Leading Concept Ammonia Process

Some of the ammonia process technologies that are available include KAAP/ /m.s , Haldor Topspe, LAC (or Linde Ammonia Concept), LCA (or Leading Concept Ammonia), Ammonia Casale, and Uhde. 

The Leading Concept Ammonia (LCA) process is designed to approach the capital cost and energy advantages of larger capacity (> 1,000 tonne per day) ammonia plants while producing only 400 to 600 tonnes per day of ammonia. This technology was developed by Imperial Chemical Industries (ICI), and the first plant started up in 1988. 

The LCA (Leading Concept Ammonia) is essentially a simplified form of the standard ammonia synthesis process that is more suitable for smaller plants. It is described in References 1, 26, 27, and 29. 

K. Elkins, I. R. Barton, 39th AIChE Ammonia Safety Symp., Vancouver 1994 Ammonia Plant Saf. 35 (1995) 276 Operational Performance of the ICl Leading Concept Ammonia (LCA) Process, ICI Catalco tech, paper 274W/126/3/LCA. 

The reforming exchanger concept totally eliminates the furnace and uses a hot secondary reformer outlet as its heat source. Surplus air over the stoichiometric demand or oxygen-enriched air in the secondary reformer is required to balance the heat demand for the primary reforming reaction. Chiyoda proposed this concept in 1984 [26,271 however, ICI was the first one. to comr mercialize a reformer exchanger called the Gas Heat Reformer (GHR) as part of their Leading Concept Ammonia (LCA) process. The GHR is discussed further under the LCA process section. 

Breakthroughs in small-scale capacity processes are the Kellogg (KRES system) and ICI Leading Concept-Ammonia (LCA) process. The capacity of the referenced installation is 457 tpd, and the total energy consumption is estimated at 7.22 Gcal/tonne of ammonia, h-stallation also produces carbon dioxide that has more than 99% purity. The processes are described in Chapter 6. 

Famell, P.W., Commissioning and Operation of ICI Katalco s Leading Concept Methanol Process, Prepared for presentation at the AIChE Ammonia Safet Symposium - Tucson, Arizona, September 18-20,1995. 

Kitchen, D., et al. 1991. The ICI Leading Concept Ammonia (LCA) Process. In D. R. Waggoner and G. Hoffmeister, eds.. Environmental Impacts of Ammonia and Urea Production Units. Muscle Shoals, Ala. IFDC, pp. 47-54. 

LCM [Leading Concept for Methanol] A process for making methanol, combining the ICI Low Pressure Methanol process with the steam reforming section of the LCA ammonia process. Developed by ICI in 1990 and piloted in Melbourne, Australia, from 1994. Envisaged for floating factories in off-shore gas fields. 

LCA [Leading Concept for Ammonia, formerly Low-Cost Ammonia] A process for making ammonia from air and natural gas. Essentially a simplified form of the standard ammonia synthesis process, more suitable for smaller plants. Thermal economies are achieved in the steam reforming section. Developed by ICI from 1985 to 1988. Two units began operating at the ICI plant in Severnside, UK, in 1988. The first non-ICI installation was designed by KTI for Mississippi Chemicals, Yazoo City, MS. The name appears to be no longer used. 

The use of air alone leads to a relatively low calorific value product gas, of the order of 4-6 MJ/mi (LHV basis), which is not attractive for H2 production in view of the large bulk of N2 to be separated from it compared to a preseparation from the air. Only the application of hydrogen in ammonia production would need N2 as cofeedstock. Therefore, in this context only steam- or oxygen-blown gasification concepts are dealt with. The raw product gas can, thus, be produced by an oxygen-blown or indirectly heated steam-blown processes. 

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