scholarly journals Research and application of supramolecular gel plugging agent in abnormal pressure reservoir

2021 ◽  
Vol 2045 (1) ◽  
pp. 012006
Author(s):  
B Baletabieke ◽  
Y X Gu ◽  
T Zhou ◽  
D X Duan ◽  
J T Liu ◽  
...  
Keyword(s):  
High Pressure ◽  
Oil And Gas ◽  
Adhesion Force ◽  
Fiber Composite ◽  
Low Pressure ◽  
Effective Rate ◽  
Pressure Zone ◽  
Composite Gel ◽  
Pressure Area ◽  
Strong Adhesion

Abstract The Aktobe project is the largest oil and gas producing area of PetroChina in Central Asia. However, after years of exploitation, the pressure of the reservoir has dropped, making it difficult to increase the production of a single well. Both the Kenkyak block and North Troyes block of the project have induced fractured leakage, and frequent leakage affects safe and efficient drilling and completion operations and production. Therefore, the research on leakage prevention and control technology is very necessary. This article focuses on the characteristics of the cracks in the high-pressure area of the Kenkyak block and the cracks in the low-pressure area of the North Troyes block. Aiming at the fracture characteristics of the high-pressure zone in the Kenkyak block and the low-pressure zone in North Troyes block, and taking advantage of the synergistic effect of supramolecules, a supramolecular plugging-while-drilling agent was developed based on the deformable fiber composite gel. It forms a strong adhesion plugging layer on the inner wall of the leakage channel through the strong adhesion force, and it achieves a good plugging effect. The 300-500mD sand disc bearing pressure could reach 700psi when adding 3% agent, and the bearing pressure of 3-5D permeability sand disc could reach above 450psi. A supramolecular static plugging agent was also developed based on the dilatant gel. It is rich in strong shear reversible gel with supramolecular structure, which guarantees its pumpability and plugging performance. The effective rate of one-time plugging is over 80%, and the viscosity is greatly reduced after the gel is broken for 72hr, which benefits the reservoir protection.

scholarly journals Fall-Off Curves for the Reaction ClO + NO2( + N2) ClONO2 (+N2)

1977 ◽  
Vol 32 (6) ◽  
pp. 648-651 ◽  
Author(s):  
Reinhard Zellner
Keyword(s):  
High Pressure ◽  
Rate Constants ◽  
Low Pressure ◽  
Effective Rate ◽  
Reference Points ◽  
Atmospheric Models ◽  
Chlorine Nitrate ◽  
Pressure Limit

Abstract Fall-off curves for the reaction ClO+NO2(+N2)→ClONO2(+N2) at 300 and 220 K have been calculated from Kassel integrals by use of a theoretically derived high pressure limit and the experimentally determined low pressure limit as reference points. The reaction is found to deviate considerably from the low pressure limit at pressures larger than 10 Torr. Effective rate constants for the use in atmospheric models of chlorine nitrate formation are derived.

scholarly journals Hard time to be parents? Sea urchin fishery shifts potential reproductive contribution of population onto the shoulders of the young adults

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3067 ◽  
Author(s):  
Barbara Loi ◽  
Ivan Guala ◽  
Rodrigo Pires da Silva ◽  
Gianni Brundu ◽  
Maura Baroli ◽  
...  
Keyword(s):  
High Pressure ◽  
Sea Urchin ◽  
Sea Urchins ◽  
Reproductive Potential ◽  
Low Pressure ◽  
Size Class ◽  
High Density ◽  
Pressure Zone ◽  
High Pressure Zone ◽  
Commercial Size

BackgroundIn Sardinia, as in other regions of the Mediterranean Sea, sustainable fisheries of the sea urchinParacentrotus lividushave become a necessity. At harvesting sites, the systematic removal of large individuals (diameter ≥ 50 mm) seriously compromises the biological and ecological functions of sea urchin populations. Specifically, in this study, we compared the reproductive potential of the populations from Mediterranean coastal areas which have different levels of sea urchin fishing pressure. The areas were located at Su Pallosu Bay, where pressure is high and Tavolara-Punta Coda Cavallo, a marine protected area where sea urchin harvesting is low.MethodsReproductive potential was estimated by calculating the gonadosomatic index (GSI) from June 2013 to May 2014 both for individuals of commercial size (diameter without spines, TD ≥ 50 mm) and the undersized ones with gonads (30 ≤ TD < 40 mm and 40 ≤ TD < 50 mm). Gamete output was calculated for the commercial-size class and the undersized individuals with fertile gonads (40 ≤ TD < 50 mm) in relation to their natural density (gamete output per m2).ResultsThe reproductive potential of populations was slightly different at the beginning of the sampling period but it progressed at different rates with an early spring spawning event in the high-pressure zone and two gamete depositions in early and late spring in the low-pressure zone. For each fertile size class, GSI values changed significantly during the year of our study and between the two zones. Although the multiple spawning events determined a two-fold higher total gamete output of population (popTGO) in the low-pressure zone, the population mean gamete output (popMGO) was similar in the two zones. In the high-pressure zone, the commercial-sized individuals represented approximatively 5% of the population, with almost all the individuals smaller than 60 mm producing an amount of gametes nearly three times lower than the undersized ones. Conversely, the high density of the undersized individuals released a similar amount of gametes to the commercial-size class in the low-pressure zone.DiscussionOverall, the lack of the commercial-size class in the high-pressure zone does not seem to be very alarming for the self-supporting capacity of the population, and the reproductive potential contribution seems to depend more on the total density of fertile sea urchins than on their size. However, since population survival in the high-pressure zone is supported by the high density of undersized sea urchins between 30 and 50 mm, management measures should be addressed to maintain these sizes and to shed light on the source of the larval supply.

scholarly journals Caracterización del IHX en un sistema de refrigeración automotriz y el COP con refrigerante R134A

2017 ◽  
Vol 2 (1) ◽  
pp. 45
Author(s):  
Bolívar Cuaical ◽  
Paúl Montúfar
Keyword(s):  
High Pressure ◽  
Standard Deviation ◽  
Heat Exchangers ◽  
Cooling System ◽  
Experimental Tests ◽  
Low Pressure ◽  
Coefficient Of Performance ◽  
Pressure Line ◽  
Pressure Zone ◽  
R 134A

The present work has the objective of characterizing several coaxial heat exchanger geometries in an automotive cooling system and its effect on the performance coefficient, using R-134a as refrigerant by means of experimental tests. In the first instance, the experimental tests were carried out with different geometries of coaxial interchanges involved in the high-pressure line between the condenser and the expansion valve, as well as the low pressure line between the evaporator and the compressor, Between the volume of the exchanger and the coefficient of performance by means of a multifactorial analysis. The development of the research entails complying with parameters for the acquisition of experimental data and the development of an adequate experimental design.  Statistical regressions  were  developed  with  R2  of  86.86%  and  a standard deviation of 2.2 for the low-pressure zone, while for the high pressure zone The regression determined a R2 of 95.17% and a standard deviation of 0.57. As for the COP and the T variables is statistically significant with a value of R2 of 99.97%, thus helping to design the heat exchangers to decrease fuel consumption in vehicles. Index Terms— : IHX,COP, R-134a, Cooling cycle Automotive, heat exchangers

scholarly journals Modernization of Two-Phase Oil and Gas Separator

2020 ◽  
Vol 33 (02) ◽  
pp. 616-622
Author(s):  
Guzel Rafikovna Ganieva ◽  
Putu Aunda Niradgnani
Keyword(s):  
High Pressure ◽  
Gas Separation ◽  
Oil And Gas ◽  
Raw Materials ◽  
Low Pressure ◽  
Technological Scheme ◽  
Operating Costs ◽  
Two Phase ◽  
Oil Separation ◽  
Gas Separator

Separators play an important role in the basis of the technological scheme and field preparation of oil and gas. Separation is the process of oil separation from gas. Depending on the requirements for the feedstock, separators are distinguished according to the principle of operation and purpose. In this paper, the company "PT Pertamina EP Asset 3 Subang", Indonesia (Nirajani) is considered as an example. Dimensions, efficiency, reliability of equipment, capital and operating costs are the main indicators of separator work and productivity. "Subang PT Pertamina EP Asset 3 Subang" collection station has 3 horizontal two-phase separators (high pressure, low pressure and test separator). In 2020, it is planned to increase the extraction of raw materials. In this regard, the aim of this work is to modernize the existing two-phase horizontal separator operated at the field. To achieve this goal, it is necessary to study the design of the existing separator, and calculate its performance (Nirajani). After all the calculations, it is necessary to choose a separator suitable for performance. Modernization of the existing separator is economically feasible for this enterprise.

scholarly journals Forms of grease ice ridges on the south coast of the Baltic Sea

2016 ◽  
Vol 45 (3) ◽  
Author(s):  
Józef P. Girjatowicz
Keyword(s):  
High Pressure ◽  
Baltic Sea ◽  
Low Pressure ◽  
South Coast ◽  
Slip Angle ◽  
The South ◽  
The Baltic Sea ◽  
Pressure Area ◽  
Southern Baltic ◽  
The Baltic

AbstractThe paper presents the forms of grounded grease ice ridges as well as hydrological, meteorological and physiographic conditions of their occurrence on the south coast of the Baltic Sea. The author used results of observations and measurements performed during hiking expeditions and analyzed profiles and photographs showing the morphology of grease ice ridges which occur along the coast and are usually several meters wide and 1-3 m high. Their windward slopes are very steep, usually concave, with abrasion niches and ice cornices formed by waves. The leeward slopes are gentle (20-30°) and coincident with the angle of the natural slip (angle of slide) of the grease ice, slush and shuga tossed by waves. The major factor leading to grease piling is the movement of waves generated by a strong onshore (NW, N, NE) wind. Such wind conditions occur mainly when a low-pressure area extends to the E, SE and/or S of the southern Baltic, and a high-pressure area – to the W, NW and/or N.

Fouling Is the Beginning: Upcycling Biopolymer-Fouled Substrates for Fabricating High-Permeance Thin-Film Composite Polyamide Membranes

2020 ◽  
Author(s):  
Ruobin Dai ◽  
Hongyi Han ◽  
Tianlin Wang ◽  
Jiayi Li ◽  
Chuyang Y. Tang ◽  
...  
Keyword(s):  
Thin Film ◽  
High Pressure ◽  
End Of Life ◽  
Water Purification ◽  
Low Pressure ◽  
Polymeric Membranes ◽  
Membrane Recycling ◽  
Film Composite ◽  
Thin Film Composite ◽  
First Time

Commercial polymeric membranes are generally recognized to have low sustainability as membranes need to be replaced and abandoned after reaching the end of their life. At present, only techniques for downcycling end-of-life high-pressure membranes are available. For the first time, this study paves the way for upcycling fouled/end-of-life low-pressure membranes to fabricate new high-pressure membranes for water purification, forming a closed eco-loop of membrane recycling with significantly improved sustainability.

scholarly journals High-Pressure Spectroscopy Study of Zn(IO3)2 Using Far-Infrared Synchrotron Radiation

Crystals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 34
Author(s):  
Akun Liang ◽  
Robin Turnbull ◽  
Enrico Bandiello ◽  
Ibraheem Yousef ◽  
Catalin Popescu ◽  
...  
Keyword(s):  
High Pressure ◽  
Phase Transitions ◽  
Synchrotron Radiation ◽  
Infrared Radiation ◽  
Room Temperature ◽  
Far Infrared ◽  
Low Pressure ◽  
Pressure Response ◽  
Spectroscopy Study ◽  
Far Infrared Radiation

We report the first high-pressure spectroscopy study on Zn(IO3)2 using synchrotron far-infrared radiation. Spectroscopy was conducted up to pressures of 17 GPa at room temperature. Twenty-five phonons were identified below 600 cm−1 for the initial monoclinic low-pressure polymorph of Zn(IO3)2. The pressure response of the modes with wavenumbers above 150 cm−1 has been characterized, with modes exhibiting non-linear responses and frequency discontinuities that have been proposed to be related to the existence of phase transitions. Analysis of the high-pressure spectra acquired on compression indicates that Zn(IO3)2 undergoes subtle phase transitions around 3 and 8 GPa, followed by a more drastic transition around 13 GPa.

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