New Gin Dryer is More Efficient and Gentle on Cotton

A dryer developed by USDA’s Agricultural Research Service for use in cotton gins not only saves energy, but often improves the quality of the tens of thousands of bales each gin processes each year. That’s the word from cotton gins using the dryer, which can even handle cotton that’s been thoroughly soaked during rainstorms between harvest and ginning.

Sopping wet cotton often can’t be dried by conventional tower dryers. Tower dryers use a high-pressure blast of hot air to blow cotton pneumatically through a series of racks.

ARS engineer at Lubbock, Texas, designed the new dryer to force hot air through an even pile of cotton moving on a wire mesh belt. The belt is 6 feet wide and 40 to 70 feet long.

The hot air can dry the wettest of cottons because the belt moves slowly enough that the air has 90 seconds or more to do the job instead of 6 to 12 seconds with the tower dryer. The belt dryer uses air at 100 times less pressure than the tower dryer.

The dryer also uses only about half as much heat and a fraction of the horsepower requirements of tower dryers--resulting in sufficient energy savings for the new dryer to pay for itself in one to five years. Another plus: The belt dryer’s low heat reduces the chance of heat damage so it often does a better job of preserving fiber quality.

An article about the belt dryer appears in the June issue of Agricultural Research magazine.

Scientific contact: Joseph W. Laird, USDA-ARS Cropping Systems Laboratory, Lubbock, Tex., phone (806) 746-5353, fax 744-4402, wlaird@mail.csrl.ars.usda.gov.