Remediation of Set Cement in Heavy Oil Thermal Production Wells with CO2 under Cumulative Working Conditions
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摘要: 根据稠油火烧水泥石在井下先经历蒸汽吞吐、蒸汽驱，再经历稠油火烧的实际工况，利用超高温水泥石养护装置及高温高压腐蚀釜，研究累积工况下CO2对水泥石抗压强度及腐蚀深度的变化规律；同时，利用XRD和SEM等技术探明了CO2对水泥石化学结构及微观形貌的影响。实验结果表明，水泥石经常温及高温养护后呈现高孔渗、低强度的特征，但累积工况下经CO2腐蚀釜养护后，抗压强度不减反增，到28 d时已升至53.4 MPa，较蒸汽驱后提高了54.87%；而随着CO2腐蚀龄期的延长，水泥石腐蚀深度逐渐加深，结构更为致密，且28 d后已被完全碳化。究其原因，水泥石经CO2腐蚀后，腐蚀产物CaCO3溶解度较低，并在孔隙中沉淀结晶，堵塞毛细孔或将大孔分割成小孔，使水泥颗粒密实度提高。该研究结果可进一步丰富业界对CO2腐蚀的认识，同时也为稠油火烧水泥浆体系的性能评价、配方优化提供参考。Abstract: In heavy oil fire flooding, the downhole set cement was experiencing steam huff and puff and steam flooding at first, and then heavy oil in-situ combustion. Based on these actual working conditions, an ultra-high-temperature set cement curing device and high temperature high pressure corrosion test kettle were used to study the changing pattern of the compressive strength and corrosion depth of set cement affected by CO2 under cumulative working conditions. Also, XRD and SEM were used to investigate the effect of CO2 on the chemical structure and micromorphology of set cement. Experimental results showed that set cement after curing at normal and high temperatures has high porosity and permeability, and low strength. The same set cement, when curing in CO2 corrosion test kettle under cumulative working conditions, the compressive strength increases to the contrary; the compressive strength of the set cement was increased to 53.4 MPa when curing for 28 days, increasing by 54.87% compared with the compressive strength of the set cement after steam flooding. With the corrosion of the set cement by CO2 going on, the corrosion depth on the set cement was gradually deepened, and the structure of the set cement was becoming denser, and after 28 days the set cement was fully carbonized. The reason for this phenomenon is that the corrosion product CaCO3 has low solubility, it precipitates and crystalizes inside the pores in the set cement. The crystal plugs the capillaries in the set cement, or just divides the big pores into smaller pores, thereby increasing the packing density of the cement particles. The results of this study further enrich the industry’s understanding of CO2 corrosion, and also provide reference to the performance evaluation and composition optimization of the heavy oil in-situ combustion cement slurries.
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[1] LIU K, CHENG X, MA Y, et al. Analysis of interfacial nanostructure and interaction mechanisms between cellulose fibres and calcium silicate hydrates using experimental and molecular dynamics simulation data[J]. Applied Surface Science, 2020:506. [2] CAREY J W. Geochemistry of wellbore integrity in CO2 sequestration: Portland cement-steel-brine-CO2 interactions[J]. Reviews in Mineralogy and Geochemistry, 2013, 77:505-539. doi: 10.2138/rmg.2013.77.15 [3] LIAUDAT J, MARTíNEZ A, LóPEZ C M, et al. Modelling acid attack of oilwell cement exposed to carbonated brine[J]. International Journal of Greenhouse Gas Control, 2018, 68:191-202. doi: 10.1016/j.ijggc.2017.11.015 [4] 张明亮. 火烧油层工况下固井水泥材料及耐高温耐腐蚀性能研究[D]. 成都: 西南石油大学, 2017.ZHANG Mingliang. Study on cementing cement materials and high temperature and corrosion resistance under the condition of burning oil reservoir[D]. Chengdu: Southwest Petroleum University, 2017. [5] 程小伟,张明亮,李早元,等. 火烧油层工况下加砂油井水泥石失效演化研究[J]. 硅酸盐通报,2016,35(8):2335-2340.CHENG Xiaowei, ZHANG Mingliang, LI Zhaoyuan, et al. Study on the failure evolution of cement stone in sand adding oil well under the condition of burning oil reservoir[J]. Silicate Bulletin, 2016, 35(8):2335-2340. [6] HUANG S, CHEN X, LIU H, et al. Experimental and numerical study of steam-chamber evolution during solvent-enhanced steam flooding in thin heavy-oil reservoirs[J]. Journal of Petroleum Science and Engineering, 2019, 172:776-786. doi: 10.1016/j.petrol.2018.08.071 [7] HUANG S, CHEN X, LIU H, et al. Experimental and numerical study of solvent optimization during horizontal-well solvent-enhanced steam flooding in thin heavy-oil reservoirs[J]. Fuel, 2018, 228:379-389. doi: 10.1016/j.fuel.2018.05.001 [8] LYU X, LIU H, PANG Z, et al. Visualized study of thermochemistry assisted steam flooding to improve oil recovery in heavy oil reservoir with glass micromodels[J]. Fuel, 2018, 218:118-126. doi: 10.1016/j.fuel.2018.01.007 [9] SARIDEMIR M, SEVERCAN M H, ÇIFLIKLI M, et al. Microstructural analyses of high strength concretes containing metakaolin at high temperatures[J]. International Journal of Cilil Engineering, 2017, 15:273-285. [10] KATHIRVEL P, KWON S J, LEE H S, et al. Graphite ore tailings as partial replacement of sand in concrete[J]. ACI Materials Journal, 2018, 115(3):481-492. [11] 中国石油集团工程技术研究院. GB/T 19139—2012油井水泥试验方法[S]. 北京: 中国标准出版社, 2012.CNPC Engineering Technology Research Institute. Procedure for testing well cements[S]. Beijing: China Standard Press, 2012. [12] MASON H E, FRANE W, WALSH S, et al. Chemical and mechanical properties of wellbore cement altered by CO2-rich brine using a multianalytical approach[J]. Environmental Science & Technology, 2013, 47(3):1745-1752. [13] LESTI M, TIEMEYER C, PLANK J. CO2 stability of portland cement based well cementing systems for use on carbon capture & storage (CCS) wells[J]. Cement and Concrete Research, 2013, 45:45-54. doi: 10.1016/j.cemconres.2012.12.001 [14] 张亮,姚晓,罗霄,等. 提高油井水泥石抗CO2腐蚀外掺料的性能[J]. 石油钻探技术,2010,38(4):15-18.ZHANG Liang, YAO Xiao, LUO Xiao, et al. Improving the performance of oil well cement admixture resistant to CO2 Corrosion[J]. Petroleum Drilling Technology, 2010, 38(4):15-18. [15] 韩冀豫. 高掺量粉煤灰水泥水化产物C—S—H凝胶聚合程度的研究[D]. 武汉理工大学, 2011.HAN Jiyu. Study on the degree of C—S—H gel polymerization of hydration products of high content fly ash cement[D]. Wuhan University of Technology, 2011. [16] WIGAND M, KASZUBA J P, CAREY J, et al. Geochemical effects of CO2 sequestration on fractured wellbore cement at the cement/caprock interface[J]. Chemical Geology, 2010, 262(2):122-133. -
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