Mont Cenis process

W.F. Scholvien, ChemMetEng 38, 133 (1931) (Low pressure Mont Cenis process for the manufacture of nitric acid) 19) H.A. Curtis,... 

The Mont Cenis process was an early ammonia synthesis process that was similar to the Haber-Bosch process except that it used coke-oven gas1. It was started up by The Royal Dutch Group at Ymuiden, The Netherlands in 192931 32. 

The synthesis pressure has, as mentioned above, an important influence on the performance of the ammonia synthesis loop because of its influence on the reaction equilibrium, reaction kinetics, and gas/liquid equilibrium in the product separation. A wide range of operation pressures has been used in practice, from less than 100 bar (in the early Mont Cenis process and recently in the ICI AMV-process) to 1000 bar (in the early Claude and Casale processes). The trend in modern plants has been to select operating pressure in the low to medium pressure range typical operating parameters for modern synthesis loops at two different pressures are given in Table 6.1. 

Uhde GmbH is one of the pioneers in the ammonia industry. Even before the Second World War they constructed ammonia plants (based on the Mont Cenis process). Later they built plants in cooperation with many other companies, such as OSW, Topsoe, and ICI. 

An estimate of world ammonia capacity for 1932-33, showed that the Haber-Bosch process represented 53 per cent, Casale 16 per cent, Fauser 11 per cent, Claude 8 per cent, Mont Cenis 6 per cent, Nitrogen Engineering Corporation (USA) 5 per cent, and Showa Hiryo (Japan) 1 per cent. Together the various operational plants had the ability to produce three million tons of ammonia nitrogen, though by 1935 only 43 per cent of this figure was actually manufactured. ... 

During the 1930 s and the Second World War the worldwide production capacity was increasing rapidly, and in 1945 about 125 ammonia plants existed with a total capacity of 4.5 million tonnes/year. The most important processes at that time were Haber-Bosch, Casale, Claude, Fauser, NEC and Mont Cenis. 

Old converter types with countercurrent flow in cooling tubes are the Mont Cenis reactor [385, 503], the original Haber-Bosch converter [504], the Claude converter [505], and the old Fauser converter [506, 507]. These early converter types were all used in relatively small plants they are not used in modern processes. 

Mont Cenis-Uhde process of ammonia synthesis. 

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