Sulfur consumption

Sulfur consumption reached peak levels by the beginning of the 1990s. The apparent annual consumption of sulfur in all forms in the United States nearly reached 13.2 million metric tons by 1995. World sulfur production increased steadily from 53.6 million metric tons in 1984 to an all-time high of 60.1 million metric tons in 1989, declining to 54.6 million metric tons in 1995. 

Agriculture is the largest industry for sulfur consumption. Historically, the production of phosphate fertilizers has driven the sulfur market. Phosphate fertilizers account for approximately 60% of the sulfur consumed globally. Thus, although sulfur is an important plant nutrient in itself, its greatest use in the fertilizer industry is as sulfuric acid, which is needed to break down the chemical and physical stmcture of phosphate rock to make the phosphate content more available to plant life. Other mineral acids, as well as high temperatures, also have the abiUty to achieve this result. Because of market price and availabiUty, sulfuric acid is the most economic method. About 90% of sulfur used in the fertilizer industry is for the production of phosphate fertilizers. Based on this technology, the phosphate fertilizer industry is expected to continue to depend on sulfur and sulfuric acid as a raw material. 

Paints. Paints account for perhaps 3% of sulfur consumption (see Paint). The main sulfur use is for the production of titanium dioxide pigment by the sulfate process. Sulfuric acid reacts with ilmenite or titanium slag and the sulfur remains as a ferrous sulfate waste product. Difficulties with this process have led to the development of the chloride process (see Pigments, inorganic Titanium compounds). 

Nonferrous Metal Production. Nonferrous metal production, which includes the leaching of copper and uranium ores with sulfuric acid, accounts for about 6% of U.S. sulfur consumption and probably about the same in other developed countries. In the case of copper, sulfuric acid is used for the extraction of the metal from deposits, mine dumps, and wastes, in which the copper contents are too low to justify concentration by conventional flotation techniques or the recovery of copper from ores containing copper carbonate and siUcate minerals that caimot be readily treated by flotation (qv) processes. The sulfuric acid required for copper leaching is usually the by-product acid produced by copper smelters (see Metallurgy, extractive Minerals RECOVERY AND PROCESSING). 

Other Uses. Other uses include intermediate chemical products. Overall, these uses account for 15—20% of sulfur consumption, largely in the form of sulfuric acid but also some elemental sulfur that is used directly, as in mbber vulcanization. Sulfur is also converted to sulfur trioxide and thiosulfate for use in improving the efficiency of electrostatic precipitators and limestone/lime wet flue-gas desulfurization systems at power stations (68). These miscellaneous uses, especially those involving sulfuric acid, are intimately associated with practically all elements of the industrial and chemical complexes worldwide. 

Sulfur (qv) is among the most widely used chemicals and often considered to be one of the four basic raw materials of the chemical iadustry. In 1993, worldwide production of sulfur reached 55 million metric tons (1). Production of sulfuric acid consumes the vast majority (- 90%) of sulfur (2) (see Sulfuric acid and sulfur trioxide). This acid is a steppiag stone ia the production of other sulfur-containing compounds, most notably ammonium sulfate fertilizer which accounts for 60% of the total worldwide sulfur consumption (2) (see Ammonium compounds Fertilizers). 

Demand for sulfur in Mexico is even more oriented toward the fertilizer sector than it is in the U.S. and Canada. In 1978, fertilizer uses accounted for about 75 percent of the total. We expect that the future use of sulfur in Mexico will continue to be oriented heavily toward the fertilizer industry. By 1990, Mexican sulfur consumption should be almost three times the current level. 

More than 90% of world sulfur consumption is used in the production of sulfuric acid, much of which goes to the fertilizer industry. Smaller amounts of sulfur are used in the manufacture of gunpowder, matches, phosphate, insecticides, fungicides, medicines, wood, and paper products, and in vulcanizing rubber. Despite slight uncertainties in sulfur demand in the 1990s, its use is still predicted to grow. 

The mean daily sulfur intake varied between 476 mg in women and 619 mg in men. The significantly different S intake is caused by the different high DM intakes, as men consumed on average 17% more food DM than women. The highest daily sulfur consumption of 1492 mg in men was more than two-fold the maximum intake in women (666 mg) (Holland 1996). However, amounts of sulfur taken in by a population of a former sulfur-polluted area were less than the weekly intake of 7.0-... 

No ion exchange resin expense Less steam for evaporation Caustic by-product No effluent lime treatment Reduced sulfuric consumption Lower solids treatment burden... 

Sulfur consumption— about 330-332 kgdVIT of acid produced. 

Sulfur consumption by region in 1992-94 is shown in Table 5.24. For the short to medium term, sulfur is expected to remain in surplus due to increased byproduct sulfur production. Increasing demand for natural gas and the increased need for pollution control will lead to increasing production of recovered sulfur. Elemental sulfur from evaporites and volcanic rocks will be available for many years. The fertilizer industry should be able to obtain the sulfur it needs over the next decade, but the lowest cost reserves presently being used have a limited life expectancy. 

Sulfur consumption Electric power Byproduct steam (at 40 atm) Process and cooling water... 

Only about 1.2% of sulfur consumption is used in rubber vulcanization. Sulfur is also used in many nonrubber applications, ft is used in agriculture to make fungicides and fertilizers. It is also used to make fumigants for dried fruit and wood pulping. Also, sulfur is basically essential to life itself. In addition, about 90% of the sulfur used today is in the production of sulfuric acid, the largest volume industrial chemical in today s commerce. 

The availability of design information on the SFGD process is excellent However, little commercial experience is available to date. The principal drawback of the process is its high requirement for reducing gas, particularly if the end product is elemental sulfur. Consumption figures reportedly show 6.2 moles of H2 per mole of SO2 removed (Radian, 1977). 

More than 90 percent of the elemental sulfur consumed in the United States is converted to sulfuric acid. Table 14.2 shows the pattern of U.S. sulfur consumption during the 1980s. ... 

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