Location: Cotton Ginning Research
2018 Annual Report
Objectives
1. Enable, from a technological standpoint, new commercial methods and processes to reduce energy use, labor costs, and environmental impact, while preserving cotton fiber and seed quality, during the saw-ginning of picker-harvested cotton.
1.A. Develop a fan speed control system for conveying fans used at gins to reduce energy inputs.
1.B. Develop improved systems for drying seed cotton to optimum moisture levels with reduced energy inputs.
1.C. Determine effect of higher than recommended processing rates on fiber quality and losses.
1.D. Improve understanding of the fundamentals of pneumatic conveying of seed cotton and lint.
1.E. Determine the cause of fiber breakage prior to ginning, which results in fiber and seed losses during processing.
2. Enable new commercial methods and machinery to improve product quality in the saw-ginning of picker-harvested cotton.
2.A. Develop machinery and processes to remove plastic contamination at the gin.
2.B. Determine causes of increased bark content of picker-harvested saw- ginned cotton.
2.C. Improve foreign matter removal by seed cotton cleaners, thus reducing the need for lint cleaning and associated fiber damage.
2.D. Apply high-speed roller ginning equipment for use with picked cotton in the humid region of the United States.
2.E. Improve foreign matter removal by lint cleaners, thus reducing the need to use an additional stage of lint cleaning.
3. Identify material properties that have a significant impact on fiber and seed quality during saw-ginning, and enable new or improved, commercial methods for measuring product moisture content and process mass flow rates during ginning.
3.A. Develop a mass flow rate sensor for seed cotton.
3.B. Improve seed cotton moisture content measurement during the ginning process.
3.C. Identify cotton properties or measurable process parameters indicative of fiber damage occurring in the gin stand.
3.D. Develop a system to measure the fiber removed by gin cleaning machinery.
Approach
The work includes a variety of specific activities. A fan speed control system will be developed to reduce energy inputs. With this system fan electricity use will be reduced by using a control system with no negative effects on gin operation. An improved system for drying seed cotton will optimize moisture levels with reduced energy inputs using computational fluid dynamics models.
Acceptable leaf grades and extraneous matter levels will be achieved with higher processing rates through seed cotton and lint cleaners using the recommended sequence of ginning machinery. A new ginning system is under construction at the CGRU that will allow testing of processing rates comparable to commercial gins through the extractor-feeder and lint cleaner.
Machinery and processes will be developed to remove plastic contamination at the gin. Work will concentrate on developing a retrofit or change in operation of existing seed cotton cleaning equipment. ARS engineers will examine causes of increased bark content of picker-harvested saw-ginned cotton. ARS engineers will improve foreign matter removal by seed cotton cleaners, thus reducing the need for lint cleaning and associated fiber damage. ARS engineers will use high-speed roller ginning equipment with certain cultivars grown in the humid region of the U.S. which will result in longer fiber with less short fiber and fewer neps.
Seed cotton mass flow rate will be accurately predicted using a system based on air velocity, conveying system static pressure, and temperature measurements. The weight of seed cotton used for each test run will be recorded and linear regression will be used to identify model parameters in the improved model, which will include the static pressure measurement. More accurate prediction of seed cotton moisture will be made using the temperature drop that occurs during the drying process.
Power measurements of individual gin stand components and fiber properties determined from HVI or AFI will be used to predict short fiber and nep content occurring due to different processing conditions, such as moisture and ginning rate. Samples will be ginned and electricity use will be monitored. Predictive models for fiber quality parameters, particularly short fiber and nep content, will be developed for each genotype based on energy data and moisture content.
Measurement of fiber loss during cleaning is an important part of understanding the ginning process and control of that fiber loss may be related to other factors being studied. The proposed measurement system for the quantity of fiber lost from cleaning machinery includes a measurement of the proportion of material with cotton fiber color and a measurement of the total cleaner waste mass flow rate.
Progress Report
An experimental device was designed and constructed for quality-based seed-cotton separation. The device includes a fan, cotton feeder, pipes, and a passway. The prototype of the device was tested for performance. Results indicated that the device functioned as designed. Using this device, the experiments have been conducted. Seed-cotton was fed into a pressured-air flow and blown out of a pipe. To find its behavior in the airflow for detecting plastic contamination in ginning process, plastic films from the cotton round-module wrapper in various sizes and thicknesses were also dropped into the feeder along with the seed-cotton. The seed-cotton and plastic films, which were blown out from the pipe, drifted down into the 40-ft long passway which was divided into 6 sections. All the cotton and plastic films in each section of the passway was collected separately as the sample in that section. Approximately 1,600 lb seed-cotton and 100 pieces of plastic films were used in the experiments. The seed-cotton samples were weighted and processed for lint properties including fiber length, fiber strength, short fiber content, and turnout rate. The plastic films from each section were counted for the film’s behavior analysis. The fan speed, air pressure, cotton-feeding rate were recorded as well.
An air-bar prototype was designed and built. The air-bar developed was implemented in a lint cleaner to replace the traditional grid-bar. The air-bar lint cleaner (ABLC) was tested with different air pressures supplied. Experiments were conducted to compare the performance of air-bar lint cleaner with the traditional grid-bar lint cleaner (GBLC). Samples of the lint that was processed by the ABLC and GBLC were collected. HVI and AFIS properties of the samples including fiber length, strength, short fiber content, and trash content were tested and compared between the lint processed by the ABLC and the lint by GBLC.
A UAV and multi-spectrum camera were purchased to build a UAV-based imaging system. Using this system, aerial images of cotton fields were acquired to detect plastic films in the field.
Accomplishments
Review Publications
Hardin IV, R.G. 2018. Seed Cotton Mass Flow Measurement in the Gin. Applied Engineering in Agriculture. 34(3): 535-541. https://doi:10.13031/aea.12647.
Hardin IV, R.G., Barnes, E.M., Valco, T.D., Martin, V.B., Clapp, D.M. 2018. Effects of Gin Machinery on Cotton Quality. Journal of Cotton Science. 22:36-46.
