考虑产水量变化的气井井筒结垢堵塞预测

Prediction of Scaling and Plugging in Gas Well Wellbore Considering Change of Water Production

为提高气井解堵措施的针对性,综合考虑气井井筒无机物结垢的热力学和动力学影响,特别是考虑气井产水量变化与垢在井筒内壁的黏附系数,建立了气井井筒结垢堵塞预测模型,并应用于靖边气田。结果表明:基于平滑指数法预测了气井日产水量,预测时间越长,累积产水量的误差越小。加权系数α越小,预测结果越精准,模型中α取0.2;通过现场生产资料拟合,垢在井筒内壁的黏附系数取0.001时,能够取得较为满意的预测结果;现场应用结果表明该模型预测的结垢堵塞物组成和堵塞程度与现场相符,对气井井筒除垢解堵措施具有指导意义。

In order to improve the pertinence of gas well plugging removal measures,the thermodynamic and dynamic effects of inorganic scaling in gas well wellbore were comprehensively considered,and the change of gas well water production and the adhesion coefficient of scaling on the inner wall of well wellbore were considered.The prediction model of gas well wellbore scaling and plugging was established and applied to Sulige gas field.The results showed that the longer the prediction time,the smaller the error of cumulative water production.The smaller the weighting coefficientα,the more accurate the prediction results.In the model,αwas taken as 0.2.Through the fitting of field production data,when the adhesion coefficient of scale on the inner wall of the wellbore was 0.001,a more satisfactory prediction result can be obtained.The field application results showed that the composition and blockage degree of scaling and blockage predicted by the model were consistent with the field,which had guiding significance for the measures of scale removal and blockage removal in gas well bore.