Fertilizers, fluid nitrogen solutions

These nitrogen solutions are used both for direct field appHcation and as a nitrogen ingredient in fluid mixed fertilizers. 

Micronutrients in Fluid Fertilizers. In terms of homogeneity and even distribution, fluid fertilizers are probably the best micronuttient carriers. Fluid carriers of micronutrients usually are nitrogen solutions, clear Hquid mixtures, or suspensions. Some micronutrients, however, are appHed as simple water solutions or suspensions. FoHar micronuttient sprays often contain only the micronuttient material in water solution. 

The term fluid fertilizers as used in this chapter refers to fertilizers such as anhydrous ammonia, aqua ammonia, nonpressure nitrogen solutions (28% to 32% N), liquid mixed fertilizer, and suspensions. Production of anhydrous ammonia, urea, and ammonium nitrate are presented in other chapters however, the use of these materials to produce fluids and their application will be discussed in this chapter. 

The fluid fertilizer industry started emerging as a significant industry in the United States during the early 1960s. By 1965 fluid consumption amounted to more than 5 million tonnes and represented about 18% of all fertilizers consumed. Table 10.1 gives the yearly consumption of fluids (anhydrous ammonia + aqua ammonia + nitrogen solution -f- solution mixtures + suspensions) during the period 1965-93. 

The United States uses the most fluid fertilizers. Table 10.2 summarizes fluid consumption by type in the United States during the period, 1960-93 [2] These and-other— data indicate that in 1993 about 40% of the total fertilizers applied in the United States were in the fluid form over one-half of the nitrogen was in the fluid form. The data also show that the most popular fluid in the United States is anhydrous ammonia its use remained constant for several years and decreased slightly during 1993. The popularity of anhydrous ammonia for direct application is essentially nil in all other countries except Canada. The next most popular fluid in the United States is a nonpressure nitrogen solution that contains between 28% and 32% nitrogen (N). 

Kingdom, Spain, and some of the CIS states. Most of the phosphate solutions (11-37-0 or 10-34-0) are mixed with nitrogen solutions and potash to produce NPK solutions and suspensions. Usually when nitrogen solutions become acceptable, the use of fluid mixtures soon follows fluids will become more popular as emphasis on efficient use of fertilizer increases. 

The use of fluid phosphate has not had the worldwide popularity of fluid nitrogen fertilizers (mainly UAN solution). However, fluids have captured a significant amount... 

Many companies report that they have fliid fertilizer application equipment for nitrogen solutions, and, in order to use it more effectively, they must convert solids to fluids. 

The most popular nonpressurized nitrogen solutions are prepared from urea and ammonium nitrate and contain between 28 and 32% of nitrogen. No special equipment is needed for their storage and application they are easier to mix and to handle than solids, have low distribution losses, can be accurately placed, are suitable for foliar and aircraft application, and are excellent carriers of micronutrients as well as of pesticides and herbicides. As a result, about 60% of U.S. fertilizer nitrogen is now applied in fluids, and the use of solutions is becoming also more widespread in Europe. ... 

Mention was made earlier of the significant quantity of nitrogen applied to farmlands in the form of urea-ammonium nitrate solution and aqua ammonia. Since the late 1950s, there has also been a growing practice of applying mixed fertilizers (NP and NPK) in fluid form. In fact, the growth of the fluids market paralleled bulk-blended products. In 2002/03 about 25 million mt of fluids was produced and corresponded to 7 percent of the world production. North America, and Europe are major markets for fluids. Fluids are also used in high-value crops in some countries of the Middle East and Latin America. 

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