页岩气井井下节流工艺的研究与应用

发布时间：2018-03-08 19:00

本文选题：页岩气　切入点：井下节流技术　出处：《西南石油大学》2015年硕士论文　论文类型：学位论文

【摘要】：世界对于天然气的需求量随着经济的快速发展也在飞速增长。预计21世纪天然气将会成为主要能源。近些年,虽然我国的天然气产业得到了长足的发展,特别是在页岩气开发领域不断取得进步,但整体水平还比较低。因此,天然气的发展空间较大,发展前景较好。在天然气的开采过程中,水合物的生成问题给气井的生产带来了一系危害及困难,如油管、计量孔板、地面管线的阻塞以及阻碍设备的热传导等。这些问题轻则严重影响到气井的正常生产,重则危及人与设备的安全。页岩气属于超低渗透致密砂岩天然气。研究表明,页岩气在我国具有大量发育的区域地质条件,初步计算我国页岩气资源量约为(15-30)×1012m3。近年来,随着美国页岩气革命的影响下,在中国国内进行了大规模的页岩气勘探、开发,但目前我国对于页岩气勘探开发关键技术仍处于落后状态。如何更好的开发页岩气成为一个重大的问题。鉴于这一现状,本文开展了页岩气井井筒水合物形成机理和防治工艺的研究,分析和总结了井下节流的基本原理,提出了井筒压力及温度的预测模型、节流后压降温降的预测模型以及水合物生成的预测模型,并对井下节流工艺参数的设计原理、思路及过程进行了阐述。在此基础上,将本文所建模型与模拟软件Flue nt相结合,以一口页岩气井生产实际为对象,对井下节流过程进行模拟,结合模拟的结果对节流嘴的流动状态、规律及特征进行分析和总结。最后将实际生产的真实数据引入本文所建模型中,获取井下节流工艺运行参数,再与实际工艺参数设置进行对比、分析,从而对所建模型进行优化和完善。本文所建立的井筒压力温度预测模型及节流嘴压降温降预测模型的模拟结果与实际生产数据之间的误差也在允许的范围之内,能较好地运用于工程实际之中。本文的节流工艺参数设计方法的理论计算结果与实际生产情况之间的误差同样在允许的范围之内,是有效可行的一种设计方法。此外,本文通过Fluent软件建立的模型计算结果与前面的理论分析情况基本相符,这对节流井筒的流场分布情况以及节流嘴的流动情况具有重要意义。本文的研究对天然气水合物生成的预测及防治具有重大指导意义。
[Abstract]:The demand for natural gas in the world is also increasing rapidly with the rapid development of economy. In 21th century, it is expected that natural gas will become the main energy source. In recent years, although the natural gas industry in China has made great progress, Especially in the field of shale gas development, progress has been made continuously, but the overall level is still relatively low. As a result, natural gas has a larger development space and a better development prospect. The formation of gas hydrate has brought a series of harm and difficulties to the production of gas wells, such as tubing, metering orifice, blocking of surface pipelines and hindering the heat conduction of equipment, etc. These problems seriously affect the normal production of gas wells. Heavy endangers the safety of people and equipment. Shale gas belongs to ultra-low permeability tight sandstone gas. The study shows that shale gas has a large number of regional geological conditions in China, and the preliminary calculation of shale gas resources in China is about 15-30) 脳 1012m3.In recent years, with the influence of the shale gas revolution in the United States, A large scale of shale gas exploration and development has been carried out in China, but at present the key technology of shale gas exploration and development in China is still lagging behind. How to develop shale gas better becomes a major problem. In view of this situation, this paper studies the formation mechanism and prevention technology of gas hydrate in shale gas wells, analyzes and summarizes the basic principle of downhole throttling, and puts forward the prediction model of wellbore pressure and temperature. The prediction model of pressure drop after throttling and the prediction model of hydrate formation are described. The design principle, train of thought and process of downhole throttling process parameters are described. On this basis, the model is combined with the simulation software Flue NT. Taking the actual production of a shale gas well as an example, the downhole throttling process is simulated, and the flow state of the throttle nozzle is combined with the simulation results. Finally, the real data of actual production is introduced into the model established in this paper, and the operation parameters of downhole throttling process are obtained, and then compared with the actual process parameters. In order to optimize and improve the model. The error between the simulation results of the wellbore pressure temperature prediction model and the throttling nozzle pressure drop prediction model and the actual production data is also within the allowable range. The error between the theoretical calculation results of the design method of throttling process parameters and the actual production conditions is also within the allowable range, which is an effective and feasible design method. The calculation results of the model established by Fluent software in this paper are basically consistent with the previous theoretical analysis, which is of great significance to the flow field distribution of the throttling wellbore and the flow situation of the throttle nozzle. The research in this paper is of great significance for the prediction and prevention of gas hydrate formation.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE37

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