油基水泥浆在碳酸盐岩裂缝中的流动规律研究与应用

发布时间：2018-08-03 09:03

【摘要】：通过对油基水泥浆的组成、堵水机理以及流动规律的研究分析,建立了在柴油基前置液保护下油基水泥浆在碳酸盐岩裂缝中流动的数学模型,使用数学模型对最大流动深度与粘度、缝宽、压差以及注浆速度等因素的关系进行描述。通过室内研究对油基水泥浆体系的组成进行优化,同时考虑浆体沉降稳定性与流动性,得到置换效率为77.76%、表观粘度为1550mPa·s的普通油基水泥浆体系以及置换效率为51.29%、表观粘度为456mPa·s的油基超细水泥浆体系。通过在普通油基水泥浆中加入丙三醇提高浆体的水化深度,以便提高堵剂的利用率,实验证明加入水泥质量0.2%的丙三醇,可以将水化深度提高50%,并且对粘度与置换效率影响较小。对油基水泥浆在裂缝中的流动规律进行了室内物模实验,实验方案使用天然大理石板模拟碳酸盐岩裂缝,向模拟裂缝中泵入油基水泥浆来模拟浆体在裂缝中的流动情况,通过对物理模型中水泥浆流动规律的研究,结合数学模型,得到以下结果:遇水前,油基水泥浆在裂缝中的流动阻力并不高,而对比普通油基水泥浆,油基超细水泥浆在裂缝中的流动情况更好,流动阻力更低;遇水后,浆体在裂缝中的流动阻力迅速增大,在遇水初期,油基超细水泥浆的流动阻力依旧要低于普通油基水泥浆,但是,由于超细水泥水化速度比普通水泥更快,油基超细水泥浆流动阻力上更加迅速,常温下,在大约15min时,其流动阻力超过普通油基水泥浆。
[Abstract]:A mathematical model of oil-based cement slurry flowing in carbonate fractures under the protection of diesel-based preliquid is established by studying the composition of oil-base cement slurry, water shutoff mechanism and flow law. The relationship between maximum flow depth and viscosity, crack width, pressure difference and grouting speed is described by mathematical model. The composition of oil-base cement slurry system is optimized through laboratory study, and the stability and fluidity of slurry settlement are considered. The displacement efficiency is 77.76, the apparent viscosity is 1550mPa s, and the displacement efficiency is 51.29 and the apparent viscosity is 456mPa s. The hydration depth of the slurry was improved by adding glycerol to the ordinary oil-based cement slurry in order to improve the utilization ratio of the plugging agent. It was proved by the experiment that the cement was added with 0.2% glycerol by mass. The hydration depth can be increased by 50% and has little effect on viscosity and displacement efficiency. The flow pattern of oil based cement slurry in the fracture is studied in laboratory. The natural Dali stone slab is used to simulate the carbonate rock fracture, and the oil based cement slurry is pumped into the simulated fracture to simulate the flow of the slurry in the fracture. Through the study of the flow law of cement slurry in the physical model and combined with the mathematical model, the following results are obtained: the flow resistance of oil based cement slurry in fracture is not high before water treatment, but compared with that of ordinary oil based cement slurry, The flow resistance of the oil based ultrafine cement slurry in the fracture is better and the flow resistance is lower than that of the ordinary oil based cement slurry, and the flow resistance of the oil based superfine cement slurry in the early stage of water treatment is still lower than that of the ordinary oil based cement slurry. However, because the hydration speed of ultrafine cement is faster than that of ordinary cement, the flow resistance of oil based superfine cement slurry is faster than that of ordinary oil based cement slurry. At room temperature, at about 15min, the flow resistance of oil based superfine cement slurry is higher than that of ordinary oil based cement slurry.
【学位授予单位】：中国石油大学(华东)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE256

【参考文献】