NOVELTY - A fuel reforming system has pressure-medium supplier, modification reactor, heater for the reactor, water-recovering unit, and fuel cell. The supplier supplies fuel and water to the reactor which generates reformed gas using the fuel and water. The heater heats the reactor using combustion heat of wastewater ejected from fuel cell. The water-recovering unit recovers and supplies water to the upstream side of the reactor.    USE - For manufacturing hydrogen rich gas (claimed) for fuel cells.    ADVANTAGE - The fuel reforming system rapidly modifies hydrocarbon group fuels, such as gasoline and light oil, under low-temperature conditions. The compact, reliable and economical system reduces byproducts, such as carbon monoxide and methane, and prevents nitrogen dilution. High responsiveness and start-up capability are ensured. Water is recovered efficiently in a liquid state. The energy recovered by the pressure-preservation valve is suitably used for power source of pumps and compressors. The fuel and water are reacted in a favorable mixed state. Since the mixed fluid permeates even in the narrow pore of modification catalyst, the utilization factor of active point is improved and modification reaction is advanced efficiently. The need for measures against heat resistance of reactor is eliminated.    DETAILED DESCRIPTION - A fuel reforming system has a pressure-medium supplier, a modification reactor, a heater for the modification reactor, a water-recovering unit, and a fuel cell. The supplier supplies a hydrocarbon group fuel and water to the modification reactor in a high-pressure state. The modification reactor generates reformed gas from the fuel and water, using a modification catalyst provided internally. The heater heats the modification reactor using the combustion heat of wastewater ejected from the fuel cell. The water-recovering unit cools the reformed gas, recovers water in the reformed gas in high-pressure state, and supplies the recovered water to the upstream side of the modification reactor. The system supplies the manufactured hydrogen rich gas to a fuel cell. An INDEPENDENT CLAIM is included for manufacture of hydrogen rich gas, which involves controlling pressure, temperature, liquid space velocity, and/or fuel/water ratio using the modification reactor, contacting the fuel and subcritical/supercritical water with the modification catalyst to generate reformed gas, and cooling the reformed gas and removing water in the reformed gas.    DESCRIPTION OF DRAWING(S) - The figure shows the schematic drawing of the fuel reforming system. (Drawing includes non-English language text).