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Since reservoirs with permeability less than 10 mD are characterized by high injection difficulty, high-pressure drop loss, and low pore throat mobilization during the water drive process, CO2 is often used for development in actual production to reduce the injection difficulty and carbon emission simultaneously. However, microfractures are usually developed in low-permeability reservoirs, which further reduces the injection difficulty of the driving medium. At the same time, this makes the injected gas flow very fast, while the gas utilization rate is low, resulting in a low degree of recovery. This paper conducted a series of studies on the displacement effect of CO2-soluble foaming systems in low-permeability fractured reservoirs (the permeability of the core matrix is about 0.25 mD). For the two CO2-soluble blowing agents CG-1 and CG-2, the effects of the CO2 phase state, water content, and oil content on static foaming performance were first investigated; then, a more effective blowing agent was preferred for the replacement experiments according to the foaming results; and finally, the effects of the blowing agents on sealing and improving the recovery degree of a fully open fractured core were investigated at different injection rates and concentrations, and the injection parameters were optimized. The results show that CG-1 still has good foaming performance under low water volume and various oil contents and can be used in subsequent fractured core replacement experiments. After selecting the injection rate and concentration, the blowing agent can be used in subsequent fractured cores under injection conditions of 0.6 mL/min and 2.80%. In injection conditions, the foaming agent can achieve an 83.7% blocking rate and improve the extraction degree by 12.02%. The research content of this paper can provide data support for the application effect of a CO2-soluble blowing agent in a fractured core. [ABSTRACT FROM AUTHOR]

Shale oil is stored in nanoscale shale reservoirs. To explore enhanced recovery, it is essential to characterize the flow of hydrocarbons in nanopores. Molecular dynamics simulation is required for high-precision and high-cost experiments related to nanoscale pores. This technology is crucial for studying the kinetic characteristics of substances at the micro- and nanoscale and has become an important research method in the field of micro-mechanism research of shale oil extraction. This paper presents the principles and methods of molecular dynamics simulation technology, summarizes common molecular models and applicable force fields for simulating shale oil flow and enhanced recovery studies, and analyzes relevant physical parameters characterizing the distribution and kinetic properties of shale oil in nanopores. The physical parameters analyzed include interaction energy, density distribution, radial distribution function, mean-square displacement, and diffusion coefficient. This text describes how molecular dynamics simulation explains the mechanism of oil driving in CO2 injection technology and the factors that influence it. It also summarizes the advantages and disadvantages of molecular dynamics simulation in CO2 injection for enhanced recovery of shale oil. Furthermore, it presents the development trend of molecular dynamics simulation in shale reservoirs. The aim is to provide theoretical support for the development of unconventional oil and gas. [ABSTRACT FROM AUTHOR]

Enhancing oil recovery in shale is a critical technology for improving shale oil extraction efficiency. It is essential to develop a comprehensive set of physical simulation methods that are coherent and aligned with practical field operations. This paper establishes an integrated experimental approach, encompassing the entire Injecting-Stewing-Producing cycle, to simulate the actual Huff-n-Puff process accurately. Initially, the fracturing and flowback states are simulated by injecting an imbibition fluid, followed by a 48 h well-soaking process using CO2. The extraction is then carried out under various pressures. The microtransportation of crude oil across different pore sizes and the extent of extraction during shale oil Huff-n-Puff are investigated using Nuclear Magnetic Resonance technology. The results suggest that there was an initial increase in crude oil within pores smaller than 20 nm at the beginning of the Huff-n-Puff process. In Contrast, crude oil in pores larger than 200 nm was preferentially extracted, with oil in smaller pores (<200 nm) migrating to larger pores before extraction. After the initial Huff-n-Puff cycle, the extraction efficiency of the shale oil core reaches 29.55%, constituting 63.3% of the total extraction achieved over three Huff-n-Puff cycles. This study also identifies a critical pressure drop to 60% of the initial pressure as the optimal point for injection in subsequent Huff-n-Puff cycles. These experimental insights provide valuable guidance for the practical implementation of enhanced oil recovery techniques in shale formations. [ABSTRACT FROM AUTHOR]

Research into functional gels and chemicals and their applications represents a cutting-edge international field of study. For example, investigating how they can be applied in oil and gas drilling (and extraction engineering) and developing novel functional chemical materials for the oil field could provide innovative solutions and technological methods for oil and gas drilling and extraction operations. Through a literature analysis, this paper presents a review of the current research status and application scenarios of different types of functional gels and chemicals, both domestically and internationally. The classification and preparation principles of various functional materials are systematically outlined and the current applications of functional gels and chemicals in oil and gas drilling and extraction engineering are introduced. These applications include drilling and plugging, enhanced oil recovery, water plugging, and profile control. The formation mechanisms and application scenarios of different types of gels and chemicals are also analyzed and summarized, with a discussion of their prospects in oil and gas drilling and extraction engineering. We broaden the scope of functional gels and chemicals by exploring new application fields and promoting the development of different types of gels and chemicals in a more intelligent direction. [ABSTRACT FROM AUTHOR]

Since reservoirs with permeability less than 10 mD are characterized by high injection difficulty, high-pressure drop loss, and low pore throat mobilization during the water drive process, CO2 is often used for development in actual production to reduce the injection difficulty and carbon emission simultaneously. However, microfractures are usually developed in low-permeability reservoirs, which further reduces the injection difficulty of the driving medium. At the same time, this makes the injected gas flow very fast, while the gas utilization rate is low, resulting in a low degree of recovery. This paper conducted a series of studies on the displacement effect of CO2-soluble foaming systems in low-permeability fractured reservoirs (the permeability of the core matrix is about 0.25 mD). For the two CO2-soluble blowing agents CG-1 and CG-2, the effects of the CO2 phase state, water content, and oil content on static foaming performance were first investigated; then, a more effective blowing agent was preferred for the replacement experiments according to the foaming results; and finally, the effects of the blowing agents on sealing and improving the recovery degree of a fully open fractured core were investigated at different injection rates and concentrations, and the injection parameters were optimized. The results show that CG-1 still has good foaming performance under low water volume and various oil contents and can be used in subsequent fractured core replacement experiments. After selecting the injection rate and concentration, the blowing agent can be used in subsequent fractured cores under injection conditions of 0.6 mL/min and 2.80%. In injection conditions, the foaming agent can achieve an 83.7% blocking rate and improve the extraction degree by 12.02%. The research content of this paper can provide data support for the application effect of a CO2-soluble blowing agent in a fractured core.

With the growing global energy demand and limited production of conventional crude oil, the extraction of unconventional heavy and extra-heavy oil is receiving unprecedented attention. China is the fourth largest producer of heavy oil. High viscosity and complex formation environments increase the difficulty of exploiting heavy oil. To alleviate the economic cost and environmental pollution pressure brought by heavy oil production, China has achieved significant advancement in the innovation of heavy oil recovery, including accelerating the transformation of thermal technology to non-thermal technology and the use of new energy technology to achieve the goal of low-carbon economy and green environmental protection. Based on the background of heavy oil in China, this paper recharacterizes the high-viscosity mechanism of heavy oil. From different aspects, including basic principles, main characteristics, applicability, limitations, and challenges, this paper comprehensively reviews existing heavy oil recovery technologies, including thermal recovery, in-situ upgrading, cold recovery, and new energy technologies. Currently, in China, the main target of heavy oil recovery is achieving the "carbon peaking and carbon neutrality" goals, which can be described as low energy consumption, low emission, and low pollution. To facilitate the low-carbon transition in the extraction of heavy/extra-heavy oil and attain environmental sustainability goals, it is essential to increase the proportion of non-thermal factors in thermal recovery technologies, develop efficient in-situ catalysts, adopt clean cold extraction techniques, and advance the development of new energy technologies. [ABSTRACT FROM AUTHOR]

Low salinity Waterflooding (LSWF) is a proven EOR technique which has emerged in the last few decades. In this, the salinity of the injected water is reduced. Studies have unveiled that the LSWF can improve about 5–38% of oil recovery. This work aims to study the effectiveness of LSWF by modeling Sea waterflooding (SWF) and LSWF using a commercial reservoir simulator and justifying the proposed mechanisms responsible for the incremental oil recovery due to LSWF. A critical parametric study has been undertaken, which led us to conclude that LSWF is a cost-effective, and environment-friendly method that results in additional oil recovery for sandstone reservoirs. [ABSTRACT FROM AUTHOR]

This retrospective study aimed to examine the safety and clinical outcomes of enhanced recovery after single-site robotic staging surgery in patients with endometrial cancer. Data were collected from Seoul St. Mary's Hospital's electronic medical records between July 2017 and August 2021. All the included endometrial cancer patients underwent single-site robotic staging surgery followed by enhanced recovery after surgery based on the guidelines for enhanced recovery after surgery society recommendations. The factors assessed were survival outcomes, complications and postoperative adjuvant therapy. Of the 60 patients included in this study, four (6.7%) experienced grade III postoperative complications within 30 days after surgery. Additionally, there were five cases (8.3%) that required a visit to the emergency room and two cases (3.3%) that necessitated readmission. Seventeen patients (28.3%) received postoperative adjuvant therapy, with treatment initiated 8 weeks after staging surgery in 14 patients (23.3%) and over 8 weeks in three patients (5.0%). The follow-up duration averaged 32.0 months (range, 3 to 60 months). No mortality was recorded during the follow-up period after staging surgery. The recurrence rate was 5.0% (n = 3), and the 3- year progression-free survival rate for the endometrioid type was 94.3%. These findings suggest that enhanced recovery after single-site robotic staging surgery is feasible for patients with endometrial cancer, yielding similar clinical outcomes and manageable complications without extending the time to adjuvant therapy initiation. However, further studies are necessary to investigate the long-term survival outcomes associated with enhanced recovery after surgery application. [ABSTRACT FROM AUTHOR]

The present review discusses restrictive perioperative fluid protocols within enhanced recovery after surgery (ERAS) pathways. Standardized definitions of a restrictive or liberal fluid regimen are lacking since they depend on conflicting evidence, institutional protocols, and personal preferences. Challenges related to restrictive fluid protocols are related to proper patient selection within standardized ERAS protocols. On the other hand, invasive goal-directed fluid therapy (GDFT) is reserved for more challenging disease presentations and polymorbid and frail patients. While the perfusion rate (mL/kg/h) appears less predictive for postoperative outcomes, the authors identified critical thresholds related to total intravenous fluids and weight gain. These thresholds are discussed within the available evidence. The authors aim to introduce their institutional approach to standardized practice. [ABSTRACT FROM AUTHOR]

Craniotomy, an essential neurosurgical operation, poses distinct difficulties in the realm of post‐operative care, specifically with regard to the management of wounds. Efficient wound management is critical in order to optimize the surgical outcomes, reduce complications and facilitate a speedier recovery. The purpose of this comprehensive review was to assess contemporary wound management approaches as they pertain to improved recovery following craniotomy. This was achieved by contrasting conventional methods with more recent and innovative techniques and analysing the effects of these approaches on patient recovery and surgical results. An exhaustive literature search was undertaken, comprising narrative reviews, clinical studies, peer‐reviewed articles and expert opinions. The emphasis was on the evolution of wound management strategies and techniques utilized after cranial section, as well as their contributions to patient recovery. The analysis reveals that while conventional wound management methods, including suturing and antiseptics, continue to be essential, innovative strategies such as negative pressure wound therapy, skin adhesives and advanced pain management protocols are becoming increasingly recognized. It has been demonstrated that these novel approaches improve recovery by decreasing the incidence of infections, enhancing patient comfort and producing superior cosmetic results. Nevertheless, obstacles continue to endure, including patient‐specific variables, technological and financial considerations and the enduring consequences of recovery. Thus the treatment of wounds during craniotomy recuperation necessitates an integrated strategy that incorporates conventional techniques alongside contemporary advancements. Progress in this domain necessitates the customization of approaches to suit the unique requirements of each patient, the resolution of identified obstacles and an emphasis on ongoing investigation and interdisciplinary cooperation. The ever‐changing terrain of wound management approaches underscores the ever‐changing character of neurosurgical treatment and the continuous endeavour to enhance patient results following cranial resection. [ABSTRACT FROM AUTHOR]

Shale oil is stored in nanoscale shale reservoirs. To explore enhanced recovery, it is essential to characterize the flow of hydrocarbons in nanopores. Molecular dynamics simulation is required for high-precision and high-cost experiments related to nanoscale pores. This technology is crucial for studying the kinetic characteristics of substances at the micro- and nanoscale and has become an important research method in the field of micro-mechanism research of shale oil extraction. This paper presents the principles and methods of molecular dynamics simulation technology, summarizes common molecular models and applicable force fields for simulating shale oil flow and enhanced recovery studies, and analyzes relevant physical parameters characterizing the distribution and kinetic properties of shale oil in nanopores. The physical parameters analyzed include interaction energy, density distribution, radial distribution function, mean-square displacement, and diffusion coefficient. This text describes how molecular dynamics simulation explains the mechanism of oil driving in CO2 injection technology and the factors that influence it. It also summarizes the advantages and disadvantages of molecular dynamics simulation in CO2 injection for enhanced recovery of shale oil. Furthermore, it presents the development trend of molecular dynamics simulation in shale reservoirs. The aim is to provide theoretical support for the development of unconventional oil and gas.

Enhancing oil recovery in shale is a critical technology for improving shale oil extraction efficiency. It is essential to develop a comprehensive set of physical simulation methods that are coherent and aligned with practical field operations. This paper establishes an integrated experimental approach, encompassing the entire Injecting-Stewing-Producing cycle, to simulate the actual Huff-n-Puff process accurately. Initially, the fracturing and flowback states are simulated by injecting an imbibition fluid, followed by a 48 h well-soaking process using CO2. The extraction is then carried out under various pressures. The microtransportation of crude oil across different pore sizes and the extent of extraction during shale oil Huff-n-Puff are investigated using Nuclear Magnetic Resonance technology. The results suggest that there was an initial increase in crude oil within pores smaller than 20 nm at the beginning of the Huff-n-Puff process. In Contrast, crude oil in pores larger than 200 nm was preferentially extracted, with oil in smaller pores (

Research into functional gels and chemicals and their applications represents a cutting-edge international field of study. For example, investigating how they can be applied in oil and gas drilling (and extraction engineering) and developing novel functional chemical materials for the oil field could provide innovative solutions and technological methods for oil and gas drilling and extraction operations. Through a literature analysis, this paper presents a review of the current research status and application scenarios of different types of functional gels and chemicals, both domestically and internationally. The classification and preparation principles of various functional materials are systematically outlined and the current applications of functional gels and chemicals in oil and gas drilling and extraction engineering are introduced. These applications include drilling and plugging, enhanced oil recovery, water plugging, and profile control. The formation mechanisms and application scenarios of different types of gels and chemicals are also analyzed and summarized, with a discussion of their prospects in oil and gas drilling and extraction engineering. We broaden the scope of functional gels and chemicals by exploring new application fields and promoting the development of different types of gels and chemicals in a more intelligent direction.