A rigorous heterogeneous model for adiabatic ammonia reactors is used to ex
plore the application of internal heat exchange theory to cross the adiabat
ic reaction equilibrium values and to improve the conversion in ammonia rea
ctors. The mathematical model is developed for adiabatic ammonia converters
and the resulting two-point boundary value differential equation for the c
atalyst particles is solved using the orthogonal collocation method. Two si
mple configurations of reactors with heat interchangers are implemented. An
industrial ammonia reactor having three adiabatic beds with Montecatini Ed
ison catalyst and interstage cooling is used as the basis for comparison. T
he comparison shows that an increase of 13.37% of the overall ammonia conve
rsion is possible. The results presented in this study reveal the potential
application of energy optimization and integration in the ammonia industry
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