A kinetic-free approach to the sensitivity analysis of axial flow continuous reactors: A general experimental method

The intensification of fast and exothermic reaction processes is an important development trend of the chemical industry, because of productivity, safety and product quality reasons. Whenever the reaction can be performed in tubular rather than in stirred tank reactors, a number of additional advantages can be achieved, in terms of a higher conversion as well as of an improved heat transfer efficiency per unit volume. In these cases, however, the reactor must be designed and operated so as to prevent its pseudo-adiabatic behavior, which makes the system sensitive to even normal fluctuations of the process variables as well as to the design parameters, with unpredictable effects on the process performances. In this work a general experimental procedure is presented, through which the sensitive behavior of a tubular reactor can be detected through local temperature and flowrate measurements, even in the absence of a detailed kinetic characterization of the system. The developed approach has a higher responsiveness compared with the existing criteria and can be easily adopted for finetuning the operating conditions of a running reactor as well as for the design of a new one. The proposed method has been validated through experimental data, both in the non-sensitive and sensitive regimes, of a well-known catalytic process of the chemical industry.