Monitoring of Dissolved Organic Carbon (DOC) in a Water Treatment Process by UV-Laser Induced Fluorescence

Results of online investigations of water quality during a water treatment process by ultraviolet-laser-induced fl uorescence (UV-LIF) are presented. In the fi rst part the integrated fl uorescence intensity is correlated to the classically deter- mined concentration of dissolved organic carbon (DOC). Decision, detection and determination limits are evaluated for this procedure and online DOC measure- ments conducted with the presented LIF system are compared to reference analysis. In the second part the ozone demand in the water treatment process is derived from the LIF-signal directly. The calibration was done by correlating LIF-signals with the ozone doses for different conditions and a defi nite residual ozone concentration in the processed water.