Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: January 31, 1999
Publication Date: N/A
Interpretive Summary: Dryer control systems do not adequately dry cotton modules when the bottom few inches of the module are extremely wet but the remainder is dry. Automated dryer control systems respond to the average moisture content. During testing of the dryer control system many cases were observed where the average moisture content of the module was low and the control system responded properly by setting the drying temperature low. In some cases the module had a very wet bottom and wet portion was dried very little which caused the gin stand to stop. An electronic sensor was designed, tested, and a prototype installed in a commercial gin for field testing. The system worked as designed in all respects, however, during 1998 the weather for harvest was nearly ideal and no modules were encountered which had extremely wet bottoms. Based on the findings when the bottom of the module was artificially wet, the system responds appropriately if needed. Application of this new technology will enhance automated control of the drying operation and thereby improve the quality of cotton produced by U.S. gins.
Technical Abstract: Recent innovations have enabled samples of cotton to be automatically captured, evaluated, and released in gins. Sensors which measured the moisture content of seed cotton from throughout the module at the module feeder and the lint after the gin stand have been used to control drying. The system worked well except for a few modules which had very wet cotton on the bottom which was not indicated by the sensors. In 1998, a system to measure the moisture content of the bottom of the module was designed, installed, and tested. This new sensor was used to raise the drying temperature if the bottom was extremely wet. The system was run successfully in a commercial gin throughout the 1998 ginning season. The calibration was checked before and after the season and no significant differences were observed. The measurement range was from below 8% to above 15% wet basis. The average module bottom moisture content was about 10%. The sensor functioned as expected to artificially wetted seed cotton. However, no modules were encountered during the 1998 ginning season which had extremely wet bottoms so the control portion of the system could not be tested. In all respects the system worked as designed and is believed to be ready to respond properly when needed.