基于井间干扰模型的气井压力恢复数值试井技术

Numerical build-up well test technology for gas wells based on inter-well interference model

传统的压力恢复试井解释难以正确甄别邻井的影响。为了认识井间干扰对压力恢复试井曲线的影响,将数值试井技术应用于压力恢复试井解释中,在测试前和测试中,基于不同的邻井工作制度建立相应的数值试井理论模型,得到邻井干扰引起的测试井压力恢复试井曲线的变化规律,并分析导致曲线变化的原因。研究表明在一口井进行试井测试时,邻井降低产量(或关井)会导致压力导数曲线上翘,与断层的压力恢复试井响应类似;邻井提高产量,会引起压力导数曲线下掉,与定压边界的压力恢复试井响应类似;为减小邻井干扰对测试井的影响,测试井进行压力恢复测试时,邻井应尽量保持原有的工作制度。该技术可为油气田开发提供更为准确可靠的依据。

Traditional build-up well tests cannot correctly identify the influence of offset wells.To understand how inter-well interference affects the build-up well test curve,the numerical well test technology was incorporated into the build-up well test.Before and during the test,specific numerical well test theoretical model was established depending on the working systems of offset wells,the variation of the build-up well test curve of the tested well caused by the interference from the offset wells was obtained,and the reasons for the curve change were analyzed.The results show that during well test of a well,the production decrease(or shut-in)of the offset well leads to upwarp of the pressure derivative curve,which is similar to the response of fault in build-up well test,and the production increase of the offset well causes the downwarp of the pressure derivative curve,which is similar to the response of the constant pressure boundary in build-up well test.To minimize the interference of the offset well to the tested well,it is recommended to keep the offset well working with original system when the build-up well test is conducted on the tested well.The proposed technology can provide a more accurate and reliable basis for oil and gas field development.