Application Of NMR Techniques On Analysis And Exploration Of Crude Oil

An understanding of the chemical composition and physical properties of crude oil is important for the petroleum and petrochemical industries. The physical and chemical properties of crude oil depend on the type and relative amount of hydrocarbons present. When it is not possible to elucidate the exact composition of the oil, the"average structural information"may be a meaningful concept for the description of the bulk properties of the oil.Nuclear magnetic resource(NMR) is an important tool in the research of the physical-chemical properties of crude oil. The application of NMR has been extended by the use of 2D ¹³C-¹H J-resolved spectroscopy (HET-JRES) to obtain the average structural information of the crude oil. The approach can separate the scalar coupling (¹JCH) and chemical shifts into the two dimensions of a 2D NMR spectrum. It has been demonstrated that phase sensitive 2D ¹³C-¹H J-resolved NMR spectroscopy (HET-JRES) can be used to quantitatively analyze the contents of the C, CH_, CH₂ and CH₃ groups in crude oil. This makes it possible to estimate the molar concentration of the different CH_n spin systems in the sample. It was demonstrated here that the structural information, derived from HET-JRES, showed good linear relationships with the density and viscosity of the crude oils, and the correlation coefficients were greater than 0.94. The HET-JRES method can therefore be used as an alternative way to predict those physical properties of the oil. If the sample is properly prepared, the internal standard may be not necessary.Nuclear magnetic resonance (NMR) log is one of the great progresses of well logging techniques. For the purpose of the application of NMR log in geological interpretation, the laboratory study of the NMR parameters of various formations has been carried out.The NMR property of rock and the interpretation models of NMR log data have been studied. The NMR porosity, permeability, the T_2cutoff values and other parameters of...