Ammonium liquid fertilizer manufacture

As previously mentioned, fertilizer manufacturing may create problems within all environmental media, that is, air pollution, water pollution, and solid wastes disposal difficulties. In particular, the liquid waste effluents generated from phosphate and mixed and blend fertilizer production streams originate from a variety of sources and may be summarized [17,27] as follows (a) ammonia-bearing wastes from ammonia production (b) ammonium salts such as... 

Liquid ammonium phosphate fertilizers Ammonium polyphosphates can be manufactured from phosphoric acids containing either high or low concentrations of poly-phosphoric acid, or from orthophosphoric acid solutions. 

Most of us are familiar with the hquid form of ammonia known as ammonium hydroxide (NH OH), a colorless liquid that, with its strong odor, is irritating to the eyes and potentially harmful to the moist mouth and nose, throat, and lungs if its vapors are breathed. Weak solutions of NH OH are ingredients in household cleaning ammonia. Concentrated ammonium hydroxide has many industrial uses, including the manufacture of rayon, fertilizers, refrigerants, rubber, pharmaceuticals, soaps lubricants, inks, explosives, and household cleaners. 

The single largest use of ammonia is its direct apphcation as fertdizer, and in the manufacture of ammonium fertilizers that have increased world food production dramatically. Such ammonia-based fertilizers are now the primary source of nitrogen in farm soils. Ammonia also is used in the manufacture of nitric acid, synthetic fibers, plastics, explosives and miscellaneous ammonium salts. Liquid ammonia is used as a solvent for many inorganic reactions in non-aqueous phase. Other apphcations include synthesis of amines and imines as a fluid for supercritical fluid extraction and chromatography and as a reference standard in i N-NMR. 

Some nitric acid is used for the manufacture of explosives and chemicals, but much is converted on-site to the potentially explosive high nitrogen fertilizer ammonium nitrate (Section 2.11). Ammonia gas from the Haber plant is absorbed in aqueous HN03, and the NH4N03 solution is evaporated to a liquid melt (< 8% H20) for crystallization, but care must be taken to keep the pH of the solution above about 4.5 and to exclude any material (chlorides, organic compounds, metals) that might catalyze the explosive decomposition of NH4N03. It is also wise to keep the melt mass low and to vent it to avoid pressure buildup. The solid product should be stored well away from the main plant. 

Another application of tumblers is to the manufacture of mixed fertilizers, in which solid ammonium nitrate, liquid ammonia, liquid phosphoric acid, and liquid sulfuric acid are charged separately and reacted. The incidental agglomeration is excessive, however, and the process must be followed by appropriate crushing and size classification. 

Uses of ammonia. The various uses of ammonia include the use of the compound both as such and in the form of other compounds made from ammonia. In the liquid state, much ammonia is used as the refrigerant liquid in commercial refrigeration plants and in the manufacture of ice. Some liquid ammonia is used both in the laboratory and commercially as a solvent, and its solvent properties are in many respects similar to those of water. Great quantities of ammonia are used in the manufacture of nitric acid, sodium hydrogen carbonate, normal sodium carbonate, aqueous ammonia (or ammonium hydroxide), ammonium salts for use as fertilizers, and many other useful chemicals. 

The chemistry of ammonia and the ammonium ion is vast ammonia is of immense industrial importance and is produced in larger molar quantities than any other chemical. More than 80% of the ammonia produced is used in fertilizers, with additional uses including the synthesis of explosives, the manufacture of synthetic fibers (such as rayon, nylon, and polyurethanes), and the synthesis of a wide variety of organic and inorganic compounds. As described in Chapter 6, liquid ammonia is used extensively as a nonaqueous ionizing solvent. 

Ammonia is also used commercially in the manufacture of fertilizers, mainly ammonium nitrate, urea, and ammonium sulfate. It is used to a smaller extent in the refrigeration industry. Liquid ammonia is an excellent solvent for certain substances, which ionize in the solutions to give ionic reactions similar to those occurring in aqueous solutions. Ammonia is marketed... 

Ammonia is easily liquefied, and the liquid is used as a nitrogen fertilizer. Ammonium salts, such as the sulfate and nitrate, are also sold as fatilizers. Large quantities of ammonia are converted to urea, NH2CONH2, which is used as a fertilizer, as a livestock feed supplement, and in the manufacture of urea—formaldehyde plastics. Ammonia is also the starting compound for the preparation of most other nitrogen compounds. 

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