Ammonia synthesis world production

Ammonia synthesis is one of the most important processes of chemical industry tens of millions of tons of this product are synthesized annually in various countries of the world. On a commercial scale the reaction is operated on promoted iron catalysts at temperatures near to 500°C and high pressures, mostly at 300 atm. At present K20, A1203, and CaO in amounts of several parts by weight per 100 parts of catalyst are usually employed as promoters. The application of high pressure is caused by the reversibility of the reaction molar fraction of ammonia corresponding to the equilibrium... 

Today, solid-catalyzed gas reactions are executed to an extent of several billions of tonnes per annum. To name only a few important examples Steam reforming of methane-rich natural gas to synthesis gas (H2 + CO), conversion of CO with H20 to C02 + H2, conversion of CO with H2 to methane, ammonia synthesis, oxidation of S02 to S03 (sulphuric acid production), oxidation of NH3 to NO (nitric acid production). The world production of ammonia in 1995 amounted to 90 m tonnes and... 

Bosch, Karl. (1874-1940) A German chemist who was the 1931 recipient of the Nobel Prize with Friederick Bergius. In World War I, his catalyst study led to the production of synthetic gasoline. He also worked in the area of chemical high-pressure methods. His research in ammonia synthesis aided in the manufacture of fertilizers and explosives. His doctorate was awarded in Liepzig, Germany. 

Despite the apparently straightforward nature of these procedures to the feedstocks for ammonia synthesis and the free source of nitrogen from the air, this combination of approaches has become feasible only for relatively small ammonia plants of around 100 tonne/day, or for special process situations where abundant hydrogen is available. Today, ammonia plants of capacities of 900 tonne/day are common and a few as large as 1650 tonne/day are now operating worldwide. Thus it can be seen that the process sequence described above is not a major contributor to world ammonia production. 

In early days of Phase I, the predominant feedstock for ammonia synthesis was coke. Synthesis gas was either produced at atmospheric pressure in water-gas shift units or prepared by purification of coke oven gas. In these early plants, the process effluents from the ammonia converter were cooled without recovery of heat. Due to the lack of technology regarding the attainable size of the converter pressure shell, the physical dimensions of the converter were limiting factors for the achievable production capacity. Therefore, a particular emphasis was placed on maximization of the production capacity for a given volume [139]. During World War II, several plants were built in the United States, based on natural gas feedstock. Since then, natural... 

Synthesis of ammonia in the Haber-Bosch process is one of the best studied catalytic processes. The process was developed by Fritz Haber and Carl Bosch and patented in 1910 (Haber, 1910) Haber was awarded the Nobel Prize in chemistry in 1918 for this work. Today, almost all ammonia production is based on the Haber-Bosch process, and it is one of the largest chemical processes in the world with a yearly production of approximately 120 million tonnes (from the International Fertilizer Industry Association, World Ammonia Statistics for 2005). The main use of ammonia is as fertilizer for agriculture, which constitutes 80% of the world production. 

The curves reflect the strong rise after World War II. At the turn of the century the German chemical industry exclusively employed chemists. Only with the rise of the ammonia synthesis did a larger number of engineers take up activities. They increased with the further extension of continuous catalytic techniques to other products whereby the importance of equipment also increased. Nowadays 50% of the personnel with university educations are composed of engineers in 1950 their share amounted to only one third. 

In 1909 the German Chemist Fritz Haber discovered a catalyzed process [13], which allowed the synthesis of ammonia (NH3) from the elements hydrogen and nitrogen. He received the Nobel prize in chemistry for his discovery. The Nobel prize for Fritz Haber was a subject of controversy because Haber is also the inventor of war gas (phosgene COCI2), which killed hundreds of thousands of soldiers in World War I. Conscience-stricken, Haber s wife committed suicide. Carl Bosch succeeded to scale up Haber s synthesis from the laboratory scale to industrial production. After World War I other industrialized countries also introduced ammonia synthesis and therefore the consumption of hydrogen increased rapidly. 

Since the initial development of its synthesis, the industrial production of ammonia has been steadily increasing as can be seen from the curve (Figure 1), and in 2005 the world production has reached 147 million metric tonnes. Today 1.2% of the total world energy consumption is used for production of ammonia. 

By September 1913, BASF was producing 20 metric tons of ammonia a day using the Haber-Bosch process. Eventually, enough ammonia was produced by the chemical industry to free Germany and the world of dependence on Chile saltpeter for fertilizer. Chemists had thwarted the Malthusian threat. Yet, the victory proved bittersweet the new ammonia synthesis also became the basis for the production of nitric acid, used to make many of the explosives employed in the wars that rocked Europe and the rest of the globe in the first half of the twentieth century. 

The annual production of ammonia is about 1.8 x 10 tons (from FAO), while the annual demand of the catalyst is about (18 — 23) x 10 tons in the world. In China, the capacity of ammonia synthesis catalysts is about 7,000 tons, the production is about 5,000-6,000 tons recently. Among these catalysts, about 4,500-5,000 tons are supplied to domestic market and the rest, about 1,000 tons, are exported. 

The most important details in the technology of ammonia synthesis were kept confidential until the factory in Oppau was opened publicly, thus allowing outsiders to visit. The British Nitrogen Products Committee had estimated that the cost of ammonia synthesized from its elements would be about 50% more expensive than that from calcium cyanamide. This is why calcium cyanamide factories were built during, and even after, the First World War. 

Layered vessels were developed in the United States and Germany at about the same time during World War II. In Germany they were used in ammonia plants as well as for producing gasoline from coal. In the United States they were used for ammonia-synthesis processes for the ultimate production of nitrates. Since... 

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