致密气井下节流工艺技术应用与研究
Application and Research of Downhole Throttling Technology for Tight Gas Wells

川中金秋致密气田具有低渗透、低产能的特点，在气田开采及集输过程中，由于井口压力高，井口压力与管道输压压差大，地面易形成水合物，导致输气量减少，出现管线堵塞现象，严重影响气田生产的正常运行，为此开展井下节流技术的研究与应用具有重要的实际意义。为解决此类问题，同时为后续优化简化地面采输流程、提高开发经济效益，本研究针对川中致密气田气井生产特征和管柱特点，特别是致密气在生产过程中持续出砂，且砂粒很细，节流器的防砂工艺进行技术攻关，成功研制2 3/8in新型活动式井下节流器以及配套作业工具，并在致密气井开展井下节流工艺现场应用20余井次，同时持续跟踪气井生产情况，制定合理的维护制度。结果表明，安装了井下节流器的气井，改为井下节流工艺生产后实现井筒节流降压，有效避免水合物的生成，取消地面加热装置，优化简化地面建设和后期运行成本，实现致密气规模效益开发。
The Jinqiu tight gas field in central Sichuan is characterized by low permeability and low productivity. In the process of gas field exploitation and gathering and transportation, because of high wellhead pressure and large difference between wellhead pressure and pipeline pressure, hydrate is easy to form on the surface, therefore, the research and application of downhole throttling technology is of great practical significance. It will lead to the decrease of gas transmission and pipeline blockage. In order to solve these problems, and to optimize and simplify the surface production and transportation process and improve the economic benefits of development, this study aims at the production characteristics and string characteristics of gas wells in Chuanzhong tight gas field, in particular, the dense gas continuously sanded out in the production process, and the sand particles were very fine, the sand control technology of the throttles was studied, and a new type of downhole throttling device of 2 3/8in was successfully developed. The downhole throttling technology has been applied more than 20 times in the field of tight gas wells, at the same time, the production situation of gas wells has been continuously followed, and a reasonable maintenance system has been formulated. The results show that the downhole throttling process can effectively reduce the pressure and reduce the formation of hydrate and cancel the surface heating device in gas wells with downhole throttling, optimizing and simplifying the ground construction and later operation costs, to achieve tight gas scale benefit development.