玄武岩二氧化碳矿化封存(I):技术特点及适用条件  

CO_(2)mineral storage in basalt(I):Technology and application conditions

作　　者：周蒂 夏菖佑[1] 李鹏春 梁希 ZHOU Di;XIA Changyou;LI Pengchun;LIANG Xi(UK-China(Guangdong)CCUS Centre,Guangzhou 510440,China;Key Laboratory of Ocean and Marginal Sea Geology,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou 510301,China;University College London,London WC1E 6BT,United Kingdom)

机构地区：[1]中英(广东)CCUS中心,广州510440 [2]中国科学院南海海洋研究所,边缘海与大洋地质重点实验室,广州510301 [3]伦敦大学学院,伦敦WC1E 6BT

出　　处：《环境工程学报》2024年第10期2708-2718,共11页Chinese Journal of Environmental Engineering

基　　金：广东省基础与应用基础研究基金(2021A1515011298);国家重点研发计划资助项目(2021YFF0501202)。

摘　　要：玄武岩CO_(2)矿化封存作为玄武岩发育区开展碳捕集利用与封存(CCUS)的有效途径,其可行性已得到美国Wallula项目和冰岛Carbfix项目的验证。在碳中和目标下,玄武岩CO_(2)矿化封存技术也引起了我国的广泛关注,并进行了若干可行性研究,但迄今国内尚缺乏对该技术的系统性报道和详细分析,对2种技术的特点和适用条件在认识上存在漏洞和误区,需要弥补和澄清。现有资料表明,Wallula技术向玄武岩储层注入超临界CO_(2),可视为咸水层碳封存技术向玄武岩的应用延伸,其技术成熟度高,但要求储层深度大于800 m且具备有效盖层。而Carbfix技术是模仿并加速自然界玄武岩的风化过程,向玄武岩储层注入CO_(2)水溶液,要求所注入的水溶液在储层状态下保持CO_(2)欠饱和状态,CO_(2)以溶解相或矿化相封存,不出现游离态CO_(2),因而不存在泄漏风险,无需盖层即可达到高安全性。该技术并不要求储层深度大于800 m,但要求储层深度不小于潜水位以下约250 m,以达到CO_(2)封存容量与注水量的最佳平衡。两种技术相比,Wallula技术可能实现较大的单井注入速度和封存容量,但成本较高,比较适合于在玄武岩区开展大规模碳封存,通过规模效应来降低成本;或在含玄武岩的沉积盆地与沉积岩碳封存合并进行。而Carbfix技术成本较低,可以利用较浅的或无盖层的玄武岩储层,但单井封存量有限,所需注水量较大,比较适合于近排放源小规模碳封存,或通过多井集群化来实现的较大规模的碳封存。CO_(2)mineral storage in basalt(CMSB),as an effective approach for carbon capture,use and storage(CCUS)in basaltic regions,has been proven feasible through the Wallula project in the US and the Carbfix project in Iceland.In China,several feasibility studies on CMSB have been conducted.However,in China there is currently a lack of systematic and detailed reports on this technology,and existing gaps and misunderstandings on the details and application conditions of the two technologies need to be clarified.According to existing information,the Wallula technology involves the injection of supercritical CO_(2)into basaltic reservoirs,effectively transplanting carbon storage technology from sedimentary rocks to basalts.While this method is technologically mature,it requires reservoir depths greater than 800 meters and the presence of effective caprocks.In contrast,the Carbfix technology seeks to emulate and accelerate natural basalt weathering processes by injecting CO_(2)solution into basaltic reservoirs.The injected solution is kept below CO_(2)solubility at reservoir conditions to avoid potential degassing.Thus,within the reservoir CO_(2)is stored only in soluble and mineralized forms,virtually eliminating the risk of leakage,and thereby eliminating the need for caprocks.The Carbfix technology does not require the reservoir depths greater than 800 m.However,it requires the reservoir depths greater than 250 m below the local water level in order to obtain optimal balance between storage capacity and the quantity of injected water.In comparison,the Wallula technology may achieve high-rate and large-capacity single-well storage,but with higher cost.It would be suitable for largescale projects in basaltic areas to reduce the cost through scale-effect.While the Carbfix technology has broader applicability and lower cost,but limited single-well storage capacity and requires substantial water supply.Thus it favorites nearsourced small-scaled storage,or larger-scaled storage though clusters of multiple injection wells.

关 键 词：玄武岩CO_(2)矿化封存 碳捕集利用与封存(CCUS) 碳封存技术 超临界态CO_(2)注入技术 溶解态CO_(2)注入技术 Wallula技术 Carbfix技术 

分 类 号：X511[环境科学与工程—环境工程]