Degradation Mechanism in Mechanical Components of CCS Facilities: The Malaysian Environment

Abstract

Carbon Capture and Storage (CCS) implementation is one of the crucial mitigation strategies for Malaysia to achieve net-zero emissions by 2050. However, there are critical engineering challenges, particularly regarding the material degradation of CCS infrastructure in tropical environments. Mechanical components such as pipelines, steel structures, and pressure vessels in tropical marine and supercritical CO₂ (s-CO₂) environments are exposed to humid, saline, and impurity-rich environments that accelerate corrosion, stress corrosion cracking (SCC), and fatigue failures. Thus, to ensure successful Malaysia’s decarbonisation roadmap, it is important to ensure the reliability and durability of CCS infrastructure under tropical climatic conditions. International guidelines exist for material selection in CCS. However, they are largely based on temperate environments and overlook the harsher dynamics of tropical marine atmospheres. Hence, there are significant knowledge gaps that need to be addressed. This review investigates the material degradation mechanisms that affect CCS mechanical components in tropical environments, with a focus on corrosion behaviour, stress-related failures, and protective measures. Research and review articles focusing on mechanical corrosion in tropical environments and CO₂ application were searched, reviewed and synthesised. Key points from the articles were extracted and highlighted in a synthesis matrix, which consisted of the focus area, data collection method, components and environments studied, results and the key findings. There is limited existing studies on corrosion of equipment at CCS facility in Malaysia. Most of the available data are extracted from global cases. From this review, it can be concluded that carbon steels undergo accelerated corrosion and SCC under CO₂-saturated marine conditions, with corrosion rates increasing alongside temperature and applied stress. Chromium-enriched weathering steels have significantly better performance, developing compact, protective rust layers that are resistant to tropical marine exposure. In the long term, martensitic stainless steels exhibit initial rapid corrosion but stabilise over time, outperforming low-carbon steels. Impurity levels in s-CO₂ pipelines are critical. Hence, Oxygen and Sulfur Dioxide (SO₂) concentrations above 100 ppm will cause corrosion to worsen drastically. Besides, chloride deposition decreases inland but is strongly influenced by wind, while dynamic models using machine learning offer better prediction of corrosion severity compared to static classification. These findings highlight the urgency for Malaysia specific material guidelines, predictive corrosion models, and monitoring strategies tailored to tropical climates. Future work should integrate real-time environmental sensors with advanced modelling to improve maintenance planning and extend CCS infrastructure life cycles. Such measures are vital to ensure the safe and sustainable operation of Malaysia’s CCS facilities in achieving net-zero ambitions.