LUKoil: Enhanced Oil Recovery
Crude oil production from the Korchagin oil field in the Caspian Sea started in 2010. The oil field will be developed with super-long horizontal wells of over 5 km, a unique engineering design solution for Russia. The simultaneous drilling of all oil-bearing strata will be achieved through a uniform radial distribution of wells. The method of monitoring drilling operations is also unique in Russia. Data from the registration systems, installed on an offshore drilling rig, will be transferred to our Astrakhan office via a satellite communication channel in real-time. Consequently, our onshore specialists will have the opportunity of monitoring the drilling process online.
The introduction of innovative sidetracking technologies for old wells and the selection of hydraulic fracturing technologies in Western Siberia has enabled LUKOIL OJSC to increase oil production from the Achimovsky oil deposits from 100 thousand tonnes per year to almost 1 million tonnes within seven years and to double the reserves.
In the Perm Region, an industrial development programme for the oil reserves lying beneath the potassium-magnesium salt deposits of the unique Verkhnekamsk oil field has been used on the basis of modern drilling technologies and the safe operation of extended-reach horizontal wells. This has enabled over 100 million tonnes of previously unreachable reserves buried deep in the earth to be brought into production.
In the Timan-Pechora oil-and-gas province, the industrial application of heat-gravitation drainage technologies for the development of high-viscosity oil deposits has made it possible to increase the production of the oil raw-materials base by 300 million tonnes and has significantly improved the industrial and environmental safety of the production process.
In Saudi Arabia, LUKAR, a JV of LUKOIL and Saudi Aramco, carried out the world’s deepest hydraulic fracturing at a depth of 5,500 metres. For the first time ever in Saudi Arabia, LUKAR applied 11¾ inch columns to close off a lost circulation zone and used multi-pack assemblies for well testing.
One of the Company’s most prominent achievements in the development of new technologies is its ambitious use of methods for intensifying oil production and enhanced oil recovery (EOR). These methods allow for a significant increase in recoverable reserves and oil production, and encourage the industrial production of high-viscosity/Heavy oil reserves which are hard to recover and originate from low-permeability reservoirs at the later stages of field production. In recent years, the LUKOIL group’s share of oil production, based on the use of various oil-field technologies, reached over 20% of the total volume produced. The Company applies physical, chemical, hydrodynamic and thermal methods of impact on production reservoirs.
In 2009, the Group performed 5,098 EOR operations, 300 fewer than in 2008. However, incremental ultimate recovery was higher compared with 2008. In the reporting year, incremental ultimate recovery due to the use of ORI methods accounted for 23 million tonnes, or 25% of the Company’s total oil production in Russia.
In 2009, 634 EOR operations with an average yield increase of 9.6 t/d were performed in LUKOIL’s oil fields. Volumes and operational efficiency on hydraulic fracturing in 2009 are comparable to the corresponding figures in 2008.
In 2009, some of the Company’s specialists were awarded the Diploma of Federal Authorities on Intellectual Property, Patents and Trade Marks (RUSPATENT) for the nomination “100 Best Russian Inventions” for inventing the method of Local Directional Hydraulic Fracturing of Oil or Gas Deposits. This method is used to improve the production output of oil, gas and gas condensate fields, in particular at the later stage of well development, which is characterised by a high water cut level and the presence of stagnant and blind zones, making oil extraction impossible by conventional methods. 9 million tonnes of oil were produced owing to the use of other EOR methods, such as hydrodynamic, thermal and chemical techniques and well stimulation. In 2009, the ambitious introduction of chemical technologies continued, which allowed for the achievement of an incremental ultimate recovery of 1.9 million tonnes (an increase of 18%), while the number of operations remained practically the same: 1,357 in 2009 and 1,324 in 2008.
Sidetracking on existing wells is another highly efficient EOR method. In the reporting year, active sidetracking continued. There were 264 sidetracked wells (vs. 260 a year earlier) with an average yield increase of 16.8 t/d. In 2009, the Company retained sidetracking scopes at the level of the previous year despite a general cutback in the investment programme. It is worth mentioning that sidetracking is used with the aim of recovering remaining reserves, mainly from the stock of inactive wells which have been in development for long periods and are characterised by highly depleted active reserves and a high water content in the recovered oil.
To increase the efficiency of oil production, a method of extended reach drilling is used, which provides for a production growth of 1.5 – 2 times. In 2009, a new 91st lateral well was put into operation with an average yield of 78.2 t/d, which is twice as high as the yield of conventional wells.
The Company ambitiously develops and applies new technologies for the production of high-viscosity oils. The latest domestic experience in the development of high-viscosity oil reserves was gained in the Republic of Komi, where LUKOIL developed the Jaregsky and Usinsky fields with initial geological heavy oil reserves of over 1 billion tonnes, according to the Russian classification. Thermal methods of EOR are used in both fields and the production rate is over 2.2 million tonnes per year, which comprises two thirds of the total heavy oil yield in Russia. The permo-carboniferous deposits of the Usinsky field are developed using thermal steam and cyclical steam pattern drive technologies. In recent years, successful work on improving efficiency in the application of thermal technologies in the system of vertical wells continued. Furthermore, the development of combined steam cycle treatment (SCT) technologies continues and the development of well stimulation using the simultaneous injection of a heat transfer medium. The displacement of oil composition started with the introduction of new thermal technologies, such as thermal steam technologies, into the system of lateral wells, perpendicular thermal gravity drainage technologies, EOR technologies for lateral wells, straight wells with radial bends, the whole production section and steam oil displacement technologies.
The Jaregs field is developed on the basis of thermal mining technology. Surface production is at the pilot production stage. In 2009, operations based on thermal gravity drainage technology were carried out for the purpose of organising the efficient surface production of oil on the Jaregsky field’s pilot site. In 2010, work will start on injection and lateral well production. Steam injection is planned as from 2011.
Several years ago, one of LUKOIL’s specialists developed a new reacting substance, RITIN-10, to improve the oil production rate of non-uniform terrigenous carbonaceous flooded deposits in the extreme water cut conditions at the late stages of oil field development. 1,002 wells were processed in 8 years, resulting in an additional yield of 1,300 tonnes of oil. The average operational benefit comes to 1,296 tonnes per well, and in some cases reaches 5,500 tonnes of additionally produced oil with an average return on investment time of between several weeks and three months. Various modifications of the reacting substance RITIN-10 were developed for repair and insulation operations, and to improve oil production. A project for the marketing of this reacting substance includes the establishment of a joint venture for large capacity production and of a service infrastructure for customer support.
