Advantages and Disadvantages of a CSTR

Some advantages and disadvantages of a CSTR can be realized at this stage from the model outlined above, in anticipation of the quantitative development to follow  

The most obvious disadvantage in principle stems from the fact that the outlet stream is the same as the contents of the vessel. This implies that all reaction takes place at the lowest concentration (of reactant A, say, cA) between inlet and outlet. For normal kinetics, in which rate of reaction (-rA) decreases as cA decreases, this means that a greater volume of reactor is needed to obtain a desired conversion. (For abnormal kinetics, the opposite would be true, but this is unusual-what is an example of one such situation ) 

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