TVA Fertilizer Research

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Now showing 1 - 5 of 47
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    Performance of Dry Fertilizer Applicators
    (1986-12-01) Broder, Michael F.
    The introduction of bulk blending of granular fertilizer in the late 1940s led to the rise of custom bulk spreading and the popularity of spinner spreader trucks in the United States. However, the nonuniform application of fertilizers by spinner spreaders has created an opportunity for liquid fertilizer dealers. In recent years, equipment manufacturers have developed boomed dry spreaders that claim to provide the same accuracy and uniformity as liquid sprayers. This paper presents data comparing the performance of boomed and spinner spreaders, focusing on aspects such as uniformity, rate accuracy, range of application rates, ease of adjustment and calibration, and nutrient application uniformity. The data confirms that no single applicator excels in all aspects of performance. The paper also discusses machine designs, spread patterns, rate accuracy, the effect of speed on rate accuracy, and the segregation tendencies of different applicators.
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    Effect of Granule Size on Application
    (1983-10) Balay, Hubert L.; Broder, Michael F.
    This study investigates the effect of granule size on the application of dry fertilizer using spinner spreaders, which are commonly used in the United States for broadcasting fertilizer. Previous research has emphasized the importance of particle size in maintaining uniform distribution within blends. However, the focus has been on smaller particles, discouraging using larger materials. This paper explores the advantages of broadcasting materials larger than typical granular products and examines the impact on spread patterns. The literature review reveals that particle size significantly influences the segregation of raw materials in blends. Small particles travel a shorter distance from the spinning discs than large particles, affecting the distribution pattern. Studies have also shown that irregularly shaped particles travel less distance than spherical particles due to their larger drag coefficients. However, recent research suggests that while median particle size is crucial, size variability has little effect on the spread pattern. The study conducts field spreading tests using a double-spinner spreader and a high-flotation applicator with a single spinner. Three different sizes of urea granules are used, with similar density, shape, and surface roughness. The spread patterns are analyzed using a computer program, and various spinner and chute adjustments are tested to determine the optimal settings. Results demonstrate that larger granules can be broadcasted more effectively when placed nearer to the centers of double spinners. Swath widths increase significantly, with improvements of up to 30 feet observed. The study also reveals that larger granules produce less dust and are less prone to drifting, making them advantageous in reducing environmental concerns.
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    Quality Control of Liquids and Suspensions
    (1984-12) Balay, Hubert L.
    The analysis and quality control of solid fertilizers has been extensively studied. In contrast, liquid and suspension fertilizers have often been assumed to be less prone to quality control issues due to their relatively homogeneous nature. However, control officials' reports indicate that such assumptions are unfounded. This publication investigates the impurities in raw materials, particularly phosphate sources, used in fluid fertilizer production and highlights their contribution to quality control challenges. The study draws upon research conducted by the Tennessee Valley Authority (TVA), revealing the presence of insoluble compounds derived from impurities in phosphate rock and wet-process phosphoric acid production in raw materials used for fluid fertilizer production. A profound understanding of the fundamental principles underlying liquid and suspension fertilizers is crucial to establish an effective quality control program. The publication clarifies the significance of a solubility curve representing the relative solubility of ammonium phosphates during fertilization. Furthermore, it emphasizes the importance of selecting appropriate potash grades for suspensions, considering criteria such as size specifications and impurity content. The publication also provides insights into preparing carriers for suspensions, focusing on the commonly used attapulgite clay as a suspending agent. It highlights the necessity of properly shearing and gelling the clay to prevent settling and crystal growth in suspensions. The recommended shearing process involves multiple passes through a centrifugal pump, ensuring optimal orientation of clay particles. Additionally, the publication explores the electrical charge characteristics of attapulgite clay, which contribute to its ability to prevent solids from settling. Sampling techniques for fluid fertilizers are addressed to ensure accurate chemical analysis. Proper sampling procedures are outlined, including the importance of recirculating the fertilizer through the pump to obtain representative samples. The publication suggests determining the optimal recirculation time experimentally or with assistance from control officials, ensuring reliable and consistent sampling.
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    Developments in Fertilizer Technology and Application Techniques
    (1988-12) Broder, Michael F.; Mann, Horace C.; Culp, John E.
    This material provides an overview of the National Fertilizer Development Center (NFDC), a key Tennessee Valley Authority (TVA) program dedicated to fertilizer research and development. Established in 1933, TVA aimed to foster the growth of the Tennessee Valley region and promote public-private cooperation in developmental programs. The NFDC, located in Muscle Shoals, Alabama, is the nation's only comprehensive fertilizer research and development program. The NFDC's primary objectives are to generate new technologies and products related to fertilizers, improve fertilizer use efficiency, and prevent environmental damage caused by fertilizer production and application. The center conducts basic research, developmental activities, and national technology transfer programs in collaboration with the fertilizer industry, land-grant universities, and farmers. It has the necessary facilities to develop and test new technologies, including laboratories, pilot plants, prototype production facilities, and greenhouses. The paper also highlights several recent and ongoing developments in fertilizer manufacturing. One notable innovation is the production of urea-nitric phosphate (UNP), a solid fertilizer with potential economic advantages over traditional methods. The NFDC's falling curtain-evaporative cooling process is also discussed, enabling urea granulation with superior product quality and low energy consumption. Additionally, the use of calcium lignosulfonate as a conditioning agent for granular urea, replacing formaldehyde, is explored due to its environmental safety and cost-effectiveness. The material further outlines advancements in sulfur-coated urea, nitrogen-sulfur fluid fertilizers, and phosphate-based products, including ammonium polyphosphate and urea phosphate. It highlights the NFDC's efforts to develop cost-effective fertilizers while considering environmental concerns and using lower-grade phosphate ores. It concludes by discussing recent progress in fertilizer application technology, including automatic rate controllers and fuel efficiency improvements in custom application equipment.
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    Process and Product Considerations of Fluid Lime
    (1980-08-26) Balay, Hubert L.; Salladay, David G.
    This material provides an overview of fluid lime's process and product considerations, focusing on its various applications and the challenges associated with its production and use. It highlights the widespread use of limestone in construction, agriculture, metallurgy, and chemical processes. The report discusses the importance of limestone in agriculture for raising soil pH and improving crop yields. It emphasizes the significance of limestone's particle size and chemical composition in determining its effectiveness in soil neutralization. The publication further explores the concept of fluid lime, which involves applying finely-ground limestone as a suspension, thereby eliminating dust during handling and promoting rapid reaction in the soil. It describes the equipment and mixing procedures involved in producing limestone suspensions, including the use of combination mixing-storage systems to address storage and handling issues. The document also explores the potential use of byproduct sources of limestone, such as precipitated flue dust from cement plants and waste materials from sugar refining and pulp and paper industries, as alternative raw materials for fluid lime suspensions.