inches to 10 inches,
wherein the conical section comprises a centerline and an angle θ defined by (i) a horizontal plane perpendicular to the centerline and (ii) a sidewall of the conical section wherein the angle θ is from 70 degrees to 85 degrees,
wherein the height Lc is calculated as TAN(θ) multiplied by a length Ld wherein the length Ld is a first side of a right triangle formed with the sidewall of the conical section wherein the sidewall is a hypotenuse of the right triangle and the height Lc is a second side of the right triangle opposite angle θ and the length Ld is calculated as the diameter D minus the diameter Dd divided by 2, and
wherein the height Lb is from about 8 inches to about 55 inches.
2 . The cyclone separator according to claim 1 , further comprising a pair of air sweeps, wherein the air sweeps are located in the conical section and are diametrically opposed and vertically offset with respect to each other.
3 . The cyclone separator according to claim 1 , wherein the inlet duct has a centerline and the centerline is from about 2 inches to about 10 inches from a top of the cylindrical section.
4 . The cyclone separator according to claim 1 , wherein a transfer efficiency of the dry bulk material is from about 75 percent to about 100 percent.
5 . The cyclone separator according to claim 1 , wherein the dry bulk material comprises powder, seeds, granules, or grain.
6 . A system for accurately conveying dry bulk material in an extrusion-based manufacturing process comprising:
a cyclone separator configured to separate the dry bulk material from a carrier air;
a filter positioned in an upper section of the cyclone separator;
a feeder to store and feed the dry bulk material to the separator at a pre-determined rate;
a first rotary valve configured between the feeder and the separator;
a blower for generating the carrier air;
a moisture controller for regulating a moisture content of the carrier air;
a screw conveyor for conveying the dry bulk material further downstream;
a second rotary valve for discharging the material from the separator to the screw conveyor;
a first source of air for removing build up in the separator; and
an in-line filter positioned between an outlet duct of the cyclone separator and the blower.
7 . The system according to claim 6 , further comprising a vessel configured downstream of the cyclone separator for receiving the dry bulk material and incorporating the dry bulk material into or onto a pre-finished food composition.
8 . The system according to claim 6 , further comprising a second source of air for cleaning the filter.
9 . The system according to claim 6 , wherein the pre-determined rate is from about 0.05 lb/min to about 30.0 lb/min.
10 . The system according to claim 6 , wherein the feeder is a loss-in-weight feeder.
11 . A method for accurately and consistently introducing a volume of dry bulk material into or onto a pre-finished food composition in an extrusion-based manufacturing process comprising:
feeding a volume of dry bulk material from a feeder into a ducted flow of carrier air at a pre-determined rate;
directing the flow of carrier air comprising the volume of dry bulk material into an inlet duct of a cyclone filter separator;
controlling a moisture of the carrier air with a dehumidifier configured in a path of the carrier air;
separating a portion of the volume of dry bulk material from the carrier air and allowing the volume to pass through an outlet of the separator into a rotary valve;
conveying the volume of dry bulk material from the rotary valve into a vessel comprising the pre-finished food composition, the vessel selected from an extruder and a coater.
12 . The method according to claim 11 , wherein the pre-determined rate is from about 0.05 lb/min to about 30.0 lb/min.
13 . The method according to claim 11 , wherein the volume of dry bulk material comprising powder, seeds, granules, or grains.
14 . The method according to claim 11 , wherein the volume of dry bulk material comprises vitamins, minerals, colorants, probiotics or mixtures thereof.
15 . The method according to claim 11 , wherein the volume of bulk material has a particle size from about 20 um to about 5000 um.
16 . The method according to claim 11 , wherein the volume of dry bulk material has a bulk density from about 20 lb/ft 3 to about 90 lb/ft 3 .
17 . The method according to claim 11 , wherein the method is continuous.
18 . The method according to claim 11 , further comprising a filter cleaning sequence.
19 . The method according to claim 18 , wherein the filter cleaning sequence is performed concurrently with the separating.
20 . The method according to claim 11 , wherein the method has a dry bulk material transfer efficiency from about 75 percent to about 100 percent.