Turning ‘leftovers’ into power

May 27, 2011
by WLJ
Turning ‘leftovers’ into power

Manure, grain and stalks all have a value as a biomass or source of energy.

Texas AgriLife Research in Amarillo, TX, is trying to determine just how much “bang for the buck” there might be in these agriculture leftovers.

Brent Auvermann, Agri- Life Research environmental systems specialist, said in an effort to serve the livestock industry and grain producers in this region, two facilities have been added recently at the Agri- Life Research farm near Bushland, TX—a biomass characterization and drying facility.

“We’ve added to our instrumentation as we’ve expanded our facilities,” Auvermann said. “We now have a bomb calorimeter, which burns small samples of the biomass and measures the amount of heat liberated by the combustion.”

This tells the research team the amount of fuel energy contained in a pound of the material using the same instrumentation used by the commercial industry to determine coal’s heating value, he said.

The research has a multitude of purposes, in addition to estimating the fuel value of the biomass source, Auvermann said.

“We are using this to figure out how to manage the production of these biomass sources to ensure high-quality material,” he said. “If biofuels are ever going to replace a significant propor tion of our fossil-fuel consumptions, we need to support the development of a market-based incentive framework for producing that high-quality product.”

Auvermann said in the U.S., “market incentives equal both jobs and environmental progress.”

Another benefit to this research is improving the environment by making sure the waste materials from agriculture can and are used as a biofuel, he said. That includes feedlot and dairy manure, grain sorghum, corn grain and crop residues, such as cotton gin trash or corn stover.

“The same management practices that improve manure quality for fuel also improve the fertilizer quality and help reduce air emissions,” he said.

The addition of a nearinfrared spectrometer at the facility will help the science world determine what a quality load of manure looks like in the truck or on the feedlot surface, Auvermann said.

“A quick, handheld method will enable a potential customer to determine whether a truckload of manure is fuel-grade, fertilizer-grade or low-grade material,” he said.

Two other pieces of equipment housed in the new biomass characteriza tion

facility are a muffle furnace, which allows the ash content or noncombustible parts to be measured, and a drying oven, which allows the water content of a biomass source to be measured. Water and dirt are manure contaminants, he said.

The facilities were built in part through grants from the U.S. Department of Energy, USDA and the Texas Legislature.

“Biomass energy isn’t going away, and we need to know how to make it, how to make it well, and how to improve its value to those who make it and use it,” Auvermann said.

Feedlot manure is primarily a substitute for natural gas or coal, or it can be converted indirectly to ethanol, he said. The highest-quality manure is roughly equivalent to lignite coal and about twothirds the full energy value of coal from Wyoming’s Powder River Basin.

“If we can provide cheap, fast and accurate tools to measure feedstock quality, and if we can scientifically document the techniques that generate the highest quality feedstocks, we will have moved the biomass energy industry a little closer to the mainstream marketplace,” Auvermann said.