Method for hydrofining naphtha fraction and process for producing hydrocarbon oil

摘要

Disclosed is a method for hydrofining a naphtha fraction, the method comprising: a step in which the difference between the outlet temperature of a naphtha fraction hydrofiner and the inlet temperature thereof is estimated on the basis of the reaction temperature used in a Fischer-Tropsch synthesis reaction step and of the ratio of the rate at which a refined naphtha fraction is returned to the naphtha fraction hydrofining step to the rate at which the fraction is discharged from the naphtha fraction hydrofining step; a step in which the difference between the outlet temperature of the naphtha fraction hydrofiner and the inlet temperature thereof is measured; and a step in which the reaction temperature in the naphtha fraction hydrofining step is adjusted so that the measured difference between the outlet temperature of the naphtha fraction hydrofiner and the inlet temperature thereof becomes approximately equal to the estimated difference between the outlet temperature of the naphtha fraction hydrofiner and the inlet temperature thereof.