OP-II-3

KN-2REVERSED-FLOW REACTORS: POTENTIAL AND REALIZEDBunimovich G.A. and Matros Yu.Sh.Matros Technologies, Inc., St. Louis, MO 63017, USA,E-mail: grigorii@matrostech.comThe reversed-flow reactor (RFR) combines chemical processes with regenerativeheat exchange or adsorption in fixed bed units. The system realizes bell-shapedconcave or convex profiles of temperature or concentration of adsorbed compoundsalong the bed length. For gas-phase exothermic processes the heat can beeffectively trapped in the center of the bed at low temperature of inlet and outlet gas.The efficiency of heat recuperation can reach 95%-97%, which is important for suchprocesses as thermal or catalytic oxidation of volatile organic compounds in dilutedair or gases.This paper is suggested for a key-note presentation. We will review the history,current status and challenges in reversed-flow reactor technology. The presentationwill be focused more on commercially realized processes.The original development of a heat-trapping RFR for exothermic reversiblereaction such as oxidation of SO 2 to SO 3 [1-3] was followed by more complex ideasincluding asymmetric reactors combining exothermic and endothermic processes [4-7], adsorptive reactors [8-9] and reactors with retained carried-over catalyst [10]. Wewill discuss the RFR applications tested in pilot scale: automotive converters [11],asymmetric fuel reformers [6-7], and zone reactor for bromine-mediatedfunctialization of methane [9].The following part of the presentation will briefly review the reactor fundamentals.Even a simple one-dimensional model demonstrated rather complex behaviorincluding multiplicity of “periodic” steady states as well as quasi-periodic and chaoticoperations [12-15]. The issues of stability and parametric sensitivity are important forlarge-scale RFRs where the beds can have spatial non-uniformities, and problemswith catalyst overheating and process stabilization and control can arise. Anotherimportant challenge relates to temperature profile optimization for achieving highreactant conversion. The presentation will discuss solutions adopted in someapplications.Commercial reversed-flow reactors were developed for oxidation of SO 2 insulfuric acid production, complete oxidation of volatile organic compounds (VOC),24