一种可替代甲酸盐钻井液的改型甲酸盐钻井液的应用研究

Research on the Application of Modified Formate Drilling Fluid

辽河油田潜山井段钻井过程中存在严重的井漏问题,个别井漏失近2000m3,造成高成本甲酸盐钻井液的极大浪费。为节省钻井投资,达到资源循环利用的目的,采用玉米生化法制乙二醇、丙二醇的副产物开展可替代甲酸盐钻井液的改型甲酸盐钻井液的研究与推广应用工作。通过基浆的配制以及流型调节剂、提黏剂、降滤失剂、润滑剂、暂堵剂的选择与加量等相关评价实验研究,最终确定改型甲酸盐钻井液基本配方为:自来水+50%改型甲酸盐+0.2%XC+0.3%PAC+0.7%SMP-Ⅱ+0.7%KH-931+2.5%石墨+3%超低渗透剂。通过室内评价,形成了电阻率0.86Ω·m、润滑系数0.048、腐蚀速率0.000387mm/a、抗土粉污染能力好、成本相对较低的改型甲酸盐钻井液体系。现场应用结果表明,本研究所获得的改型甲酸盐钻井液能够满足潜山油藏钻井施工需要,单井节约钻井成本38.4万元。

Severe lost circulation is appearing in drilling of the buried hill interval in Liaohe oilfield,and individual lost circulation is nearly 2000m3,which results in great waste of the high-cost formate drilling flu- id.In order to save drilling investment and achieve the aim of circular using of resource ,maize biochemistry is applied to the development of byproduct of the ethylene glycol and propylene glycol.The modified formate drilling fluid is researched and applied for popularization.After the correlated assessment experimental research on the preparation of basic mud and selection and dosage of flow pattern correctives ,viscosity raising agent, filtrate reducer,lubricant and temporary plugging agent,the basic recipe of the modified formate drilling fluid is fixed at last：tap water＋50% modified formate＋0.2%XC＋0.3%PAC＋0.7%SMP-Ⅱ ＋0.7%KH-931 ＋2.5% graphite＋3% super-low permeability agent.After laboratory evaluation,the modified formate drilling fluid system is formed with 0.86Ωm of electrical resistivity,0.048 of lubrication coefficient,0.000387mm/a of corrosion rate ,good capability of anti-pollution of bentonite and relative low cost.Field application result shows that the new modified formate drilling fluid can meet the demands of drilling operation in the buried hill reservoirs and drilling cost of single well saved 384 thousand yuan