Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: January 8, 2000
Publication Date: June 15, 2000
Citation: HOLT, G.A., LAIRD, J.W., BAKER, R.V., FUNK, P.A. MODIFICATIONS AND IMPROVEMENTS OF TWO SEED COTTON UNLOADING SYSTEMS. PROCEEDINGS OF THE BELTWIDE COTTON CONFERENCE. 2000. V. 2. P. 1563-1571. Interpretive Summary: Pneumatic conveying systems are widely used throughout the cotton ginning industry. These systems account for a majority of the power requirements necessary to operate a gin. Inefficiencies in these systems can be costly and result in reduced processing rates and poor performance of the equipment. Efficiencies of pneumatic conveying systems are commonly associated with pressure loss across the system. But, how accurate are the equations used to estimate those losses when compared to "real world" systems? This paper documents modifications made to the seed cotton unloading system at the USDA-ARS Lubbock, TX gin lab and compares the measured pressure losses against those calculated by two different methods commonly used. Results show the equations were within the range of less than 1% to 19% of the measured losses, depending on the equations used. Overall, the importance of properly sizing pipe, operating equipment at minimum pressure drops, and sealing leaks are made evident by the fact tha the velocity in the suction telescope was increased 19% using 37% less power.
Technical Abstract: Pneumatic conveying systems are commonly used in the cotton ginning industry. Inefficiencies in those systems can reduce productivity, create choke ups and result in high operating costs. The fact that inefficient pneumatic conveying systems are costly is nothing new to the ginning industry. But how can system losses be determined and how accurate are the equations recommended for calculating those losses? The purpose of this paper is twofold: 1) document modifications that were made to the seed cotton unloading system at the USDA-ARS Lubbock, Texas ginning laboratory and compare those changes to values that were obtained from using standard friction loss calculations found in the literature, and 2) report the effect that reducing or eliminating the inefficiencies had on power consumption. The results showed that the equations ranged from less than 1% to 19% of the actual measured system losses, depending upon the calculation nmethod used. Modifications resulted in a 37% reduction of power usage in the unloading system.