STUDIES OF ADIABATIC FIXED-BED REACTORS. (I). IGNITION OF REACTORS.

An approach for determining ignition temperature of adiabatic fixed-bed reactors is suggested. A phase plane of dimensionless temperature and of dimensionless concentration is used to show both the ignition curve and the extinction curve of a single catalyst pellet. Also expressed in the phase plane is the trajectory depicting the deepening of the reaction, the trajectory being the operating line of the reactor. This trajectory is a straight line, the slope of which is always minus 45 degree . The reactor definitely ignites once the trajectory touches the catalyst ignition curve. A kinetics-free approach is recommended which enables precise determination of critical inlet temperature causing reactor ignition. Zero-order assumption can be securely made because only very limited error is brought about. In the meantime, experimentation is greatly simplified.