Question 74General Subjects - 1st Asst/Chief

70% to pass

If valve "D" is opened during the normal operation of the distiller shown in the illustration, which of the events listed will occur? Illustration MO-0111

Diagram for USCG General Subjects Chief: If valve "D" is opened during the normal operation of the distiller shown in...

AThe jacket water cooler will be overloaded, eventually causing a critical engine alarm.

BThe amount of vapor formed in the evaporator will increase.

CThe amount of vapor being formed in the evaporator will decrease.

DThe output of pump "7" will increase with a corresponding increase in pressure.

AI Explanation

The correct answer is C) The amount of vapor being formed in the evaporator will decrease. When valve "D" is opened during normal distiller operation, it allows more feed water to enter the evaporator. This additional feed water will dilute the concentrated brine solution, reducing the temperature difference between the brine and the vapor space. As a result, the amount of vapor being generated in the evaporator will decrease. The other options are incorrect because: A) opening valve "D" would not overload the jacket water cooler, B) the amount of vapor would decrease, not increase, and D) the output of pump "7" would not increase as a result of opening valve "D".

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