W433区块分层压力测试技术

Layered pressure testing technology in block W433

W433区块已进入中含水开发阶段,随着注水时间的增加,油藏压力逐步升高,各小层间的差异逐年增大,合层压力测试已经不能满足精细开发的需要。在该区块西部和西南部优选出层间矛盾突出,液量、含水变化明显,小层之间距离较远、井况较好的井进行分层压力测试。两层同时生产一段时间后,利用井下开关井器,逐层进行关井压力恢复。第一层测试时,另外一层不停产。结果表明,各小层之间的压力分布不均,层间压差分布在0.94~9.13 MPa之间,层间矛盾明显。针对测试结果,在整个区块开展酸化解堵、分层隔采、周期轮注、同心双管分注等治理措施,油井含水上升率降至1.7%,阶段自然递减率降至7.1%。该技术一次测试可得到多层油藏参数,减少了测试期间的产量损失,具有良好的应用前景。

The block W433 has entered the development stage of medium water cut.With the increase of water injection time,the reservoir pressure gradually increases,and the production difference between each small layer is increasing year by year.The combined layer pressure test cannot meet the needs of fine development.In the west and southwest of the block,the wells with prominent interlayer contradictions,obvious changes in liquid volume and water cut,long distance between small layers and good well condition,are selected for layered pressure test.After a period of simultaneous production of the two layers,the shut-in pressure is record layer by layer by using the downhole well switch.When the first layer is tested,the other layer does not stop production.The results show that the pressure distribution between the layers is uneven,the pressure difference between the layers is between 0.94 MPa and 9.13 MPa,and the contradiction between the layers is obvious.According to the test results,acidizing and plug removal,separate zone production,periodic rotation injection and concentric double pipe separate injection were carried out in the whole block.The water cut rise rate of oil well was reduced to 1.7%,and the natural decline rate of oil well was reduced to 7.1%.This technology can get multi-layer reservoir parameters in one test,reduce the production loss during the test,and has a good application prospect.