Accumulation and modeling of particles in drinking water pipe fittings

Abstract

The effect of pipe fittings – mainly T-pieces – on particle accumulation in drinking water distribution networks is shown in this work. The online measurements of flow and turbidity for cast iron, polyethylene and polyvinylchloride pipe sections have been linked with the analysis of pipe geometry. Up to 0.29 kg of the total mass of particles was found to be accumulated in T-pieces ranging from DN 100/100–DN 250/250. The accumulated amount of particles in the fittings was defined as <i>J</i> and introduced into the existing turbidity model PODDS (Prediction of Discolouration in Distribution Systems) proposed by Boxall et al. (2001), which describes the erosion of particles leading to discoloration events in drinking water networks, viz. sections, of straight pipes. It does not interpret the mobilization of particles in pipe fittings, however, which have been considered in this article. T-pieces were the object of this study and depending on the diameter or daily flow velocity, the coefficient <i>J</i> varied from 1.16 to 8.02

The action of chemical and mechanical stresses on single and dual species biofilm removal of drinking water bacteria

“…The shear stress values tested in the present study complements previous reports about mechanical removal of biofilms (Husband and Boxall, 2011;Mathieu et al, 2014;Neilands et al, 2012). It is clear that biofilm removal is not proportional to the shear stress increase.…”