高含硫气井油压恢复曲线异常原因及校正方法

摘要

High sulfur gas reservoir wellhead often adopts pressure sensor to collect oil pres-sure,oil temperature and other data.After shut-in, the oil pressure recovery data can be an-alyzed to a certain extent. However, in the process of oil pressure recovery, the oil pressure recovery curve shows an abnormal decline, and the data of the bottom hole pressure can not be used for well test analysis. Aiming at this problem, the main reason for the abnormal oil pressure recovery curve of high sulfur gas well is the wellbore temperature. In the optimiza-tion of high sulfur gas deviation factor, on the basis of calculation and correction model based on Cullender&Smith method, considering the wellbore temperature profile nonlinear changes and the critical parameters, fixed high sour gas well gas is established considering the effects of wellbore heat transfer high sour gas well pressure buildup curve anomaly cor-rection model.Verified by the data of high sulfur gas well oil pressure recovery,the model is accurate and reliable.The results of this study have certain reference significance to the cal-culation of the bottom hole pressure and the correction of oil pressure recovery curve.%高含硫气藏气井常采用压力传感器采集油压、油温等数据,关井后的油压恢复资料在一定程度上可用于试井分析.但部分高含硫气井在油压恢复过程中,油压恢复曲线出现异常下降,折算的井底压力数据不能用于试井分析.针对这一难题,通过研究影响高含硫气井油压恢复曲线的原因,明确了导致高含硫气井油压恢复曲线异常的主要因素是井筒温度.在优选高含硫天然气的偏差系数计算及校正模型的基础上,基于Cullender&Smith方法,考虑井筒温度剖面非线性变化以及修正高含硫气井气体临界参数,建立了考虑井筒热传导影响的高含硫气井压力恢复曲线异常校正模型.利用高含硫气井油压恢复实测数据对该模型进行验证,表明该模型准确可靠.本研究成果对同类气井井底压力计算及油压恢复曲线校正具有一定的参考意义.