Sharing Expertise and Facilities—NREL Assists DOE and Industry with Biomass Technologies of the Future

July 1, 2004 | Contact media relations

Biomass conversion is as old as the first wood fires humans ever made—to cook food or maybe just to stay warm during a long, cold night. And like everything old, it's new again—and moving in some exciting new directions at NREL. Here, scientists and engineers explore ways to convert plants, plant-derived products, and other biological materials to valuable fuels, chemicals, materials, and electric power. And they help industry by providing expert assistance and by sharing state-of-the-art research, development, and testing facilities.

In the future, "biorefineries" for producing new biomass-based fuels, chemicals, and other products will help to create a major new domestic industry, and they will provide a wide range of valuable products based on renewable resources. They will also allow us to reduce our dependence on imported oil.

National Bioenergy Center
Links Researchers Nationwide

The DOE National Bioenergy Center (NBC) is an "inclusive center without walls." It coordinates and carries out biomass research activities at five DOE laboratories—Argonne National Laboratory, Idaho National Environmental and Engineering Laboratory, Oak Ridge National Laboratory, and Pacific Northwest National Laboratory, and NREL. NREL manages the NBC and is home to the two largest dedicated biomass research facilities, the Alternative Fuels User Facility and the Thermochemical User Facility. Both are available to industry both for collaborative projects with DOE/NREL and for relevant individual industry research projects.

Today, NREL's biomass conversion program is in full gear, producing ethanol fuel from corn stalks, developing gasification processes that use wood chips to generate electricity, and more. John Ashworth and Rafael Nieves, of NREL's Biomass Partnership Development Team, point out that our outstanding biomass R&D facilities are designed to allow DOE and industrial partners of DOE and NREL to develop and prove specific biomass conversion technologies.

Ashworth and Nieves are two primary "point men" in NREL's work with current and potential industry partners. This work on behalf of DOE's Office of the Biomass Program (and NREL) often involves setting up collaborative agreements for major research projects.

"We have world-class user facilities here," Ashworth says. "Making them available to prove or develop industry's energy conversion technologies is one of the most exciting things we do. We're laying the groundwork for a biomass future with our basic research. But where we can help industry bring products to market, the U.S. and the world will see a much more immediate impact."

Although biomass resources are abundant and they supply more energy than other renewable sources, that totals only about 4% of the total U.S. energy supply. However, advanced biomass conversion technologies could change all that.

Why should we develop biomass energy?

Biomass can meet some of our most crucial needs, such as transportation fuels and electric power generation, as we move toward a sustainable future—one in which we make sure that our natural resources are continually being replenished for future use. Renewable energy sources like biomass will thus become more and more important.

Today, ethanol and biodiesel and other potential biomass-based liquid transportation fuels are the only renewable alternatives to imported oil. Plastics and other modern materials that are so big a part of our way of life can also be made from biomass instead of from oil or gas. Combustion or gasification of biomass can sustainably generate a large amount of electrical energy. Biomass gasification can also be used to make liquid transportation fuels from hydrogen-rich syngas. So, the future of biomass energy technologies could be closer than we think.

Where do biomass resources come from—besides trees?

Diagram of a tree trunk cross-section showing that the wood is made up of 15% to 25% lignin, 23% to 32% hemicullulose, and 38% to 50% cellulose.

In our country, the largest resources for biomass energy today are found in industry; they include residues from pulp and paper mills, scrap wood and wood chips from the forest products industry, and agricultural residues. Putting these residues and by-products to work means that much less need for fossil fuels. So, one focus of NREL's research is to find the best ways to gasify or liquefy these materials so that they can be either burned more efficiently or converted to hydrogen, liquid transportation fuels, or other valuable products. The Thermochemical User Facility is an invaluable asset for this research.

Corn is a well-known source of biomass energy. The starch and sugars in corn are used to produce ethanol—already in wide use as a gasoline additive. Starch and sugars are only a small part of most plant biomass, however, and most corn grain is used for animal feed. Also, growing corn is a relatively energy-intensive (and thus expensive) endeavor. So, NREL researchers and partners are investigating good ways to use other parts of the plant as feedstocks for renewable fuels.

The bulk of most plants is made up of cellulose, hemicellulose, and lignin. NREL researchers are working to break down the cellulose and hemicellulose into component sugars—no easy task—so they can be fermented or otherwise processed more easily to make ethanol and other valuable fuels and chemicals. Research like this is carried out in biomass energy conversion research facilities like the Alternative Fuels User Facility.

A pilot plant for developing alternative fuels

Photo of a researcher in the Alternative Fuels User Facility.

The "Mini Pilot Plant" of the Alternative Fuels User Facility allows NREL biomass researchers and industrial partners to test all steps of a complete biomass-to-ethanol process at an economical scale.

NREL biological conversion research in the Alternative Fuels User Facility (AFUF) is at the heart of U.S. efforts to develop cost-effective cellulosic ethanol and other biomass-based chemicals. The AFUF is home to the Bioprocessing Pilot Plant, which can handle up to a ton of feedstock per day, as well as supporting labs. In the 10,000-square-foot pilot plant, NREL and industrial researchers test and develop both partial and complete production processes. Fermentation trials are performed with a wide variety of aerobic and anaerobic microorganisms—including genetically modified strains—in bioreactors with capacities from 160 to 9,000 liters.

Nieves explains, "While the front end of the Bioprocessing Pilot Plant has some very sophisticated capabilities for breaking down cellulose and hemicellulose into their component sugars, the back end has all the equipment a bioprocessing company would need to test an innovative conversion process based on sugars or perhaps on a less challenging feedstock."

Researcher Dan Schell has worked with several industrial partners at the pilot plant. "We can work with industry at all stages of technology development, and at any scale," Schell says. "We are doing some small-scale batch processing now for three of six DOE sugar platform biorefinery projects" The plant can also be reconfigured to perform conventional fermentations from the 30L scale up to 9,000L, as we did during a four-year project with Amoco that processed more than 75 tons of corn fiber (cellulosic residue from corn grain) to ethanol."

A pilot plant for biomass gasification and pyrolysis

Photo of a researcher in front of the Thermochemical Users Facility.

The Thermochemical Users Facility, with its 8-inch-diameter fluidized-bed reactor, can be used to gasify or liquefy (pyrolyze) any biomass feedstock, at up to a half-ton per day. Product synthesis gas can then be tested in a gas turbine, fuel cell, or internal combustion engine and generator or sent to catalytic conversion in a two-inch fluidized bed reactor.

In the state-of-the-art Thermochemical User Facility (TCUF) NREL researchers explore gasification, pyrolysis, and other thermochemical conversion processes developing effective technology for using biomass to produce fuels, chemicals and electricity. The TCUF's half-ton-per-day thermochemical process development unit (TCPDU) is based on a fluidized-bed reactor coupled with a thermal cracker (tubular reactor); this configuration is very flexible and can handle a range of process conditions to reflect product gas compositions of interest to our industrial partners.

Particulate removal, secondary catalytic conversion, and condensation equipment are also available. The TCPDU's modular design allows it to readily accommodate equipment supplied by research partners. Process mass balances are continuously computed from online data. Products and intermediates can be analyzed by several methods, including

  • Gas chromatography
  • Molecular beam mass spectrometry
  • Non-dispersive infrared spectrometry
  • Residual gas analysis
  • Fourier-transform-infrared spectrometry.

Raw synthesis gas and pyrolysis vapors can be upgraded using the fluidized-bed catalytic reforming reactor. The integration of power generation applications with biomass gasification processes can be evaluated, for example, by testing product gas usage in internal combustion engines or microturbines. So can the production of fuels and chemicals in microcatalytic reactors. These capabilities add up to a unique research and development facility for optimizing and integrating thermochemical biomass conversion processes.

R&D collaborations can be small or large, short or long, and anywhere in between, and can handle a wide range of feedstocks. TCUF researcher Dave Dayton recalls a recent gasification project with a research company that resulted in patent applications for a way to make use of agricultural residues that are now posing a major disposal problem. TCUF manager Steve Phillips adds that the facility was ideal for work with a major wet-mill corn processor interested in pyrolysis of corn fiber. And several parties joined DOE recently to investigate ways to process peanut shells (yes, peanut shells!) to produce hydrogen.

How can industry use these facilities?

Both the AFUF and the TCUF are named user facilities with good reason. Industrial companies and academic researchers can use NREL's Bioprocessing and Thermochemical Pilot Plants in collaborative projects under various DOE and NREL technology partnership agreements. They can also develop or prove their technology as part of a contractual arrangement. NREL researchers have years of experience investigating biomass conversion processes. The combination of technical experience and a wealth of research and analytical equipment position NREL to successfully and cost-effectively help to develop a biomass industry through strategic industrial collaborations and partnerships.

Recently developed service agreements also allow us to provide assistance with smaller projects for developing biomass conversion technologies. Ashworth says, "We are open to collaborative work of any kind that advances the goals of the Biomass Program. We're particularly interested in working on large amounts of readily available feedstocks with the potential to make a major contribution to the biomass economy, and in working with partners who have substantial technical know-how, to exchange knowledge and expertise."

To learn more about specific biomass facilities and capabilities, or to explore opportunities for collaborations under NREL's Biomass Program, contact Dr. John Ashworth, (303) 384-6858.

For Further Reading

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— Howard Brown