安靖区块GX排气井井筒堵塞机理及解堵研究

Mechanism of Wellbore Plugging and Blockage Removal of GX-row Wells in Anjing District

研究了靖边气田安靖区块GX排气井井筒堵塞机理,研发了新型解堵剂,并在现场试验获得良好的增气效果。对样本井采出水样进行了化学组分分析,通过专门方法或软件,预测了水样的结垢和腐蚀性能,得出现场水样具有严重的CaCO_(3)结垢趋势和对管串腐蚀特性,并且其程度都随井深而增加。对现场堵塞物样品通过化学、XRD、红外等分析手段,得出约占80%的无机组分是地层出水结垢和腐蚀所致;约占20%的有机组分来自于入井药剂的残留物或反应衍生物。最后借助金相显微镜、微观3D形貌、EDS等分析测试,开展了腐蚀和结垢模拟实验,进一步证明井筒发生堵塞是由腐蚀、结垢、有机衍生物等多因素综合作用的结果。以此研发了新型解堵剂FFS-01和FFS-02,在现场试验2口井,试验井解堵后投产3个月累积实现增气130×10^(4) m^(3)。

This paper studies the mechanism of wellbore plugging in GX-row of gas wells in Anjing district of Jingbian Gasfield,and develops two novel plug removal agents applied excellently in practice.By analyzing the chemical composition of the samples taken randomly from production water,predictions of the scaling of calcium carbonate(CaCO_(3))and the corrosion on strings are made by the special method or software.The study shows that there are high scaling of CaCO_(3) and strong corrosion performance on strings in the production water,the seriousness of both enhances as the well depth increases.Through the analysis and experiment of sample of blockages from site by chemical,XRD and infrared spectrum,the research shows that inorganic components of blockage accounting for about 80%are made from the scaling and corrosion of production water while about 20%of organic comes from residues or derivatives of chemical agents put into wells.Then,simulation experiments on scaling and corrosion are carried out by means of metal-scope,micro 3D morphology,and energy disperse spectroscopy(EDS),which further proves that the blockages are the result of multiple factors:scaling,corrosion,as well as residues or derivatives of agents into wells.Finally,two novel plug removal agents(FFS-01,FFS-02)are developed indoor and the application of new agents is carried out in the gas wells.The total production of two wells has added up to 130*10^(4) m^(3) of gas during three months since the new agents were put into use.