NOVELTY - A system comprises steam source (12), configured to produce steady flow of steam; mixing tube (16) extending between steam source and prereformer (18), mixing tube having opening configured to receive fuel into flow of steam passing through mixing tube; mixing tube is allow thorough mixing of fuel within flow of steam such that to form uniform mixture; prereformer operatively connected to mixing tube, such that to receive mixture within prereformer and to treat portion of mixture with at least one catalyst; and reformer operatively connected to prereformer.    USE - For reducing carbon deposition in a steam reforming assembly for hydrocarbon fuels and hydrogen to fuel cell.    ADVANTAGE - The system has excellent high temperature properties; the process increases the velocity of the gas within the system, which shortens the residence time of fuel in the header of the inlet reformer panel.    DETAILED DESCRIPTION - A system comprises steam source, configured to produce steady flow of steam; mixing tube extending between steam source and prereformer, mixing tube having opening configured to receive fuel into flow of steam passing through mixing tube; mixing tube is allow thorough mixing of fuel within flow of steam such that to form uniform mixture; prereformer operatively connected to mixing tube, such that to receive mixture within prereformer and to treat portion of mixture with at least one catalyst; and reformer operatively connected to prereformer. The system further comprises a superheater operatively connected between steam source and mixing tube where steam from steam source is transferred to superheater, and superheater, super heats the steam from steam source. The reformer has at least one catalyst located within an inlet portion of reformer. The reformer has inlet, which having a header and where at least a portion of header is lined with a preselected catalyst. The fuel is delivered to mixing tube through a cooled delivery line. The cooled delivery line is cooled by a water line proximate to delivery line. The fuel is introduced into flow of steam by atomizing preselected quantity of fuel through a hollow needle. The fuel is mixed in to steam in a molar concentration ratio of three or more moles of steam per mole of carbon contained in fuel. INDEPENDENT CLAIMS are included for following:    (1) reducing carbon deposition in reformate fuel cell applications, involving stream of steam having a preselected quantity of superheat within stream of steam; adding a preselected quantity of fuel into stream of steam; and mixing fuel and stream of steam such that to obtain uniform mixing of fuel within stream of steam; and    (2) reducing carbon deposits in steam reformer apparatuses involving, passing steam hydrocarbon mixtures through a reformer that has header containing at least one catalyst.    DESCRIPTION OF DRAWING(S) - The figure shows schematic view of system.    Steam source (12)    Superheater (14)    Mixing tube (16)    Prereformer (18)    Reformer. (22)