To provide a steam reforming method improving combustion efficiency of steam reforming furnace, decreasing the size of the steam reforming unit as a whole, simplifying the construction of the unit as a whole, and obtaining enough heat capacity of the produced steam.
This steam reforming furnace 1 is equipped with a switching regenerator type burner 40 and feed heating unit 2. Feed hydrocarbon and feed water (material of steam production) are emerged at the mixing part L3 of a feed supply pipe L1 and a water supply pipe L2, and the mixed liquid is introduced to a radiative heat conductor 21 and a convective heat conductor 23 of a feed heater 20. The radiative heat conductor is located in a high temp. region of the furnace of radiative part R, and accepts the radiative heat of the burner, and the convective heat conductor exchanges the heat with the combustion exhaust gas stream in the furnace of convection part C. The feed water is heated by the feed heater and vaporized as steam, and the feed hydrocarbon is heated by the feed heater. The mixed gas of the steam and the feed hydrocarbon produced at the feed heater is heat controlled at the convective heater, then the mixed gas is introduced to a catalyst tube 30 via mixed gas feed ducts L5 and L6. In the catalyst tube, reformed gas is produced by steam reforming reaction.
MITSUBISHI KAKOKI KAISHA LTD