Coast Guard Exams
Question 246General Subjects - Assistant Engineer70% to pass

When the oily-water separator, shown in the illustration, is in operation and processing clear bilge water, what should be the internal water level? Illustration GS-0153

Diagram for question 246
AI Explanation
The correct answer is C) The water level should be located in the upper section of the tank. When the oily-water separator is in operation and processing clear bilge water, the internal water level should be maintained in the upper section of the tank. This allows the water to flow through the coalescer bed (item 9) and the oil/water interface to remain in the upper portion, facilitating the separation of oil from the water. The water level is not controlled by the flow control valve (item 14), which is used to regulate the flow rate, not the water level. There is no need to maintain the water level slightly above the coalescer bed, and the tank should not be operated without any water level.