渤海A油田注水井压力上升原因及对策研究

渤海A油田注水开发过程中,注水井逐渐出现压力升高、注水不足现象。为此,在注入水水质及注入压力资料调研与分析的基础上,开展注水井堵塞机理研究,从注入水水质、结垢和腐蚀、配伍性分析以及微粒运移和出砂等方面,分析了注水压力上升原因,并针对此开展注水井解堵技术实验研究。结果表明,注入水中固悬物、粒径中值、含油量均超标,从而引起堵塞;溶解氧含量、总铁含量,细菌等均超标,导致注水过程中结垢和腐蚀管线,造成水井堵塞;复合酸体系7较好地解堵增油效果,可为A油田注水井的解堵增油提供可靠的技术保障。

Pressure rising and countermeasures analysis of water injectors in Bohai A oilfield

In the process of water flooding development in Bohai A oilfield, the phenomenon of rising pressure and insufficient injection gradually appeared. On the basis of investigation and analysis of the water quality and injection pressure data, the plugging mechanism of water injectors has been studied. The reasons for the pressure rising of injectors wellhead pressure were found out from the aspects of excessive water injection quality, scaling and corrosion leading to blockage, compatibility analysis, particle migration and sand production. And then, the experimental research on the plugging removal technique of water injectors was carried out. The results showed that the solids, median particle sizes and oil content in the injected water exceeded the standard, which caused blockage. Dissolved oxygen content, total iron content, bacteria and so on exceed the standard, resulting in scaling and corrosion pipeline in the process of water injection, leading to water injectors blockage. The compound acid system can effectively remove plugging and increase oil production, which can provide reliable technical support for the plugging removal and increase oil production in A oilfield.