Published March 1990
Imperial Chemical Industries (ICI), U.K. has developed and commercialized a natural gas based ammonia process that is aimed at approaching the capital cost and energy advantages of larger capacities (>1,000 t/day) in plants of smaller sizes (400-600 t/day). Titled the "Leading Concept Ammonia" (LCA) process, the main new design features include milder primary reformer conditions, a gas heated reformer (whereby the secondary reformer product meets the sensible heat and endotherm energy requirements of the primary reformer), a single-stage CO shift reactor, and a pressure swing adsorption step to replace a conventional CO2 removal step.
We describe and compare the economics of the LCA process with the previous most energy efficient ICI process, called the AMV process (evaluated in our PEP Review 83-2-l in February 1984). Our data indicate an advantage in favor of the LCA process throughout the capacity range examined, but with the magnitude of the advantage diminishing at the larger capacities.