🔍 Key Concepts

• steam-assisted fuel atomizer operation (how steam and fuel interact at the burner) • How fuel flow to the burner is normally increased or decreased with boiler load changes • Difference between supply pressure and return pressure in fuel systems

💭 Think About

• Which of these four options would most directly change how much fuel actually reaches the burner as steam demand increases or decreases? • Think about how a boiler control system responds when more steam is needed: what variable does the system change to increase firing rate? • Which factor mainly affects the rate of fuel delivery, and which factors mainly affect quality of atomization or spray shape?

✅ Before You Answer

• Identify which choices change fuel quantity to the burner versus which mainly change spray characteristics. • Ask yourself: in a typical boiler control loop, what signal is adjusted to match fuel flow to steam demand? • Be sure you can explain, in your own words, the difference between fuel supply pressure and fuel return pressure and what each one influences.