The Cutting Edge of Corn Stover and Switchgrass Supply: A Comprehensive Feedstock Solution

(U.S. Department of Energy) Supplying high-quality feedstock for use in a broad range of sustainable conversion processes to produce advanced biofuels is a complex, multi-step process. Each step in the feedstock supply and logistics chain—from harvesting, preparing, and packaging, to loading and transporting—presents a unique set of challenges and barriers to ultimately achieving a streamlined process that will allow for the cost-competitive production of domestic, renewable biofuels and bioproducts. The Bioenergy Technologies Office (BETO) awarded five grants to help fund demonstration projects that are working to establish a comprehensive approach for overcoming barriers and providing a consistent, high-quality, affordable feedstock supply.

FDC Enterprises (FDCE) was one of the five recipients of the competitively awarded BETO high-tonnage feedstock grants. FDCE's project successfully coordinated the efforts of several equipment manufacturers, including Kelderman Manufacturing, MacDon Inc., and Allied Freeman—as well as several other project partners—to design, build, and demonstrate a state-of-the-art, three-piece prototype of a harvesting equipment system. The prototype system addresses some of the key challenges in the feedstock supply chain, including effective time management and equipment and personnel use.

The current process of collecting, preparing, loading, and transporting feedstock can be time consuming and costly; multiple pieces of equipment are often needed to complete just one step in the process, requiring valuable labor and machine time and effort to operate. Meanwhile, every other step hinges on the one before it—nothing can be packaged if it hasn’t been harvested and prepared. This situation can result in a significant amount of waiting time for equipment operators, which drives up labor and operations costs and lowers the overall efficiency of operations. FDCE’s system prototype streamlines each step of the collection, packaging, loading, and distribution process to save both time and money. The system features components designed and built by each of the manufacturing companies in the project grant, which were later combined and tested on acreage made available by many different private producers and partners in the project, including Star Seed Inc., Mendel Biotechnology, and the Noble Foundation. MacDon Inc., of Kansas City, Missouri, created and modified a cutting header capable of single-pass harvesting of a variety of high-yielding standing grass crops; Allied Freeman, headquartered in Brawley, California, supplied original balers for modification; and Kelderman Manufacturing, of Oskaloosa, Iowa, modified the baler and designed and built the bale picking truck and self-loading trailer.

The equipment system consists of three parts, of which the latter two are completely novel and designed from the bottom up: (1) a single-pass, self-propelled baler; (2) a bale picking truck (BPT); and (3) a self-loading trailer (SLT). In contrast, traditional harvesting equipment requires two to five passes to cut and gather a crop with one or more cutting and windrowing machines, a baler, a machine to move and stack the bales, and one or more forklifts to transfer bales onto a flatbed truck or trailer for transport. Each of these machines requires at least one operator. Thus, with the minimum amount of equipment in a conventional process, the initial purchase and daily operational costs of a complete feedstock supply system can be significant. By creating three multi-tasking, mutually compatible pieces of equipment, FDCE's system enables a faster, streamlined solution to the difficult process while reducing investments and daily costs as much as possible.

The baler—a modified version of a commercially available Allied Freeman baler—is used to make one pass through the acreage to collect feedstock, precondition it, and package the material into large square bales at high density. The single pass baler is a significant improvement over traditional baling equipment, which requires multiple passes. Interchangeable headers mounted on the front of the baler allow it to either rake corn stover on the ground into rows or cut a standing crop like switchgrass, which is then arranged into rows for simultaneous pickup. The material is then self-fed into a chamber within the baler, unless the material requires drying. Once the bales are formed and lowered to the ground in pairs, the BPT follows to collect and neatly stack bales in packs of six. While it continues to pick up and stack more bales, the BPT simultaneously transfers the existing packs onto a flatbed carrying surface, which is capable of holding six or seven packs. By performing these two tasks at one time, the BPT is accomplishing what once required two or more pieces of equipment, numerous trips around the field, and far more time.

Once the BPT flatbed is full of packs, it moves to the edge of the field where the assembled stack of bales can be unloaded as one single unit onto the ground to await later pickup, or transferred directly onto the SLT for over-the-road transport to a biorefinery. The BPT can move the entire stack of bales onto the SLT in about five minutes using a single operator instead of two to three operators, which would take approximately 45 minutes using forklifts and securing methods. Once the SLT is completely full, a driver transports the load to a biorefinery or other end user. At the delivery site, the SLT can self-unload the bales onto the ground in the storage yard, or load the bales into the refinery's in-feed mechanism for immediate use—all within a shorter period of process time than traditional unloading equipment.

In addition to the impressive demonstration success of the equipment, the self-propelled baler was prominently featured at the World Ag Expo in Tulare, California, in early February of this year. The bale picking truck was also displayed at the International Biomass Conference and Expo in Denver, Colorado, in April 2012. All three pieces of equipment are available for lease or partnering agreement through Feedstox, a subsidiary of the Kansas Alliance for Biorefining and Bioenergy. The innovative design, extensive development and demonstration, and eventual commercialization of the system are a major success for BETO. Thanks to the hard work of FDCE and its partners, their efforts support the Office’s sustained commitment to making biofuels an affordable, reliable, domestic alternative to fossil fuels. READ MORE