Research Article
Optimization and Application of Wax Removal Technology for Fixed Tubing String in Offshore Wells
Weigang Du*
,
Zhenli Pang,
Zhi Cao,
Guoqiang Xu
Issue:
Volume 12, Issue 2, June 2024
Pages:
26-31
Received:
18 March 2024
Accepted:
22 April 2024
Published:
29 April 2024
Abstract: This study focuses on the selection and application of wax removal techniques tailored for fixed tubing columns in offshore wells that have been obstructed by wax deposits. Initially, the paper delves into the importance of well decommissioning and examines prevalent decommissioning techniques, outlining their respective advantages and limitations. Subsequently, three distinct unblocking technologies are proposed, tailored to address different causes and scenarios of well clogging: physical plugging removal technology, chemical treatment technology, and mechanical unblocking technology. Each technology is thoroughly analyzed, discussing their applicable scopes, operational procedures, equipment and anticipated effectiveness in removing blockages. To validate the feasibility and practicality of these proposed unblocking methods, an actual offshore well case study is conducted. The results demonstrate that thermal nitrogen wax removal technology emerges as the most effective approach, necessitating further optimization of its application. The paper then details the oil-filed implementation of this technology, including methods for generating hot nitrogen and its subsequent application. Following the implementation, significant improvements in wax removal and unblocking are observed, attesting to the technology's effectiveness. The findings of this study offer valuable insights and practical guidance for addressing wax blockage issues in fixed tubing columns of offshore oil wells. By providing a comprehensive analysis of different unblocking techniques and their application in oil-filed, this paper contributes to enhancing the efficiency and reliability of offshore oil production operations.
Abstract: This study focuses on the selection and application of wax removal techniques tailored for fixed tubing columns in offshore wells that have been obstructed by wax deposits. Initially, the paper delves into the importance of well decommissioning and examines prevalent decommissioning techniques, outlining their respective advantages and limitations....
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Research Article
Gas Composition Tracking in a Transient Pipeline Using the Method of Characteristics
Issue:
Volume 12, Issue 2, June 2024
Pages:
32-42
Received:
6 May 2024
Accepted:
17 June 2024
Published:
19 June 2024
Abstract: For a gas pipeline with multiple gas sources, the significance of tracking the composition of natural gas is increasing with the implementation of X+1+X system for the natural gas industry in China. Mathematically, the tracking problem is usually described by a system of partial differential equations (PDEs). The continuity equation on gas composition has been developed to track natural gas composition according to the law of mass conservation. The algorithm resulting from the method of characteristics (MOC) is proposed to solve the system of PDEs. Compared to the original MOC, numerical solutions of the continuity equation on gas composition are obtained after the hydraulic calculation and thermal calculation. Moreover, different combinations of boundary conditions for the MOC are derived, which could expand the range of application of the MOC and be applicable to various operating conditions. The heating values of diverse gas sources have been determined following the methods documented in ISO 6976:2016. The case study of a gas pipeline in China verified the validity of the algorithm via the commercial simulation software Pipeline Studio for Gas (TGNET). The heating value and gas composition obtained by the algorithm can be used in the custody transfer metering of natural gas pipelines for Class B and C metering stations described in GB/T 18603−2014.
Abstract: For a gas pipeline with multiple gas sources, the significance of tracking the composition of natural gas is increasing with the implementation of X+1+X system for the natural gas industry in China. Mathematically, the tracking problem is usually described by a system of partial differential equations (PDEs). The continuity equation on gas composit...
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Research Article
Study and Simulation of a Thermal Photovoltaic Hybrid Sensor
Abdoul Aziz Ouiminga*,
Bouwèreou Bignan-Kagomna,
Mariatou Zon,
Sié Kam
Issue:
Volume 12, Issue 2, June 2024
Pages:
43-52
Received:
24 May 2024
Accepted:
11 June 2024
Published:
25 June 2024
Abstract: Photovoltaic systems have undergone many recent devel-opments in terms of improving their energy efficiency. One of these performance improvement innovations is: the com-bination of thermal exploitation of solar energy with photo-voltaic exploitation on the same sensor for the simultaneous production of heat and electricity. This study aims to study the electrical and thermal perfor-mances of the system by evaluating the electrical and ther-mal efficiency as well as the electrical power for a hybrid photovoltaic/thermal sensor. In this work, the results of an experimental and numerical study on the thermal behavior of the hybrid sensor are presented and discussed. The experimental study made it possible to determine the electrical characteristics of the PV/T, the sunshine and the ambient temperature for a typical day. The mathematical equations which govern the operating principle of our PV/T are described and solved using the RANGE KUNTA method of order 4 for a numerical study of the efficiency of our PV/T. The numerical results obtained indicate a thermal efficiency of our PVT of 10.5% for a speed of 5 m/s and 7.8% for a speed of 1m/s. Increasing the number of exchange tubes to cover the entire surface of the sensor makes it possible to improve the minimum efficiency from 7.8% to 11.68% for a wind speed of 1m/s. The results obtained suggest that this type of sensor constitutes a good alternative to photovoltaic modules and conventional thermal sensors installed separately.
Abstract: Photovoltaic systems have undergone many recent devel-opments in terms of improving their energy efficiency. One of these performance improvement innovations is: the com-bination of thermal exploitation of solar energy with photo-voltaic exploitation on the same sensor for the simultaneous production of heat and electricity. This study aims to stud...
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