Consideration of the Principles for Stabilizing and Increasing Oil Production at the Later Stage of Field Development (on the Example of Ukraine Fields)

The object of research is the oil industry. One of the most problematic issues in the industry is the transition of deposits to a late or final stage of their development. A significant number of deposits in Ukraine, USA, Russia, Poland, Azerbaijan began to be developed in the middle of the 19th century. To date, all the «old» fields are mostly depleted both in terms of hydrocarbon reserves and energy potential (reservoir pressure), and some are still in development, but in the so-called «late stage». At the same time, a significant number of relatively «young» fields have also entered the late stage of development, which is characterized, first of all, by a significant production of oil reserves, a progressive increase in water cut in wells, and an increase in the share of hard-to-recover reserves. As well as the transition to mechanized methods of oil production and the gradual increase in the stock of marginal wells, physical and moral deterioration of fixed assets of oil production with the threat of their mass retirement, deterioration of the ecological balance of the environment, and the like. Therefore, this work is devoted to the consideration of the principles of stabilizing and increasing oil production at a late stage of field development (using the example of Ukrainian fields). In the process of research, the original methods of classical scientific research were used, the main of which are analysis and synthesis, induction and deduction. An example of this is the proposed distribution of the structure of oil reserves into active and hard-to-recover ones. The study is based on statistical processing of a significant array of real information about the state and problems of oil production, which is typical and characteristic not only of Ukrainian fields. A wide range of directions for investment activities in the field of oil production was obtained. These are, mainly, directions for increasing the resource base, enhancing the completeness of its production, organizing a controlled and controlled displacement of oil by water, including with the use of «reverse» technology, unification of equipment for oil production, and ensuring environmental protection. Owing to the comprehensive application of these investment directions for improving the systems of field development at a later stage, it is possible to stabilize and gradually increase production, the value of which is determined by the relevant design documents

Selection of Effective Methods of Increasing Oil Recovery in Dealed Fields Based on Retrospective Analysis

The object of research is methods of increasing oil recovery in «old», depleted oilfields. One of the main tasks of the oil-extracting industry in any country in the world was and still is ensuring the project level of oil production at the maximum possible coefficient of its extraction from the subsoil. In this case it is extremely important to study and use technological methods and means of acquired experience in oilfield development. The paper considers the historical aspects of the development of stabilization and oil recovery methods from 1770s to the present day on the example of Ukrainian oilfields. In parallel with the history of the implementation of methods, their physical and technological content and conditions of application are discussed. Of all the methods used to increase the level of oil production, the most effective ones, which have found application at certain stages of the Ukrainian oilfields' development, are considered. This is, first of all, a vacuum process, areal flooding, cyclic flooding, gas and water-gas repression, injection of surfactants, surfactant polymer-containing systems, polymer flooding, horizontal branched drilling. The methods development analysis is considered against the background of their geological and industrial acceptability and obtaining technical and economic effects. Based on the results of the study, a group of methods has been identified. These methods are advised to apply in geological and industrial conditions, similar to those described, which should ensure the expected efficiency. Undoubtedly, along with this, it is advisable to use the methods of mathematical modeling of oilfield development processes. Proposals are formulated on the conditions and principles of applying the methods under consideration in order to improve the systems for the development of oilfields. It has been established that the most acceptable methods of increasing oil recovery in depleted oilfields are the injection of surfactant solutions both independently and together with an aqueous solution of polyacrylamide, creation of gas-water repression and polymer flooding, in which preference is given to AN132SH and AN125SH reagents of FLOPAAM S series from SNF FlOERGEL

Перспективи використання випарних охолоджувачів в енергетичних системах

The conception of creating the multi-stage evaporated gas and liquid coolers on the basis of monoblock multichannel structures is developed. On the basis of the received experimental material the possibility analysis of such coolers is carried out.Разработана концепция создания многоступенчатых испарительных охладителей газов и жидкостей на основе моноблочных многоканальных насадочных структур. На основании полученного экспериментального материала выполнен анализ возможностей таких охладителей.Розроблена концепція створення багатоступінчастих випарних охолоджувачів газів і рідин на основі моноблокових багатоканальних насадкових структур. На підставі отриманого експериментального матеріалу виконано аналіз можливостей таких охолоджувачів

Development of TECHNOLOGY of Gas Condensate Extraction From the Formation in the Conditions of Retrograde Condensation

The object of research is gas condensate fields at a late stage of their development under conditions of a decrease in reservoir pressure below the pressure of condensate separation from a gaseous state. Reservoir losses of condensate during the development of deposits in depletion mode can reach 78 %, which entails the need to use various methods of stimulating the reservoir system to remove it. The most acceptable method is the use of a cycling process by re-injection (recirculation) of the produced and separated gas into the formation. A significant disadvantage of the cycling process is the long-term conservation of gas reserves as a result of its re-injection into the reservoir and significant capital and operating costs for dry gas injection. From a technological point of view, the use of the cycling process is constrained by the low value of the sweep efficiency. Dry gas that is injected has a lower viscosity in terms of the gas-condensate mixture is withdrawn from the reservoir, and under the conditions of the heterogeneous structure of the reservoir, its rapid breakthrough from injection to production wells takes place and, as a result, a decrease in the efficiency of condensate recovery. As an alternative to the cycling process for extracting retrograde condensate from the reservoir, it has been proposed to squeeze it out with water. The paper proposes a unified waterflooding system, actually displacing condensate with water or a gas-water mixture. This is achieved by controlled operation of injection and production wells. First, gas is taken from the wells, and with the appearance of water in the product, methods of intensifying the transfer to the surface are used. If necessary, the wells are switched to forced production mode. The results of laboratory studies carried out on real samples of core material from the Andriyashivske gas condensate field (Ukraine) are presented. The directions of the implementation of gas-water repression in gas condensate fields with the parallel use of restrained reservoir gas available in the reservoir are substantiated. The technology allows to extract up to 50 % of the condensate dropped out in the reservoir

Development of TECHNOLOGY of Gas Condensate Extraction From the Formation in the Conditions of Retrograde Condensation

The object of research is gas condensate fields at a late stage of their development under conditions of a decrease in reservoir pressure below the pressure of condensate separation from a gaseous state. Reservoir losses of condensate during the development of deposits in depletion mode can reach 78 %, which entails the need to use various methods of stimulating the reservoir system to remove it. The most acceptable method is the use of a cycling process by re-injection (recirculation) of the produced and separated gas into the formation. A significant disadvantage of the cycling process is the long-term conservation of gas reserves as a result of its re-injection into the reservoir and significant capital and operating costs for dry gas injection. From a technological point of view, the use of the cycling process is constrained by the low value of the sweep efficiency. Dry gas that is injected has a lower viscosity in terms of the gas-condensate mixture is withdrawn from the reservoir, and under the conditions of the heterogeneous structure of the reservoir, its rapid breakthrough from injection to production wells takes place and, as a result, a decrease in the efficiency of condensate recovery. As an alternative to the cycling process for extracting retrograde condensate from the reservoir, it has been proposed to squeeze it out with water. The paper proposes a unified waterflooding system, actually displacing condensate with water or a gas-water mixture. This is achieved by controlled operation of injection and production wells. First, gas is taken from the wells, and with the appearance of water in the product, methods of intensifying the transfer to the surface are used. If necessary, the wells are switched to forced production mode. The results of laboratory studies carried out on real samples of core material from the Andriyashivske gas condensate field (Ukraine) are presented. The directions of the implementation of gas-water repression in gas condensate fields with the parallel use of restrained reservoir gas available in the reservoir are substantiated. The technology allows to extract up to 50 % of the condensate dropped out in the reservoir