SAFE DESIGN OF COOLED TUBULAR REACTORS FOR EXOTHERMIC, MULTIPLE REACTIONS; PARALLEL REACTIONS-I DEVELOPMENT OF CRITERIA

Abstract-Previously reported design criteria for cooled tubular reactors are based on the prevention of reactor temperature runaway and were developed for single reactions only. In this paper it is argued that such criteria should be based on the reactor selectivity, from which eventually a maximum allowable temperature can be derived. To this end and for the pseudo-homogeneous, one dimensional model of acooled tubular reactor in which two parallel, irreversible first order exothermic reactions are carried out, two criteria are develooed for the safe desien and oneration of the reactor. The criteria enable us tochoose tube diameters and operating conditions, which are sare in view of the derived selectivity and of possible runaway as well. The method outlined can be used in the initial design stage and requires kinetic information on both the desired and the undesired reaction