System Analysis of Oilfield Development Problems in Environmentally Sensitive Areas

The goal of oil and gas field development is to maximize the benefits of exploitation work. In some large oilfields entering the mid-to-late development stage, to maximize the input-output ratio of oilfield exploitation, in oilfield development work, you will receive Due to the influence of many interference factors, in the field of oilfield exploitation, it is necessary to reduce the economic cost of oil and gas field exploitation as much as possible and continuously improve the economic benefits of oilfield mining units. In the mid-to-late production of oil and gas fields, the use of big data to establish a reasonable and scientific production plan for oil fields and an effective decision support system provide an important guarantee for the development and production of oil and gas fields in the middle and late stages. Through the use of effective production-increasing technology and production decision-making, comprehensively consider some oilfield mining areas and newly-added resource mining areas, comprehensively optimize and set up the development of oilfield resources in the middle and late stages and use big data technology to develop oilfields. Among them, the resource advantages are effectively transformed into economic advantages, in order to provide a good work plan for the middle and late stages of oilfield development.

Decisions conserning development and depletion of petroleum reservoirs must be made under uncertainty in the decision supporting information. The incomplete knowledge of the reservoir charactistics contributes significantly to this uncertainty. In addition, and this is particularly true for improved oil recovery (IOR) projects, the uncertainty in the operational environment makes hard to confirm and substantiate research efforts. To address these issues a multicriterion model is introduced. The model is coupled with a reservoir simulator and is used to estimate the applicability and efficiency of various field development strategies. The multicriterion model used here applies the methods of interval theory and fuzzy set logic. It permits the integration of geophysical data, the potential efficiency of various IOR methods and other resource requirements. A pre-modelling multicriterion analysis is used to optimize field scale reservoir simulations for IOR methods. Particular field case scenarios show how the reservoir description information and IOR experience and knowledge can be used for decision making support. This work demonstrates that a first-order screening decision making system combined with a field scale reservoir model can be used to further optimize the recovery while reducing the costs and uncertainty in the decision making.

As an essential resource in the process of national economic development, oil and gas has a very important strategic position. As a non-renewable resource, various countries and regions attach great importance to the development and use of oil and gas resources. Generally, oil and gas resources are buried deep underground and are the most critical resources in geological exploration. Reservoir development is a very important work, in the development process involves a lot of professional content, if the development is not reasonable, there will be some geological problems. Therefore, this paper chooses reservoir engineering geological problems in oil and gas field development as the research object, first expounds the impact of reservoir geological characteristics on oil and gas field development, then analyzes the existing problems, and finally proposes corresponding solutions to improve the quality and efficiency of oil and gas field development.

CO2 flooding, as a commonly employed enhanced oil recovery (EOR) method today, is characterized by high oil displacement efficiency, environmental friendliness, and economic viability, and has been extensively developed and applied in oil and gas field development. During CO2 flooding operations, gas channeling frequently occurs within the reservoir due to significant permeability contrasts arising from formation heterogeneity, coupled with the low density and viscosity of CO2. This phenomenon can adversely affect the normal productivity of oil wells. With the advancement of CO2 flooding technology, the effective prevention of CO2 channeling has become crucial for improving oil recovery. Gel particle plugging systems, being economically viable and efficient, exhibit favorable stability, adaptability, and strength, leading to significant applications in oilfield development and demonstrating promising prospects for future development. This paper comprehensively reviews the classification and developmental status of gel particle systems used for channeling control in CO₂ flooding. It introduces the mechanisms of several gel particle types, including preformed particle gel, polymer microspheres, and dispersed particle gel, and examines their current development status both domestically and internationally. Furthermore, future research directions and application prospects are discussed.

Geophysical logging curves are crucial for oil and gas field exploration and development, and curve reconstruction techniques are a key focus of research in this field. This study proposes an inversion model for deep resistivity curves in marine carbonate reservoirs, specifically the Mishrif Formation of the Halfaya Field, by integrating a deep learning model called CNN-GRU-ATT, which combines Convolutional Neural Networks (CNN), Gated Recurrent Units (GRU), and the Attention Mechanism (ATT). Using logging data from the marine carbonate oil layers, the reconstructed deep resistivity curve is compared with actual measurements to determine reservoir fluid properties. The results demonstrate the effectiveness of the CNN-GRU-ATT model in accurately reconstructing deep resistivity curves for carbonate reservoirs within the Mishrif Formation. Notably, the model outperforms alternative methods such as CNN-GRU, GRU, Long Short-Term Memory (LSTM), Multiple Regression, and Random Forest in new wells, exhibiting high accuracy and robust generalization capabilities. In practical applications, the response of the inverted deep resistivity curve can be utilized to identify the reservoir water cut. Specifically, when the model-inverted curve exhibits a higher response compared to the measured curve, it indicates the presence of reservoir water. Additionally, a stable relative position between the two curves suggests the presence of a water layer. Utilizing this method, the oil–water transition zone can be accurately delineated, achieving a fluid property identification accuracy of 93.14%. This study not only introduces a novel curve reconstruction method but also presents a precise approach to identifying reservoir fluid properties. These findings establish a solid technical foundation for decision-making support in oilfield development.

In the world, with the development of science, brand new technologies are being created to generate energy resources (e.g., hydrogen energy, electric car, etc.). These inventions will reduce the consumption and cost of hydrocarbon resources. This leaves oil and gas resource producers with only one option – accelerated development of oil and gas fields with low capital investment. This monograph is devoted to the development of oil and gas fields in a short period of time with a reduction in the volume of drilling operations and well quality by at least 50%. The developed technology of simultaneous split operation will give an impetus to volumetric production of hydrocarbons, accelerated field development and reduction of capital investments, as well as lead to the production of all recoverable and non-recoverable reserves from the subsoil. This monograph also delves into the technological aspects of operating wells in the Altyguyi gas condensate field. The scientific work examines the operational and technological aspects of hydrodynamic and thermohydrodynamic studies. To support this research, patents for invention No. 643 and 644, dated January 6, 2015, were obtained (application numbers 14/101317 and 15/101320). These patents cover the “Simultaneous method of separate and joint operation of several productive horizons by one chink and device for its realization” and the “Method of dual oil and gas production from one well in a multizone”. Based on the findings of the conducted analyses, studies, and calculations, the implementation of the intensification of the gas condensate field using the oil and gas DC method by one well is justified. This approach represents a first in global practice and aims to reduce capital investments and accelerate development.

Problems of oilfield and geophysical control over oil and gas fields development are for more than 10 years conventionally solved by using modern complex of nuclear methods. This complex includes pulse neutron logging (2INGK, 2INNK), carbon-oxygen logging (INGKS), spectral gamma-ray logging (SGK). Well logging equipment of the complex with merchandise mark TsSP is successfully being developed in OJSC SPE VNIIGIS in association with LLC SPE INGEO and is used for service performance in order to support oil and gas companies in Russia as well as CIS and far abroad countries. At the moment. the complex is competed by a new development such as 3INGKS, which realizes standard technology of 2INGK, neutron capture gamma-rays spectrocsopy for estimation of rock elemental composition, including weight content of hydrogen and chlorine, and also natural gamma-radiation spectrometry (U, Th, K). TzSP-2INGKS tool is 76 mm in diameter and can be used in boreholes of small diameter, including sidetracks and horizontal holes

The selection of well pattern system is not only the key content in the process of oilfield development, but also the core problem in the design of oilfield development. It is also the basis for the effective utilization of tight reservoir technology. Through scientific analysis of the geological structure and dynamic characteristics of Yang reservoir in H oilfield, the well pattern system can be reasonably optimized and the development of Chinese oilfield can be vigorous. Starting from the selection of well pattern system for oil and gas field development, this paper analyzes the optimization of well pattern system parameters of Fuyang reservoir in H oilfield.

To address the problems of complex composition, significant property variations, and difficult and costly harmless treatment of oil-contaminated sludge in oil and gas field development, its good compatibility with the formation is leveraged to formulate it with oilfield water into an oil–water profile control agent. This reduces the cost of harmless treatment and enables resource utilization of hazardous waste. The properties of oil-contaminated sludge were evaluated experimentally. Suspending agents and stabilizers were selected according to the oil–water profile control agent preparation process, the corresponding agents were prepared, and the system was experimentally tested. The experimental results show that the suspending agent carboxymethyl cellulose (CMC) and partially hydrolyzed polyacrylamide (HPAM), and the dispersant Dodecyl dimethyl betaine (BS-12) are used to prepare oil–water profile control agent based on the selected sulfonated mud oily sludge and ground system oily sludge. The optimal formulation of profile control agent is as follows: (1) 50% ground system oily sludge +50% oilfield produced water + 0.2% CMC + 1.0% BS-12; (2) 50% sulfonated mud system oily sludge +50% oilfield produced water + 0.1% HPAM + 1.0% BS-12. The preparation of a profile control agent from oily sludge is a viable low-cost resource treatment strategy for oily sludge, which is of great significance for the environmentally friendly treatment of oil and gas field development.

In development of mature oil fields using enhanced oil recovery (EOR) techniques, one of the challenges is to quantify remaining oil and to evaluate the potential gain of EOR in pilot studies. One of the proven technologies to estimate remaining amounts of oil is the single-well chemical tracer test (SWCTT). During such push-and-pull tests, oil/water partitioning ester partially hydrolyses to a non-partitioning water tracer. A time-lag in back-production time between the injected ester and the alcohol generated in-situ yields remaining oil saturation (ROS) through a simple relation. A similar time-lag technique is used in partitioning inter-well tracer tests (PITTs), where tracers are injected into injectors and sampled in producers. New and stable, oil-water partitioning tracers suitable for oil reservoir PITTs have been recently developed and field tested (SPE164059), allowing measurement of remaining oil saturation in inter-well regions. This paper reviews methodology to assess oil saturation in both near-well and inter-well regions of an oil reservoir, and highlights the differences and similarities of partitioning near-well and inter-well tracer tests that can be used to evaluate the potential gain from an EOR-operation. SWCTTs and PITTs target different scales of an oil field, as a SWCTT explores the near well zone, up to a few meters, and a PITT explore an inter-well region. In order to assess information on both these scales we propose a systematic procedure for oil saturation measurement, using partitioning tracers. The procedure involves use of PITTs and systematic residence time distribution (RTD) interpretation of tracer production curves to extract information about remaining oil saturation and the distribution of this saturation in an oil field. The procedure is validated using the tracer data recently reported by Viig et al. (SPE164059).

The Poseidon project aims at developing technology for subsea multiphase development of offshore oil and gas fields. This paper shows the potential of this technology through three synthetic North Sea field examples. The investment cost may be reduced by 10-40% using multiphase technology. Realizing this technology with an unmanned wellhead platform concept or a subsea (Poseidon) concept may give neglible cost differences. The main technical areas of concern are listed and some conclusions are drawn as to the future use of multiphase technology. THE POSEIDON PROJECT The Poseidon project was started in 1984 as a cooperation between Institut Francais du Petrole (IFP), Total and Statoil. The aim of the five year project is to develop the technology for subsea development of deepwater oil and gas fields. The concept, fig. 1 includes subsea wells, subsea multiphase pumps and long distance multiphase pipelines. In this project, IFP has developed a multiphase pump. An industrial prototype of this pump will be tested in a flow-loop, outside Lyon late 1988. Total has developed the subsea station and put main emphasis on full-scale test of an electric motor for the multiphase pump. This motor was tested in 150 meters of water outside the west coast of Norway in the autumn of 1987. Statoil's part of the work has been the pipeline system. A computer program for dynamic simulation of multiphase flow has been developed and used to study slugging phenomena and transient behaviour during start-up and shut-down of the pipeline. Moreover, numerous tests have been performed to study hydrate formation in flowing media as well as corrosion and erosion in the presence of oil, gas water and sand. Special consideration has been given to corrosion under sand beds and inhibitor efficiency in the roof of pipelines carrying mainly gas. Instrumentation for reservoir monitoring and control of pump inlet conditions have been studied. Finally, Statoil has headed the field concept studies in which also personnel from Total and IFP have taken part. This paper will present some of the conclusions from these studies. CONVENTIONAL OIL AND GAS FIELD DEVELOPMENTS Fig. 2 shows the functions included in a conventional field development. To arrive at new concepts it is necessary to consider if all these functions are necessary and where the accompanying equipment should be placed. Apart from the pipelines, the main part of the equipment and therefore also the investment and operating costs are connected to well control/manifolding, separation and pumping. Well control and manifolding are always necessary. The question is therefore whether the equipment should be placed on a platform or on the sea bottom. The equipment for separation and pumping is today always placed on a platform. Platforms for water depths of 70 to 500 meters, as in the Norwegian part of the North Sea, tends to be very large constructions, fig. 3. The Gullfaks C platform, which will be installed in 220 meters of water depths late this year, will cost in the order of 18 billion NOK.

As an important indicator for measuring the effectiveness and level of oil and gas field development, recovery rate has always been a focus in the research of oil and gas fields. Reservoirs of tight sandstone gas formations have significant characteristics of low porosity, high permeability, and high water content, which leads to greater difficulty in their development and makes it challenging to evaluate the recovery rate. Newtonian mechanics, as an important component of the mechanical system, is an innovative application of classical mechanics in the field of seepage mechanics when applied to the two-phase flow of gas and water. Firstly, starting from the perspective of mechanics analysis, we derive a steady-state model for gas–water two-phase infiltration and obtain the productivity equation based on this model. Then, according to the steady-state model, we establish a method to calculate the effective control radius of gas reservoirs under different production conditions and reservoir physical properties. Finally, using Matlab 2018a programming based on the productivity equation, we calculate the gas recovery under different conditions during constant pressure drop production and constant production rate production. The results indicate that the effective control radius of the reservoir decreases with an increase in the economic ultimate daily gas production, increases with an increase in production pressure difference, slightly decreases with an increase in startup pressure gradient, and correspondingly increases with an increase in microtube radius and quantity. Regardless of whether it is production with a fixed pressure drop or production with a fixed production rate, the gas recovery decreases as the production pressure drop and bottomhole abandonment pressure increase, but it increases as the proportion of the single-well control radius increases. In production with a fixed pressure drop, the gas recovery remains consistent across different reservoir quality indices. However, in production with a fixed production rate, the gas recovery initially increases rapidly and then gradually slows down as the reservoir quality index increases, and there is an obvious critical permeability (0.1 mD). The research findings are based on the mechanical analysis of porous media, delving into the laws governing fluid flow during infiltration. The derived infiltration model can be used to calculate the effective control radius and evaluate recovery rates, providing practical guidance for reservoir development.

Residual recoverable reserves of high-viscosity and heavy oils in the Republic of Kazakhstan amount to about 340 million tons. The main oil fields containing high-viscosity and heavy oil are Karazhanbas, Kenkiyak, Zhetybai, North Buzachi, Kenbai, etc. Improving the system for the development of high-viscosity oil fields and the selection of rational EOR is relevant for Kazakhstan, as this will increase the efficiency of their development. Given the high resource potential of such fields, it is necessary to develop and introduce new technologies in the development of high-viscous oil fields using enhanced oil recovery methods. To ensure high oil recovery factors, it is necessary to carefully select the EOR applicable to high-viscosity oil fields at an early stage of their development. This work is devoted to the problem of EOR selection in the development of high-viscosity oil fields. For the research polymer injection was selected. Evaluation of the efficiency of the proposed EOR was carried out based on the results of numerical experiments to displace high-viscosity oil with the creation of reservoir conditions. As a result, the aqueous polymer solution with the concentration of 0.05 % yielded 51% of oil recovery, whereas water injection recovered only 10% of oil. However, the interaction of the polymer with high-viscosity oil has not been deeply studied, which is relevant to the fields of Kazakhstan.

Background One of the key tasks of the Russian oil industry is the modernization of oilfield equipment for the development and operation of oil and gas fields. In this regard, the improvement of pumping systems on the basis of technology hydraulic piston long-stroke pumps is an important and urgent task. Aims and Objectives Justification of hydraulic piston pump applicability for deep depth oil production. Methods Theoretical studies Results The technological scheme of hydraulic piston long-stroke pump is designed and method of the hydraulic regime calculation is developed.

On-line monitoring technology for internal corrosion of CO2-EOR oil field