🔍 Key Concepts

• Identify what system the component labeled 23 belongs to in this diagram (jacket water vs. feedwater/steam system). • Recall how a shell-and-tube heat exchanger typically works: which fluid usually goes inside the tubes and which stays on the shell side. • Determine which fluid is acting as the heating medium and which is the heated medium in this waste‑heat boiler system.

💭 Think About

• Follow the piping to and from device 23: Do its inlets and outlets come from the engine jacket water circuit or from the feedwater pump/boiler drum? • Ask yourself: in this diagram, is the jacket water giving up heat or receiving heat? What does that imply about what happens to the feedwater as it approaches the steam drum (24)? • Compare answers C and D to what you know about typical marine boiler heat transfer processes. Do those terms realistically describe what happens in a diesel jacket-water heat exchanger?

✅ Before You Answer

• Verify which lines into 23 are labeled the same as the jacket water connections elsewhere in the drawing. • Confirm that the feedwater line from the pump passes through 23 before entering the steam drum (24). • Eliminate any options that mention heat-transfer phenomena (azeotropic, subliminal) that are not normally associated with a simple jacket‑water/feedwater heat exchanger.