POTENTIAL DAMAGE TO FILTRATION SYSTEMS DUE TO VOLCANIC ASH FALLOUT

Natural disasters are able to cause significant damage to industrial structures and infrastructure, such as power plants, water treatment plants, fuel storage facilities, etc. Failures in these systems could worsen the effects of natural disasters on people and economy. For this reason, several studies have been recently oriented at understanding the interaction between natural and industrial risks (NaTech). This work is focused on the study of the potential damage to industrial structures caused by the fallout of volcanic ash. More specifically, the paper describes the preliminary results of a Italian government-funded research project aimed at defining the potentially critical scenarios on industrial installations and infrastructure due to eruptions of Mt. Etna in Sicily (Italy). In the first part, the analysis of existing correlations among the violence of explosion, the concentration of ash in the atmosphere, the duration of eruption and weather conditions will be given. The second part will concern the study of the malfunction of filtration systems and of water treatment systems. The damage to filtration systems is essentially associated with the clogged surface due to the ash deposit. This depends not only on the characteristics of the filter (material, diameter and structure of the fibers, density, etc.), but also on the characteristics of the powders (size distribution) and concentration in the air. In order to generalize the result an adimensional analysis of filter vulnerability based on the Ergun equation for pressure losses has been applied.