Research on metallurgical and chemical inhibition techniques to reduce corrosion in high-acid geothermal wells

地热能是一种公认的可再生能源，可在全球范围内提供可靠的基本负荷发电。提取地热水作为一种能源至关重要，而且其使用量正在增加。开发可再生地热能源的一个问题是生产酸性卤水，这会导致过度腐蚀，并经常出现油井套管、套管头穿孔和井面管道故障等结垢问题，这些问题往往无法处理。这项研究将加深我们对碳钢和不锈钢在强酸性(pH~2.5-3)条件下受二氧化碳影响的人造地热卤水中的腐蚀行为和腐蚀机理的基本认识。这些知识将用于评估地热资产中的相关腐蚀和结垢威胁及其缓解。根据这一初始数据集，将对一系列经过战略选择的表面活性剂在强酸性溶液中控制腐蚀的能力进行评估。这些观察结果将首先加强对这类系统中腐蚀抑制的了解，其次，有助于指导该行业开发新的方法、化学物质和地热环境中腐蚀控制的指南/建议。这项工作的目标是：-设计和调试一种定制的实验高压灭菌器系统，用于在高温和高压环境中对腐蚀基材进行质量损失和电化学分析。-对各种高温条件和流体成分进行腐蚀实验，以提高对高酸度地热系统中的腐蚀机理的了解。-使用相关的测试、分析和表面表征技术和方法(质量损失、电化学方法、扫描电子显微镜-EDX、光学轮廓术、FTIR光谱)来确定腐蚀机理-分析候选化学品在高酸度系统中的性能，开发新的测试战略，将实验室扩展到地热领域。-专注于开发和改进更环保的腐蚀缓蚀剂的测试方法，分析它们的化学和物理性质，并将其与缓蚀性能联系起来，以支持具有改进功能的新化学物质的开发。-强调开发的环境友好型表面活性剂在存在大量矿物结垢(地热系统的典型)的情况下的表现。该提案与能源和工程研究主题(特别是‘电化学科学’和‘能源应用材料’的子主题)保持一致。这一建议也符合EPSRCS繁荣成果框架，特别是：(I)有韧性的国家，(Ii)有生产力的国家(下一代解决方案)和(Iii)有生产力的国家(负担得起的解决方案和可持续社会)。

Geothermal energy is a widely recognised renewable energy resource that provides reliable base load generation worldwide. The extraction of geothermal water for use as an energy source is of paramount importance and its usage is increasing. A problem in exploiting renewable geothermal energy sources is the production of acidic brine, that leads to excessive corrosion and often scaling issues of well casing, casing head perforation and well surface piping failures, that are often unmanageable. This study will improve our fundamental understanding regarding the corrosion behaviour and the corrosion mechanism of carbon steel and stainless steels exposed to an artificial geothermal brine influenced by carbon dioxide under strongly acidic (pH ~2.5-3) conditions. This knowledge will be used to assess relevant corrosion and scaling threats and their mitigation in geothermal assets. From this initial data set, a series of strategically selected surfactants will be evaluated in their ability to control corrosion in strongly acidic solutions. These observations will firstly enhance the understanding of corrosion inhibition in such systems and secondly, help guide the industry through the development of new methods, chemistries and guidelines/recommendations for corrosion control in geothermal environments. The objectives of the work are to:- Design and commission of a bespoke experimental autoclave system for mass loss and electrochemical analysis of corroding substrates in high temperature and high-pressure environments. - Perform corrosion experiments for various high temperature conditions and fluid compositions to improve the understanding of corrosion mechanisms in high acidity geothermal systems. - Use associated testing, analytical and surface characterization techniques and methods (mass loss, electrochemical methods, SEM-EDX, optical profilometry, FTIR spectroscopy) to determine the corrosion mechanisms- Analyse the performance of candidate chemicals in high acidity systems, developing novel testing strategies for scaling of laboratory to geothermal fields.- Focus on the development and improved testing methods for more environmentally friendly corrosion inhibitors, analysing their chemical and physical properties and linking this to inhibition performance to support the development of new chemistries with improved functionality.- Highlight how the developed environmentally friendly surfactants perform in the presence of significant levels of mineral scaling (typical of geothermal systems)The proposal aligns within the Energy and Engineering research themes (particularly within the sub themes of ''Electrochemical Sciences'' and "Materials for Energy Applications"). This proposal also aligns with EPSRCs prosperity outcomes framework, specifically: (i) Resilient nation, (ii) Productive nation (next generation solutions) and (iii) Productive nation (affordable solutions and sustainable society).