Getting Cotton Moisture Just Right for Processing

							Getting Cotton Moisture Just Right for Processing
DAVID NANCE (K5927-21)




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         otton is the world’s most widely     The research is now part of a 3-year co-      processed with less moisture yielded
         used textile fiber, with U.S.        operative research and development            inferior yarn.
         growers providing 20 percent of      agreement with Cotton Conditioners,              In the future, many gins will have
         the world’s output.                  Inc. (CCI), of Knoxville, Tennessee, to       automated moisture-control technology
   Maintaining proper moisture in cotton      see how this approach works in a real-        so bales will emerge from the gin with a
bales is critical for successful textile      world setting. Together, ARS and CCI          prescribed amount of moisture. ARS re-
processing. Too little moisture and the       will develop, evaluate, and commercial-       searchers at Clemson and at the Cotton
cotton is susceptible to damage. Too          ize an effective automated system to          Ginning Research Unit in Stoneville,
much moisture makes cotton stick to           measure and adjust moisture content of        Mississippi, are working together to de-
machinery components. So investigators        cotton during processing in textile mills.    termine the optimum moisture level for
in ARS’ Cotton Quality Research Unit              At the mill, cotton bales are typically   storage. If it’s found to be the same as
in Clemson, South Carolina, are working       opened and allowed to condition, or rest,     for initial processing at the mill, then
to make it easier to regulate the amount      for at least 24 hours. This allows them       bales may need to be hydrated only
of moisture throughout processing.            to “bloom” as they reach moisture equi-       once—at the gin. In the meantime, mois-
   The scientists, led by textile technolo-   librium with their surroundings. But in       ture control during bale opening at the
gist David D. McAlister, used various         this age of just-in-time manufacturing,       mill may provide a rapid, practical solu-
methods to condition samples taken from       it’s no longer practical to do this. Plus,    tion to the industry’s cotton bale condi-
a bale of cotton. Some were left in am-       moisture levels aren’t monitored during       tioning problem.—By Jennifer Arnold,
bient room conditions, and others were        this conditioning time.                       formerly with ARS.
sprayed with water—both with and with-            In McAlister’s unit, researchers mon-        This work is part of Crop Quality and
out a wetting agent to improve water          itored 250 cotton bales being prepared        Utilization of Agricultural Products, an
absorption. Then, the team measured           for cotton mills. Bales arriving from the     ARS National Program (#306) described
fiber properties and yarn tensile strength    gin contained from 2.3 percent to 8.2         on the World Wide Web at http://nps.ars.
of each sample to see which moisture          percent moisture. Those already at 8.0        usda.gov.
level most improved cotton fiber              percent—the recognized commercial                David D. McAlister is in the USDA-
processability.                               ideal—went straight to processing.            ARS Cotton Quality Research Unit, Rav-
   They found that a spray of 4 percent           When bales that were low in moisture      enel Center Place, Room 10, McGregor
water plus 2 percent wetting agent—a          were boosted to a moisture content of at      Road, Clemson, SC 29631; phone (864)
total of 6 percent added bale weight—         least 6.5 percent, processing and fiber       656-2488, fax (864) 656-1311, e-mail
best maintained fiber and yarn strength.      and yarn quality improved. Bales              dmcal@clemson.edu. x