🔍 Key Concepts

• Trace the piping connected to item 15 to see where it takes suction and where it discharges. • Understand the roles of area 23 (evaporator/brine section) and area 24 (condenser/distillate section) in a flash-type distilling unit. • Consider how the chemical cleaning system would be arranged in the diagram (look at item 12 and nearby lines).

💭 Think About

• Follow the line from item 15 backward: from which section or space does it draw fluid—23, 24, or another low point? • Follow the line from item 15 forward: does it send the fluid to overboard, a drain, back to the evaporator, or into a cleaning loop? • Compare the function implied by that flow path with each choice: which option matches what that pump would realistically be doing in normal or secured operation?

✅ Before You Answer

• Verify whether item 15 is symbolized as a pump (look at the symbol shape and nearby motor or drive). • Check if the suction side of item 15 is connected to the bottom/low point of area 23 or 24, or to a separate drain/chemical tank line. • Confirm whether valve 12 is in the same loop as item 15, and whether that loop appears to be a temporary cleaning circuit or a drain/emptying line.