Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: 1/16/2009
Publication Date: 5/15/2009
Citation: Baker, K.D. 2009. Air temperature variation across the seed cotton dryer mixpoint. National Cotton Council Beltwide Cotton Conference. 2009 CD 503-513. Interpretive Summary: In order to improve the effectiveness of cleaning equipment, cotton is generally dried with heated air as it first enters the gin. Tests were conducted to check for temperature variation within eighteen cotton drying systems in six gins. The tests were conducted in west Texas, the San Joaquin Valley, California, and other western U.S. locations. Results for air temperature variation within the heated air stream before it is used for drying indicated that some systems had a temperature difference of 100 F or more. Temperature differences this large would result in uneven drying and less effective cleaning. Further testing should be done that would investigate methods of reducing the temperature variation for drying systems with problems in that area.
Technical Abstract: Eighteen tests were conducted in six gins in the fall of 2008 to measure air temperature variation within various heated air seed cotton drying systems with the purpose of: checking validation of recommendations by a professional engineering society and measuring air temperature variation across the airflow ductwork preceding the mixpoint of heated air seed cotton drying systems. The cooperating gins were located in west Texas, the San Joaquin Valley, California, and other locations in the western U.S. Drying systems tested include: tower, pipe, crossflow blow-box, hot box, hi-slip, fountain – collider type, and vertical type systems. Regarding air temperature variation across the airflow ductwork preceding the mixpoint of heated air seed cotton drying systems, five of the eighteen systems tested had significant variation in air temperature, ranging up to a temperature difference of 120 F (67 C) among the four locations tested. Drying systems which dispersed the drying air across large widths (up to 8 feet or 2.5 m), such as the crossflow blow-box and the hi-slip drying systems, were more likely to have a large variation than were systems which kept the drying air concentrated, such as the pipe, jet, and pipe-fed tower drying systems. Systems which were operated at higher temperatures (above 250 F or 121 C) also showed a larger variation in temperature than that for systems which were operated at a low temperature (below 200 F or 93 C). Further testing should be done that would investigate methods of reducing the temperature variation for drying systems with problems in that area.