TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The case of the burner, the reformer and the steam generator is mutually flange and laminated in mutually sealing manner. The burner is performed the burner role by injecting priming fuel during start up, includes an integrating burner to supply air and passing unburned gas via the stack after role of a combustor, and blocking injection of the priming fuel if the reformer temperature rising more than a predetermined temperature. The burner is provided in form of metal fiber surface burner, and it surface is uniformly heated. The metal fiber surface burner includes a tube useful for multiple air supply nozzles and a tube useful for a gas supplying nozzle, and repeatedly arranged in sequence manner at regular intervals to heat the surface uniformly, a porous plate position spaced a predetermined distance from the top of the tube for multiple air supply nozzles and a tube for a gas supplying nozzle, for mixing of the gas and air to prevent deflection of the metal fiber during combustion. The tube for multiple air supply nozzles and tube for gas supplying nozzle is connected to a priming fuel inlet and an air inlet by manifolding side of an inlet to constant distribute of the supplied air or gas. The reformer includes multiple vertical through-holes for serving as path in the steam generator, does not introduced flame and combustion gas into the reformer, and performing heat transfer from the flame and combustion gas into the reformer, a fuel inlet for flowing the fuel gas, provided to one aspect, a steam inlet for flowing the discharged steam from the steam generator, provided to other aspect, a reforming gas outlet for discharging the reformed gas, provided on the other aspect, a catalyst inlet for filling catalyst inside the reformer. The one aspect and the other aspect face are made of the corn-type shape which are protruded outside and are formed uniform inflow and exhaustion. The bottom plate of the burner is made of inconel plate, and the through-hole is made of inconel tube. The catalyst inlet is sealed by using melex connector blocking apparatus to prevent the catalyst after filling. The steam generators further comprises an exhaust gas outlet for discharging the combustion gas delivered from the burner, and the exhaust gas is utilized to preheat the process air which is supplied to the stack including a heat exchanger supplier, at least two water inlet, a coil type evaporation tube passing through interior of the steam generator to each of the water inlet, provided corresponding to number of the water inlet, and a steam discharge port to release the salted steam from inside the steam generator, and extending outside of the steam generator, combined outlet side of the evaporation tube. The heat exchanger includes a bending fluid path which is pin types form the inside and vertical plate type from the outside, located on both sides of the stack, provided in pairs, an exhaust gas inlet port located at top opposite side of the stack, a gas discharge port for heat exchanging in lower portion of the aspects, contacted with the stack. Preferred Method: The method further comprises (i) discharging a reformed gas via the steam reforming reaction with fuel gas from inside the packed catalyst reformer, heat transferring inside the reformer from the flame and combustion gases, and supplying steam with fuel gas into the reformer, and (ii) evaporating water into steam by absorbing heat from combustion gases and flame, passing via the through-hole and supplying water to the steam generator. The preheating step is carried out by improving heat exchange efficiency by forming bending fluid path between the process air and the exhaust gas, inflowing the flue gas into the heat exchanger via the inlet port, and the flue gas preheating the processing air by performing a heat exchanging the processing air via the bending fluid path, and the processing air is introduced internal of the stack via a gas outlet provided with heat exchanger in lower portion of the aspects and contacted with the stack.