What can changes in combustion efficiency of a boiler be evaluated by?

What can changes in combustion efficiency of a boiler be evaluated by?

• A. Pressure and temperature
• B. Stack temperature and carbon monoxide levels
• C. Stack temperature and percentage of carbon dioxide
• D. Water level and flue gas composition

Answer: (C)

Changes in combustion efficiency of a boiler can be effectively evaluated by examining stack temperature and the percentage of carbon dioxide. When combustion efficiency improves, the amount of fuel that is converted into usable energy increases, which leads to a more complete combustion process. This is reflected in the flue gas composition, where higher levels of carbon dioxide indicate more efficient combustion because it means that less fuel is wasted and more of it has been converted into CO2 and water vapor. Stack temperature is also a crucial indicator; as efficiency increases, ideally, the stack temperature should decrease because less heat is being lost up the chimney. Conversely, if the combustion is inefficient, there may be higher levels of unburned fuel and other combustion by-products, which would typically manifest in lower levels of CO2 in the flue gases. Together, the analysis of stack temperature and carbon dioxide percentage provides a clear picture of how effectively the boiler is operating, making it the most suitable means to evaluate combustion efficiency.

Changes in combustion efficiency of a boiler can be effectively evaluated by examining stack temperature and the percentage of carbon dioxide.

When combustion efficiency improves, the amount of fuel that is converted into usable energy increases, which leads to a more complete combustion process. This is reflected in the flue gas composition, where higher levels of carbon dioxide indicate more efficient combustion because it means that less fuel is wasted and more of it has been converted into CO2 and water vapor.

Stack temperature is also a crucial indicator; as efficiency increases, ideally, the stack temperature should decrease because less heat is being lost up the chimney. Conversely, if the combustion is inefficient, there may be higher levels of unburned fuel and other combustion by-products, which would typically manifest in lower levels of CO2 in the flue gases.

Together, the analysis of stack temperature and carbon dioxide percentage provides a clear picture of how effectively the boiler is operating, making it the most suitable means to evaluate combustion efficiency.