矿渣可固化堵漏液的碱激发硬化特性研究及应用

发布时间：2018-01-20 01:10

本文关键词： 堵漏矿渣水化机理固化激发剂　出处：《西南石油大学》2017年博士论文　论文类型：学位论文

【摘要】：海相地层地质情况复杂,存在断层发育、地层破碎严重、压力窗口窄等特点。在钻完井过程中,当钻井液和水泥浆的密度大、黏度高时,时常发生井漏。目前堵漏剂种类较为单一,存在桥塞堵漏剂与漏层不匹配、高失水堵漏剂稳定性差、化学堵漏剂昂贵和膨胀时间难控制、水泥浆堵漏与钻井液相容性差,且存在施工不便等问题。本文旨在开发一种适用于裂缝发育地层高效堵漏技术,探寻堵漏液水化与硬化机理,为其工程应用设计奠定理论基础,主要从以下几方面进行研究:(1)固化剂选用冶金工业废料粒化高炉矿渣,利用其潜在凝胶特性实现堵漏液的硬化。矿渣组分、结构是研究水化反应的基础,综合运用X射线衍射、核磁共振、高清透射电镜、光电子能谱等分析手段,对其组分与结构进行分析表征。研究表明:矿渣组分是以非晶相为主,夹杂着一定量的微晶,同时含有少量CaO、SiO2及各种硅铝酸盐晶体的混合物;矿渣中的Si主要以硅氧四面体的形式存在,在空间结构上以正硅酸、焦硅酸为主及少量的架状结构形式存在;一部分Al以四配位的形式存在,一部分Al以五配位的形式存在,更多的Al以六配位的形式存在;O大部分以桥氧形式存在,少部分O以非桥氧的形式存在。(2)堵漏液的流变性直接影响其在漏层中流动阻力,本文通过测试基浆流动性与组分对流变参数影响,研究激发剂对流变性的作用机理。研究表明:浆体中固相粒子的浓度、膨润土加量、高分子材料加量改变,可导致浆体流动性能变化,依据其影响特征可实现对浆体的流变性调节。(3)堵漏成功的关键是形成一个段塞,有效阻止井内压力向裂缝尖端传递。矿渣材料的硬化需要碱金属化合物的激发,由于不同碱性介质对矿渣材料的激发效能不同,须通过水化硬化机理研究;弄清矿渣材料矿物组分、结构与激发剂之间的物理化学作用特性,评价出影响因素和反应特征,才能为固化体应用性能设计提供技术途径与理论指导依据。研究表明:Na2SiO3·9H2O、NaOH、Na2CO3激发效果由高到低;碱激发矿渣本质是使一部分焦硅酸的Si-O键断裂,转变为正硅酸,矿渣中[SiO4]4-聚合度越低的结构比例越多,固化体强度越高;Na2CO3、Na2SiO3·9H2O由于水解产生的OH-浓度较低,除使Si-O键断裂,还会使聚合度增加;养护温度升高,碱激发矿渣水化产物的结构,未发现明显的变化。(4)使用单一碱性化合物对矿渣进行激发时,存在低温条件下激发效果不好、固化体早期强度低的问题。依托水化反应热力学特征讨论了激发剂对硬化体水化特性的影响,以确定激发剂复配原则。研究结果表明:要实现堵漏液体系在3℃养护强度较好发展,激发剂中OH-浓度在整个反应过程中维持在一定水平,且当激发剂可提供[SiO4]4-时,激发效果更好。(5)矿渣固化体高温养护容易开裂,阻碍了其作为结构材料的广泛应用性。为研究矿渣固化体的结构和受力,借助Micro-CT无损检测等手段,深入探讨矿物组分微观结构、水化反应过程、水化产物微观结构,对固化体开裂原因进行了分析。研究发现:矿渣水化产物中易开裂的矿物组分和交变热应力可诱导固化体产生微裂缝;在浆体配制过程中引入的空气,促使了裂缝进一步的延伸。(6)为使该体系适应不同井深的需要,研究了不同密度堵漏液强度发展规律。结果表明:采用三种激发剂复配的方式进行激发,可使低密度体系在低温条件下有较好的早期强度;体系中胶凝相含量较高、温度较高时,采用单一激发剂进行激发效果较好。(7)研究成果在川东北重庆气矿等严重漏失井中成功进行了工业试验,提高了堵漏效能、减少了作业次数、节约了钻井液与水泥浆消耗量,降低了堵漏作业成本,形成了一项堵漏新技术。矿渣作为建材辅料主要用于生产建筑用高强特殊水泥,配制低水化热大坝水泥防止硬化开裂,对废弃钻井液进行地面固化处理,但都属于低温应用环境。国内外在上世纪九十年代曾尝试过MTC固井技术,但由于1.3g/cm3体系强度不足、高温养护固化体容易开裂、难以替代水泥材料,导致该新技术“昙花一现”。本文研究内容将为矿渣材料自凝结、钻井液凝结、环空泥饼和顶替窜槽混合物一体化凝结技术的研发,展现出广阔的应用前景。
[Abstract]:The marine strata in complex geological conditions, there are serious faults, strata broken, narrow pressure window. In the drilling process, the drilling fluid and cement slurry density, high viscosity, often well leakage. At present the plugging agent type is relatively single, existing bridge plug plugging agent and leakage layer does not match the high water loss plugging agent has poor stability, chemical plugging agent is expensive and difficult to control the time of expansion, cement slurry and drilling fluid compatibility is poor, and there is construction inconvenience and other issues. This paper aims to develop a high efficient plugging technology for strata cracks, explore the plugging fluid hydration and hardening mechanism, lay a theoretical foundation for its application in engineering design. The main study from the following aspects: (1) the curing agent adopts metallurgical industrial waste granulated blast furnace slag, hardening of the plugging fluid by its potential. The gel properties of slag component, the structure is the base of hydration Further, the integrated use of X ray diffraction, NMR, HD TEM, XPS analysis method, analysis and characterization. The composition and structure of research shows that the slag component is in amorphous phase, with a certain amount of ceramics, also contains a small amount of CaO, a mixture of SiO2 and various siliconaluminatecrystal the slag; Si mainly exists in the form of silicon oxygen tetrahedron, the space structure of the Tetraethyl silicate mainly exists, coke and a small amount of frame structure form; a part of the Al in four coordinated, part of the Al in five coordinated, more Al in the form of six coordination; most of the O in bridge oxygen form a small part of O exists in the form of non bridging oxygen. (2) the rheology of plugging fluid directly influences the flow in the drain layer resistance, the influence on the rheological parameters through the test of slurry fluidity and convection of activator group. The mechanism of degeneration. The study shows that the concentration of solid particles in the slurry, bentonite dosage, polymer dosage changes can lead to changes of slurry flow properties, on the basis of the impact characteristics can be realized on the rheology of slurry regulation. (3) the key to success is to form a sealing plug. Effectively prevent well pressure transfer to the crack tip. The hardening slag material to stimulate alkali metal compounds, because of different alkaline medium on activated slag material performance required by the different hydration mechanism of slag material; clarify mineral composition, physical and chemical properties between structure and activator, evaluation factors and reaction the characteristics, in order to provide technical basis and theoretical guidance for the design approach of solidified body application performance. The study shows that Na2SiO3, 9H2O, NaOH, Na2CO3 excitation effect from high to low; alkali activated slag is a part of disilicate The rupture of the Si-O bond into silicate, [SiO4]4- polymerization degree is low and the more proportion of slag, the strength of the solidified body is higher; Na2CO3, Na2SiO3 and 9H2O due to the concentration of OH- from hydrolysis is relatively low, except that Si-O bond rupture, will make the increase of the degree of polymerization; the higher curing temperature, the structure of alkali activated slag hydration the product, without obvious change. (4) using a single alkali compound excitation of slag, low temperature under the condition of excitation effect is not good, the early strength of the solidified body. Based on the hydration thermodynamics characteristics discussed the effects of activator on the hydration properties of the hardened body, to determine the principles of compound activator. The results show that: to achieve better development system of plugging liquid at 3 DEG C curing strength, OH- concentration of activator in the whole reaction process maintained at a certain level, and when the activator can provide [SiO4]4-, stimulate the better. (5) solid slag Body temperature maintenance is easy to crack, has hindered its wide application as structural material. As the structure of the slag solidified body and stress, with the help of Micro-CT nondestructive testing methods, in-depth study of mineral composition microstructure, hydration process, hydration products on the microstructure, cracking of solidified body were analyzed. The study found: slag hydration products and easy cracking of mineral components and alternating thermal stress can induce the solidified body to produce micro cracks; introduced in the slurry preparation process in the air, the crack further extended. (6) to enable the system to meet the needs of different depth, studied different density the liquid leakage intensity. The results showed that: the three kinds of compound activator to stimulate, the low density system has higher early strength under low temperature conditions; high cementitious content system, when the temperature is high, with a single excitation Agent for better results. (7) research in Northeast Sichuan gas mine of Chongqing and other serious leakage wells successfully conducted industrial test, improve the plugging efficiency, reduce operation times, save the drilling fluid and cement slurry consumption, reduce the cost of plugging, the formation of a new technology of slag plugging. As the building materials mainly used for the production of special cement building with high strength, low heat of hydration of cement mixed dam to prevent the hardening of surface cracking, solidification of the waste drilling fluid, but belongs to the low temperature application environment at home and abroad. In 90s have tried MTC cementing techniques, but because the 1.3g/cm3 system of insufficient strength, high temperature curing solidified body is easy to crack it is difficult to replace, cement materials, leading to the new technology. The research content of this paper will flower briefly as the broad-leaved epiphyllum "for slag material self condensation, condensation of drilling fluid, annulus mud cake and replace channeling mixture The research and development of the body condensation technology shows a broad application prospect.

【学位授予单位】：西南石油大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TE52

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