Development Of Gas Resources Research Articles

Tight Gas Potential Status, Obstacles and the Way Forward in Meeting Future Energy Needs of Pakistan

Production from unconventional tight gas resources plays significant role in energy market. It is commonly held that the tight gas has gained considerable importance in meeting energy needs and is widely developed across the world. It is also worth noting that several countries are engaged in pursuing the tight gas resources development to meet energy challenges. However, the copious concerns have emerged to technical and economic development of tight gas potential. Hence, it is essential to accurately assess the resources and to address the key technical issues and economic feasibilities that will support in mitigating the risk and to increase the investment opportunities. This paper provides a systematic review about current status, field development best strategies; in addition, the paper also addresses the obstacles and issues for development of tight gas potential in Pakistan. Although, the efforts made by the Exploration and Production (E&P) firms operating in Pakistan are not very encouraging for tight gas resources development. Hence; this requires further improvements and accurate assessments to develop tight gas resources effectively. Thus, for accurate assessment of tight gas potential, various imperative approaches, ideas, considerations, several challenges and the best strategies for field development are highlighted that offers significant improvement in materializing the future trends in tight gas potential development. The paper will be a kind of helpful tool for the policy makers, potential investors and industry professionals working in Pakistan’s E&P industry.

Rotation system as the basic source of workforce for the development of oil and gas resources of the arctic polar regions

The purpose of the study is to analyze the use of the rotation system in the development of oil and gas resources in the Arctic region using the example of its polar municipal regions. Relevance. The depletion of the main hydrocarbon reserves in the previously developed areas of the Yamalo-Nenets Autonomous Okrug led to a shift in industrial development to new sparsely populated areas located beyond the Arctic Circle characterized by extreme natural conditions and with significant potential of natural resources that are attractive to investors. The absence of local labor resources in the regions of development and the low qualification level of local labor resources demanded that they be attracted from other regions using a rotation system. The research methodology consists in the generalization and analysis of information regarding the application of the rotation system in the studied areas. The main methods were statistical, retrospective analysis, comparison, groupings, averaging, and analogy. The information base of this study is data from regional and municipal statistics. Results. In the course of the study, the expediency of using a rotation system as the main method was confirmed, which has no alternative, the method of attracting labor force in the development of oil and gas resources in extreme polar regions. The need for shift personnel for the basic and infrastructure industries at various stages of the development of mineral deposits from the initial (pioneer) stage to their permanent operation has been identified. The characteristic of the natural-resource and socio-economic potential of the attractive Yamal region in terms of investment is given. The special place and its role in the economy of the region are noted, medium-term development prospects are considered. Conclusions. The rotation system of attracting workers to the development of oil and gas resources is generally recognized and used both in domestic and foreign practice. The increase in the share of rotational personnel in the total number of employed in the polar regions is due to their low population density, the lack of local skilled labor and the extreme nature of the natural environment, which prevents the adaptation of the newcomer population to climatic conditions and the creation of a permanent contingent of labor resources.

Preparation and Performance Evaluation of an Environmentally Friendly Lubricant for Water-based Drilling fluid

With the increasing difficulty of exploration and development of oil and gas resources, the problems of high friction torque in long horizontal well section and high temperature in deep well are increasingly prominent, which put forward higher technical requirements for the lubricity, temperature resistance and environmental protection of drilling fluid lubricant. Traditional drilling fluid lubricants are difficult to meet the above technical requirements. Based on the optimization of modified vegetable oil, extreme pressure agent, surfactant, antioxidant and preparation conditions, an environmentally friendly drilling fluid lubricant SDGL-2 was developed. The evaluation results show that the lubricant SDGL-2 has fluorescence grade of 1~2, temperature resistance of 160 °C, good biodegradability and no toxicity. Its lubricity is better than that of common drilling fluid lubricants, and it is compatible with several common drilling fluids.

Geological structure and paleogeographic zoning of the Khadum formation in Pre‑Caucasus

Unconventional oil and gas resource development and exploration is the one of the most prospective concept in petroleum geology. High carbon Khadum facies are investigated as unconventional resources in the Precaucas basin and contain gas, gas condensate and oil accumulations. Oligocene and Lower Miocene structure, prospectivity and fields distribution are the one of the most relevant subjects nowadays. This study is focused on the main stages Late Eocene and Early Oligocene deposits formation and the paleogeography of the Khadum formation in the Precaucas oil and gas basin. The new prospective zones are developed in Khadum formation based on the complex analysis of seismic, paleogeography and lithofacies analysis.

Investigation of casing deformation characteristics under cycling loads and the effect on casing strength based on full-scale equipment

Production casing deformation has hindered the safe and economic development of shale gas resources, especially in Weiyuan-Changning Shale Gas field, China. In terms of current literatures, this problem should be attributed to the casing failure induced by varying high loads during the multi-fracturing process. However, the characteristics of casing deformation under cycling loads have hardly been investigated in previous work. In order to realize the casing deformation mechanism during multi-fracturing, the casing deformation real-time monitoring system is improved, based on full-scale casing-cement sheath-formation system (CCFS) combination device. Further, the deformation testing experiments of P110 casing under cycling inner pressure loads, for four conditions (1#-standard condition, 2#-higher inner pressure, 3#-thinner casing, 4#-thicker cement sheath), are carried out … Besides, the reliability of experiment approach is verified, by the consistency of effective circumference strain values in the loading process of first cycle between calculated by elastic theory and determined in this paper. Further, the casing strength under cycling loads is analyzed, to evaluate the casing failure in shale gas well. Results illustrate that the casing under cycling loads are available to generate residual strain, which are reliable to reach 0.035%, 0.104%, 0.042% and 0.027%, respectively, based on above mentioned four testing parameters under 16 cycles. The higher cycling inner pressure significantly increases the residual strain of casing, which is harmful for the casing protection. Increasing the thickness of casing and cement sheath is beneficial to reduce the residual strain of casing. The casing collapsing strength is linearly lowered with cycling number, due to the growing unrecovered strain of casing during multi-fracturing. It precisely explains the phenomenon that casing deformation frequently occurs in the last few fracturing stages of shale gas wells. The casing strength lines from experiment results demonstrate higher accuracy than API (American Petroleum Institute) standard, in evaluating the casing failure of field cases. This work will provide a new criterion for the parameters designs of casing and fracturing in shale gas wells, to reduce the risk of casing deformation during multi-fracturing. • The measurement of casing strain under cycling loads is achieved. • Casing under cycling loads are available to generate residual strain rather than perfect elastic strain. • The equations predicting residual strain of casing are raised by fitting experiment data. • Casing strength lines determined in this paper demonstrate higher accuracy than API standard in shale gas wells.

Analysis of Environmental Impact Assessment Indexes of Oil and Gas Resources

Environmental impact assessment is one of the important tasks that oil companies need to complete in the exploration and development of oil and gas resources. In order to explore the related issues of the environmental impact assessment of oil and gas resources exploration, based on the analytic hierarchy process, the index weights of the environmental impact of oil and gas resources exploration and development are determined, and triangular fuzzy is used. Calculate the environmental impact index value of onshore oil and gas resource exploration and development with the number of language variables, and finally conduct an evaluation analysis through a comprehensive evaluation model, which is conducive to identifying and evaluating the environmental impact of oil and gas resources.

The overall process of high-deck float-over for the large platform in paralic zones

As the demand for oil and gas resources continues to grow, the development of oil and gas resources in paralic zones is also increasing. Because the water depth is very shallow in paralic zones, large construction equipment cannot enter the construction area, so the offshore installation of large platforms is facing a great challenge. The float-over installation method has the advantages of large lifting capacity, short operation period, and low construction cost. At the same time, it can effectively reduce the amount of dredging work and is more suitable for the offshore installation of large platforms in paralic zones. In this paper, the installation process and key technologies of hi-deck float-over for the large platform in paralic zones are emphatically introduced. The key technologies include the barge motion response analysis technology, the barge ballast adjustment technology, the positioning and buffering technology and motion monitoring technology, etc.

MODELING THE PENETRATION DISTANCE OF POWER-LAW CEMENTING FLUID TRANSPORT IN DEEP-WATER WEAKLY CONSOLIDATED FORMATION

During the development of deep-water oil and gas resources, severe engineering problems or even marine geological hazards might be induced by the complex geological characteristics of deep-water weakly consolidated (DWC) formation. To solve these problems, the power-law cementing fluid was used to solidify the DWC formation during the well-cementing operation. However, the transportation process of cementing fluid in DWC formation is still unclear. To guide the solidification operation of DWC formation, a mathematical model for predicting the penetration distance of cementing fluid in DWC formation was proposed based on the generalized Darcy’s law and fractal theory. All the parameters in this model have clear physical meaning and no empirical parameter is involved. The numerical and experimental validation results show that the proposed model calculated penetration distance agrees well with both simulated and experimental results. The model capacity relates to the penetration pressure, the viscosity of cementing fluid, the permeability of formation, the effective radius of the flow path and the fractal dimension of formation. The maximum error of this model is less than 20%, which indicates that the mathematical model is reliable.

Distortion model design of flexible marine riser

With the development of deep-sea oil and gas resources, the aspect ratio of deep-sea flexible riser has reached the order of 102–103, which makes the experimental model of the equal scale of deep-sea flexible risers challenging to achieve under typical experimental conditions. Alternatively, the non-scale experiment is sometimes used. However, the dynamic response of the prototype may not be exactly modeled. To solve the problem, this paper expands the distortion similarity method to consider the pretension and designs a distortion model of the deep-sea flexible riser based on the improved distortion similarity method. Applying the governing equation and dimensional analysis method to analyze the prototype and experimental model, the design method of the distortion model is obtained. In the numerical analysis, the design of the distortion model of a top tensioned riser (TTR) is carried out, and the selection criteria and range of the aspect ratio are proposed. The three parts of the natural frequency similarity, the pretension non-satisfaction similarity, and the error analysis are studied. This analytical study indicates that the transverse direction of the distortion model satisfies the similarity of the dynamics, and the longitudinal direction satisfies the static similarity. The selection of the aspect ratio of the distortion model should satisfy three factors.

Oil and gas development does not reduce duck pair abundance in the Prairie Pothole Region

AbstractConservation partners are concerned that oil and gas development in the Prairie Pothole Region may reduce the abundance of breeding duck pairs using associated wetland habitat. We conducted wetland-based surveys for breeding pairs of 5 species of dabbling ducks in the Bakken oil field during 2015–2017 across a gradient of oil and gas development intensity to test the hypothesis that the abundance of breeding duck pairs on survey wetlands would decrease as the development of oil and gas resources increased. We included covariates traditionally used to predict breeding duck pairs (i.e. wetland size and class) and a spatiotemporal index of disturbance when developing zero-inflated Poisson models relating pair abundance to environmental predictors. Similar to past analyses, pair abundance was strongly associated with wetland size. Our results were mixed and suggested that the abundance of early and late nesting species was positively and negatively related, respectively, to an index of disturbance that was largely driven by oil and gas development. Regardless of the direction of the relationship, effect sizes were small and not considered biologically significant. Our findings indicate that in our study area, strategies to conserve wetland resources for breeding duck pairs should not deviate from previous prioritization metrics within the range of oil and gas development we observed. We believe that our findings may have implications to similar landscapes within the Bakken.

Fracturing technology with carbon dioxide: A review

As unconventional oil and gas have increasingly gained considerable attention, the application of water-free fracturing technology represented by carbon dioxide (CO 2 ) fracturing technology in unconventional oil and gas resources development has broad prospects. The CO 2 fracturing technology has several advantages, such as low damage and easy flowback. It is especially suitable for complex rock strata exhibiting low pressure, low permeability, and strong water sensitivity. Moreover, this technology positively affects the reservoir with low water content and experiencing serious pollution. In this paper, the related literature of the different CO 2 fracturing technologies from the aspects of technical principle and technological process, technical characteristics, fracturing fluid system, and field application is analyzed, the fracture initiation and propagation are summarized as well. The results indicate that CO 2 fracturing can stimulate unconventional reservoirs more effectively than the conventional hydraulic fracturing, exhibits high technical feasibility, and can be applied in the reservoir stimulation and reconstruction in the future. In this paper, how to further improve the viscosity of fracturing fluid, enhance the sand-carrying capacity of fracturing fluid, and reduce the pipeline friction is determined. • The latest advancements in CO 2 fracturing technology are reviewed. • The phase change process in CO 2 fracturing is clearly introduced. • CO 2 fracturing is a technically feasible means of reducing CO 2 . • CO 2 fracturing has broad application prospects in unconventional reservoirs.

A new method for wellbore stability evaluation based on fractured carbonate reservoir rock breaking degree

Borehole wall collapse is rare in the drilling of carbonate rock formations. However, several wells in the Maantang–Leikoupo carbonate formation have collapsed and released blocks to varying degrees, which have caused sticking and hindered efficient development of oil and gas resources. Thus, through the study of macroscopic and microscopic characteristics of carbonate rocks in this area, it is concluded that the fractures in this area are developed. In order to facilitate the analysis of formation fracture development, the concept of formation integrity coefficient which is commonly used in rock engineering was introduced. Firstly, the feasibility of using the formation integrity coefficient to characterize the degree of rock fragmentation was verified by the laboratory acoustic experiment. Finally, the empirical formulas were proposed regarding the formation integrity coefficient and the cohesion of carbonate rocks in this area by combining the laboratory mechanical experiment and acoustic experiment, and a calculation model for the collapse density considering formation integrity was established. Results provide guidance for research on carbonate wellbore stability, especially for fractured carbonate strata.

Principal features of the continental shelf oil and gas resources development

According to forecast estimates, the depletion of continental oil and gas fields of the Russian Federation is 30 - 50%, and the fields of the continental shelf are less than 1%. Therefore, the main volumes of growth of reserves, oil and gas production in the fuel and energy complex system should be planned at the expense of resources and reserves of the continental shelf. The article considers the principal features of development of oil and gas fields of the continental shelf and criteria determining types of offshore oil and gas fisheries.

The Economic and Environmental Impact of Marine Engineering on the Development of Offshore Oil and Gas Resources

The Economic and Environmental Impact of Marine Engineering on the Development of Offshore Oil and Gas Resources

Comparative analysis of country approaches towards the development of oil and gas resources of the Arctic shelf and identification of opportunities of foreign experience application in Russia

For the Russian economy, which is so heavily dependent on energy production, the issue of Arctic development is very important. Practice shows that some countries are successfully producing oil and gas in the northern seas. However, only one field has been put into industrial operation on the Arctic continental shelf in Russia at the moment. Therefore, the analysis of approaches to the development of the Arctic shelf of other countries and the study of foreign experience of state stimulation of investments in the development of Arctic resources are now extremely relevant. At the same time, Norway is most interested, so successfully developing its hydrocarbon-based economy. In addition, Norway has access to the same Arctic sea as Russia and is actively engaged in industrial production in it.

Big data intelligent platform and application analysis for oil and gas resource development

With the rapid improvement of exploration and monitoring technologies, the oil and gas industry has accumulated a large amount of data in the fields of seismic exploration, logging, production, and development. How to transform the huge “data resources” into “data assets” and fully utilize data and tap their real value to better serve society is a main concern in the oil and gas industry today. Therefore, the oil industry needs to complete the industrial upgrading of “Smart Oilfield” through digital and intelligent transformation. In recent years, the rise of big data technology and artificial intelligence have allowed international oil companies and oil service giants to accelerate the construction of digital and intelligent oil fields. The overall framework of the big data intelligent platform of oil and gas resources should be based on data resources with big data platform computing power as the support and artificial intelligence algorithms as the core. To meet the production needs of the oil and gas industry, it is of great urgency to build an oil and gas data resource pool that integrates exploration, development, and production data. The data quality can be improved via data cleaning and fusion. Physical simulations, data mining, and other approaches should be combined to achieve the modularization of service functions. Additionally, the goals of intelligent monitoring, early warning, and display on multi-dimensional platforms such as PC, control screen, and mobile apps can also be achieved. The analysis of artificial intelligence methods such as deep learning in the context of the oil and gas industry shows that these methods have good application prospects. In the future, oil companies should work together with scientific research institutes to tap the huge potential of oil industry data, achieve cost reduction and efficiency increase, and build a new smart oil and gas industrial ecosystem to complete industrial upgrading.

Development of a novel temperature-resistant and salt-resistant double-cationic surfactant with “super thick hydration layer” for clean fracturing fluid

In recent years, cationic surfactants have received extensive attention in cleaning fracturing fluid thickeners due to various unique properties. At the same time, the development of temperature-resistant and salt-resistant clean fracturing fluid is the key to deep well oil and gas resource development. In this study, the rigid-soft combined strategy is adopted for molecular structure designs. N,N-dimethylcyclohexylamine and epichlorohydrin are used as the initial reactants; after the ring-opening reaction occurs, they are quaternized with erucamide propyl dimethyl ammonium to synthesize a novel double-cation viscoelastic surfactant, SY–JS. With double-cationic charges on the head group, water molecules are selectively adsorbed around the cation lattice to increase the hydration layer, and thus, salt tolerance is improved. Cyclohexane with a rigid structure improves temperature resistance. The ultra-long unsaturated hydrophobic tail imparts excellent heat tolerance and dissolubility to the designed viscoelastic surfactant. The clean fracturing fluid prepared by 3 wt% SY–JS with 130,000 ppm NaCl or KCl performs well under a shear rate of 170 s−1 at 140 °C, and the apparent viscosity remains above 30 mPa s−1 after 120 min.. Additionally, the results show that single-tail surfactants exhibit excellent performance at approximately 140 °C. Afterward, the brine produced from Rumaila and Jiyuan oil fields is used to prepare brine-based clean fracturing fluids, and evaluations, including proppant suspension, gel breaking, and permeability damage, were conducted. The results show that the brine-based clean fracturing fluid completely meets the requirements of hydraulic fracturing industrial application.

Mudstone diagenesis: Research advances and prospects

Driven by the shale oil and gas revolution，important advances have been made in mudstone diagenesis， which is a frontier in sedimentology and petroleum geology. Mudstone diagenesis of not only controls the generation and migration of oil and gas， but also has important influence on the composition， microstructure， reservoir physical and mechanical properties. The research status and prospects of the study were documented. At present， the research advances of mudstone diagenesis is mainly reflected in 4 aspects： （1）diagenetic evolution of inorganic minerals； （2）diagenetic evolution of organic matter and the development of organic matter-hosted pores； （3）driving mechanism and physical response of mudstone diagenesis； （4）effects of diagenesis on mechanical properties of mudstone. The study of mudstone diagenesis will continue to complement and improve the basin diagenesis system， and provide theoretical support for the exploration and development of unconventional oil and gas resources. The study of mudstone diagenesis system at different scales under the control of multi-field coupling indicates a profound and extensive development prospect.

Preparation and characterization of controlled‐release microencapsulated acids for deep acidizing of carbonate reservoirs

AbstractBased on the deficiency of traditional acidification or acid pressure technology in the development of carbonate oil and gas resources, a microcapsule which wraps hydrochloric acid and can be released through temperature control was prepared by using microcapsule technology. The microcapsules were prepared with polyurethane prepolymer (PUA) and 1,6‐hexadiol diacrylate (HDDA) polymer as wall material and hydrochloric acid as core material by two emulsification and photocatalysis methods. Its parcel rate is 61.9%. Fourier transform infrared spectroscopy characterization confirmed the successful photopolymerization of PUA prepolymer and HDDA in a strong acid environment. The microscopic morphology analysis of electron microscope showed that the microcapsule was regular and uniform spherical with smooth and dense surface. The particle size analysis showed that the microcapsules were mainly distributed between 40 and 300 μm, and the average particle size was 114.02 μm.The glass temperature of microcapsule wall material was 97°C by DSC method. The release rate of microcapsules was accelerated with the increase of release temperature. The cumulative release rate of acid solution of microcapsules for 3 h reached 28.4%, and the final release rate of microcapsules for 12 h reached 90.7% under 100°C. In addition, the release of microcapsules is less affected by the formation salinity. At 90°C, the maximum release rate of 7.5 g/L CaCL2 was 49.1%, lower than that of 59.4% in pure water, showing the good salt resistance of the wall materials of microcapsules.

The influence of compound heating power distribution on heat transfer

With the continuous deepening of oil and gas resource development, the number of large cargo tankers is increasing rapidly, and the tankers need to heat and keep the cargo oil in the tanks during navigation. However, the traditional steam coil heating method has many problems, such as low thermal efficiency and large total fuel consumption, which will cause energy waste and increasing oil tanker transportation costs. Microwave heating technology has the characteristics of fast, uniform and efficient heating, and is widely used in petroleum extraction and viscosity reduction of heavy oil. This paper proposes a new heating method of steam-microwave composite heating to heat the cargo in the tanker cabin. Taking a VLCC side cabin as a prototype, a three-dimensional numerical scale model is established through COMSOL software to study the influence of thermal efficiency under different power distribution between steam and microwave. The research results show that when the total power is constant, the smaller the proportion of microwave power, the more beneficial it is to improve the heat transfer efficiency in oil heating. This research has important guiding significance for improving oil heating efficiency and saving energy consumption.