LABORATORY AND ON-SITE FINDINGS DEMONSTRATING THE GREATER EFFECTIVENESS OF BIPHASE WATER-BASED COMPRESSOR CLEANERS OVER MONOPHASE CLEANERS

摘要

Compressor washing is a widely applied method to reduce the fouling rate of compressor blades by on-line washing and restore lost power by off-line washing. One of the factors influencing the effectiveness of a wash procedure is the efficiency of the detergent used for washing. This especially in the presence of hydrophobic contamination such as oily and carbon type deposits that can be difficult to penetrate and loosen by water-based detergents. In this paper, a comparison of cleaning performance is made between monophase water-based compressor cleaners and a biphase water-based compressor cleaner. Most of the currently used water-based compressor cleaners are monophase solutions. Their main active ingredients are surfactants which lower surface tension and interfacial tension allowing detachment and emulsification of foulant from a compressor blade. Biphase compressor cleaners are also formulated with surfactants, however due to their sub-micron heterogeneous nature they not only provide detachment and emulsification but a much more effective capability to solubilize even hydrocarbon type contamination. Cleaning efficiencies of these cleaners were evaluated in the laboratory using various test methods including US MIL-PRF-85704C. All of these performed tests confirm the significantly higher effectiveness of the biphase compressor cleaner. To validate the results from the laboratory tests a direct comparison of a monophase cleaner and a biphase cleaner was performed at a power station in the UK. After about four years of frequent washing with the monophase cleaner on two engines, one GT was then washed three times consecutively offline within a time period of six months with the biphase cleaner. In the second GT, washing was continued with the monophase cleaner. The visual inspection during a major overhaul very clearly showed a significantly higher removal of contamination from the GT washed with the biphase compressor cleaner.