A reoccurring topic in regional meetings across the Cotton Belt in 2018 has been contamination — in the field, in gins, in bales, and ultimately in textile manufacturing.
Unfortunately, this issue doesn’t seem to be fading for the 2018-2019 growing and ginning seasons. Cotton in the United States has long been known for being clean and contamination free, but it seems this reputation is at risk of being lost.
Plastic Contaminants
Contamination is a multi-faceted problem and can have many sources. The cause for concern this year has been the reoccurrence of plastic pieces. In 2016, the U.S. Department of Agriculture Classing Offices did not officially record whether a “61” code for “other contamination” was for plastic or not. However, it’s estimated calls due to plastic that year were fewer than 250.
In 2017, more than 2,600 samples received a “61” code specifically for some sort of plastic. About 87 percent of these calls were for pink or yellow module wrap plastic, while the remaining samples had some sort of plastic bag, plastic vegetable mulch, twine or miscellaneous plastic matter.
No matter the source or size of the plastic, manufacturing mills across the globe are urging the U.S. cotton industry to decrease the contamination amount going forward. For the 2018-2019 season, the USDA Classing Office will be implementing a code “71” or “72” specifically for plastic contamination in samples.
Each segment of the industry can implement practices to assist with decreasing the amount of contamination that makes it to the end bale of cotton. During field harvest, it is imperative that producers remain diligent about removing debris so it does not end up in the harvest equipment and then in the module.
The National Cotton Council has published educational efforts and videos to help producers and their employees understand the importance of being aware of what is in the field. Videos for gin managers and staff are also available for proper module wrap cutting and gin equipment cleaning.
These videos can be viewed on the NCC website: http://www.cotton.org/tech/quality/contamfree.cfm
Color-Detecting Camera
Cotton Research and Promotion Program funds have been specifically designated to examine different types of machinery to detect and remove plastic in the gin. One of these projects is being conducted at the Lubbock Gin Lab in coordination with researchers Matthew Pelletier, Greg Holt, John Wanjura, and the Cotton Incorporated Fiber Competition and Ag Research team.
This project focuses on using a color-detecting camera to scan for a specific color scheme. When the specified color is detected, an air ejection system removes the piece of contamination along with any cotton that might be attached to it.
This technology could potentially be used at the gin-stand feeder apron, the point with the thinnest flow of cotton. A small-scale model of the machine has been tested and has shown promising results.
Extraction Machine
Another Cotton Incorporated-funded project being conducted at the Las Cruces Gin Lab is a small-scale version of the Golden Lion Extraction Machine currently used in some parts of China. This machine works within the stick roller area to help loosen the contaminant, followed by an airflow chamber that removes the item before it enters the ginning process. It will be evaluated to see if modifications are needed for use in a commercial gin and if it’s even feasible for gins to purchase.
There is not one solution that will solve the problem of plastic contamination. A variety of efforts need to be employed to ensure each module and bale is as clean as possible. The entire U.S. cotton industry is facing this problem head-on.
The Cotton Research and Promotion Program is looking at ways to help fund research to assist at the farm and gin levels. And hopefully soon, a promising solution will be on the horizon.
Christi Chadwell is the Cotton Board’s regional communication manager for the Southwest. Please contact her at cchadwell@cottonboard.org.