🔍 Key Concepts

• Steam drum internals: know the difference between devices that handle mud/settled solids at the bottom versus scum/floating impurities at the surface. • Surface blow (scum) vs bottom blow: floating oil/foam is removed from near the normal water level, not from the lowest part of the drum. • Location in the illustration: the removal point for floating impurities will be close to the water surface line and lead to an overboard or blowdown connection.

💭 Think About

• Look at where the normal water level is drawn. Which labeled item is positioned right at or just below this level and has a path to be discharged from the drum? • Which labeled item is shaped or located like a trough or perforated pipe along the water surface, rather than a single vertical pipe or a bottom header? • Compare the items that clearly serve other duties (such as steam outlet or feed inlet). Which remaining item is specifically arranged to skim material from the surface layer of the water?

✅ Before You Answer

• Verify which labeled item is nearest the water surface and extends horizontally where scum would collect. • Confirm that the item you choose has a connection leading to a blowdown/discharge line, not to steam takeoff or feedwater inlet. • Make sure the device you select is not located on the very bottom of the drum, since that would handle sludge/mud, not floating impurities.