Corrosion and Scaling in Geothermal Heat Exchangers

Abstract

Geothermal power is an attractive and environmentally friendly energy source known for its reliability and efficiency. Unlike some renewables like solar and wind, geothermal energy is available consistently, making it valuable for mitigating climate change. Heat exchangers play a crucial role in geothermal power plants, particularly in binary cycle plants, where they represent a significant portion of capital costs. Protecting these components from deterioration is essential for improving plant profitability. Corrosion is a common issue due to direct contact with geothermal fluid, which can lead to heat exchanger failure. Additionally, temperature changes within the heat exchanger can cause scaling, reduce heat transfer efficiency, or even block the tubes. This review critically examines the challenges posed by corrosion and scaling in geothermal heat exchangers, with a primary focus on three key mitigation strategies: the application of corrosion-resistant alloys, the utilization of protective coating systems, and the introduction of anti-scaling agents and corrosion inhibitors into the geothermal fluid. The paper discusses recent strides in these approaches, identifying promising advancements and highlighting impending obstacles. By bridging existing knowledge gaps, this review aims to offer valuable insights into material selection, heat exchanger design, and the progression of geothermal energy production. Ultimately, it contributes to the ongoing endeavor to harness geothermal energy as a sustainable and enduring solution to our energy needs.