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Improving Boilers and Heater Energy Efficiency

Quiz Questions

1. Ideally, combustion breaks down the molecular structure of the fuel; the carbon oxidizes to carbon dioxide (CO2) and the hydrogen to ________ .
2. Controlling excess air is the most important tool for managing the energy efficiency and atmospheric emissions of a boiler system.
3. Which of the following is not a type of air and fuel control?
Mechanical jackshaft controls
Cross-limiting controls
Bucket control
On-Off and high-low controls
4. Emissions of sulphur dioxide (SO2) and nitrogen oxides (NOx) contribute to acid rain.
5. Except for natural gas, practically every fuel leaves a certain amount of deposit on the fireside of the tubes. This is called __________ , and it reduces heat transfer dramatically.
6. The heat exhausted from one part of the process can be used to heat another. This process is called _____________ ?
Heat cascading
Heat controlling
Heat management
None of the above
7. A CHP unit typically consists of a prime mover, such as a gas turbine or piston engine, and a heat recovery steam generator, which is a type of boiler. What is CHP?
Combined Hot air production
Combined heat production
Combined heat and power generation
Controlled Heat production
8. Heat exchangers can be used for preheating boiler feed water called economizers. Economizers typically increase the overall boiler efficiency by ________ percent.
4 to 5
3 to 4
3 to 6
2 to 6
9. Ongoing water evaporation in steam boilers and fresh boiler makeup water increases the concentration of these minerals and leads to scale formation. To prevent this, boiler water must be _________ periodically.
Shut down
Hone down
Blown down
Run down

Large boilers and those burning fuels with a high fouling tendency have soot blower systems that clean the fireside surfaces while the boiler is operating.