Laboratory Testing of Thermo-chemical Schemes for Carbonate Heavy Oil Reservoirs
S. Ursegov and E. Taraskin
Event name: IOR 2017 - 19th European Symposium on Improved Oil Recovery
Session: Poster Introductions 3
Publication date: 24 April 2017
Info: Extended abstract, PDF ( 1.21Mb )
Price: € 20
The objective of this work is the Permian - Carboniferous reservoir of the Usinsk field located in the Timan-Pechora province of Northwest European Russia. The oil-producing rocks are the naturally fractured limestones and dolomites. The live oil viscosity is equal to 1240 mPa*s. In the reservoir, there is a steam injection at ~300°C and ~10 MPa. The current oil recovery numbers are estimated between 8 - 10 %. These oil recovery efficiencies could be improved with the injection of suitable chemicals to increase the water wettability of the reservoir matrix. In order to justify a package of measures aimed to increase the reservoir oil recovery factor, special laboratory studies were carried out with the help of hot water and steam injection thrown the stacked models of full-sized and standard-sized core samples. In addition, the experiments of heavy oil extraction by hot water in combination with surfactants were conducted. This work summarizes the results obtained during the laboratory tests. The combined use of hot water and the NOP surfactant increases the oil recovery factor up to 38 %. However, the oil-wet characteristic of the reservoir rocks did not modified even upon their heating up to the temperatures of 100 – 2500C.