Question 1403 Deck General

The correct answer is C) At least one meter must be decanted from the source tank. The reasoning behind this is that when using a crude oil washing system, the oil in the source tank must be free of any sediment or water that may have accumulated at the bottom of the tank. By decanting at least one meter from the source tank, this ensures that the washing machines are drawing from the cleaner, top layer of the oil, and not from any sediment or water that may be present at the bottom of the tank. This is a necessary precaution to prevent damage to the washing machines and ensure the effectiveness of the crude oil washing process. The other options are incorrect because they do not address the specific issue of removing sediment and water from the source tank. Lowering the oxygen content (A) and sampling for compatibility (B) are not directly relevant to this particular precaution, and there is no requirement for the source tank to have been crude oil washed in the past 150 days (D).