Title: The Effects of Seed-Cotton Cleaning on Seed Coat Fragments Authors
Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 16, 2010
Publication Date: August 27, 2010
Citation: Boykin Jr, J.C., Ray, S.J. 2010. The Effects of Seed-Cotton Cleaning on Seed Coat Fragments. Journal of Cotton Science. 14:91-98. Interpretive Summary: Approximately 13 million bales of cotton were produced in the U.S. in 2008, most of which will be exported. It is important that this cotton is processed efficiently while maintaining the quality demanded by domestic and foreign consumers. One issue that is becoming increasingly important is fragments of cottonseed that remain in cotton bales after ginning. These seed coat fragments (SCF) can cause the yarn to break during spinning resulting in costly down time in the mill. In addition, when the yarn or fabric is dyed, the SCF absorb the dye differently than the cotton lint and cause discoloration that is undesirable in the finished product. In the U.S., cotton is mechanically harvested and ginned which leads to the formation of SCF. In a saw-type ginning facility, cotton containing seed (seed-cotton) is cleaned with cylinder cleaners and stick machines before being fed into a final cleaner called an extractor-feeder which feeds seed-cotton smoothly to the gin stand. The gin stand uses saws to separate fiber from the seed, and it is the major origin of SCF in a ginning facility. Seed-cotton cleaners have also been shown to damage seed. Therefore, the objective of this experiment was to determine if the use of seed-cotton cleaners prior to the extractor-feeder/gin stand causes increased SCF levels in ginned lint. Samples of lint were collected after an extractor-feeder/gin stand when no additional seed-cotton cleaners were in use, and samples were also collected after an extractor-feeder/gin stand which was preceded by a cylinder cleaner, stick machine, or both. Comparing samples revealed that the cylinder cleaner, stick machine, or the combination of these machines did not increase SCF levels beyond that which was found with only the extractor-feeder/gin stand. These results show that increased levels of seed-cotton cleaning before the gin stand do not cause SCF. Future studies are needed to determine how SCF may be prevented such as improved cotton harvesters, cotton varieties, or production practices. Results from this report will be vital to future research aimed at preventing SCF contamination in cotton bales. Implementation of this knowledge will help to increase the competitiveness of U.S. cotton.
Technical Abstract: Processing problems in textile mills have been linked to seed coat fragments (SCF), so preventing SCF from forming is one important goal of cotton ginning research. The primary objective of this experiment was to determine if seed-cotton cleaners used prior to the extractor-feeder/gin stand change SCF levels in ginned lint. Several cottons were processed at different moisture contents with different seed-cotton cleaners, and lint samples collected at the battery condenser were analyzed manually for SCF and motes. Samples were also analyzed with the Advanced Fiber Information System (AFIS) for seed coat neps (SCN) and neps. Analysis of lint samples revealed that cotton processed with either a cylinder cleaner or stick machine before the extractor-feeder/gin stand was not found to contain different SCF levels than cotton processed with only the extractor-feeder/gin stand. In most cases the same was true for the number of AFIS SCN, but AFIS neps were increased with the cylinder cleaner or stick machine. Also, cotton processed with a standard machine sequence (cylinder cleaner, stick machine, cylinder cleaner, extractor-feeder/gin stand, and two lint cleaners) was not found to have increased SCF levels in comparison to lint processed with only an extractor-feeder/gin stand and two lint cleaners. Again, this was generally true for the number of AFIS SCN, but AFIS neps were increased with the additional seed-cotton cleaners. In conclusion, seed-cotton cleaners were not found to increase SCF levels in comparison to the extractor-feeder/gin stand. Since the baseline treatment for comparison (the extractor-feeder/gin stand) included some seed-cotton cleaning, the conclusion could not be made that seed-cotton cleaners do not produce SCF, but the finding that additional seed-cotton cleaners produced no additional SCF was important due to the importance of these machines in removing other unwanted material from seed-cotton.