Ioana Csaki
Politehnica University Bucharest, Romania
Title: In situ geothermal test results for multilayer coated steel
Biography
Biography: Ioana Csaki
Abstract
Geothermal steam contains dissolved minerals that can precipitate from the liquid and deposit onto the surface of the blades and rotors used for turbine producing geothermal energy. This process is called scaling and it occurs due to a change in temperature, pressures or PH values of the geothermal fluid disturbing the equilibrium of the system. When scaling occurs in geothermal equipment can create major problems in geothermal power production. A solution to avoid these problems consists in coating the steel made turbine blade with different materials layer. These coatings will provide corrosion and erosion resistance and durability for the equipment used in geothermal energy. Samples coated with Ni base alloy and Y using high velocity oxygen fuel technique was investigated after in situ testing in Hellisheiði power plant in Iceland. This paper aims to investigate the microstructure, physical and chemical properties of the coating providing a view on the composite materials behavior under geothermal steam. The studied composite powders are designed to prevent corrosion damages and have good reliability during the geothermal turbines life. Powder multi-component and composite layers obtained were investigated using a system characterization by X-ray difractometer and SEM and EDX analysis to obtain detailed information about the complex modifications inside of the structure and on interface deposition.