The geomicrobiology of hydrogen storage in geological materials

为了在地下推广英国氢储存，需要关于地质储存地点本身以及在这些地下环境中发生的氢-微生物相互作用的信息。主要在英国，储氢所需的地质构造是溶解洞穴（储存在盐矿中）或多孔介质中，例如含水层和枯竭的石油和天然气田（DOGF）。地下微生物过程、氢与岩石材料之间的化学和矿物学反应可能产生不需要的副产品（硫化氢、甲烷、生物堵塞），导致返回气体中的杂质或洞穴/储层异质性的变化。有已知的微生物（例如，产甲烷菌、硫还原菌、同型产乙酸菌），它们消耗氢作为能源，但不清楚它们的菌落如何相互作用/相互竞争，也不清楚在地下占主导地位的过程/机制。地下微生物过程的现有知识是有限的。对于大规模地下储氢，提出了三个领域：盐洞，枯竭的石油和天然气储层和盐水层。将开展实验工作，以了解氢微生物相互作用及其对储层矿物学地球化学反应性的影响。盐穴目前是全球大部分氢气和大部分天然气的储存地。随着氢气使用量的扩大，天然气储存量的扩大或转化为氢气的情况可能会发生。然而，关于盐穴中的微生物如何与氢气相互作用的研究有限。这是重要的，因为它可能降低氢气的产率和纯度，这可能导致需要额外成本的储存后纯化。多孔介质（DOGF和盐水层）对于绿色氢特别有利，其中盐穴存储在没有大规模管道基础设施的情况下不容易接近，但是地下储层就在附近（例如，离岸风产生绿色氢并直接储存到地下）。提供大量氢气的多孔介质与盐穴竞争，北海现有的管道网络可以重新利用/改装以输送氢气。通过北海石油和天然气行业的大量信息，已经对已知的孔隙度和渗透率条件进行了地质调查，这两个因素对于任何类型的多孔介质储气库都非常重要。将通过在NU-OMICS测序服务（Northumbria University）的Illumina MiSeq平台上进行的16s rRNA测序来确定微生物。将在氢微生物相互作用实验之前和之后进行岩相分析，以确定储层是否发生任何矿物学变化（例如，矿物溶解或沉淀）。如果时间允许，英国将在陆上和海上寻找潜在的地质储存地点。特别是寻找二叠纪和三叠纪盐矿床和咸水层和DOGF上的UKCS。

To rollout UK hydrogen storage in the subsurface, information is needed regarding the geological storage site itself and the hydrogen - microbe interactions that occur in these subsurface environments. Primarily in the UK, geological formations desired for hydrogen storage are caverns by dissolution (storage in salt deposits) or in porous media, such as aquifers and depleted oil and gas fields (DOGF). Subsurface microbial processes, chemical and mineralogical reactions between hydrogen and the rock material can produce unwanted by products (hydrogen sulphide, methane, bio clogging) leading to impurities in the returned gas or changes in cavern/reservoir heterogeneity. There are known microbes (e.g., methanogens, sulphur reducing bacteria, homoacetogens) that consume hydrogen as an energy source, but it is not clear how their colonies interact/compete with one another or the processes/mechanisms which dominate in the subsurface. Existing knowledge of subsurface microbial process is limited. For large scale underground hydrogen storage three areas are proposed: salt caverns, depleted oil and gas reservoirs and saline aquifers. Experimental work will be carried out to understand the hydrogen microbe interactions and their effects on the geochemical reactivity on reservoir mineralogy. Salt caverns currently act as storage for most of the hydrogen and a large proportion of natural gas globally. Either scaling up or converting natural gas stores to hydrogen is likely to happen as hydrogen usage expands. However, there are limited studies on how microbes in the salt caverns interact with the hydrogen gas. This is important as it could reduce both the yield and purity of hydrogen which could lead to post storage purification being required at additional costs. Porous media (DOGF and saline aquifers) are especially advantageous for green hydrogen where salt cavern storage is not easily accessible without large scale pipeline infrastructure, but subsurface reservoirs are nearby, (e.g., offshore wind to produce green hydrogen and straight to underground storage). Porous media offering huge volumes of hydrogen gas competed to salt caverns and an already existing pipeline network in the North Sea can be repurposed/refitted to deliver hydrogen. With ample information from the oil and gas industry in the North Sea, geology is already surveyed with known conditions of porosity and permeability, two factors hugely important for any type of porous media gas storage. Microorganisms will be determined through 16s rRNA sequencing conducted on Illumina MiSeq platform at the NU-OMICS sequencing service (Northumbria University). Petrographic analysis will be carried out before and after hydrogen microbial interaction experiments to determine if any mineralogical changes to the reservoir (e.g., mineral dissolution or precipitation). If time permits, potential geological storage sites be looked at across the UK, onshore and offshore. Specifically looking into Permian and Triassic Salt deposits and saline aquifers and DOGF on the UKCS.