14 research outputs found
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Single Pass Multi-component Harvester
Abstract. In order to meet the U. S. government’s goal of supplementing the energy available from petroleum by increasing the production of energy from renewable resources, increased production of bioenergy has become one of the new goals of the United States government and our society. U.S. Executive Orders and new Federal Legislation have mandated changes in government procedures and caused reorganizations within the government to support these goals. The Biomass Research and Development Initiative is a multi-agency effort to coordinate and accelerate all U.S. Federal biobased products and bioenergy research and development. The Initiative is managed by the National Biomass Coordination Office, which is staffed by both the DOE and the USDA. One of the most readily available sources of biomass from which to produce bioenergy is an agricultural crop residue, of which straw from small grains is the most feasible residue with which to start. For the straw residue to be used its collection must be energy efficient and its removal must not impact the sustainability of the growing environment. In addition, its collection must be economically advantageous to the producer. To do all that, a single pass multi-component harvester system is most desirable. Results from our first prototype suggest that current combines probably do adequate threshing and that a separate chassis can be developed that does additional separation and that is economically feasible
Engineering, nutrient removal, and feedstock conversion evaluations of four corn stover harvest scenarios
Crop residue has been identified as a near-term source of biomass for renewable fuel, heat, power, chemicals and other bio-materials. A prototype one-pass harvest system was used to collect residue samples from a corn (Zea mays L.) field near Ames, IA. Four harvest scenarios (low cut, high-cut top, high-cut bottom, and normal cut) were evaluated and are expressed as collected stover harvest indices (CSHI). High-cut top and high-cut bottom samples were obtained from the same plot in separate operations. Chemical composition, dilute acid pretreatment response, ethanol conversion yield and efficiency, and thermochemical conversion for each scenario were determined. Mean grain yield in this study (10.1 Mg ha−1 dry weight) was representative of the average yield (10.0 Mg ha−1) for the area (Story County, IA) and year (2005). The four harvest scenarios removed 6.7, 4.9, 1.7, and 5.1 Mg ha−1 of dry matter, respectively, or 0.60 for low cut, 0.66 for normal cut, and 0.61 for the total high-cut (top+bottom) scenarios when expressed as CSHI values. The macro-nutrient replacement value for the normal harvest scenario was 11.27 Mg−1. Harvesting stalk bottoms increased stover water content, risk of combine damage, estimated transportation costs, and left insufficient soil cover, while also producing a problematic feedstock. These preliminary results indicate harvesting stover (including the cobs) at a height of approximately 40 cm would be best for farmers and ethanol producers because of faster harvest speed and higher quality ethanol feedstock
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Temporal Changes in the Spatial Variability of Soil Nutrients
This paper reports the temporal changes in the spatial variability of soil nutrient concentrations across a field during the growing season, over a four-year period. This study is part of the Site-Specific Technologies for Agriculture (SST4Ag) precision farming research project at the INEEL. Uniform fertilization did not produce a uniform increase in fertility. During the growing season, several of the nutrients and micronutrients showed increases in concentration although no additional fertilization had occurred. Potato plant uptake did not explain all of these changes. Some soil micronutrient concentrations increased above levels considered detrimental to potatoes, but the plants did not show the effects in reduced yield. All the nutrients measured changed between the last sampling in the fall and the first sampling the next spring prior to fertilization. The soil microbial community may play a major role in the temporal changes in the spatial variability of soil nutrient concentrations. These temporal changes suggest potential impact when determining fertilizer recommendations, and when evaluating the results of spatially varying fertilizer application
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Physical Separation of Straw Stem Components to Reduce Silica
In this paper, we describe ongoing efforts to solve challenges to using straw for bioenergy and bioproducts. Among these, silica in straw forms a low-melting eutectic with potassium, causing slag deposits, and chlorides cause corrosion beneath the deposits. Straw consists principally of stems, leaves, sheaths, nodes, awns, and chaff. Leaves and sheaths are higher in silica, while chaff, leaves and nodes are the primary source of fines. Our approach to reducing silica is to selectively harvest the straw stems using an in-field physical separation, leaving the remaining components in the field to build soil organic matter and contribute soil nutrients
Engineering High-Fidelity Residue Separations for Selective Harvest
Composition and pretreatment studies of corn stover and wheat stover anatomical fractions clearly show that some corn and wheat stover anatomical fractions are of higher value than others as a biofeedstock. This premise, along with soil sustainability and erosion control concerns, provides the motivation for the selective harvest concept for separating and collecting the higher value residue fractions in a combine during grain harvest. This study recognizes the analysis of anatomical fractions as theoretical feedstock quality targets, but not as practical targets for developing selective harvest technologies. Rather, practical quality targets were established that identified the residue separation requirements of a selective harvest combine. Data are presented that shows that a current grain combine is not capable of achieving the fidelity of residue fractionation established by the performance targets. However, using a virtual engineering approach, based on an understanding of the fluid dynamics of the air stream separation, the separation fidelity can be significantly improved without significant changes to the harvester design. A virtual engineering model of a grain combine was developed and used to perform simulations of the residue separator performance. The engineered residue separator was then built into a selective harvest test combine, and tests performed to evaluate the separation fidelity. Field tests were run both with and without the residue separator installed in the test combine, and the chaff and straw residue streams were collected during harvest of Challis soft white spring wheat. The separation fidelity accomplished both with and without the residue separator was quantified by laboratory screening analysis. The screening results showed that the engineered baffle separator did a remarkable job of effecting high-fidelity separation of the straw and chaff residue streams, improving the chaff stream purity and increasing the straw stream yield
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The Single Pass Multi-component Harvester
The authors are solely responsible for the content of this technical presentation. The technical presentation does not necessarily reflect the official position of the American Society of Agricultural Engineers (ASAE), and its printing and distribution does not constitute an endorsement of views which may be expressed. Technical presentations are not subject to the formal peer review process by ASAE editorial committees; therefore, they are not to be presented as refereed publications. Citation of this work should state that it is from an ASAE meeting paper. EXAMPLE: Author's Last Name, Initials. 2004. Title of Presentation. ASAE Paper No. 04xxxx. St. Joseph, Mich.: ASAE. For information about securing permission to reprint or reproduce a technical presentation, please contact ASAE at [email protected] or 269-429-0300 (2950 Niles Road, St. Joseph, MI 49085-9659 USA). Abstract. In order to meet the U. S. government’s goal of supplementing the energy available from petroleum by increasing the production of energy from renewable resources, increased production of bioenergy has become one of the new goals of the United States government and our society. U.S. Executive Orders and new Federal Legislation have mandated changes in government procedures and caused reorganizations within the government to support these goals. The Biomass Research and Development Initiative is a multi-agency effort to coordinate and accelerate all U.S. Federal biobased products and bioenergy research and development. The Initiative is managed by the National Biomass Coordination Office, which is staffed by both the DOE and the USDA. One of the most readily available sources of biomass from which to produce bioenergy is an agricultural crop residue, of which straw from small grains is the most feasible residue with which to start. For the straw residue to be used its collection must be energy efficient and its removal must not impact the sustainability of the growing environment. In addition, its collection must be economically advantageous to the producer. To do all that, a single pass multi-component harvester system is most desirable. Results from our first prototype suggest that current combines probably do adequate threshing and that a separate chassis can be developed that does additional separation and that is economically feasible
A Single Pass Multi-component Harvester for Small Grains
Abstract. In order to meet the U. S. government's goal of supplementing the energy available from petroleum by increasing the production of energy from renewable resources, increased production of bioenergy has become one of the new goals of th
From Prediction to Prescription: Intelligent Decision Support for Variable Rate Fertilization
We describe the use of machine learning methods in the analysis of spatial soil fertility, soil physical characteristics, and yield data, with a particular objective of determining local (field- to farm-scale) crop response patterns. For effective prescriptive use, the output of these tools is augmented with economic data and operational constraints, and recast as a rulebased decision support tool to maximize economic return in variable rate fertilization systems. We describe some of the practical issues addressed in development of one such system, including data preparation, adaptation of regression tree output for use in a rule-based expert system, and incorporation of real-world limits on system recommendations. Results from various field trials of this system are summarized
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Roadmap for Agriculture Biomass Feedstock Supply in the United States
The Biomass Research and Development Technical Advisory Committee established a goal that biomass will supply 5% of the nation’s power, 20% of its transportation fuels, and 25% of its chemicals by 2030. These combined goals are approximately equivalent to 30% of the country’s current petroleum consumption. The benefits of a robust biorefinery industry supplying this amount of domestically produced power, fuels, and products are considerable, including decreased demand for imported oil, revenue to the depressed agricultural industry, and revitalized rural economies. A consistent supply of highquality, low-cost feedstock is vital to achieving this goal. This biomass roadmap defines the research and development (R&D) path to supplying the feedstock needs of the biorefinery and to achieving the important national goals set for biomass. To meet these goals, the biorefinery industry must be more sustainable than the systems it will replace. Sustainability hinges on the economic profitability of all participants, on environmental impact of every step in the process, and on social impact of the product and its production. In early 2003, a series of colloquies were held to define and prioritize the R&D needs for supplying feedstock to the biorefinery in a sustainable manner. These colloquies involved participants and stakeholders in the feedstock supply chain, including growers, transporters, equipment manufacturers, and processors as well as environmental groups and others with a vested interest in ensuring the sustainability of the biorefinery. From this series of colloquies, four high-level strategic goals were set for the feedstock area: • Biomass Availability – By 2030, 1 billion dry tons of lignocellulosic feedstock is needed annually to achieve the power, fuel, and chemical production goals set by the Biomass Research and Development Technology Advisory Production Committee • Sustainability – Production and use of the 1 billion dry tons annually must be accomplished in a sustainable manner • Feedstock Infrastructure – An integrated feedstock supply system must be developed and implemented that can serve the feedstock needs of the biorefinery at the cost, quality, and consistency of the set targets • System Profitability – Economic profitability and sustainability need to be ensured for all required participants in the feedstock supply system. For each step in the biomass supply process—production, harvesting and collection, storage, preprocessing, system integration, and transportation—this roadmap addresses the current technical situations, performance targets, technical barriers, R&D needs, and R&D priorities to overcome technical barriers and achieve performance targets. Crop residue biomass is an attractive starting feedstock, which shows the best near-term promise as a biorefinery feedstock. Because crop residue is a by-product of grain production, it is an abundant, underutilized, and low cost biomass resource. Corn stover and cereal straw are the two most abundant crop residues available in the United States. Therefore, this roadmap focuses primarily on the R&D needed for using these biomass sources as viable biorefinery feedstocks. However, achieving the goal of 1 billion dry tons of lignocellulosic feedstock will require the use of other biomass sources such as dedicated energy crops. In the long term, the R&D needs identified in this roadmap will need to accommodate these other sources of biomass as well