Novel Spherical Polymer Sealing Agent for Oil-Based Drilling Fluids to Overcome Borehole Instability Problem in Low Permeability Reservoirs

2020 ◽  
Vol 842 ◽  
pp. 290-296 ◽  
Author(s):  
Long Li ◽  
Rong Chao Cheng ◽  
Cha Ma ◽  
Jie Zhang

Due to borehole instability problem in low permeability formations, a new type of spherical polymer sealing agent (OLBS) for oil-based drilling fluids was prepared via suspension polymerization, and the sealing effect of polymer sealing agent on low permeability cores was evaluated. The results indicated that OLBS had no influence on the rheological properties of oil-based drilling fluids. The core displacement experiments indicated that OLBS could reduce the core permeability by a significant amount, and thus stop fluid invasion into the formations, so OLBS could provide an excellent sealing effect and improve wellbore strength. Using this polymer sealing agent to plug the low permeability formations is a very powerful approach to address borehole instability problem in troublesome low permeability formations. This sealing agent is suitable for the drilling of long sections of horizontal laterals. In the future, the oil-based drilling fluids containing OLBS might hold great promise to resolve borehole instability problem in low permeability formations.

Author(s):  
Wen-sheng Liao ◽  
Li-min Wang ◽  
Yi-xuan Yao ◽  
Guo-ping Jiang ◽  
Hai-jun Zhao ◽  
...  

Acidization was studied on a uranium sandstone deposit in Inner Mongolia with low–permeability and heavy calcium cementation. Acid dissolving test indicates that hydrochloric acid, formic acid and mud acid can easily dissolve formation minerals. With proper volumes and concentrations of acids used, the risk of precipitation of reaction products could be minimized. Core flow acidizing trial shows that the acidic fluid systems of hydrochloride acid, formic acid or acetic acid can significantly improve the core permeability. The average permeability has increased by 763 percent for the above three systems. But mud acid didn’t increase the core permeability; on the contrary, it caused formation damage, and led to lowering permeability. In the pilot test, the injection rate has improved by 118 percent for 6 wells. The acid treatment results indicate that a significant production enhancement of wellfields can be achieved by acid stimulation.


2015 ◽  
Vol 719-720 ◽  
pp. 561-566
Author(s):  
Yong Qing Gao ◽  
Dan Shanng

Firstly, this paper analyzes the significance and demand of intelligent power. Then a solution of home intelligent power system based on ZigBee is proposed. Hardware components of the solution proposed in this work mainly consists of AT91SAM9G20 as the core of the home gateway controller, CC430F6137 as the core of the network node of intelligent power and construction of intelligent home network system. This paper mainly introduces a new type of home intelligent power consumption network node, which realizes the measurement of electric power parameter, monitoring, overload protection and timing control, the communication between home gateway and network node through ZigBee protocol, the intelligent household electricity. By testing and using, it can meet the aspects of everyday life needs of user in convenient life, intelligent life and energy-saving, etc. It brings great commercial return and technical value to the development and application of intelligent home in future, as well as far-reaching impact to improving the quality of intelligent home services.


2012 ◽  
Vol 490-495 ◽  
pp. 594-597
Author(s):  
Cheng Qun Li ◽  
Liang Gao

This paper introduces a new type of automatic steel bundling machine for bundling process, which includes a pneumatic action process, mainly do some researches on the pneumatic control system. The system chooses PLC as the core control component, puts forward the hardware of control system and control flow. Eventually we have been designed the control program.


2021 ◽  
Author(s):  
Nicolas Gaillard ◽  
Matthieu Olivaud ◽  
Alain Zaitoun ◽  
Mahmoud Ould-Metidji ◽  
Guillaume Dupuis ◽  
...  

Abstract Polymer flooding is one of the most mature EOR technology applied successfully in a broad range of reservoir conditions. The last developments made in polymer chemistries allowed pushing the boundaries of applicability towards higher temperature and salinity carbonate reservoirs. Specifically designed sulfonated acrylamide-based copolymers (SPAM) have been proven to be stable for more than one year at 120°C and are the best candidates to comply with Middle East carbonate reservoir conditions. Numerous studies have shown good injectivity and propagation properties of SPAM in carbonate cores with permeabilities ranging from 70 to 150 mD in presence of oil. This study aims at providing new insights on the propagation of SPAM in carbonate reservoir cores having permeabilities ranging between 10 and 40 mD. Polymer screening was performed in the conditions of ADNOC onshore carbonate reservoir using a 260 g/L TDS synthetic formation brine together with oil and core material from the reservoir. All the experiments were performed at residual oil saturation (Sor). The experimental approach aimed at reproducing the transport of the polymer entering the reservoir from the sand face up to a certain depth. Three reservoir coreflood experiments were performed in series at increasing temperatures and decreasing rates to mimic the progression of the polymer in the reservoir with a radial velocity profile. A polymer solution at 2000 ppm was injected in the first core at 100 mL/h and 40°C. Effluents were collected and injected in the second core at 20 mL/h and 70°C. Effluents were collected again and injected in the third core at 4 mL/h and 120°C. A further innovative approach using reservoir minicores (6 mm length disks) was also implemented to screen the impact of different parameters such as Sor, molecular weight and prefiltration step on the injectivity of the polymer solutions. According to minicores data, shearing of the polymer should help to ensure good propagation and avoid pressure build-up at the core inlet. This result was confirmed through an injection in a larger core at Sor and at 120°C. When comparing the injection of sheared and unsheared polymer at the same concentration, core inlet impairment was suppressed with the sheared polymer and the same range of mobility reduction (Rm) was achieved in the internal section of the core although viscosity was lower for the sheared polymer. Such result indicates that shearing is an efficient way to improve injectivity while maximizing the mobility reduction by suppressing the loss of product by filtration/retention at the core inlet. This paper gives new insights concerning SPAM rheology in low permeability carbonate cores. Additionally, it provides an innovative and easier approach for screening polymer solutions to anticipate their propagation in more advanced coreflooding experiments.


2021 ◽  
Author(s):  
Jennifer E. Bauer ◽  
Imran A. Rahman

Imaging and visualizing fossils in three dimensions with tomography is a powerful approach in paleontology. Here, the authors introduce select destructive and non-destructive tomographic techniques that are routinely applied to fossils and review how this work has improved our understanding of the anatomy, function, taphonomy, and phylogeny of fossil echinoderms. Building on this, this Element discusses how new imaging and computational methods have great promise for addressing long-standing paleobiological questions. Future efforts to improve the accessibility of the data underlying this work will be key for realizing the potential of this virtual world of paleontology.


2012 ◽  
Vol 166-169 ◽  
pp. 3277-3281
Author(s):  
Min Tong

Abstract. Connection joint with penetrated diaphragm, which is better for the stressing state of the welding connection, is a new type joint for the beam and column connection. Static test and pseudo-static test are put to 17 crossing joints. The stress distribution of the steel beam and the penetrated diaphragm are discussed. The experiment shows that the penetrated diaphragm transfer most tension force of the steel beam’s upper flange to the core region of the joint, which could effectively decrease the stress and strain gradient within the connection area of the steel beam’s upper flange and steel tube column. As the result, the shear force of the core region is decreased. The front weld is avoided being surfing great tension. The ductility of the joint and the energy dissipation capacity of the structure are then increased. The type and the size of the penetrated diaphragm show great affection to the stress distribution of steel beam and penetrated diaphragm. The study achievement enriches the joint connection type of the composite structure with concrete- filled steel tube.


Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-18 ◽  
Author(s):  
Biao Ma ◽  
Xiaolin Pu ◽  
Zhengguo Zhao ◽  
Hao Wang ◽  
Wenxin Dong

The lost circulation in a formation is one of the most complicated problems that have existed in drilling engineering for a long time. The key to solving the loss of drilling fluid circulation is to improve the pressure-bearing capacity of the formation. The tendency is to improve the formation pressure-bearing capacity with drilling fluid technology for strengthening the wellbore, either to the low fracture pressure of the formation or to that of the naturally fractured formation. Therefore, a laboratory study focused on core fracturing simulations for the strengthening of wellbores was conducted with self-developed fracture experiment equipment. Experiments were performed to determine the effect of the gradation of plugging materials, kinds of plugging materials, and drilling fluid systems. The results showed that fracture pressure in the presence of drilling fluid was significantly higher than that in the presence of water. The kinds and gradation of drilling fluids had obvious effects on the core fracturing process. In addition, different drilling fluid systems had different effects on the core fracture process. In the same case, the core fracture pressure in the presence of oil-based drilling fluid was less than that in the presence of water-based drilling fluid.


2021 ◽  
Vol 248 ◽  
pp. 01054
Author(s):  
Zhigang Wang ◽  
Yun Xiang ◽  
Ziqi Yi ◽  
Longfei He ◽  
Mingjie Chen ◽  
...  

Insulation pull rods are commonly used tools and instruments in the replacement of insulators for live work. Traditional hard insulated pull rods are difficult to transport and assemble due to their large deflection, especially due to the long and heavy weight of insulated pull rods used in UHV live operations, the difficulties in the above links are more obvious. In view of the existing problems in the use of the existing insulated pull rods, by studying the overall processing type, the soft pull rod weaving process, the technology of tightly combining the core rod and the protective cover, the technology of connecting the core rod and the metal, etc., a new type suitable for live transmission lines has been developed. Large-tonnage soft insulated pull rod for operation. Effectively solve a series of problems caused by the large deflection of the hard insulated pull rod.


Author(s):  
M.B. Rarenko ◽  

The article considers the story by Henry James (1843 – 1916) «The Turn of the Screw» (1898 – first edition, 1908 – second edition) in connection with the emergence of a new type of narrator in the writer's late prose. The worldview and creative method of H. James are formed under the influence of the philosophy of pragmatism, which became widespread at the turn of the XIX-XX centuries thanks to the works of the writer's elder brother, the philosopher William James (1842 – 1910). The core of pragmatism is the pluralistic concept of William James based on the assumption that knowledge can be realized from very limited, incomplete, and inadequate «points of view» and this leads to the statement that the absolute truth is essentially unknowable. The epistemological statements of William James's theory is that the content of knowledge is entirely determined by the installation of consciousness, and the content of the truth in this case depends on the goals and experience of the human, i.e. the central starting point is the consciousness of the person. Henry James not only creates works of art, but also sets out in detail the principles of his work both on the pages of fiction works of small and large prose, putting them in the mouths of their characters – representatives of the world of art, and in the prefaces to his works of fiction, as well as in critical works.


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