APPLICATION CHEMICAL INDUSTRY Fertilizers

Because of the great importance of phosphorus and its compounds in the chemical industry, several books and reviews on their preparation and uses are available.Some of these applications reflect the fact that P is a vital element for the growth and development of all plants and animals and is therefore an important constituent in many fertilizers. Phosphorus compounds are involved in energy transfer... 

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)... 

The phosphate manufacturing and phosphate fertilizer industry includes the production of elemental phosphorus, various phosphorus-derived chemicals, phosphate fertilizer chemicals, and other nonfertilizer phosphate chemicals [1-30], Chemicals that are derived from phosphorus include phosphoric acid (dry process), phosphorus pentoxide, phosphorus penta-sulfide, phosphoms trichloride, phosphorus oxychloride, sodium tripolyphosphate, and calcium phosphates [8]. The nonfertilizer phosphate production part of the industry includes defluori-nated phosphate rock, defluorinated phosphoric acid, and sodium phosphate salts. The phosphate fertilizer segment of the industry produces the primary phosphorus nutrient source for the agricultural industry and for other applications of chemical fertilization. Many of these fertilizer products are toxic to aquatic life at certain levels of concentration, and many are also hazardous to human life and health when contact is made in a concentrated form. 

SOLVENT extraction (liquid-liquid extraction) is the separation and/or concentration of the components of a solution by distribution between two immiscible liquid phases. A particularly valuable feature is its power to separate mixtures into components according to their chemical type. Solvent extraction is widely used in the chemical industry. Its applications range from hydrometallurgy, e.g., reprocessing of spent nuclear fuel, to fertilizer manufacture and from petrochemicals to pharmaceutical products. Important factors in industrial extraction are the selection of an appropriate solvent and the design of equipment most suited to the process requirements. 

For more than one reason clay minerals offer a challenge to colloid scientists. From a practical point of view, the wide occurrence In soils and the relevance for agriculture, fertilization and topsoil mechanical properties may be mentioned. Technical applications are encountered in the paper Industry, in ceramics, in brick production, chemical industry and for cleaning purposes ("fuller s earth"). Invariably, these applications Involve clay minerals as the adsorbents for polymers, monomers and/or ions. Double layers around clay particles enter the picture In connection with these adsorption phenomena and... 

Sulfuric acid being a key product in the chemical industry has many applications. Worldwide 65% is utilized in the manufacture of phosphorus and nitrogen fertilizers, whereas in Western Europe only 31% is so utilized. In the Federal Republic of Germany ca. 90% of the sulfuric acid produced is utilized in the chemical industry. 

Applications Magnesium sulfate is utilized in the potassium chemicals industry for the manufacture of potassium sulfate (from potassium chloride), sodium sulfate and potash magnesia (potassium magnesium sulfate). Magnesium sulfate, particularly as kieserite, is used as a fertilizer (ca. 80% of total consumption). It is also used in the textile industry, in the manufacture of building and refractory materials, in the pulp industry and in the production of animal feedstuffs and motor oil additives. 

The natural biogeochemical peculiarities (see Chapter 4, Section 4 and Chapter 6, Section 4), which favor the development of endemic diseases were complicated by anthropogenic activity. In the area of the Volga-Ural watershed and the Ustyurt plateau, this activity is connected with oil explorations and oil-chemical industry. The watershed of Amu-Daria and Syr-Daria rivers is the agricultural area with intensive irrigated cotton production with application of heavy rates of pesticides and fertilizers. 

Tab. 6.3-1 lists, in alphabetical order, chemicals that are cited in the sales literature of different vendors of equipment for size enlargement by agglomeration. They were compiled by the author, not to paint a concise picture of the use of the technology in the chemical industry but to suggest the great variety of potential applications. Several of the chemicals are synthesized materials that are also found in nature and may also be mentioned in connection with agrochemical (including fertilizer), feed, food, pharmaceutical, and special applications. 

An estimated 7 million metric tons (6.5 million short tons) of potassium carbonate were produced in the United States in 2005. Of that amount, nearly 90 percent was used for the production of fertilizers. Potash provides plants with the potassium they need to stay healthy and grow. Potassium is one of the three major nutrients required by plants, the other two being nitrogen and phosphorus. The next largest application for potassium carbonate is in the chemical industry, where it is used as a raw material to make other chemical compounds, potassium silicate being the most common. 

About 4%-5% of potash production is used in industrial applications. The industrial potash (chemical grade) has a different purity from fertilizer-grade potash. The composition of chemical-grade potash is given in Table 15.13 [51. 

Petroleum extraction and processing is the human exploitation of fossil fuels consisting of hydrocarbons in the form of crude oil and natural gas. The primary use of processed petroleum products is as powerful fuels, particularly for transportation in the form of gasoline, diesel fuel, or jet fuel, and for heating purposes, which account for 84 percent of petroleum use. The remainder of processed petroleum products is used in the petrochemical industry as fuel additives and to create applications such as plastics, specialty chemicals, solvents, fertilizer, pesticides, and pharmaceuticals. Worldwide, about 37 billion barrels of crude oil and natural gas are extracted each year. 

The slurry is fed from above by a variety of feed-in systems onto a filter surface which is arranged horizontally. On here is where the whole filter cycle takes place, and where a number of process and technical engineering problems are more beneficially solved than is the case with the drum filter. This led, particularly after WWII, to a rapid expansion of use of the belt filter [17]. Typical applications today include the chemical industry (zeofite, various salts, the potash industry, aluminium hydroxide, fertilizers, etc.), minerals processing (ore sludge, minerals, coal, etc.) or protection of the environment (flue-gas gypsum, power-station fly-ash, ground remediation, etc.). 

Yu ZX, et al. Application Techniques of Fertilizer Catalyst, Chemical Industry Press, Beijing, 1988, 377. 

Sulfuric acid has such a variety of applications it is difficult to gain a good appreciation of its pervasive role in the chemical industry. More than half of it is used to produce superphosphate and other fertilizers (see pp. 484—485). Other major uses include the manufacture of hydrochloric acid from salt, represented in Equations (17.27) and (17.28),... 

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