Ammonia production future developments

The mature Haber-Bosch technology is unlikely to change substantiaHy in the foreseeable future. The centers for commercial ammonia production may, however, relocate to sites where large quantities of natural gas are flared from cmde oil production, eg, Saudi Arabia or Venezuela. Relocation would not offset the problems for agriculture of high transportation and storage costs for ammonia production and distribution. Whereas the development of improved lower temperature and pressure catalysts is feasible, none is on the horizon as of this writing. 

The absorption technique using hot potassium carbonate has also been developed to capture C02 (Probstein and Hicks, 1990). The chilled ammonia process is another solvent-based C02 capture technology where ammonia carbonate slurries are used to capture 90% of the C02 in the gas stream mixture gas forming ammonia bicarbonate in the process. A pilot-scale chilled ammonia unit for 5 MW equivalent flue gas capture is under construction by ALSTOM and EPRI. Although this process is developed for a combustion system, the results will provide valuable information for the future development of such a process for hydrogen production. According to ALSTOM, commercial products on chilled ammonia process will be available by 2010 (Alstom, 2007). 

In the future, developing nations are expected to continue to account for most of the increases in ammonia and urea capacity. Ammonia capacity is expected to increase by about 20 million tonnes and urea capacity by about 12 million tonnes of nitrogen between 1996 and 2002. The availability of relatively low-cost feedstock (usually natural gas) will be a major determinant as to where this new capacity is installed. Ammonium nitrate and ammonium phosphate capacity are also expected to rise35. The following tables summarize anticipated world capacity for nitrogen products by year (Table 3.1) and by major regions or countries (Table 3.2)148. 

It is difficult to venture a prognosis for the future development of ammonia production technology. As about 85% of the ammonia consumption goes into the manufacture of fertilizers, it is obvious that the future of the ammonia industry is very closely bound up with future fertilizer needs and the pattern of the world supply. 

Although the first report was published in 1888 by Mond and Longer [2], the technical importance of the WGSR was not recognized until the development of the Haber process. Currently, the WGSR is used in various chemical processes, such as hydrogen and ammonia production, Fisher-Tropsch and methanol synthesis. Also, it is considered to be an important process for the removal of CO in small-scale future power generation, based on fuel cells for both mobile and stationary applications. 

Based on these developments, the foreseeable future sources of ammonia synthesis gas are expected to be mainly from steam reforming of natural gas, supplemented by associated gas from oil production, and hydrogen rich off-gases (especially from methanol plants). 

The improvements made in hydroaminomethylation technology suggest that certain variants of this reaction are sufficiently developed for the potential production of amines. The synthesis of linear tertiary and secondary amines from terminal alkenes shows promise in this regard. Belief s recent contributions towards hydroaminomethylation using ammonia to produce linear primary amines, which are of industrial significance due to their abundance, suggest a bright future for this reaction. Branched selective hydroaminomethylation remains relatively underdeveloped and needs further study. 

Researchers returned to the oxidation of ammonia in air, (recorded as early as 1798) in an effort to improve production economics. In 1901 Wilhelm Ostwald had first achieved the catalytic oxidation of ammonia over a platinum catalyst. The gaseous nitrogen oxides produced could be easily cooled and dissolved in water to produce a solution of nitric acid. This achievement began the search for an economic process route. By 1908 the first commercial facility for production of nitric acid, using this new catalytic oxidation process, was commissioned near Bochum in Germany. The Haber-Bosch ammonia synthesis process came into operation in 1913, leading to the continued development and assured future of the ammonia oxidation process for the production of nitric acid. 

In process industry hydrogen is a very important feedstock for a large number of processes like the production of ammonia (fertiliser), various hydrogenation reactions and electricity production in gasturbines. In future hydrogen will play an even more important role because of the rise of the hydrogen based society . This becomes already visible in the fuel cell car recently taken in development. 

In recent years the worldwide production capacity for synthetic ammonia has increased slowly to its current high level from 102 10 t in 1983 to 112 10 t in 1993. Growth has mainly occurred in developing countries, the capacity in the Western World having largely stagnated or in the case of Western Europe decreased. The proportion of worldwide capacity in Western Europe has fallen from 15% in 1983 to 12% in 1993. Some increase in worldwide capacity is expected in the near future. 

The general use of metal ammine complexes can be further kick-started by the utilization of on-board ammonia storage and delivery systems for NO c aftertreatment on diesel or lean-bum vehicles. The implementation will create experience with vehicle integration, safety and distribution. In addition, bulk production of compact ammine cartridges for DeNO (AdAmmineT ) will drive down the production cost for emerging niche applications, while broad entry into mass markets slowly develops in the future. 

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