Long Term Measurements of High Temperature Corrosion in a Waste Incineration Plant Using an Online Monitoring System

High-temperature corrosion is a frequently observed phenomenon in waste incineration facilities. Municipal solid waste presents substantial corrosion potential attributed to elevated chlorine content and significant inhomogeneity in calorific value and chemical composition, rendering stable plant operation and corrosion control challenging. Conventional countermeasures, such as cladding or reduced steam parameters, lack temporal resolution and incur substantial costs or reduced efficiency. For this study, a waste incineration plant was equipped with an online corrosion monitoring system featuring ten sensors distributed across three vertical boiler passes. The system employs an electrochemical measurement principle to enable the detection of corrosion with temporal resolution. The recorded data reveals decreasing corrosion attack and increasingly stable deposits along the flue gas path. Combined with the temperature measurements, the sensor data proves the effectiveness of the shower cleaning in the third pass and confirms successful removal of the deposits. Statistical analysis shows a correlation between CO content and sensor data, while other parameters (e.g., steam flow, flue gas temperatures) exhibit no conclusive correlations, emphasizing the system’s added value. Chemical analysis of the electrodes and deposits reveal significant indications of chlorine and sulfur, suggesting chlorine-catalyzed active oxidation as the predominant corrosion mechanism.