Three-dimensional Fluorescence Spectrum Detection Method For Measuring The Concentration Of Organic Pollutants In Water

It is important to detect organic pollutants concentration for monitoring water quality in sewage water. Chemical method as the traditional detected method cannot be applied to online monitoring the sewage water, because this method is the time-consuming longer and easy to cause secondary pollution. In this case, three-dimensional fluorescence spectroscopy is considered, because it has many advantages such as much more information, faster test speed and high sensitivity, and it has been widely used in food safety, medicine and other areas of fingerprint identification. In the paper, a sewage model based on the three-dimensional fluorescence spectra and comprehensive index of the organic pollutant concentration is presented. Mainly for the following areas:(1) Some water samples are got from three settling tank in HengDian sewage treatment plant and then the data of the three-dimensional fluorescence spectra is obtained.(2) Lots of methods are used to pretreatment the spectra to eliminate interference effects of light and get the smoothing preprocessing of the spectra, in which the interpolation method can effectively remove the Rayleigh scattering and three times a polynomial smoothing preprocessing can improve signal to noise ratio.(3) The model based the three-dimensional fluorescent full spectrum data is presented to predict sewage organic pollutants composite index.To obtain the model, the following methods are used:the two-dimensional modeling method such as partial least squares, principal component regression, and the three-dimensional modeling method such as parallel factor algorithm, multi-dimensional Partial Least Square. The predicted results from these method models are analyzed to research the modeling effect and influence factors of these methods.(4) Based on partial regression method, classification method based on the sample source used, Euclidean distance classification method based on three-dimensional fluorescence spectra, and feature selection method based on the three-dimensional fluorescence spectra and comprehensive index of the organic pollutant concentration in the correlation coefficient are selected to build the model. The results show that the correlation coefficient for feature selection method is better and can get higher accuracy.