Ammonia fertilizer applications

Tribasic calcium phosphate is obtained from naturally occurring minerals for fertilizer applications. The compound may be prepared in the laboratory by the reaction of sodium phosphate with calcium chloride with excess of ammonia. Also, it can be prepared by treatment of calcium hydroxide with phosphoric acid ... 

The largest sources of atmospheric NH3 are from fertilizer application and livestock washes. Studies of long-term trends imply a 50% increase in ammonia emission in Europe during 30 years between 1950 and 1980. A substantial amount of N is lost as volatile NH3 from plants after fertilizer application and during the senescence... 

Ammonia may be released to soils by natural or S5mthetic fertilizer application animal (including livestock) excrement degradation decay of organic material from dead plants and animals and the natural fixation of atmospheric nitrogen. 

The most probable routes by which the general population is exposed are by the inhalation of ammonia that has volatilized from common household cleaning products and through dermal contact during the use of these products. Inhalation exposure to ammonia by some members of the rural population may occur for those who are near agricultural areas during the fertilizer application period, those near animal feedlots or confinement areas, and those who apply anhydrous ammonia to fields. 

Farmers can be exposed to ammonia when applying fertilizer. The ammonia concentration over a field during the application of gaseous anhydrous ammonia fertilizer was as high as 213 pg/m (300 ppb) (Denmead et al. 1982). Workers at cattle production facilities and those who work under conditions... 

Denmead OT, Freney JR, Simpson JR. 1982. Atmospheric dispersion of ammonia during application of anhydrous ammonia fertilizer. J Environ Qual 11 568-572. 

A nitrification inhibitor that is fully effective would be expected to (1) increase efficiency in the use of nitrogen fertilizers, especially on coarse-textured soils where rainfall is high, or extensive irrigation is practiced (2) make more feasible the practice of fall applications of ammonia (3) make less critical the time of nitrogen fertilizer applications and the need for split applications and (4) reduce nitrogen losses that may occur via nitrite decomposition or reaction with organic matter. Whether the benefits to be expected are sufficient to more than offset the costs of the chemical, and the additional steps involved in its use, is a practical matter that must be determined by the user for his particular soil and cropping system. 

Fig. 2.26 The biogeochemical nitrogen cycle. A ammonia synthesis (man-made N fixation), B oxidation of ammonia (indnstrial prodnction of nitric acid), C fertilizer application, D formation of NO due to high-temperature processes, E Oxidation of N2O within the stratosphere, F oxidation of NO within the troposphere, G ammonia deposition and transformation into ammonium, H biogenic emission, I biogenic N fixation, K denitrification, L nitrification, M assimilation (biogenic formation of amino adds), N mineralization. RNH2 organic bonded N (e. g. amines).

P. Rudolph, The Eurgi Pressure Gasification and Its Application for Ammonia Manufacture, Fertilizer Association of India, New Delhi, India, 1973. 

Ammonia is one of the most important inorganic chemicals, exceeded only by sulfuric acid and lime. This colorless gas has an irritating odor, and is very soluble in water, forming a weakly basic solution. Ammonia could be easily liquefied under pressure (liquid ammonia), and it is an important refrigerant. Anhydrous ammonia is a fertilizer by direct application to the soil. Ammonia is obtained by the reaction of hydrogen and atmospheric nitrogen, the synthesis gas for ammonia. The 1994 U.S. ammonia production was approximately 40 billion pounds (sixth highest volume chemical). 

Uses. Since 1947, 70 to 85% of the annual USA production of nitric acid has gone into the production of NH4 nitrate fertilizer, initially in the form of solid prills currently, increasing amounts have been supplied mixed with excess ammonia and/or urea as aqueous nitrogen solution for direct application to the soil. Some 15% is used in explsj (nitrates nitro compds), and about 10% is consumed by the chemical industry. As the red fuming acid or as nitrogen tetroxide, nitric acid is used extensively as the oxidizer in proplnts for rocketry. It is estimated that current USA capacity for nitric acid is in excess of 10 million tons (Refs 30, 34, 36 37)... 

Ammonia synthesis is the second largest chemical process, after the production of sulfuric acid (see also Chapter 1). It accounts for about 1 % of the total human-related energy consumption. Roughly 80 % of the ammonia produced is used for fertilizers (either as liquid ammonia or as more easily handled salts such as ammonium nitrate, ammonium phosphate, etc.) and, as such, ammonia synthesis is indispensable for our society. Other applications of ammonia are nitrogen-containing... 

Toxic substances such as chlorine and ammonia are a homeland security concern in part because of their widespread use in industrial applications and, hence, their accessibility. When released into the air or water in high concentrations, they can be very poisonous. The major use of ammonia and its compounds is as fertilizers. 

Ammonia may be produced and lost between deposition and collection of excreta in winter housing, during its storage and following land application. The treatment of excreta from winter-housed stock as a waste disposal problem rather than a fertilizer resource results in substantial loss of N as NH3. 

Table 21.2 lists all important direct application materials and their percentage of direct application fertilizers. Direct application use is increasing mainly because of anhydrous ammonia gas becoming popular. It can be pumped in 3-6 in. beneath the soil during plowing and is absorbed by the soil rapidly. Nitrogen solutions can also be applied in this manner (mixture of free ammonia, ammonium nitrate, urea, and water). 

These admirable propositions furnish the key to the application of manures, The continued fertility of a soil for all kinds of crops, depends on the constant return to it of a I the mineral constituents removed by the different crops, If a great increase in one crop hae been effected by the application of one manure alone—for example, of phosphate of bine, or of ammonia —this only proves that all the other ingredients necessary to that crop have been present in sufficient abundance in the soil. The agriculturist would not be warranted by the success of this one experiment in repeating it too often, or the infallible result would be the ultimate exhaustion of his land, No single mineral substance, in however large quantities, can confer permanent fer-tility. This result can only be attained by the combination of all those mineral salts found in the aBhes cf plants, or by the use of a compost, such as carefully prepared farmyard manure, which contains in itself these different ingredients. 

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