Texas Tech University

From Field to Fabric

By: Sally Logue Post and Norman Martin 

Cotton is still king in Texas, producing the vast majority of the nation's cotton with about two-thirds of the production occurring in the High Plains area in the northern portion of the state.

At the center of all that production sits Texas Tech University, with agriculture research programs that cover just about every aspect of cotton production from seed development to the fiber used in your blue jeans.

The university's Fiber & Biopolymer Research Institute (FBRI) recently added a key piece to its research infrastructure, a one-of-a-kind micro-gin. The custom-built ginning laboratory is expected to put the FBRI near the top of the nation's most sophisticated cotton research facilities. 

“This equipment gives us the ability to closely match ginning conditions that cotton fibers will experience in commercial ginning conditions,” said Noureddine Abidi, FBRI managing director. “It gives us the ability to observe the actual performance that can be expected from a particular cotton when processed commercially.”

A 20 Year Dream

The installation of the gin brings a 20-year dream to reality for Eric Hequet, chair of the Department of Plant and Soil Sciences.

“When I was a cotton breeder working in Africa, our operation had a gin,” he said. “When I came to Texas Tech, we had some textile operations in place, and I wanted to add a gin. It just took a while to accomplish.”

cotton microgin
The micro-gin is a transparently sided, scaled-down version of Georgia-based Lummus Corporation commercial cotton ginning equipment.

The micro-gin is a transparently sided, scaled-down version of Georgia-based Lummus Corporation commercial cotton ginning equipment found in numerous gins across the South Plains and the state. Lummus is a leading supplier of machinery and replacement parts for the cotton-ginning industry. 

The gin is important not just as an education tool, but it is a big step forward for Texas Tech cotton research. With nearly 80 percent of the nation's cotton exported, Hequet emphasizes that American cotton must compete with the rest of the world's cotton.

“Due to limited water resources, it is difficult to compete with the rest of the world on yield, so we must compete on fiber quality,” Hequet said. “Yet even if you can develop cotton breeds that produce the best length, if you destroy the fibers at the gin, you have nothing.”

And that's where the new micro-gin comes in. The FBRI works with cotton breeders across the country. By putting cotton through the stress of the full ginning process, researchers will be able to see where adaptations can be made to maintain the quality of the cotton fiber.

“We are looking at how to optimize the interaction between cotton fibers and the ginning process to preserve fiber quality,” he said. “The goal is to identify germplasm resources that can withstand better mechanical processing. This should lead to less fiber breakage at the gin and a better end-product.

First Class Cotton

The addition of the micro-gin allows faculty and students at FBRI to work with cotton from the field all the way to producing yarn for different types of fabrics.

Eric Hequet, Horn Professor and chair of the Department for Plant and Soil Science, describes some of the tests that cotton goes through at the Cotton Phenomics Laboratory in the Fiber and Biopolymer Research Institute.

In the commercial world, cotton leaves the gin and goes through an inspection process to determine fiber length and quality. FBRI again mirrors that operation with its Cotton Phenomics Laboratory. The laboratory not only is part of FBRI's research program, but it also works with plant breeders, textile manufacturers and others to test and evaluate fibers, yarns and fabrics.

Cotton is measured and classified by specific physical characteristics such as fiber length, strength, color, and micronaire, the measure of how fine the cotton is. If the fibers are mature enough, the finer the cotton, the higher quality of yarn that can be produced.

“Long, fine, and strong fibers are used to produce fine yarns for more expensive clothing,” Hequet said. “Cotton is a natural fiber so there is a lot of variability. One of our goals is to limit the variability from fiber to fiber.”

Determining fiber properties by hand can take hours, but the automated equipment in the laboratory can tell in a few minutes if the cotton fiber is good enough to send to the textile mill.

Spinning the Future

The final piece of the cotton production cycle is FBRI's Spinning Evaluation Laboratory which operates state-of-the art ring spinning, open-end rotor spinning and a brand new vortex spinning machines. Having different types of spinning technology not only allows FBRI to work with a variety of cotton breeders to know if their new lines are producing the type of fiber that is intended, it also allows students to learn the different technologies.

A history lesson and peek into the future lies behind the reason for the different spinning types. 

In 1997, about 11.3 million bales of U.S. cotton were used by domestic textile manufacturers. Then, Hequet says, the industry collapsed due to higher wages and other economic factors. Today only about 3.3 million bales go to domestic textile manufacturing with the rest – more than 80 percent of U.S. production – being exported, mostly to Asia.

“Traditionally we used open-end spinning in America,” he said. “Rotor spinning can produce a good quality yarn with 1 inch-long cotton and since that was what we were producing it was good. In Asia, particularly China, they use ring spinning. For that you need longer staple cotton and it produces finer yarns for higher end clothing such as shirts for men and women.”

Now salaries are increasing in China and that is creating economic pressure on the Chinese textile manufacturing industry to move to other Asian countries. 

“Ring spinning is very labor intensive and with increasing labor costs, the industry is looking to move on, just as it did from the U.S.,” Hequet said. 

Hequet and his colleagues have a plan that could return some of the textile industry to the U.S. 

FBRI has recently installed a vortex spinning machine. The technology was developed for man-made fibers like polyester and is not cotton friendly. But FBRI's scientists began to question whether a new type of cotton could be developed that would work on the fully-automated vortex machine. 

“We have been looking at some very new, not yet ready for commercialization cotton and I'm very optimistic that we can develop a modified cotton that can fit into this technology,” Hequet said. “We know it is not good economic policy to send 80 percent of our cotton to overseas textile mills.”

While new vortex-ready cotton varieties are years down the road, the research fits into the respected cotton breeding program already underway at Texas Tech. In the mean-time, cotton breeders and students alike benefit from having the latest textile spinning equipment available to test their product and hone marketable job skills.

Gin Specifics

In terms of specific features, Abidi said the micro-gin consists of cotton pre-cleaning equipment such as a hot air cleaner, stick machine and feeder, one 24-saw gin stand to separate the lint from the seeds and an air-jet lint cleaner followed by a single-stage lint cleaner to remove trash particles and contaminants from the lint. The equipment is fully automated and controlled by the same software program used to control modern, full-size cotton gins.

In its current configuration, the micro-gin is capable of processing more than 2,500 pounds of raw cotton per hour.

In addition to FBRI's new micro-gin, the facility has a smaller, 11-saw stand-alone cotton gin with no lint cleaning and a small roller gin for additional research and ginning capacity if needed. The ginning equipment gives Texas Tech agricultural researchers the capacity to process cotton samples from a single boll to a full-sized module if required.