Effect of Compressor Washing on the Performance of Industrial Gas Turbine

Abstract

Over the years, Industrial Gas Turbines (IGT) have found widespread applications in various sectors such as oil and gas, transportation, and power generation. Researchers have made significant contributions towards enhancing the performance and extending the lifespan of Gas Turbines (GT) through advancements like regeneration, pre-heaters, intercoolers, and more. The utilization of compressor washing techniques has also been explored, influenced by environmental factors. This has yielded varied results. In today's highly competitive market, coupled with the continuous rise in fuel costs, it has become crucial to develop effective measurement and control techniques for detecting, preventing, and controlling GT fouling. The continuous deterioration of GTs due to fouling has a direct impact on its performance and associated costs. This work focuses on investigating the significance of compressor washing on GT performance, specifically considering the fouling of compressor blades caused by Domestic Object Damage (DOD) and Foreign Object Damage (FOD), along with techniques to mitigate these issues. The evaluation encompasses online, offline, and combined (online and offline) compressor washing methods to determine the most effective approach in addressing fouling challenges faced by operators. The study was implemented using GT performance modelling tools - Pythia/Turbomatch - which involves simulation of the thermodynamic models of the engine. Results from the study indicate that at a compressor fouling level of 2% and a temperature of 200°C, a degradation of approximately 9% in power output, a 5% reduction in air mass flow and pressure ratio, and a decline of around 1.4% in gas generator turbine efficiency were observed. Further simulations involving an 8% fouling in compressor efficiency revealed that online compressor washing led to a recovery of 2.8%, offline washing achieved a recovery of 3.3%, while the combined method experienced a 6% performance recovery.