摘要
中原油田的白庙、河岸、文东和卫城等地区存在着大段易分散、膨胀的泥页岩.造成井下事故。为此.研制了高钙盐钻井液体系。室内实验结果表明,高钙盐钻井液体系能抗150℃以上高温,具有良好的流变性和较低的滤失量.滤饼韧性好;具有和饱和盐水相当的强抑制性,抗盐膏;具有较好的保护油气层作用。现场应用表明,高钙盐钻井液达到了:①固相容量限高,抑制性强,在密度为1.4 g/cm3、膨润土含量为43 g/L的情况下仍保持低粘度和切力;②机械钻速比邻井提高30％左右;③维护处理简单,处理成本低;④使用密度比邻井低0.05 g/cm3,保护油气层效果好,静态和动态岩心渗透率恢复值都大于80％。高钙盐钻井液较好地保护了油气层,成功地解决了泥页岩膨胀分散和垮塌问题。
In such areas as Baimiao, Hean, Wendong and Weicheng in Zhongyuan Oilfield, large section of dispersing and inflating shale exists and often causes downhole troubles, and the high calcium salt drilling fluid is developed to solve this problem. Laboratory testing results showed that this system has a temperature tolerance of over 150℃, and it has good rheology, low filtration and tough filtrate cake; it has strong inhibition comparable of the saturated saltwater, and good salt resistance. Field using displayed the following remarkable effects: 1. limited solids content and strong inhibition, it maintained low viscosity and shearing force when the density was 1. 4 g/cm3 and bentonite content was 43 g/L; 2. ROP improved by 30% than the offset well; 3. easy field maintenance and low treating cost; 4. the density is 0. 05 g/cm3 lower while better formation protection results were achieved, with both the dynamic and static core permeability higher than 80%.
出处
《钻井液与完井液》
CAS
北大核心
2002年第6期67-70,共4页
Drilling Fluid & Completion Fluid
