III International Conference

PP-I-82EXPLOSION SAFETY IN GAS TRANSFERRING SYSTEMS WITH THE USE OFLAYER OF CATALYSTTyulpinov D., Suworin A., Tyulpinov A.Institute of Technology, Severodonetsk, UkraineE-mail: sti @ sti.lg.uaAfter the flame has been extinguished due to gas flow phlegmatization by the products ofcatalytical oxidation the lowering of bed temperature down to initial temperature beforeignition is provided within the specified range of gas flow rate. Layer-by-layer cooling offixed catalyst bed occurs using cold make-up mixture of combustible gas. Thus the method ofexplosion protection for gas transferring systems provides for independent, external controlfreeeffective flame localization and extinguishing without interruption of combustible gasflow.Flame arresters used in industry at present localize burning without extinguishing it. Tostop burning the flow of combustible mixture has to be cut off. A new approach is proposed toextinguish flame without interrupting the flow based on use of catalytically active material asa flame arrester package. Investigations in this area found out the presence of a hightemperaturezone of catalytical oxidation of combustible components. The influence of gasflow rate through the bed on position stability of the high-temperature zone and its locity inlongitudal direction has been studied. The data obtained were used to develop a novel methodof explosion protection in operation of gas transferring systems.Flame arrester design is radically simplified when maintain the corresponding gas flowrates which provide cooling of catalyst bed after the combustion mixture has extinguished theflame. It allows to eliminate measures maintaining temperature regime of catalyst supplyingheat carrier to heat exchanger and therefore to exclude the heat exchanger from reactordesign. Preliminary determinations of heat propagation velocity of catalytical oxidation zoneare required for this method as well as starting velocity of catalyst fluidization.Gas flow rate in flame arresting element under normal conditions and free cross-section islimited by W p < W п < W в range for non-contracted fixed catalyst bed and W р < W п forcontracted fixed catalyst bed, where W р - heat propagation velocity of catalytical oxidationzone; W п - gas flow rate in flame arresting element under normal conditions and free crosssection;W в - starting velocity of catalyst fluidization.The upper limit of gas flow rate for contracted fixed catalyst bed is not defined, that ismaximal velocity is not limited.154