Gasification technology converts trash from cotton gins into energy

Image: Research Communications and Public Relations

Finding new markets for cotton gin trash, wood chips and other waste products could produce more electrical power for a growing global population, an agricultural engineer with Texas A&M AgriLife Research says

Researchers recently demonstrated a biomass-fueled fluidized bed gasifier, which uses cotton gin trash and wood chips to power an electric generator, at Texas A&M University in College Station. Cotton gin trash and other biomass feedstocks are used as fuel to generate heat energy for power production.

The technology has been a focal point for Sergio Capareda, an AgriLife Research agricultural engineer and a professor in the Department of Biological and Agricultural Engineering at Texas A&M.

The fluidized bed gasification system was developed in the 1980s when a patent was issued to Calvin Parnell Jr. and W.A. Lepori, who were both part of the Texas Agricultural Experiment Station, which is now Texas A&M AgriLife Research.

Capareda researched the technology while working on his graduate degree during the late 1980s. Parnell and Lepori were Capareda’s graduate advisors.

Cotton gin trash is produced in abundance at cotton gins across Texas and usually left unused, Capareda said. During harvest season, piles of cotton gin trash can be found at gins throughout the state.

“The process is gasification,” Capareda said. “We limit the amount of air to thermally convert the biomass so the products are combustible gases. These are collectively called synthesis gas. Carbon monoxide and hydrogen, plus a little methane, ethylene, these are a combustible mixture. Combustible in a sense that you can feed it into an internal combustible engine coupled with a generator so you can turn this fuel into electrical power.

“It’s easier said than done, because you have to remove the biochar and all the tar in the syngas before it goes into the engine,” he said. “We have cleaned up the gas very well in this technology.”

The technology converts biomass into electrical power, making it an attractive opportunity for agriculture, the processing industry and electric utilities.