长井段水泥封窜技术研究

Research on Plugging Long Channel Wells with Cement

近几年发现长井段窜槽井较多 ,其主要原因是层间矛盾加大和高压层的存在。而以往各类化学封窜方法和封窜工艺由于工艺复杂、风险大等原因不能适应长井段封窜的需要。根据窜槽产生的原因和特点 ,利用水泥进行长井段封窜具有很多优势。针对长井段封窜的特点 ,选择超细水泥作为主料 ,对水泥配方进行了改进 ,主要是使其具有“直角稠化”的性能 ,并研制了防止地层漏失的桥塞剂。通过试验 ,确定了利用超细水泥进行长井段封窜的施工步骤。 2口井现场试验的经验说明 ,利用水泥进行长井段封窜成功的技术关键是带压侯凝。了解封窜井的吸入量与压力之间的规律 ,是下步做好长井段封窜工作的方向。

This paper presents a new method that the long channel is plugged with cement. With problems of zonal isolated interval and high pressure reservoir in Daqing Oilfield in latest years, there are a lot of channel wells. Furthermore, the conventional chemical treatment of channel wells can not meet the need of plugging long channel.According to the characteristics of plugging long channel wells, the cement formulation is improved and the bridge sealing agent is developed to prevent the thief zone.The treatment process is determined by using ultrafine cement to plug channel through the test.The field test shows that there are much more advantages to use cement at long channel in two wells and the waiting on cement with higher pressure is the key for sealing off long channel.