Submitted to: Cotton Gin and Oil Mill Press
Publication Type: Popular Publication
Publication Acceptance Date: 2/10/2003
Publication Date: 4/25/2003
Citation: ANTHONY, W.S. SURVEY OF MOISTURE RESTORATION AT MIDSOUTH GINS IN 2002. COTTON GIN AND OIL MILL PRESS. 2003. 104(7):10-12. Interpretive Summary: Cotton reaches a natural moisture equilibrium in the field before harvesting and continues to equilibrate during storage before ginning. Gins then remove moisture from the cotton to improve cleaning efficiency that also reduces bale weight. Many gins restore some of the moisture lost since harvesting using humidified air or direct water spray immediately before the bale packaging process. The final bale moisture should not exceed 8%. The amount of moisture added by various technologies at the gin and whether it is the correct amount is not known. Eighteen gins that used the commercially available types of moisture restoration systems were surveyed in 2002. Samples were taken for moisture content before and after moisture restoration from 25 consecutive bales on at least 3 occasions during the 2002 gin season. The average moisture before and after moisture restoration was 5.1% and 6.2%, respectively, representing about 5 pounds of increased weight. Final moisture contents averaged at individual gins ranged from 4.2 to 7.7%. The final moisture contents were well within a safe range for 91.4% of the bales; however, 10 of the surveyed gins had bale moistures exceeding 8%. This practice may cause quality degradation during extended storage and negatively impact the utility of the fiber. Additional research is required to develop better moisture application and control methods.
Technical Abstract: Moisture restoration practices were surveyed in 18 gins in Mississippi and Arkansas in October and November 2002. The types of moisture restoration systems surveyed were: 1) lint slide grid, 2) humidified air at/near the battery condenser, 3) direct water spray at the lint slide, and 4) combination of 2 and 3. For this survey, one sample was taken from each bale before moisture restoration and another one after moisture restoration for 25 consecutive bales of cotton on three or more different days during the season. Initial moisture contents averaged for individual gins ranged from 3.7 to 6.2%, and final moisture contents averaged at individual gins ranged from 4.2 to 7.7%. The simple average across all samples and gins for initial and final moisture contents was 5.1% and 6.2%, respectively, thus about 5.5 pounds of moisture was added per bale. Bales may be stored safely at moisture levels below 8%. However, 8.6% of the bales were above the safe storage moisture of 8%. Ten of the 18 surveyed gins produced bales that exceeded the 8%, mostly with the direct spray or combination methods of moisture restoration. These bales may experience quality degradation during extended storage.