Both crude oil washing and water washing use direct impingement to remove residue from tanks. Crude oil washing has an additional advantage, in utilizing __________.

Correct Answer: Option B — the solvent effect of the crude oil

Crude oil washing (COW) utilizes the inherent solvent properties of the crude oil itself to dissolve waxy deposits and sludge on tank surfaces. This chemical action, combined with the mechanical impingement of the jets, is significantly more effective at cleaning than water washing alone.