Question 270Motor Plants - Assistant Engineer

The correct answer is A) throughput. For optimum results in centrifugal purification of heavy fuel oil, the fuel should be processed at the lowest practicable throughput. This allows for more effective separation of contaminants and water from the fuel, as a lower throughput provides more residence time in the centrifuge and enhances the purification process. The other answer choices are incorrect because they do not directly relate to the optimal conditions for centrifugal purification. The additive percent, cetane number, and total base number (TBN) are not the primary factors that influence the effectiveness of the centrifugal purification process.