TRACING GENOTOXIC N-DBPs AFTER MEDIUM PRESSURE UV WATER TREATMENT BY NITROGEN LABELLING

摘要

Organic contaminant control is a major issue in advanced drinking water treatment. The presence of pesticides, endocrine disrupters and pharmaceuticals has caused PWN Water Supply Company North Holland in The Netherlands to implement multiple barriers in their surface water treatment plants. For improved organics control, a combination of advanced oxidation by medium pressure ultraviolet light in combination with hydrogen peroxide (MP UV/H2O2) treatment followed by granular activated carbon (GAC) filtration was implemented in 2005. The design of these processes was based on bench-scale and pilot-scale evaluations. In bench-scale experiments, dose-response relationships were established for these organic pollutants, and degradation at specific process conditions (i.e., 0.54 kWh/m~3 or 600 mJ/cm~2; 6 mg/L H2O2) was confirmed at the pilot-scale. Process conditions were based on 80 percent removal of atrazine, a pesticide. For a range of commonly found pesticides, such as 2,4-D, diuron and nicosulfuron, 80 percent degradation was also observed.