Life Cycle Assessment (LCA) Study of High Entropy Alloy Geo-Coat Technologies Deposited Through High Velocity Oxy-Fuel Thermal Spraying, Laser Cladding and Electro-Spark Deposition Processes

Abstract

The aggressive nature of the medium to high-temperature geothermal resources makes the geothermal plant components vulnerable to corrosion, erosion and scaling. Hence, keeping the integrity of the various plant components is a big challenge nowadays. To combat the corrosive geothermal environment, the Geo-Coat project proposes the components to be made of carbon steel and coated with cost-effective corrosion-resistant, erosion-resistant and antiscaling materials. Five high entropy alloys (HEAs) coating materials deposited through High-Velocity Oxy-Fuel spray (HVOF), Laser Cladding (LC) and Electro-Spark Deposition (ESD) have been studied. Determining the environmental impacts of these coating materials and their deposition processes is an essential step in designing a green and sustainable technology. Therefore, in this study, the environmental impacts of these HEA coatings have been evaluated by a cradle to gate approach, by using SimaPro 9.0.0.49 LCA tool, and life cycle impact assessment (LCIA) methodology IMPACT 2002+, version 2.14. For life cycle inventory (LCI) data of the study, ecoinvent 3.4 database has been used. The environmental impacts of these material syntheses have been evaluated through quantification of the midpoint impacts and endpoint damage categories. This paper briefly presents the results of the LCIA and suggests the best combination of coating material and its deposition technique, which can be used for identifying and promoting green and sustainable coatings for geothermal plant components. Funding for this work is acknowledged from the European Commission under the project: Geo-Coat: Development of Novel and Cost-Effective Corrosion Resistant Coatings for High Temperature Geothermal Applications (Grant ID: LCE-GA-2018-764086).