Effect of Fe, Mn oxides, residual chlorine concentration and shear stress on biofilm formation in drinking water distribution system

• Main Authors: Yang, Chi-Chang, 楊啟章
• Other Authors: Tsai, Yung-Pin
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/20688425332773853781

碩士 === 國立暨南國際大學 === 土木工程學系 === 93 === Drinking water is delivered to the users through the distribution system. It always makes the water to be deteriorated such as the increase of the pathogenic bacteria, while the biofilms are formed in the system. Therefore, the factors of iron, manganese, chlorine concentrations and shear stress were selected to simulate and investigate their impacts on the formation of biofilm within the distribution system in this study. The results of the study at non-chlorinated system showed that biofilm bacteria were increased with the increases of particle concentrations of iron and manganese and the shear stress. This phenomenon might due to the fact that the formation of iron and manganese particle provided larger locations for hiding the bacteria to adapt themselves to the environments. On the other hand, bacterial numbers of biofilm were decreased with the increase of the shear stress and independent with the concentration of Fe and Mn concentration at the chlorinated system. It implied that the increase of the shear stress promoted the penetration of chlorine into the inner parts of the biofilm and then inhibited the proliferation of the biofilm bacteria. The results of the particle monitoring system also showed that the increase of the effluent Fe and Mn concentrations was followed by the increase of the effluent particle numbers.