Abstract Supercritical CO2 (SC-CO2) fluid has the properties of low viscosity and high diffusion capacity near gas higher density liquid, so it showed great vitality at beginning its use in drilling technology end last century. This article analyzes thermophysical SC-CO2 fluid, shale reservoir are analyzed different aspects formation, while characteristics development summarized also. Combining exploitation, feasibility exploitation with is demonstrated detail. Meanwhile, technical economic...

Internal photoemission is a prominent branch of the photoelectric effect and has emerged as viable method for detecting photons with energies below semiconductor bandgap. This breakthrough played significant role in accelerating development infrared imaging one chip state-of-the-art silicon techniques. However, performance these Schottky detectors currently hindered by limit internal photoemission; specifically, low barrier height inevitable detection low-energy photons. Herein, distinct...

The CO2-responsive Pickering emulsions employed have garnered considerable attention across enhanced oil recovery agents, delivery of crude, and oilfield-produced fluid treatment. This study focuses on the design an innovative type Janus nanoparticle (JNP) its application in construction CO2 stimuli-responsive emulsions. emulsion stabilized by JNPs demonstrates swift phase separation subsequent to injection CO2. Furthermore, mechanism CO2-stimulated responsiveness enabled was proposed. Based...

Inadequate strength and stability of active crude oil emulsions stabilized by conventional surfactants always lead to a limited plugging rate agents. Thus, address this issue, the synthesis amphiphilic Janus nanosheets was effectively carried out for enhancing system performances subsequently characterized. Based on outcomes orthogonal tests, an assessment conducted nanosheet surfactant formulations optimize enhancement emulsion properties. The experimental demonstration complex has revealed...

Summary On the basis of analysis jet-modulating mechanism, a novel tool—a hydraulic-pulsed cavitating-jet generator (HPCJG)— is designed to further improve rate penetration (ROP). The HPCJG combines advantages pulsed jet and cavitating jet. When drilling fluid flows through this tool, will be modulated by application impellers entering into self-resonant chamber. During process, formed at outlet bit nozzle. Because pulsation, erosion, local negative-pressure effect, cleaning efficiency...

To construct the in-situ emulsification and viscosification system that is suitable for low permeability oil reservoirs characterized by high-temperature high-salt, amphiphilic Janus SiO2 nanoparticles Tween 60/Imidazoline oleate surfactant were combined. The mechanism of was elucidated from two aspects: dynamic adsorption phase conversion surfactant, unique bridge structure nanoparticle stabilized emulsion. successful synthesis with varying degrees hydrophilicity hydrophobicity achieved...

Abstract How to improve drilling rate in deep wells has been a hot subject. Based on modulating pulse jet and cavitating jet, new tool is designed which couples advantages of both jet. When fluid flows through the during process, modulated cavitate. Thus, formed at outlet bit nozzle. Because pulsation, erosion local negative pressure affect bottomhole rock. Cleaning breaking enhanced penetration speed improved. Oil field tests five show good applicability types, formation, densities, flow...

Abstract Lead sulfide (PbS), a classical narrow‐bandgap material, has manifested itself as reliable choice for short‐wave infrared (SWIR) detection with high sensitivity. The primary efforts of optimizing PbS‐based photodetectors rely on discovering new low‐dimensional morphology and designing delicate device architecture, which may raise problems in the synergistic improvement response speed, sensitivity, region. Herein, graphene‐PbS nanocuboids‐graphene vertical photodetector is reported,...

Abstract An economic production scheme for gas shale demands a better understanding of flow behavior and proper reservoir simulator. The complex fracture network multi-scale channel intensify the complexity behavior. This paper integrated an improved shale-gas transport model with extended finite element method (XFEM) to characterize main mechanisms discrete network. was viewed as dual permeability porous media fractures. fractures are not required be meshed, which can placed anywhere given...

Abstract Supercritical carbon dioxide (SC-CO2) as a new drilling fluid had developed rapidly from the end of last century. The use SC-CO2 can not only obtain low threshold pressure, high rate penetration, and excellent hole cleaning capabilities, but also enhance oil recovery protect reservoir effectively in low-permeability reservoir. Thermodynamic thermophysical properties were studied. Meanwhile, present situation, advantages, development direction technology analyzed. results indicated...

Position-sensitive detectors (PSDs) are of great significance to optical communication, automatic alignment, and dislocation detection domains, by precisely obtaining the position information infrared light spots which invisible human eyes. Herein, a kind PSD based on graphene/germanium (Ge) heterojunction architecture is proposed demonstrated, exhibits amplified signals unitizing charge injection effect. Driven graphene/Ge heterojunction, large number photogenerated carriers diffuse from...

Abstract This article presents the experiment process and results of abrasive water jet perforation. was conducted in Kalamayi, China, Xinjiang Oilfield October 2004. Referring to explosive perforation experiment, we made two cement cylinder samples with a diameter 2.4 m, 1.2 m high, putting 139.7 mm (5-1/2″) 177.8 (7″) casing sub them, respectively. The cylinders were buried underground. During changed following parameters: blasting time, nozzle diameter, property. After opened found that,...

Abstract Continuing high prices for oil and gas stimulate new technologies improve the production of low permeability reservoirs. Hydrajet-fracturing with coiled tubing, a unique technology low-permeability horizontal vertical wells, uses fluids under pressure to initiate accurately place hydraulic fracture without packer, saving operating time lowering risk. The mechanisms hydrajet-perforation hydrajet-fracture initiation are studied in this article. Frictions one kind fracturing fluid...

Abstract Underground gas storages (UGS) have been built around the world. Several UGS are transformed from depleted reservoirs near Beijing. wells always endure complex working load, having high possibility of failure. Besides, repetitive injection/production circles induce dramatic periodic changes pore pressure and wellbore stresses, meaning formation breakdown can be triggered. On account these facts, it remains necessary to verify whether we produce or inject as planned in UGS. A...

Abstract This article presents the boosting mechanism in cavity during a hydrajet fracturing process. It is found that there are two kinds of pressures enhancing value within cavity. One impact pressure by jetted fluid from nozzle, and other back-pressure hole casing. A numerical simulation method was utilized to evaluate effects combined with experiment results. Distribution obtained. The results show higher than wellbore. will be increased nozzle drop diameter rising. plays an important...

Abstract Supercritical carbon dioxide (SC-CO2) drilling technology is a new type of technology, which has developed rapidly since the end last century. With lower jet erosion threshold pressure, higher speed, and excellent hole cleaning capabilities, SC-CO2 receives much attention. However, for fluid, density, viscosity, heat capacity, Joule-Thomson coefficient, so on are more sensitive to changes wellbore temperature at same time change parameters will react they should be widely...

Abstract This article presents a new technology of abrasive water jet perforation assisting fracturing on Well Zheng 408-8, Bin Nan Production Plant, Shengli Oilfield. First, the balsting tool, with 9 nozzles, was lowered down to payzone and perforated 90 tunnels after being moved upward times. Then fracture work conducted 18 m3 sands were squeezed into formations. After that well production reached 11.6 t/d liquid 8.7 oil, respectively, this continued for months. But before job, nothing...

Abstract The placement of multiple fractures in deep horizontal wells is more difficult than that shallow formations due to HTHP conditions. This paper presents the latest advances hydra-jet acid fracturing for solving problems process well fracturing. Basic researches and application evaluations were conducted overcome down-hole Special schedule was designed delicately lower cracking pressure. jet velocity increased 800ft/sec enhance penetration efficiency. Acid pad fluid also jetted target...

Bottom-hole differential pressure is one of the most important factors that affects drilling penetration rate. The purpose article to study effect bottom-hole on vertical stress field. On basis mechanical analysis rock, fluid-solid coupling model with established under axisymmetry condition and solved by using a numerical method. comparison distribution borehole wall between theoretical solution performed verify feasibility rationality model. Then state whole rock break carried out. results...