Submitted to: Transactions of the ASABE
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/27/2007
Publication Date: 5/1/2007
Citation: Holt, G.A. 2007. Design of experiments optimization study on the powered roll gin stand - Report 1. Transactions of the ASABE. 50(3):765-772. Interpretive Summary: The powered roll gin stand is a new ginning technology developed at the USDA-ARS Cotton Production and Processing Research Unit in Lubbock, TX. The gin stand has three main components; the paddle roll, the saw, and the seed finger roll. The speed and loading rate of these components have a significant effect on the ginning rate, turnout, and fiber properties of the seed cotton being ginned. This study reports on an optimization study performed in a commercial cotton gin on a conventional gin stand retrofitted with the power roll technology. This study reports several optimal solutions depending on the variables incorporated into optimization analysis. Results are reported for samples gathered before and after one stage of lint cleaning. If all thirteen response variables are used in the optimization analysis, the optimal operating settings were: 1) paddle roll speed (rpm) = 180 (before and after lint cleaning), 2) paddle roll loading = 100% of load (before lint cleaning) and 95% of load (after lint cleaning), and 3) seed finger roll speed (rpm) = 18 (before lint cleaning) and 40 (after lint cleaning). These results show how other equipment in the process stream can influence the optimal operational settings of the powered roll gin stand. The powered roll gin stand shows great promise in being the hub of a dynamic control system designed to custom gin seed cotton.
Technical Abstract: The powered roll gin stand has been evaluated in numerous studies in regards to increases in lint turnout and ginning rate without adversely affecting fiber quality properties. In some cases, improvements in fiber quality over conventional gin stands were noted. However, the question remained as to what speed the various components of the powered roll gin stand should be operated to optimize performance. The three main components of the power roll gin stand are: paddle roll, seed finger roll, and saw speed. This paper presents the results of an optimization study conducted on a power roll gin stand operating at a commercial cotton gin during the 2003-04 ginning season. The results are based on lint samples taken after the gin stand (before lint cleaning) and after one stage of lint cleaning, seed samples, and performance data. Of the thirteen response variables evaluated, four variables resulted in significant models: fiber length, short fiber content, ginning rate, and Rd (reflectance). Several optimal solutions were obtained based on the input factors used in the evaluation. When including all response variables in the analysis, the optimal operational settings for a Continental Double Eagle 141 before and after lint cleaning were: paddle roll speed = 180 and 180 rpm, paddle roll loading = 25 and 23.8 amps and seed finger speed = 18 and 40 rpm, respectively. The saw speed was held constant at 724 rpm.