Schepp P., Faißt U., 2025, Impact of Explosion Isolation Measures on the Reduced Explosion Overpressure in Vented Vessels, Chemical Engineering Transactions, 116, 655-660.
Explosion isolation systems are protective systems designed to prevent an explosion pressure wave and a flame or only a flame from propagating via connecting pipes or ducts into other parts of apparatus or plant areas (EN 15089:2009, EN16447:2014). During tests as part of the EU type examination of such systems, it was noticed for the first time that increased reduced explosion overpressures can occur in connected explosion-vented vessels due to a retroactive effect on the explosion process. The current dimensioning rules for explosion venting according to the harmonised European standard EN 14491:2012 does not consider such effects, which may result in a dangerous inappropriate design of explosion vented vessels in particular cases. Especially large process vessels of limited mechanical strength like e.g. filter houses which are as a rule protected by explosion venting, can be at risk. A research project was launched in order to better understand the observed phenomena and with the aim of identifying the influencing parameters so that these effects can be taken into account in the design of the system. The results of these investigations made it possible to formulate a hypothesis which explains the observed phenomena and which served as the basis for the development of numerical value equations which can be used to estimate the increase in the reduced explosion overpressures due to the influence of the isolation device.
