CT扫描技术在二氧化碳地质利用与封存领域的应用研究综述

二氧化碳储层岩石的孔隙率、渗透率及流体饱和度等是评价二氧化碳在地下储层中运移特性的主要参数,准确预测二氧化碳注入储层后的运移路径分布和运移范围,对于评价二氧化碳地质封存风险具有重大指导意义。以分析CT扫描技术在研究岩样孔隙结构、CO_2运移特征及水岩化学反应过程的应用现状和发展趋势为目的,在简要介绍CT扫描技术原理的基础上,通过对大量国内外文献的研究分析,综述了CT扫描技术在二氧化碳地质利用与封存领域的研究成果,并指出目前CT扫描技术的局限性及未来研究方向。分析表明,CT扫描技术在石油开发、地球科学等领域均有广泛应用。在二氧化碳地质利用与封存领域,该技术可以对储层岩石的三维孔隙结构进行表征,对储层岩石中流体的运移参数进行测定,并可获取岩心的三维矿物分布。目前采用CT扫描技术对原位条件下岩心的动态化学反应过程进行实时检测的研究还较少,此外,CT扫描图像不可避免地存在噪声及伪影,对试验结果产生影响。因此,搭建原位条件下分析岩心化学反应全过程的CT实时扫描系统,结合计算机领域先进的扫描图像降噪及去伪影技术,捕捉反应过程中岩心的微观变化,将是该领域未来的热点研究方向,可为二氧化碳地质封存风险评估提供技术支持。

Review on applications of CT scanning technique in the field of CO2 geological utilization and storage

Reservoir porosity, permeability and CO saturation are main characteristic parameters to evaluate CO migration behavior in the reservoir. Ac curate prediction of migration path and migration range after CO injection into reservoirs is very important to evaluate the risk associated with CO geologic sequestration.By taking the analysis on the status quo and development trend of the application of CT scanning technology to the researches of the pore str ucture of rock specimen, CO migration characteristics and CO water-rock chemical reaction process as the study objective, the study achievements obtain ed in the field of the application of CT scanning technology to CO geological utilization and storage are reviewed herein through the study and analysis on l arge amount of relevant literatures at home and abroad on the basis of brief description of the technical principle of CT scanning technology, while the limitation and the future study trend of CT scanning technology are pointed out as well. The analysis shows that the application of CT scanning technology is widel y in the fields of petroleum development, earth-science, etc. In the field of CO2 geological utilization and storage(CGUS), this technology can characterize th e 3-D pore structure of reservoir rock, determine the fluid migration parameters in reservoir rock and acquire the 3-D mineral distribution in the rock core. At present, the studies made on the real-time detection of the in-situ dynamic chemical reaction process of the rock core with CT scanning technology are less, while the inevitable noises and artifacts in CT scanning image can impact the relevant test result. Therefore, the future direction of the research hotspot is to construct a real-time CT scanning system for analyzing the entire process of the rock core chemical reaction under in-situ condition and capture the microsc opic change of the rock core during the reaction process in combination with the advanced noise reduction and artifact removal techniques in the field of co mputer, which can provide technical support for the risk assessment on CO2 geological storage.