Li Y.,China University of Petroleum - Beijing |
Yang Y.,The Second Oil Production Plant of Daqing Oilfield |
Sun X.,China University of Petroleum - Beijing |
Sun X.,Petrochina |
And 5 more authors.
Journal of Petroleum Science and Engineering | Year: 2014
The normal optical microscope image of fluorescence analysis is used as the traditional method to analyze remaining oil distribution, but it has limitations such as poor clarity, low resolution, unobvious color distinction between oil and water, unclear oil-water interface and cannot make quantitative research about the types and content of the remaining oil. With the improved fluorescence microscope and frozen slice of cores, the laser scanning confocal microscopy method (LSCM) for remaining oil analysis has the ability to determine clearer images, so it can clearly distinguish the oil-water interface, intuitively display the mineral form and microscopic remaining oil distribution. Based on this, the self-developed software can quantify the remaining oil content and total amount of oil and water. When the sample is representative and there are enough slices, the result can reflect remaining oil distribution of the selected oilfield area. With the help of fluorescence detecting technology and stratified scanning, LSCM can give the ratio of light and heavy oil in remaining oil, and quantitatively describe the distribution of light and heavy oil, and give the 2D and 3D distribution maps of oil and mineral and provide the feature of oil and water in rock pore to a more clear extent. Through 3D image reconstruction of scanned real sample, the porous media and oil distribution can reappear. In this paper, we introduce a new method, the LSCM, for analyzing remaining oil distribution. The comparison of this new method and the traditional method shows that the new method has advantages like clear image, consecutive scanning, image reconstruction, multiple labeling technique and quantitative analysis. This method was applied to an oilfield to study microscopic remaining distribution in different layers of the reservoir. By analyzing the experiment data, we discuss the remaining oil distribution after using different displacing agents, and the effects of different displacing agents on light and heavy components of oil. The reconstructed 3D image can provide useful guidelines and suggestions for the remaining oil production. © 2014 Elsevier B.V.
Li R.,Petrochina |
Zhang J.,Northeast Petroleum University |
Zhang C.,Petrochina |
Zhang H.,Northeast Petroleum University |
Qu P.,The Second Oil Production Plant of Daqing Oilfield
Applied Mechanics and Materials | Year: 2013
Layer system subdivision and adjustment is applied in oilfield development to ease the contradiction in inner-layer and interlayer and implement separated layer water flooding well, which is a major adjustment measure to improve developing effects. YSL is a typical low-permeability oil field, whose petrophysics is poor, and which exist many problems, such as apparent contradictions between layers, and poor development effects through separated zone water injection and so on. In this article, the thickness of barriers, injection profile, permeability contrast and remaining oil distribution are analyzed comprehensively. So a reasonable method is also proposed. Much weakness that factors are not comprehensive in adjustment method and that the problems in the development process are not accurately reflected is overcome, which exists in the past methods. The adjustment means can utilize poor thin layers better, reduce invalid water injection and ease the contradictions between layer, and oilfield development effects are improved eventually. It is a reference and guidance for other blocks or oilfield which exist the same problems. © (2013) Trans Tech Publications, Switzerland.
Jia L.-Z.,The Second Oil Production Plant of Daqing Oilfield |
Zhang C.-L.,The Second Oil Production Plant of Daqing Oilfield |
Bai Y.-P.,The Second Oil Production Plant of Daqing Oilfield |
Chu M.-Y.,The Second Oil Production Plant of Daqing Oilfield |
And 3 more authors.
Shiyou Huagong Gaodeng Xuexiao Xuebao/Journal of Petrochemical Universities | Year: 2010
Because of the low viscosity of the solution prepared by common produced water, the oil recovery was not high. Therefore, the solution has to be prepared with tap water or other water of high quality, which leads to high consumption of fresh water. Produced water after aeration was used to prepare hydrolyzed polyacrylamide (HPAM) or alkaline-surfactant-polymer (ASP) solution. The thermal stability of the prepared solutions was investigated. The influences of shear, sulfate-reducing bacteria (SRB), the alkali and the viscosity stabilizer on the solution viscosity were also investigated. The experiment results show that shear degradation is the major factor in viscosity loss of the solutions and the aeration had good effect to reduce the viscosity loss caused by SRB. The experiment results also show that the HPAM solution has a better capability to keep viscosity in the presence of viscosity stabilizer when it is subjected to 30-day aging, and so do the ASP solution when alkali and viscosity stabilizer are present.