| Popis: |
For the characteristics of serious formation damage and insufficient injecting in injection wells in the water flooding development process in low permeability oilfield, it carries the analysis of reasons for forming low efficient injection wells and the development of acidizing disentanglement agent. Through core damage experiment of wellhead sewage in S oilfield, formation damage is mainly caused by excessive levels of suspended matters and the multiple of exceeding standards is 45.3. Based on the result of core damage experiment and actual oilfield production data, the variation of apparent injectivity index in low efficient injection wells is researched. The research result indicates that formation damage radius of pollution wells is about 20m in this oilfield. Based on formation damage condition of this oilfield, compound acid is developed, which has the properties of strong penetration, retarding reaction velocity and strong-chelating. Plug removal experiment indicates that the recovery rate of core permeability is about 100% using developed compound acid. |
