🔍 Key Concepts

• Combustion chemistry in marine boilers and diesel engines • Which flue gas components carry away the most latent heat of vaporization • Role of inert gases versus reactive gases in heat generation or loss

💭 Think About

• Think about which element, when it burns, produces a product that can change phase (from vapor to liquid) in the exhaust and take a lot of heat with it. • Ask yourself: which of these elements mainly just "goes along for the ride" as an inert gas, and which actually forms compounds that absorb or release large amounts of heat? • Consider the typical combustion equation for fuel oil (which contains C, H, S) and air (which contains mostly N and O). Which element’s combustion products are most associated with moisture in the stack gas?

✅ Before You Answer

• Identify which combustion product leads to water vapor in the exhaust and related latent heat loss. • Distinguish between heat generated by burning a fuel component and heat carried away by its combustion products. • Remember that nitrogen (N₂) in air is mostly inert in normal combustion and mainly absorbs heat without chemically burning.