🔍 Key Concepts

• Boiler combustion efficiency and how clean burning surfaces affect it • Effects of carbon (soot) deposits on air/fuel mixing and heat transfer • Relationship between burner fouling and fuel consumption for same steam output

💭 Think About

• If burner throats and diffusers are covered with carbon, what happens to the path and mixing of air and fuel? Does that usually increase or decrease the quality of combustion? • When soot or carbon builds up on any heating surface, do you usually get more heat into the water/steam, or less, for the same amount of fuel? • Think about what the boiler operator would notice on fuel rate and stack temperature when burners get dirty—would the plant be using fuel more or less efficiently?

✅ Before You Answer

• Consider whether soot/carbon acts as an insulator or a conductor for heat transfer surfaces • Ask yourself if dirty burners tend to make the boiler more or less efficient overall • Verify which option directly reflects the normal result of poor combustion and fouling inside a boiler