2010 Volume 8 Issue 1 Pages 17-28
The quantitative and qualitative evolution of dissolved organic matter was followed at different stages of water treatment and in tap water to assess dissolved organic carbon (DOC) removal. Both DOC and 3- dimensional excitation emission matrix (EEM) fluorescence spectroscopy were used to evaluate the efficiency of the process. On the average, 53% of DOC was removed during the treatment process at the treatment plant. After water released in the distribution system, an increase of 27% DOC was observed in tap water, suggesting a production of organic carbon within the network. The EEM permitted to distinguish three main fluorophores, tryptophan-like (T) and humic-like (A and C) in raw water as well as in treated water. In tap water, an increase of fluorescence intensity (FI) was also observed, 31%, 34% and 59% on the average for fluorophores A, C and T, respectively. The tryptophan-like fluorophore is related to microbial activities and suggests an important development of microbial community within the distribution system due to the inefficiency of organic matter removal during the water treatment process.
