Potassium fertilizers consumption

The worldwide production capacity for potassium nitrate in 1996 was ca. 1.3- 10 t, of which 75% was for fertilizers and 25% for industrial applications. Table 2.2-10 gives the potassium nitrate consumption by region for 1997. 

World consumption of potassium salts presentiy exceeds 28 million t of K O equivalent per year. About 93% of that is for fertilizer use (see POTASSIUM compounds). The potash [17353-70-7] industry is essentially a mining and beneftciation industry. The two main fertilizer materials, KCl and K SO are produced by beneftciating ores at the mine sites. The upgraded salts then are shipped to distributors and manufacturers of mixed goods. 

The most popular fertilizers contain the three major nutrients nitrogen, phosphorus, and potassium, and they are therefore referred to as NPK fertilizers. To illustrate their importance in any economy, in 2000, the world consumption of the total fertilizer nutrient (N + P205 + K20) was 140... 

Table 2.2-9 gives the production and consumption statistics for potassium-containing fertilizers by region for 1994 ... 

Table 2.2-9. Production and Consumption of Potassium-Containing Fertilizers by Region in 1994 in 10 t as K2O.

Economic Importance. The worldwide production of magnesium sulfate products including potassium magnesium sulfate (fertilizer) was 3.4 10 t/a in the mid-1970 s of which 2.3 10 t was kieserite MgS04 H2O (a byproduct of the potash industry). The main producer countries are the USA and the Federal Republic of Germany. The USA consumption in 1996 excluding natural kieserite was 57-10 t. 

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. 

Use of potassium in fertilizers. The current world consumption of KjO is approximately 20 Tg y" (Table 9.5). The amount of K applied per sq. metre of arable land varies widely among different countries of the world. In 1966, for example, Italy averaged about 1 gK m , while Belgium applied 16 gK m . The Netherlands and West Germany also apply high rates of K, while France, Denmark, the United Kingdom, and the U.S.A. average 6 gm" or lower. However, the U.S.A. uses about 25% of the world s present consumption (Barber et al., 1968). 

There are a considerable number of stable crystalline salts of the ammonium ion [14798-03-9] NH. Several are of commercial importance because of large scale consumption in fertilizer and industrial markets. The ammonium ion is about the same size as the potassium and mbidium ions, so these salts are often isomorphous and have similar solubiHty in water. Compounds in which the ammonium ion is combined with a laige, uninegative anion are usually the most stable. Ammonium salts containing a small, highly charged anion generally dissociate easily into ammonia (qv) and the free acid (1). At about 300°C most simple ammonium salts volatilize with dissociation, for example... 

Italian agriculture is among the largest users of fertilizers and pesticides in the OECD. Total consumption of mineral fertilizers has reached a peak in 1992 in the following years the total quantities of sold fertilizers have somewhat decreased, even if the annual mean quantity was substantially stable in 1991-1994, estimated in about 65 kg/ha of nitrogen, 461 /ha of phosphorus and 27 1 /ha of potassium. 

To understand the role of fertilizers, it might be helpful to think about soybean. Soybean is the world s most important source of protein and accounts for nearly 70% of the protein meal consumption and nearly 30% of vegetable oil consumption [16]. Nitrogen, phosphorus, and potassium (in that order)... 

Phosphorus, in addition to nitrogen and potassium, is an essential ingredient of modern high analysis fertilizers. An ever-increasing global demand for food has resulted in increased fertilizer use and increased phosphate rock consumption. The data presented in Table 10.2 show a marked increase in world phosphate production, equivalent to an annual growth rate of 3.5 percent from 1970 to 1989. 

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