Abstract
A constraint of the development of gas hydrate is the phase change that may cause engineering losses in the mining process, which tends to be clogged in the section of well completion (sieve section: wellbore lifting section). The flow of gas hydrate in the well completion section was simplified using the T-type pipe confluence model in this paper. The temperature and pressure coupling model in the confluence section was derived first, followed by the use of the Fluent software to simulate its gradient changes in the T-type model. Then, the physical model and the experiment were designed to study the velocity changes. Finally, the contrast analysis between experiment and numerical simulation was carried out. Through the study of this paper, it is possible to prevent blockage in the well completion section during the process of depressurization, which can provide theoretical guidance for the control of pressure drop when gas hydrate is produced.
Highlights
Gas hydrate is a kind of crystalline material formed by natural gas and water in the low-temperature and highpressure environment [1], most of which is distributed in continental permafrost, polar continental shelf, and deep water [2]
There still exists a problem of phase change during the exploitation of gas hydrate, which seriously restricts its development as energy
Under the production condition of the natural gas hydrate pressure drop method, gas hydrates in underground reservoirs move with the change in environmental pressure and are mainly decomposed into methane and water [4]. e decomposition of natural gas hydrate releases formation water, sand, and mud into the sand control screen pipe which enters the wellbore. ere exists multiphase flow confluence in the hole part of the screen pipe [5]. erefore, it is of great significance to describe the confluence flow law for gas hydrate production
Summary
Gas hydrate is a kind of crystalline material formed by natural gas and water in the low-temperature and highpressure environment [1], most of which is distributed in continental permafrost, polar continental shelf, and deep water [2]. Anmadi et al designed the one-dimensional model of gas hydrate single well mining for numerical simulation of the pressure drop mining method [7]; Li et al established a model to analyze the gas hydrate flow law under different production pressures and formation temperatures [8]; Huang et al regarded. These research studies mainly focus on the mechanism of blockage caused by phase change when gas hydrate flowed in the wellbore, while ignoring the clogging phenomenon at the confluence of the completion section during the production process [12, 13]. The large pressure drop and temperature drop cause the phase of gas hydrate to change, which result in the formation of solid gas hydrate particles and the blockage of pipes [14, 15]. The research results could provide the technical basis for preventing gas hydrate blocking measures
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
