Nielsen Ed. , Ammonia Springer-Verlag Berlin Heidelberg

Nielsen (Ed.), Ammonia springer-Verlag Berlin Heidelberg 1995... 

Figure 8.23. The solid and monotonically declining line to the right represents the equilibrium curve. The four curves represent lines with constant rates in the same plot. Since we want to operate at points where of maximum ammonia concentration, the optimal operation line is defined as the line running parallel to the equilibrium curve, passing through all the maxima. [Adapted from I. Dybkjaer, in Ammonia Catalysis and Manufacture (1995) Ed. A. Nielsen. Springer-Verlag, Berlin/Heidelberg, p. 199.]...

Hojlund Nielsen, P.E. In Ammonia, Catalysis and Manufacture A. Nielsen, ed., Berlin Heidelberg, Springer-Verlag, 1995,191. 

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