Question 105General Subjects - QMED

70% to pass

What statement is true concerning the polishing coalescer filter of an oily-water separator?

AThe coalescing filter is typically a hydrophilic filter meaning that small droplets of entrained water of the oily-water mixture coalesce on the filter and form large globules of water that sink to the bottom of the filter housing.

BThe coalescing filter is typically an oleophilic filter meaning that small droplets of entrained oil of the oily-water mixture coalesce on the filter and form large globules of oil that sink to the bottom of the filter housing.

CThe coalescing filter is typically a hydrophilic filter meaning that small droplets of entrained water of the oily-water mixture coalesce on the filter and form large globules of water that rise to the top of the filter housing.

DThe coalescing filter is typically an oleophilic filter meaning that small droplets of entrained oil of the oily-water mixture coalesce on the filter and form large globules of oil that rise to the top of the filter housing.

AI Explanation

The correct answer is D. The coalescing filter of an oily-water separator is typically an oleophilic (oil-attracting) filter, meaning that small droplets of entrained oil in the oily-water mixture coalesce on the filter and form larger globules of oil that rise to the top of the filter housing. This allows the oil to be separated from the water and discharged overboard in compliance with environmental regulations. The other options are incorrect because a hydrophilic (water-attracting) filter would cause the water droplets to coalesce and sink, which is the opposite of what happens in an oily-water separator. Additionally, the oil globules rise to the top, not the bottom, of the filter housing.

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