The Effects of Flushing on Water Quality and Biofilm Biomass in Different Daily Flow Patterns of Distribution System

Abstract:

We studied the effects of flushing on water quality and biofilm biomass in different daily flow patterns of distribution system. After building up steady biofilm layers in two flow velocity (0.25 m/s and 0.65 m/s) distribution systems consisting of PE pipe, then flushed by stepwise increased flow velocity. An increase flow velocity caused an immediate increase in turbidity and heterotrophic bacteria of water as a result of detachment of biofilms in the pipes, especially in low flow patterns distribution system. Three days later after flushing, water quality of two systems were generally lower and more stable than before flushing. Flushing strategies only limited biofilm growth to a certain extent and did not completely eliminate microorganisms from the systems.The low flow velocity distribution system was easily being disturbed by flushing.

• Periodical: Advanced Materials Research (Volumes 1030-1032)
• Pages: 330-333
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1030-1032.330
• Online since: September 2014
• Authors: Ze Bing Zhu, Chen Guang Wu, Dan Zhong*, Yi Xing Yuan, Li Li Shan, Jie Zhang
• Keywords: Biofilm, Flow Velocity, Flushing, Water Distribution System, Water Quality

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