Method and system for improving boiler effectiveness

A method for operating a steam generator system, the method comprising:

• providing a steam generator system comprising a steam generator vessel, an air supply system, air regulator means and an air preheater with heat transfer elements therein, with the air supply system being in communication with the steam generator vessel through the air preheater, and with the steam generator vessel being in communication with the air preheater;
• providing a control unit comprising a computer processor, memory and signal processing electronics;
• providing, by the air supply system and via the air regulator means, a first amount of air to the air preheater, the magnitude of the first amount of air being dependent on performance of the heat transfer elements;
• providing, by the air preheater, at least a portion of the first amount of air to the steam generator vessel as combustion air;
• discharging from the steam generator vessel a flue gas mixture;
• flowing at least a portion of the flue gas mixture into the air preheater;
• mitigating SO3 in the flue gas mixture before the flue gas mixture enters the air preheater;
• the heat transfer elements having a heat transfer capacity in excess of that required to preheat the combustion air, the air preheater having a cold end metal which is at a lowest temperature in the air preheater;
• transferring a first amount of heat away from at least one of the steam generator vessel, the air preheater, and the flue gas mixture sufficient to establish a first temperature of the flue gas mixture exiting the air preheater of a magnitude such that the cold end metal of the air preheater has a cold end metal temperature that is greater than or equal to a water dew point temperature in the air preheater and such that the cold end metal temperature is less than a sulfuric acid dew point temperature at the cold end metal, the sulfuric acid dew point temperature being a temperature at which sulfuric acid condenses on the heat transfer elements;
• providing an infrared sensor in proximity to the cold end metal;
• determining, with the infrared sensor, the cold end metal temperature;
• comparing the cold end metal temperature to the water dew point temperature;
• and
• controlling, with the control unit, the cold end metal temperature to be no less than the water dew point temperature.