Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: January 9, 1998
Publication Date: N/A
Interpretive Summary: Modern U.S. cotton gins use cyclone collectors to remove trash and fine dust from air conveying lines before releasing the air back to the atmosphere. The most common type of cyclone currently in use at cotton gins is the 1D3D design. It features a cylindrical upper body equal in height (1D) to its diameter, and a lower cone section that is 3 times longer (3D) than the cyclone's maximum diameter. While these types of cyclones have gained widespread acceptance in the ginning industry over the past 10 to 15 years, they have also created some unexpected problems. The 1D3D design features a tall, narrow inlet that has in many instances caused the cyclone to choke up and cease to operate properly. Field solutions to this problem have included changes to the inlet transitions connecting the cyclones to the round air conveying lines. The original flat top transitions are frequently inverted to overcome the choking problem. This solution, however, causes the cyclone to emit more dust to the atmosphere than normal. This paper describes and evaluates modifications to the inlet of the 1D3D cyclone that overcome both the choking problem and the dust problem. In addition, two other modifications were evaluated. One of these, an enlarged trash exit, also significantly improved cyclone performance.
Technical Abstract: A 2D2D type cyclone inlet was substituted for the tall, narrow inlet of the standard 1D3D cyclone in an attempt to overcome choking problems when using the standard flat-top inlet transition, or performance problems when using an inverted transition. This inlet modification lowered the modified cyclone's emissions by 8 to 9%, and slightly reduced its static pressure requirements. The 1D3D cyclone equipped with a 2D2D inlet operated satisfactorily with either the standard 1D3D type outlet duct, or the shorter 2D2D type outlet. The size of the cyclone's trash exit significantly affected PM10 emissions. A larger (D/3) size exit produced PM10 emissions that were about 8% lower than those resulting from use of the standard, small-diameter (D/4) exit.