Feedstocks May Help Guarantee Biofuel Supply Chain

New project is also expected to develop and demonstrate a state-of-the-art biomass processing.

Pilot-scale biomass pelleting equipment

Gasoline and other petroleum-based products are affordable today, but such was not the case just a few short years ago, and higher prices will likely return in the future.

That's one reason why scientists with the University of Tennessee Center for Renewable Carbon (CRC) continue efforts to develop renewable and cost-competitive biofuels and bio-based products that can be useful for society and to advance rural economies.

The CRC is the lead institution in a $4 million study funded by the U.S. Department of Energy Bioenergy Technologies Office that will allow the CRC and its partners to explore in greater detail some feedstock supply and logistical issues. Partners in the broad-based effort include Auburn University, North Carolina State University and the Idaho National Laboratory.

Industry partners Genera Energy, PerkinElmer and Herty Advanced Materials Development Center are all providing guidance regarding the commercial implementation of the harvesting, pre-preprocessing and refining technologies.

"Biorefineries need a guaranteed supply chain, and the research seeks to determine if blending feedstocks could play a role in increasing the performance of feedstock available to biorefineries while lowering the cost," said Tim Rials, project leader and CRC director.

The project is also expected to develop and demonstrate a state-of-the-art biomass processing depot to reduce sources of variation along the supply chain of multiple, high-impact biomass sources and to deliver a consistent feedstock optimized for conversion in different platforms.

Rials says the synergy between the partners and the research infrastructure established by this large project is key to long-term success. "Developing biofuels and bio-based products requires solving a complicated set of scientific and technical problems. You have to be able to grow the different feedstocks efficiently, then harvest and deliver them to biorefineries at a cost that will make it worthwhile to industry to transform the feedstocks into usable industrial products and affordable fuels. Each step from production to harvesting to transportation to chemical conversion presents its own unique challenges, and opportunities to improve the overall system."

Genera Energy will contribute expertise related to feedstock pre-processing and analyses, including spectroscopic monitoring, at its Vonore, Tenn., facility - the country's largest and most comprehensive industrial biomass management and processing facility. Genera will employ real-time feedstock monitoring technology to improve feedstock pre-processing. This will enable processing optimization, both in cost and energy consumption, along with an increased dataset on feedstock specifications that reduces variability for the end user. This step will help guarantee potential biorefineries and bioproducts manufacturers will have a consistent and uniform feedstock from which they can refine fuels and other products.

"One barrier to the development of viable biorefineries is the availability of a constant and consistent supply of uniform materials for use in their refineries," said Peter Muller, of PerkinElmer. "We expect the spectroscopic monitoring will help us blend different feedstocks to produce an acceptable feedstock in sufficient quantities to support an industry."

Genera is also providing milled materials, predominantly switchgrass and southern pine generated by the region's forest products industry, to the other project partners for blending, pelleting and analyses. "The ability to utilize these and other feedstocks in multiple conversion technologies is critical to the success of the biobased industry," noted Sam Jackson, Genera's vice president of business development. "Better understanding the milling properties and blending capabilities of feedstocks allows users to mitigate any issues with biomass composition and their impacts on specific processes," he continued.

Idaho National Laboratory's role will be to develop models that can predict biomass properties that are important in conversion processes in the production of liquid fuels and biobased chemicals. This involves the demonstration of innovative sensing technologies and the development of feedstock blending and densification technologies that can reduce the cost of biomass.

"Developing economic solutions for integrating woody residue and energy crops can be an incredible low-cost approach to supplying high-quality feedstock for biorefineries and will be key to getting the biobased economy out of the gate," said Ali Omar, project lead with Herty Advanced Materials Development Center at Georgia Southern University.

With the goal of producing feedstock at a targeted cost of $80 per dry ton or below, the development team is working to find the optimal feedstock available from a combination of southern softwood residuals and purpose-grown energy crops, such as switchgrass and hybrid poplar. Analyzing feedstock quality in terms of quality metrics like ash levels and lignin content will be critical given their promise as low-cost feedstock options.

"What is exciting about this project is that the information developed from this national project will not only have a direct impact on biorefinery developers, but will also help traditional wood products companies improve their operations through the utilization of low-value wood supplies," said Steve Taylor, project lead at Auburn University.

Rials says the industry has made great strides in the last 10 years, including in feedstock production, but there remain opportunities to further improve the system. "This collaboration will take us one step closer to a valuable new biobased economy," he said. "The goal continues to be a biobased economy as opposed to a petroleum-based economy, with affordable, renewable fuels and products."