Abstract: A tubular probe has spaced apart bands or patches of the same material as the probe body attached to the probe body by an electrically insulating, high temperature material. A series of cooling tubes are provided within the probe body to direct cold air to the regions near each band. One or more probes is placed in a furnace or boiler above the ammonia injection zone. When ammonium bisulfate forms on the probe it completes an electrical circuit between the probe body and the bands and will also cause corrosion of the probe. The presence of ammonium bisulfate is detected by a change in resistance between the bands and the probe body. Electrochemical noise is generated during the corrosion process. A corrosion rate can be determined from the level or amount of electrochemical noise that is detected.

Abstract: A tubular probe has spaced apart bands or patches of the same material as the probe body attached to the probe body by an electrically insulating, high temperature material. A series of cooling tubes are provided within the probe body to direct cold air to the regions near each band. One or more probes is placed in a furnace or boiler above the ammonia injection zone. When ammonium bisulfate forms on the probe it completes an electrical circuit between the probe body and the bands and will also cause corrosion of the probe. The presence of ammonium bisulfate is detected by a change in resistance between the bands and the probe body. Electrochemical noise is generated during the corrosion process. A corrosion rate can be determined from the level or amount of electrochemical noise that is detected.

Abstract: A method for monitoring and reducing corrosion in superheater and reheater furnace tubes measures electrochemical activity associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. A sensor containing two electrodes spaced apart by an insulator is used. The surface of a boiler tube is one of the electrodes. The sensor is connected to a corrosion monitor. The monitor contains a computer and software, which determines a corrosion rate from the measured electrochemical activity. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the furnace operator of the furnace or an Adaptive Process Controller (APC) adjusts one or more burners to change the combustion products that are responsible for the corrosion.

Abstract: A method for monitoring and reducing corrosion in furnace boiler tubes measures electrochemical noise associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. This noise is detected using a probe at the boiler waterwall surface that is connected to a corrosion monitor. The monitor contains a computer and software which determines a corrosion rate from the measured electrochemical noise. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the operator of the furnace or an Adaptive Process Controller (APC) is notified and adjusts one or more burners to change the combustion products that are responsible for the corrosion. Such an adjustment could be made by changing the amount of air or fuel being provided to the burner or other air slots or air ports.

Abstract: A method for monitoring and reducing corrosion in furnace boiler tubes measures electrochemical noise associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. This noise is detected using a probe at the boiler waterwall surface that is connected to a corrosion monitor. The monitor contains a computer and software which determines a corrosion rate from the measured electrochemical noise. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the operator of the furnace or an Adaptive Process Controller (APC) is notified and adjusts one or more burners to change the combustion products that are responsible for the corrosion. Such an adjustment could be made by changing the amount of air or fuel being provided to the burner or other air slots or air ports.