Iloejesi Chidera O, Beckingham Lauren E
Department of Civil Engineering, Auburn University, Auburn, Alabama, USA.
Environ Eng Sci. 2021 Mar 1;38(3):115-126. doi: 10.1089/ees.2020.0345. Epub 2021 Mar 17.
Compressed energy storage (CES) of air, CO, or H in porous formations is a promising means of energy storage to abate the intermittency of renewable energy production. During operation, gas is injected during times of excess energy production and extracted during excess demands to drive turbines. Storage in saline aquifers using CO as a cushion or working gas has numerous advantages over typical air storage in caverns. However, interactions between CO and saline aquifers may result in potential operational limitations and have not been considered. This work utilizes reactive transport simulations to evaluate the geochemical reactions that occur during injection and extraction operational cycles for CES in a porous formation using CO as a cushion gas. Simulation results are compared with similar simulations considering an injection-only flow regime of geologic CO storage. Once injected, CO creates conditions favorable for dissolution of carbonate and aluminosilicate minerals. However, the dissolution extent is limited in the cyclic flow regime where significantly smaller dissolution occurs after the first cycle such that CO is a viable choice of cushion gas. In the injection-only flow regime, larger extents of dissolution occur as the fluid continues to be undersaturated with respect to formation minerals throughout the study period and porosity increased uniformly from 24.84% to 33.6% throughout the simulation domain. For the cyclic flow conditions, porosity increases nonuniformly to 31.1% and 25.8% closest and furthest from the injection well, respectively.
在多孔地层中对空气、一氧化碳或氢气进行压缩能量存储（CES）是一种很有前景的能量存储方式，可缓解可再生能源生产的间歇性问题。在运行过程中，在能源生产过剩时注入气体，在需求过剩时提取气体以驱动涡轮机。使用一氧化碳作为缓冲或工作气体存储在盐水层中比在洞穴中进行典型的空气存储具有许多优势。然而，一氧化碳与盐水层之间的相互作用可能会导致潜在的运行限制，目前尚未得到考虑。这项工作利用反应输运模拟来评估在多孔地层中以一氧化碳作为缓冲气体进行压缩能量存储的注入和提取操作循环期间发生的地球化学反应。将模拟结果与考虑地质一氧化碳存储仅注入流态的类似模拟进行比较。一旦注入，一氧化碳会创造有利于碳酸盐和铝硅酸盐矿物溶解的条件。然而，在循环流态中溶解程度是有限的，在第一个循环之后溶解量显著减小，因此一氧化碳是一种可行的缓冲气体选择。在仅注入流态中，随着流体在整个研究期间相对于地层矿物持续不饱和，溶解程度更大，并且在整个模拟区域内孔隙度从24.84%均匀增加到33.6%。对于循环流条件，孔隙度在距离注入井最近和最远的地方分别不均匀地增加到31.1%和25.8%。
