Detection Technology Research Of Trace Mineral Oil In Water Based On Fluorescence Spectrum

As the exploitation and consumption of petroleum resources in the world is getting bigger and bigger,more and more oily sewage is discharged in the process of industrial and agricultural production,which makes the improvement of the content of trace mineral oil in the marine and terrestrial environment and does harm to people and the surrounding ecological circle of healthy development.Therefore,in order to solve the problem of water pollution,it is of great significance to determine the trace mineral oil in water efficiently and accurately.At present,there are many kinds of methods to measure the content of organic compounds in water.According to the determination of the concentration and composition of trace mineral oil in water,the conventional detection method is difficult to realize the precise measurement in the choice of the feasible plan.To solve this core problem,in this paper we describe a new method to detect oil pollutants based on three-dimensional fluorescence spectrum.By combining the extraction of sensitive characteristic parameters in fluorescence spectra and dual tree complex wavelet denoising,we can detect the fluorescence signal of oil pollutants accurately.Based on the Lambert-Beer law,analyse two-dimensional fluorescence spectral characteristics of oil substances,deduce numerical relationship with the oil intensity of the fluorescence signal between the sample concentration.Defects demonstrate traditional 2D fluorescence spectroscopy assay,make theoretical explanations detection mechanism of three-dimensional fluorescence spectrometry.Research on the use of three-dimensional fluorescence spectrum of oil pollutants Oil Identification and measurement methods.Three-dimensional fluorescence spectroscopy is a new fluorescent signal detection technology,three-dimensional spectra measured substances containing more substantial than the two-dimensional spectrum of information,It has greater capability in the fluorescence signal processing.Develop means based on the detection of three-dimensional fluorescence spectra of oil pollutants.Make apparatus theoretical argument of the major components.Selecthigh-power,wide spectral range pulsed xenon lamp as the excitation source and blazed diffraction grating as spectroscopic devices.Select high sensitivity,high dynamic range CCD device as the photoelectric converter.Fluorescent signal transmission using low-loss quartz fiber as a medium,design preamplifier circuit and filter circuit photoelectric for signal preprocessing.Since the fluorescence signal is very weak,and easy to drown in the background noise,this design based on Boxcar sampling integration circuit to accurately extract the fluorescence signal.Put forward the method of turning three dimensional spectral data down into a two dimensional spectrum,and calculating the two dimensional fluorescence spectrum envelope to simplify the fluorescence spectrum data processing.Research oil pollutants apparent features of two-dimensional and three-dimensional spectral statistics,choose standard deviation,kurtosis coefficient and asymmetry coefficient as characteristic statistics.Using multivariate statistical analysis method combining with spectral data dimension reduction method,research the mixture of gasoline,kerosene,diesel oil experiment,and compare with the parallel factor analysis method.The results show that the method of multivariate statistical analysis combined with spectral data dimension reduction method has high resolution and the recovery rate of concentration in the oil mixture,and the implementation of the variety of oil pollution accurate recognition and precise detection of concentration.For weak fluorescence signals in background noise,it proposes the dual tree complex wavelet transform coupled with Shannon entropy threshold as fluorescence signal denoising algorithm for oil pollutants.Db7 wavelet was selected as the wavelet basis function by experiment.Numerical comparison between traditional wavelet transform denoising method and the proposed signal denoising method based on dual tree complex wavelet transform coupled with wavelet Shannon entropy threshold was made to validate the separation effect of dual tree complex wavelet transform denoising method.