Consecutive reactions piston flow

The results in Table 6.3 show that isothermal piston flow is not always the best environment for consecutive reactions. The adiabatic temperature profile gives better results, and there is no reason to suppose that it is the best... 

The results in Table 6.5 show that isothermal piston flow is not always the best environment for consecutive reactions. The adiabatic reactor gives marginally better results, and its capital cost will probably be lower. However, both reactors as modeled here assume preheated feed. The adiabatic reactor would require a feed preheater. A shell-and-tube reactor might be used for both the preheating and the reaction, although the reactor would no longer be isothermal. This is a point for detailed design calculations. 

---