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

地热能是一种广泛认可的可再生能源，在世界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是至关重要的，它的使用正在增加。开发可再生地热能源的一个问题是酸性盐水的产生，这会导致套管的过度腐蚀和结垢问题，套管头穿孔和井面管道失效，这些问题通常都是难以控制的。本研究将提高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工地热盐水中的腐蚀行为和腐蚀机制的基本认识。这些知识将用于评估地热资产的相关腐蚀和结垢威胁及其缓解措施。根据这些初始数据集，将评估一系列战略性选择的表面活性剂在强酸性溶液中控制腐蚀的能力。这些观察结果将首先增强对此类系统中腐蚀抑制作用的理解，其次，通过开发地热环境中腐蚀控制的新方法、化学物质和指南/建议，帮助指导行业。该工作的目标是：-设计和调试一个定制的实验高压釜系统，用于高温高压环境下腐蚀基板的质量损失和电化学分析。-进行各种高温条件和流体成分的腐蚀实验，以提高对高酸性地热系统腐蚀机制的理解。-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，SEM-EDX，光学轮廓法，FTIR光谱）来确定腐蚀机制-分析候选化学品在高酸度系统中的性能，开发新的测试策略，以扩大实验室到地热田的规模。-专注于开发和改进更环保的缓蚀剂的测试方法，分析其化学和物理特性，并将其与缓蚀性能联系起来，以支持开发具有改进功能的新化学品。-强调开发的环境友好型表面活性剂在存在大量矿物结垢（典型的地热系统）的情况下的表现。该提案与能源和工程研究主题（特别是在“电化学科学”和“能源应用材料”的子主题内）保持一致。该提案还与epsrc的繁荣成果框架保持一致，具体而言：(i)有弹性的国家，（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的社会）。

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).