针对涠洲M油田注水开发过程中注水量下降、注水压力明显上升的现象,通过对该油田注水过程中潜在损害因素的分析,以及对储层岩性特征、物性特征及流体特征的分析研究,结合储层敏感性评价试验结果,提出了相应的油层保护对策.储层敏感性评价结果表明:储层临界流速为5 mL/min,为弱速敏;临界矿化度为5 964.5 mg/L,水敏损害程度为中等偏强至强水敏;临界pH值为11,储层具有中等偏弱碱敏;盐酸和土酸敏感性评价结果为无酸敏,说明该注水层段为可酸化处理储层.指出在油田后期注水开发过程中,应结合油田实际情况,采取一定的措施控制水敏、速敏等现象的发生;严格控制注入水水质指标;实施酸化增注措施前要进行酸液浓度及施工工艺的优选,为确保油田后期注水开发的顺利进行提供保障.%According to the phenomenon of the obvious increase of water injection pressure and the decrease of water injection in Weizhou M Oilfield,based on the analysis of potential damage factors,reservoir lithology,physical properties and fluid characteristics in the process of oilfield water injection,combined with the experimental results of reservoir sensitivity evaluation,the corresponding countermeasures for reservoir protection are proposed.The reservoir sensitivity evaluation results show that reservoir critical velocity is 5 mL/min,weak velocity sensitivity;critical salinity is 5 964.5 mg/L,with medium strength to strong water sensitivity;critical pH value is 11,the reservoir has moderate weak sensitivity.The results of the evaluation of hydrochloric acid and soil acid sensitivity are no acid sensitivity,indicating that the water injection layer is an acidified reservoir.It is pointed out that in the later stage of oilfield water flooding process,certain measures should be taken combined with the actual situation to control water sensitivity,velocity sensitivity and other phenomena;the water quality specifications should be strictly controlled;the acid concentration and the construction process should be optimized before the implementation of acidizing measures,which provide guarantee to ensure the smooth development of oil field water injection.
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