Start-up method of bubble column slurry bed reactor

A start-up method of a bubble column slurry bed reactor for producing hydrocarbons by the Fischer-Tropsch synthesis reaction, the method comprising:

• a first step of filling a slurry, in which a Fischer-Tropsch synthesis reaction catalyst particles are suspended in a slurry preparation oil, which is a hydrocarbon oil in which the sulfur content and the aromatic content are respectively 1 mass ppm or lower, the 5% distillation point is 120 to 270° C., and the 95% distillation point is 330 to 650° C., into the reactor, wherein the filling is performed such that the volume of the heavy oil component comprising components with a boiling point of 300° C. or more in the hydrocarbon oil within the slurry filled into the reactor is 50% or more with respect to the volume of a void space in the reactor below the lowest end of the lowest part heat removal line installed in the reactor, and such that the height of the liquid surface of the slurry in the reactor is lower than the height at which airborne droplets of the liquid in the reactor begin to be carried by the gas flowing out from the outlet of the reactor upper part;
• and
• a second step of, in a state where synthesis gas that is primarily hydrogen and carbon monoxide is introduced into the slurry filled into the reactor, increasing the reaction temperature of the reactor, and starting the Fischer-Tropsch synthesis reaction;
• wherein
• the slurry preparation oil is the hydrocarbon oil within the slurry at the point where the carbon monoxide conversion rate of the Fischer-Tropsch synthesis reaction has reached 20 volume % in the second step in which the amount of the light oil component comprising components with a boiling point of less than 300° C. is equal to or more than the volume in terms of the slurry preparation oil such that the light oil component is present as liquid in the reactor at 1 volume % or more within the slurry in terms of the hydrocarbon oil.