Question 112Safety & Environmental - Assistant Engineer

The correct answer is C) the solvent effect of the crude oil. Both crude oil washing and water washing use direct impingement to remove residue from tanks. The key difference is that crude oil washing has an additional advantage of utilizing the solvent effect of the crude oil itself. The crude oil acts as a solvent, helping to dissolve and remove the residual oil and sludge deposits from the tank walls and bottom. This solvent effect is not present in water washing, which relies solely on the mechanical action of the high-pressure water jets. The other options are incorrect because they do not represent the unique advantage of crude oil washing over water washing. While higher temperature and pressure may play a role, the solvent effect of the crude oil is the primary additional benefit of this method.