摘要
新场气田须二气藏为含CO2 气体的CaCl2 水型有水气藏,气井产出水量大,温度在70～90℃之间,矿化度高达114 700 mg/L,气井采气管线、排污管线及排污阀门在生产过程中频繁出现结垢堵塞,严重影响气井正常生产.针对采气流程结垢特征,在对结垢机理分析的基础上采用Scale Chem软件模拟了流体压力、温度、结垢离子浓度及pH值等因素变化对采气流程结垢的影响,理清了产出水结垢机理及结垢主控因素.在此基础上进行了阻垢方法调研并优选出了适宜新场须二气井生产特征的化学阻垢工艺.结合气井产出流体特点,优选具有耐热、耐酸碱性及抗钙盐结垢的XH-442系列阻垢剂开展现场阻垢试验与应用,应用后阻垢率达 97.6%,有效解决了须二气井结垢堵塞问题,保证了气井正常生产.
Abstract
The Xu'er Gas Reservoir of Xinchang Gas Field is a gas reservoir with formation water con-taining CO2,and it is a CaCl2 water-type water-bearing gas reservoir.The gas wells of Xu'er Gas Res-ervoir produce a large amount of water,the temperature of the produced water is between 70℃and 90℃,and the salinity is as high as 114 700 mg/L.Scale blockage frequently appears in the gas produc-tion pipeline,sewage pipeline,and sewage valve of the gas well during the production process,which seriously affects the normal production of the gas well.According to the characteristics of scale formation in the gas production process,based on the analysis of the scale formation mechanism,the Scale Chem software is used to simulate the influence of fluid pressure,temperature,scale ion concentration,and pH value on scale formation in gas production process,and the scale formation mechanism of produced water and the main controlling factors of scale formation are clarified.On this basis,the chemical scale inhibition method is investigated,and the suitable chemical scale inhibition process is selected.Com-bined with the characteristics of the produced fluid in gas wells,the XH-442 series scale inhibitor with heat resistance,acid and alkali resistance,and calcium salt scaling resistance is selected for experimental evaluation.Through experiments,XH-422D scale inhibitor is optimized,and field scale inhibition test and application are carried out.After application,the scale inhibition rate can reach 97.6%,which effectively solves the scale blockage of Xu'er Gas Well and ensures the normal production of the gas well.
维普
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