Critical Bursts in Filtration

Abstract

Particle detachment bursts during the flow of suspensions through porous media are a phenomenon that can severely affect the efficiency of deep bed filters. Despite the relevance in several industrial fields, little is known about the statistical properties and the temporal organization of these events. We present experiments of suspensions of deionized water carrying quartz particles pushed with a peristaltic pump through a filter of glass beads measuring simultaneously the pressure drop, flux, and suspension solid fraction. We find that the burst size distribution scales consistently with a power law, suggesting that we are in the presence of a novel experimental realization of a self-organized critical system. Temporal correlations are present in the time series, like in other phenomena such as earthquakes or neuronal activity bursts, and also an analog to Omori's law can be shown. The understanding of burst statistics could provide novel insights in different fields, e.g., in the filter and petroleum industries.

Clogging at pore scale and pressure-induced erosion

“…Experiments (see Ref. [3]) have shown that the particle concentration is a crucial factor for the clogging and erosive behavior in deep bed filtration. Therefore we run a set of simulations where only C in is varied.…”

“…Erosion in porous media plays an important role in a variety of systems, for example sand production in oil reservoirs [1,2] or breakthrough in water treatment plants. Bianchi et al [3,4] recently discovered that critical bursts in filters follow a power-law and studied their statistical properties. With a theoretical model we investigated these erosive bursts using computer simulations [5] and found that they occur when the local fluid pressure overcomes the forces keeping deposited matter in place and blocked pathways get unclogged.…”

“…The experimental data stems from Ref [3]. and shows a jump in pressure loss caused by an erosive burst.…”

“…Parameter phase space diagram for adhesive coefficient ka and particle diameter d. The circles represent data from simulations, the data in between is interpolated. Since we change here the particle diameter, lengths are given in units of the pore diameter D, the pore length is L = 1.2[D].observations shown in the experimental work by Bianchi et al[3].…”

Episodicity and Migration of Low Frequency Earthquakes modeled with Fast Fluid Pressure Transients in the Permeable Subduction Interface

“…In the other mechanism, high fluid pressures induce fracturing and/or unclogging of small pores and pore throats. Impulsive flushing events have been observed in a variety of settings and have been called erosive bursts [16,54]. In this framework, mechanical forces caused by fast local pore pressure variations [85] and/or rupture of brittle heterogeneities [30,58] may be responsible for LFEs.…”