LABORATORY TESTING OF ACID OIL-DISPLACING COMPOSITION TO ENHANCE OIL RECOVERY

The article presents the results of laboratory tests of an acid oil-displacing composition based on a surfactant developed at the Institute of Petroleum Chemistry of the Siberian Branch of the Russian Academy of Sciences to enhance oil recovery. The experiments were carried out on a installation to study the filtration characteristics of heterogeneous reservoir models. It was found that the use of the composition leads to a significant increase in the oil displacement coefficient.

EOR Technologies: Physico-Chemical Aspects

<p>The application of self-regulating oil-displacing systems is considered to be a promising trend in the development of physico-chemical EOR methods. Technologies intended to increase conformance predominate. EOR technologies, where heat energy of the formation is used to generate alkaline buffer systems, CO₂ and gels increasing oil displacement and conformance, have wide potentialities. Such methods have been realized in the technologies developed at the Institute of Petroleum Chemistry SB RAS (IPC). Hydrolysis, hydrolytic polycondensation and coagulation in the system carbamide – aluminum salt – surfactant – water is the physico-chemical base for the technologies involving alkaline buffer systems, CO₂ and inorganic gels. To prepare thermoreversible polymer gels one uses change of phase from solution to gel in the system: cellulose ether with a lower critical dissolution point – water. Presented are the results obtained on the application of physico-chemical EOR methods and technologies developed at IPC in oil fields of Russia. The technologies proved to be economically effective and environmentally safe. The period of payback is 5-12 months.</p>

Spatial Variability of Chemical Composition of Eurasian Oils

The study of relationships governing the variability of chemical composition of the Eurasian oils has been carried out on the basis of the statistical processing of the data on contents of total sulfur, resins,<br />paraffin wax and asphaltenes in oils. These indices are considered as the principal chemicals of oils chemical composition. The data processed for Eurasian continent was chosen from database on petroleum chemistry, which is create by Institute of Petroleum Chemistry of Siberian Branch of Russian Academy of Sciences and nowadays includes more than 9,000 entries of oil physical-chemical data on all main world oil-bearing basins. Latitudinal and longitudinal dependencies of the above indices of oils chemical composition were studied by methods of statistical and cluster analyses and means of geographical information system (GIS) ArcView 3.1. The results of these studies are represented on the computer maps. It is shown that properties of oils are statistically inhomogeneous in Eurasia depending on geographic position. In average, contents of total sulfur, resins and asphaltenes in crude oil increase in direction from<br />east to west. But the analysis doesn’t reveal longitudinal dependence of paraffin content, only a latitudinal dependence. In average, paraffin wax content in oils increases in direction from north to south. From the<br />analysis of the results of geozoning of oil-bearing territories using the whole complex of indices, the zones of oils that are homogenous by their properties was revealed. The results obtained may be used to solve the<br />problems of a rational use of hydrocarbon resources, in particular:<br />a) siting the oil-refining and petrochemical enterprises, b) developing the regional nets of a rational transporting of hydrocarbons and petroleum products.