元坝气田超深高含硫水平井测试投产一体化技术

Integral String Technology of Test and Production for Horizontal Wells in Super Deep Reservoirs with High Content of S

元坝气田长兴组气藏埋深约为7 000 m,温度高达157℃,前期采用测试、投产分步工艺,存在管柱埋卡、工具失效、地层漏失严重等难题,产层二次污染严重,投产时酸化解堵难度加大,费用高,周期长。通过地质研究、力学计算,结合室内管材模拟腐蚀实验,形成了1套测试投产一体化工艺技术。完井方式为衬管,管柱材质根据井温不同选4C或4D类镍基合金,并精简了管柱中工具数量;采用气密封检测技术保证管柱密封可靠性,采取加装封隔器扶正器、底部筛管加长、正反循环坐封封隔器等措施,在降低工程难度的同时保证了工艺的顺利实施。以上工艺和技术,应用在YBXXH井,在天然气绝对无阻流量为600×104m3/d的情况下,一次性完成了测试和投产,为该区域勘探开发提供了有力的技术支持。

The buried depth of Gasfield of Tian Changxing Formation is as deep as 7000m and its reservoir temperature is 157oC.Before adopting the new technology,separate test and commissioning to production were conducted,which have many problems and disadvantages,such as pipe sticking,down hole tool failure,formation leakage to cause secondary damage to formation,difficult plugging-removing in acidizing,high cost and long period.An integral string of test and production is developed based on geology study,mechanical calculation and simulating experiment of pipe corrosion in lab.Liner completion is adopted,the materials of which are nickel base alloy of 4C or 4D according to different temperatures,and down hole tool quantity is cut off;air tight seal is adopted to guarantee the reliability of string sealing;the measures of the installation of packer centralizer,the elongation of bottom screen,packer with direct and reverse circulation are adopted,which not only decrease the difficulty of operation but also guarantee the successful implementation of the technology.The technology above is applied in Well YBXXH.As a result of the application,test and production are successfully conducted with integral string under the open flow capacity of 600×104m3/d,thus providing strong support to the exploration and development of this area.