TVA Fertilizer Research
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Browsing TVA Fertilizer Research by Subject "Ammonia"
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- ItemRecent Developments in Granulation I(1965-11) Achorn, Frank P.; Lewis, J.S. Jr.This document provides an overview of recent advancements in granulation technology, specifically focusing on granulation plants and their conversion processes. The granulation industry has witnessed an increase in the number of plants as companies previously producing pulverized mixtures have switched to batch granulation methods. This transition involves modifying batch mixers, installing ammonia and acid distributors, and utilizing rotary coolers for product cooling. Producers with medium-sized granulation plants have adopted pre neutralizers and scrubbers to enhance their production capabilities, leading to the manufacturing of diammonium phosphate granules and higher annual production volumes. The shift towards complete-grade handling stations has been observed among these companies. Additionally, some producers have transformed their batch ammoniators into continuous ammoniator-granulators to meet higher production demands. Various strategies have been employed to improve the efficiency and performance of granulation equipment. Operators have experimented with different materials for sparger pipes, with stainless steel and Hastelloy being preferred due to their longer lifespan and improved distribution of ammonia and acid within the granulator. Removing internal rings in ammoniator-granulators has been found to have no negative impact on granulation efficiency, while longer distributors have helped minimize nitrogen loss during the process. Several techniques have been implemented to prevent material caking, including rubber linings, flaps, knockers, and oscillating or spiral scrapers. These mechanisms effectively remove buildup from the walls of the ammoniator-granulator, ensuring smooth operation. Furthermore, a patented device for cleaning and positioning sparger bars has been introduced, enabling their rotation without equipment shutdown and facilitating maintenance. Integrating pre-neutralizers and scrubbers have allowed manufacturers to utilize larger quantities of phosphoric acid and ammonia to produce diammonium phosphate grades. The TVA process, involving partial ammoniation in a pre-neutralizer and complete ammoniation in the ammoniator-granulator, has shown promising results with high ammoniation levels and increased fluidity. This process allows for significant phosphoric acid consumption, resulting in high-quality fertilizers. Bulk handling stations have gained popularity among companies producing high-analysis grades, such as 8-24-2, 10-20-30, 12-24-24, and 20-10-10. These stations optimize transportation costs and enable the marketing of products over longer distances. Typical bulk handling stations consist of storage buildings with multiple bins or elevated storage tanks, utilizing conveyor systems for material unloading, storage, and loading onto bulk trucks. Cost studies indicate that constructing bulk handling stations alongside granulation plants is a competitive alternative to bulk blending, especially for high-analysis grades. However, the economic viability of this system relies on a high material movement, preferably exceeding 70,000 tons. At this scale, the cost-effectiveness of granulation with bulk handling stations approaches that of bulk blending. Collapse
- ItemRecent Developments in Granulation II(1967-09) Achorn, Frank P.This material discusses developments in granulation techniques in the fertilizer industry, presented by Frank P. Achorn at the Seminar for Latin American Fertilizer Executives in September 1967. The number of granulation plants in the United States and abroad has been steadily increasing. Many companies that previously produced pulverized mixtures have converted their batch ammoniators to granulators to produce granular products. Large-scale granulation plants have incorporated pre-neutralizers to manufacture diammonium phosphate grades. The Tennessee Valley Authority (TVA) ammoniator-granulator has been widely utilized for the production of diammonium phosphate and triple superphosphate grades by major granular fertilizer producers. These products are often marketed through blending plants, where they are mixed with potash to create different nitrogen, P₂O₅, and K₂O ratios. The conversion of small pulverized-mix plants into granulation plants has involved modifying the batch mixers by installing ammonia and acid distributors. Sketches and flow diagrams illustrate these modifications and the operation of batch granulation plants. Rotary coolers are used to rapidly cool the granular products, with some producers choosing to screen and recirculate the cooled material to the granulator for improved quality control. Certain companies have further converted their ammoniators into continuous granulators by enlarging the discharge and operating continuously. However, due to production limitations, some companies plan to construct conventional ammoniator-granulation plants to achieve higher production rates.
- ItemThe Spectrum of Fluid Fertilizers(1967-02) Achorn, Frank P.This material provides an overview of the development and adoption of liquid fertilizers in the United States. The document highlights the growth of the liquid fertilizer industry, particularly nitrogen solutions, and ammonia, which now supply a significant portion of the total nutrient consumption. The use of superphosphoric acid and its role in sequestering impurities in wet-process phosphoric acid is discussed. The document further explores the different types of liquid fertilizer production plants, including liquid hot-mix and liquid cold-mix plants. The potential of suspension fertilizers, their production process, and the benefits of using a base suspension with gelling agents are also addressed. Overall, this document offers valuable insights into the evolution and utilization of fluid fertilizers in agricultural practices.