Optical Properties And Content Characterization Of Liquid Multicomponent Oil Mixtures

Water and petroleum resources are the lifeblood of human survival and the most important energy sources of national economy.Organic mixed pollutants in refined oil seriously affect the quality of surface water and groundwater,directly or indirectly affect human life and health;incorrect detection of mixed oil concentration in oil pipeline transportation and oil tank pollution will cause huge waste of resources and economic losses.Therefore,the realization of rapid identification and quantitative detection of product oil pollutants and real-time detection of contaminated oil section is of great significance and practical application value for the determination of pollution sources,the tracing of leakage liability,ensuring the safe storage and transportation of oil,and avoiding the loss of resources in contaminated oil section.In this paper,the inversion model of optical constants of single layer media was constructed by using optimization algorithm based on the results of Mie scattering simulation analysis,which lays a theoretical and technical foundation for the inversion model of liquid optical constants.In the quantitative and qualitative analysis of liquid multicomponent oil mixtures,the partial least squares method and principal component analysis method were used to establish quantitative and qualitative analysis models based on the environment of MATLAB.The main contents of this paper are as follows:1.The influence of particle scattering on the total transmittance of medium was investigated and used as the theoretical basis of scattering simulation analysis.According to the particle size distribution,the scattering type was distinguished by the particle size parameter,and the particles with different particle size parameter were simulated and analyzed,and the light loss under Mie scattering was investigated as the theoretical basis of the optical constant inversion model.2.A single-layer optical constant inversion model was constructed by combining the particle swarm optimization and spectral analysis method.The feasibility and stability of the model were verified by taking quartz glass as the research object.The experimental results show that both refractive index and absorption index have high accuracy,the maximum relative errors are 3.74e^-5%and 1.76e^-5%,respectively.The inversion model of liquid optical constants was corrected by using the optical constants of quartz glass,the feasibility and reliability of the model were analyzed with distilled water as the research object.The results show that the model can be used to solve the refractive index and absorption index of liquids,the maximum relative errors are 3.55%and 38.12%,respectively.3.Based on the refractive index pretreatment spectra,the interval partial least squares?iPLS?method was used to establish the quantitative analysis model for liquid multicomponent oil mixtures,and the M-D-iPLS-0.025 was determined as the best quantitative analysis model.Based on the principal component analysis?PCA?,the high-dimensional data distributed in multiple dimensions were projected onto several axes by using the idea of linear fitting.The qualitative analysis model for liquid multicomponent oil mixtures was established based on the refractive index spectra with Mahalanobis distance as the discriminant index.4.TU-1900 dual-beam ultraviolet-visible spectrophotometer,APTC-2 Peltier constant temperature controller and CH19-1 constant temperature cell holder were used to construct an non-normal temperature spectral measurement platform.The transmttance spectra of mixed oil samples were obtained in the temperature range of 20-70 C,and the influence of temperature on the optical properties of liquid multicomponent oil mixtures was analyzed.Then the suitability of quantitative and qualitative analysis model to extraordinary temperature conditions was investigated.Adaptability.The results show that the quantitative and qualitative analysis models have a certain adaptability to the disturbance caused by temperature change.The research results of this paper can provide theoretical basis and basic data for further research and development of real-time on-line monitoring technology for multicomponent oil mixtures in the future,and also provide new ideas for water quality monitoring and sewage discharge index analysis.