CO_(2)地质利用与封存(CO_(2) geological utilization and storage,CGUS)是实现“碳中和”目标的重要技术手段,解决CGUS过程中的钢材腐蚀问题对于降低CGUS技术风险、实现CGUS技术规模化推广应用至关重要。综述了目前已经提出的CO_(2)...CO_(2)地质利用与封存(CO_(2) geological utilization and storage,CGUS)是实现“碳中和”目标的重要技术手段,解决CGUS过程中的钢材腐蚀问题对于降低CGUS技术风险、实现CGUS技术规模化推广应用至关重要。综述了目前已经提出的CO_(2)腐蚀钢材反应机制,总结了CO_(2)腐蚀钢材的主要影响因素,阐明了CO_(2)分压、温度、矿化度及pH值、CO_(2)封存环境中含有杂质、流体流动等因素对钢材腐蚀行为的影响,归纳了适用于CO_(2)腐蚀钢材防护的主要措施。基于此,提出了CGUS环境下钢材遭受CO_(2)腐蚀问题的重点研究方向。主要包括:CO_(2)腐蚀钢材反应机制的进一步探究;各项环境因素耦合作用影响CO_(2)腐蚀规律和腐蚀程度的量化研究;高浓度CO_(2)条件下腐蚀防护技术的开发与应用。展开更多
In order to improve CO_(2) capture,utilization and storage(CCUS) to solve carbon emission,sandstone from the Triassic Liujiagou Formation(LF) from the Ordos Basin in China was investigated using permeability tests and...In order to improve CO_(2) capture,utilization and storage(CCUS) to solve carbon emission,sandstone from the Triassic Liujiagou Formation(LF) from the Ordos Basin in China was investigated using permeability tests and computed X-ray tomography(CT) scanning.The presence of reactive minerals within the geological CO_(2) sequestration target storage formation can allow reaction with injected CO_(2),which changes the porosity and permeability of the LF beds,affecting storage effectiveness.To investigate the effect of chemical reactions on the pore structure and permeability of sandstone cores representing the LF CO_(2) storage,tests were conducted to analyze the changes in porosity and permeability of sandstone cores induced by CO_(2)-saturated brine at different reaction times(28-day maximum reaction period).Porosity and permeability of the sandstone increased after reaction with CO_(2)-saturated brine due to mineral dissolution.The sandstone exhibited an increase in porosity and permeability after 15 days of reaction with CO_(2)-saturated brine.Moreover,there was an increase in the volume of large pores in the sandstone after the 28-day period.The pore network of the sandstone was established through CT results,and the porosity calculated based on the obtained pore network was close to that measured in the test,demonstrating the feasibility to use CT to study the evolution of the microstructure of sandstone after long-time exposure to CO_(2)-saturated brine.展开更多
【目的】研究硅藻土对硅酸钠的吸附效果,探讨油井水泥环微裂缝的修复问题。【方法】采用硅酸钠作为自愈合剂,硅藻土为载体,利用真空浸渍法制备硅藻土基自愈合材料;借助扫描电子显微镜(scanning electron microscope,SEM)、红外光谱仪(in...【目的】研究硅藻土对硅酸钠的吸附效果,探讨油井水泥环微裂缝的修复问题。【方法】采用硅酸钠作为自愈合剂,硅藻土为载体,利用真空浸渍法制备硅藻土基自愈合材料;借助扫描电子显微镜(scanning electron microscope,SEM)、红外光谱仪(infrared spectrometer,FTIR)、全自动表面积和孔结构分析仪(automatic surface area and pore structure analyzer,BET)进行分析;通过对比分析掺入硅藻土基自愈合材料前、后水泥石的抗压强度、恢复率和渗透率等,对自愈合效果进行评价;通过对水泥石裂缝表面物质进行X射线衍射分析(X-ray diffraction,XRD)、热重分析(thermal analysis,TG)和SEM分析评价材料的自愈合机制。【结果】利用真空浸渍法能够成功制得硅藻土基自愈合材料;硅藻土基自愈合材料在油井水泥中最佳掺量为9%(质量分数),该试样劈裂造缝后自愈合14 d的抗压强度比纯水泥的提高99.57%,自愈合14 d后渗透率为0.42 mD,渗透率降低率达到75.44%,比纯水泥试样的高40.94%,且自愈合14 d后裂缝表面已经闭合。【结论】硅藻土基自愈合材料制备工艺简单,在油井水泥浆中具有良好的分散性和稳定性,可以促进油井水泥石微裂缝自愈合。展开更多
文摘CO_(2)地质利用与封存(CO_(2) geological utilization and storage,CGUS)是实现“碳中和”目标的重要技术手段,解决CGUS过程中的钢材腐蚀问题对于降低CGUS技术风险、实现CGUS技术规模化推广应用至关重要。综述了目前已经提出的CO_(2)腐蚀钢材反应机制,总结了CO_(2)腐蚀钢材的主要影响因素,阐明了CO_(2)分压、温度、矿化度及pH值、CO_(2)封存环境中含有杂质、流体流动等因素对钢材腐蚀行为的影响,归纳了适用于CO_(2)腐蚀钢材防护的主要措施。基于此,提出了CGUS环境下钢材遭受CO_(2)腐蚀问题的重点研究方向。主要包括:CO_(2)腐蚀钢材反应机制的进一步探究;各项环境因素耦合作用影响CO_(2)腐蚀规律和腐蚀程度的量化研究;高浓度CO_(2)条件下腐蚀防护技术的开发与应用。
文摘【目的】研究镁橄榄石掺加对减轻超临界CO_(2)环境下油井水泥石的腐蚀渗透性能。【方法】以镁橄榄石粉为外掺料配制不同的油井水泥,分析温度为150℃,CO_(2)总压为50 MPa条件下镁橄榄石水泥石的抗压强度,优选出镁橄榄石粉的最佳掺量;利用渗透率、热重分析(thermo gravimetric analysis,TGA)、X射线衍射(X-Ray diffraction,XRD)和扫描电子显微镜(scanning electron microscope,SEM)进行测试,评价镁橄榄石对油井水泥石抗CO_(2)腐蚀性能的影响,分析镁橄榄石对油井水泥石抗CO_(2)腐蚀的作用机制。【结果】镁橄榄石粉的掺入不会影响油井水泥的流动度,当镁橄榄石粉的质量分数为2%时,对比腐蚀前油井水泥石的,抗压强度提高35.47%,渗透率降低0.0104 m D;腐蚀28 d后,镁橄榄石水泥石的抗压强度为空白水泥石的193.71%,且仍高于腐蚀前。【结论】镁橄榄石是一种抗CO_(2)腐蚀外加剂,能提升油井水泥的抗CO_(2)腐蚀性能。
基金the funding support provided by the National Natural Science Foundation of China (Grant Nos. U1967208 and 42172315)。
文摘In order to improve CO_(2) capture,utilization and storage(CCUS) to solve carbon emission,sandstone from the Triassic Liujiagou Formation(LF) from the Ordos Basin in China was investigated using permeability tests and computed X-ray tomography(CT) scanning.The presence of reactive minerals within the geological CO_(2) sequestration target storage formation can allow reaction with injected CO_(2),which changes the porosity and permeability of the LF beds,affecting storage effectiveness.To investigate the effect of chemical reactions on the pore structure and permeability of sandstone cores representing the LF CO_(2) storage,tests were conducted to analyze the changes in porosity and permeability of sandstone cores induced by CO_(2)-saturated brine at different reaction times(28-day maximum reaction period).Porosity and permeability of the sandstone increased after reaction with CO_(2)-saturated brine due to mineral dissolution.The sandstone exhibited an increase in porosity and permeability after 15 days of reaction with CO_(2)-saturated brine.Moreover,there was an increase in the volume of large pores in the sandstone after the 28-day period.The pore network of the sandstone was established through CT results,and the porosity calculated based on the obtained pore network was close to that measured in the test,demonstrating the feasibility to use CT to study the evolution of the microstructure of sandstone after long-time exposure to CO_(2)-saturated brine.
