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8 mbtu push-type burners with push plenu

Welcome to Onyx

inclined hot air cleaners over trashmast

Drying & Precleaning

Depending on the region of the world where it is produced, cotton may either be hand harvested or mechanically harvested (using either spindle-type pickers or brush-type strippers).  The type of harvesting will determine how much seed cotton drying and precleaning will be required to effectively remove the moisture and impurities (sticks, leaves, burrs, etc.) from the product.  Hand-harvested seed cotton will typically require a single stage of drying and precleaning, while mechanically harvested cotton will require two (or possibly three) stages. 

The Process

Based on the amount of moisture and trash in the incoming seed cotton, gin plants will typically be furnished with either one stage (for hand-picked cotton) or two stages (for machine-picked and machine-stripped cotton) of drying and precleaning machinery.  Gas or Oil-Fired Burners provide heat for the drying/conveying air.  Shelf-type Tower Dryers are sized and specified to provide for a prescribed ratio of heated air-to-seed cotton, so as to allow for maximum drying at reasonable air temperatures.   

From the Tower Dryer, the seed cotton is conveyed via the heated air stream to the Inclined Hot Air Cleaner, which uses spiked cylinders to convey the seed cotton across grid-type racks, removing small trash and further opening the cotton.  The Hot Air Cleaner also serves as the separation point for the seed cotton from the now moisture-laden and dirty air.  Attached to the discharge hood of the Hot Air Cleaner is a Vacuum Wheel (or rotary air lock), which seals the Hot Air Cleaner from the subsequent machine(s) in the system. 

The second cleaner in the first-stage precleaning system is an extractor-type cleaner, in which the seed cotton is fed via gravity onto channel saw-type extractor cylinders.  These cleaners are designed to remove sticks, leaves, and heavier trash from the seed cotton, once it has been through at least one stage of drying.  In machine-picked seed cotton regions, the extractor cleaner is typically a Lummus 3-Saw Stick Machine or Little Giant™ Stick and Green Leaf Machine, while in machine-stripped areas, either stacked (2) 3-Saw Stick Machines or the Lummus Stripper and Ground Harvester (S&GH™) Machine are usually furnished.  In especially rough-harvested cotton regions, multiple configurations of extractor cleaners may be mounted under the first-stage Hot Air Cleaner. 

The second-stage drying system typically will feature a separate burner for its source of hot air, but it may borrow heat from a single, larger burner.  Depending upon the level of incoming moisture, a gin plant may or may not feature a second-stage Tower Dryer.  Often, conveying the seed cotton from the first-stage precleaning to the second-stage precleaning in a heated air stream (using conventional round piping) supplies more than adequate conditioning for the cotton. 

The second-stage precleaning system (or first-stage system for hand-picked regions) consists of an Inclined Hot Air Cleaner alone or a Hot Air Cleaner mounted over a TrashMaster™ Cleaner. The Hot Air Cleaner serves the identical purpose as in a first-stage system, while the TrashMaster™ Cleaner (a specially-designed, gravity-fed spiked cylinder machine) removes bark, sticks, stems, large leaves and grass through the use wider-spaced grid rods to allow a certain amount of good seed cotton to be thrown off with the fibrous-type trash.  This good seed cotton is then reclaimed and returned to the seed cotton flow by the TrashMaster’s extractor-type reclaimer section before it is discharged into the trash line.  For extremely rough-harvested seed cotton, instead of a TrashMaster™ as the final cleaner, an extractor-type Stick Machine may be substituted. 

First-Stage Drying System
First-Stage Precleaning System
Second-Stage Drying & Precleaning System

Available Options

  • Gas-Fired Burner (available in 1, 5, 8, 12, and 16 MBTU sizes for both push-type and pull-through operation) 

  • Turbulent Dryer Trap (shown) (40” and 60” widths available)  

  • High-Capacity Rock Catcher (10” x 48” and 13” x 48” sizes available) 

  • High-Volume Tower Dryer (27” shelf spacing) (48” and 72” widths available) 

  • Standard Tower Dryer (13½” shelf spacing) (48” and 72” widths available in 7/8-shelf, 11/12-shelf, and 15/16-shelf configurations) 

  • Vortex-Tube™ Dryer 

  • Horizontal Precleaner (120” and 144” widths available in 9-cylinder, 12-cylinder, and 15-cylinder configurations) 

  • Inclined Hot Air Cleaner (96”, 120”, and 144” widths available in 6-cylinder or 9-cylinder configurations with either standard-duty or heavy-duty spiked cylinders) 

  • Vacuum Wheel, 34” diameter (72”, 96”, 120”, and 144” widths available in both 22½” and 34” diameters) 

  • 3-Saw Stick Machine (120” and 144” widths available) 

  • Little Giant™ Stick & Green Leaf Machine (96” and 144” widths available) 

  • S&GH™ (Stripper & Ground Harvester) Machine (96” and 144” widths available) 

  • TrashMaster™ Cleaner (96”, 120”, and 144” widths available) 

  • Inclined Gravity Cleaner (96”, 120”, and 144” widths available in 6-cylinder or 9-cylinder configurations with either standard-duty or heavy-duty spiked cylinders) 

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