http://yetl.yabesh.ir/yetl1/handle/yetl/19031 2026-04-28T13:01:16Z 2026-04-28T13:01:16Z Jun Zhou Longyu Chen Guangchuan Liang Zonghang Zhou Penghua Du http://yetl.yabesh.ir/yetl1/handle/yetl/4309634 2026-02-16T21:43:34Z 2025-01-01T00:00:00Z

Cost-Effective Scheduling of Modular Equipment in Shale Gas Gathering Systems with Hydraulic Considerations Jun Zhou; Longyu Chen; Guangchuan Liang; Zonghang Zhou; Penghua Du The scheduling of modular equipment (ME) in gathering systems is related to not only node pressure but also the production of shale gas. As shale gas continues to be extracted, its production decreases, leading to continuous changes in the load rates of ME and various operating conditions. Although considerable research exists on the scheduling of ME, multiple types of ME and incorporating the hydraulic characteristics of the pipeline network are less common. For shale gas gathering system (SGGS), this paper has established a multitype ME scheduling optimization model coupled hydraulic characteristics (MMESH-model). The objective function of the model is to minimize total equipment cost, and the model is subject to the following constraints: pressure, compressor, well and platform throttling, node pressure balance, flow balance, nonpressurized equipment handling capacity, multitype ME scheduling, and equipment utilization. A case study is discussed to prove the proposed model. The scheduling scheme of the ME is obtained, which is different from that of the actual site. In the early stages of production, platform pressures could reach 9.87 MPa, whereas the station requires an external transmission pressure of 5.91 MPa. A platform pressure of 6.046 MPa suffices in the first year, eliminating the need for a compressor. Moreover, the separator is relocated 11 times, the dehydrator is not relocated, and the compressor is relocated eight times. In addition, the cost analysis shows that the procurement and operating costs of ME are much higher than other costs. As a result, a new method for optimizing ME in SGGS with coupled hydraulic calculation is developed, and this method has some guiding implications for SGGS operation and production.

2025-01-01T00:00:00Z Yujiang Shi Shaocheng Luo Yabin Yao Huaimin Dong Daojie Cheng Cuixia Qu Yu Mu Na Li http://yetl.yabesh.ir/yetl1/handle/yetl/4309633 2026-02-16T21:43:32Z 2025-01-01T00:00:00Z

Experimental Study of the Effect of Clay Minerals on the Electrical Characteristics of Clayey Silt Hydrate-Bearing Sediments Yujiang Shi; Shaocheng Luo; Yabin Yao; Huaimin Dong; Daojie Cheng; Cuixia Qu; Yu Mu; Na Li The mineral composition and content vary greatly in different layers of the clayey silt hydrate-bearing reservoirs in the South China Sea, and the changes in mineral composition and content directly affect the formation and dissociation characteristics of gas hydrates, resulting in differences in electrical characteristics, especially the changes in clay mineral type and content, which have a more significant impact on the hydrate-bearing sediments. In this investigation, the effects of clay mineral types and contents on the synthesis and electrical characteristics of clayey silt hydrate-bearing sediments were studied by simulating the formation and dissociation of gas hydrates. Besides, the microscopic characteristics of gas hydrates were analyzed by high-precision X-ray computed tomography (CT) scanning technology, and the macroscopic electrical behavior mechanism of clayey silt hydrate-bearing sediments containing different clay minerals was revealed. The results show that the formation rate and dissociation rate of montmorillonite silt hydrate-bearing sediments are lower than those of illite silt hydrate-bearing sediments under the same formation and dissociation conditions. Besides, the resistivity of illite silt hydrate-bearing sediments is more significantly affected by gas hydrates. During the process of formation and dissociation, the resistivity of illite silt hydrate-bearing sediments with the same gas hydrate saturation is higher than that of montmorillonite samples.

2025-01-01T00:00:00Z Lei Cao Guofa Ji http://yetl.yabesh.ir/yetl1/handle/yetl/4309631 2026-02-16T21:43:28Z 2025-01-01T00:00:00Z

Research on the Influence of Various Factors Inside the Wellbore on Liquid Holdup and Gas–Liquid Ratio Lei Cao; Guofa Ji The changes in liquid holdup and gas–liquid ratio during wellbore oil and gas extraction have a significant impact on the development of oil and gas fields. To comprehensively explore the influence of various factors on liquid holdup and gas–liquid ratio, this study is based on a transient flow mathematical model and a unified two-phase flow pattern. Horizontal and vertical wellbore models are established using multiphase flow transient simulation software OLGA, based on phase equilibrium and mechanical analysis. The focus was on analyzing the effects of factors such as inlet temperature, inlet pressure, flow rate, wellbore diameter, and inclination angle on wellbore holdup and gas–liquid ratio. The reasons for flow pattern changes and the physical mechanisms of changes in holdup and gas–liquid ratio at each node were discussed in detail. Using the random forest method, the variation data of gas–liquid ratio and liquid holdup under different factors were analyzed to quantify the degree of influence of each factor on gas–liquid ratio and liquid holdup. The research results can be used to determine the optimal construction parameters in practical engineering and provide key guidance for oil and gas field production design and resource utilization maximization.

2025-01-01T00:00:00Z Jin Yan Xiaoming Ni Xiaolei Liu Shuai Heng http://yetl.yabesh.ir/yetl1/handle/yetl/4309630 2026-02-16T21:43:26Z 2025-01-01T00:00:00Z

Experimental Research into the Initiation and Propagation of Hydraulic Fractures in Coal Combinations with Different Strengths Jin Yan; Xiaoming Ni; Xiaolei Liu; Shuai Heng The fracture initiation location and expansion mode are important indexes to evaluate the fracturing effect during the hydraulic fracturing of a coal seam. However, the initiation location and propagation of hydraulic fractures in different-strength coal assemblages are still unclear. For this reason, physical simulation experiments on the initiation and propagation of hydraulic fractures in coal composite with different strength were carried out. According to the difference of fracture initiation position, pumping pressure curve, and propagation trend, three fracture initiation modes, three fracture propagation modes, and four fracture morphology are classified. The formation mechanism of different fracture forms is revealed. The results show that with different-strength coal combinations, the strength difference leads to joint crack initiation, and the single main crack is formed only in low-strength coal with crack propagation and weak structural plane crack propagation. The strength difference leads to joint cracking, and only in low-strength coal, high-strength coal expansion, and structural plane expansion is a single cross crack formed. Multiple clusters of independent fractures are formed by strength difference leading to coinitiation, stress difference leading to coinitiation, low-strength coal expansion, and weak structural plane expansion. Strength difference leads to joint cracking, and stress difference leads to joint cracking, lows trength coal expansion, and high-strength coal expansion to form multiple clusters of network cracks. When the vertical stress difference is 3 to 4 MPa and the stress difference coefficient is 0.3 to 0.4, the complex fracture network can be formed. It is concluded that reducing the number of perforations of low-strength coal can improve the influence of strength difference on fracturing effect. The results provide experimental support for the initiation and propagation behavior of hydraulic fractures in coal combinations with different strengths.

2025-01-01T00:00:00Z