TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Method: The method includes receiving a liquid component of feed stream and vaporizing the liquid component to form the vaporized feed stream component. A substantial portion of solids in the vaporized feed stream component are formed during vaporization of liquid component. The liquid component of feed stream is free of solids before being vaporized to form the vaporized component of feed stream. Removing solids from vaporized feed stream component includes passing the vaporized feed stream component through a filter assembly containing filter(s).    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The vaporized feed stream component contains greater amount of solids than the liquid feed stream component. The solids comprise colloidal silica and/or carbon-containing solids. The liquid and vaporized feed stream components comprise water and/or carbon-containing feedstock.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Components: The treatment region comprises filter(s) (48) including sintered filter element(s) and having outside and inside diameter. The filter receives a flow of vaporized component of the feed stream from the outside diameter to the inside diameter. The hydrogen-producing region comprises reforming catalyst(s) (62) and produces the mixed gas stream by steam reforming process. The hydrogen-producing region is a steam reforming region (66). Portions of vaporization region, treatment region, and hydrogen-producing region may be enclosed in a common housing. A portion of treatment region is configured to be accessible from external of the common housing without disassembling the common housing. The common housing includes portal(s) to provide access to portion of treatment region from external of the common housing. An insulated jacket encloses the common housing. Alternatively, the vaporization region and hydrogen-producing region are enclosed in a common housing, and the treatment region is connected with the vaporization region and hydrogen-producing region but positioned external of the common housing. The treatment region comprises filter(s) having an internal area. Portion(s) of the internal area is configured to be accessible from external of the filter without disassembling the filter. The filter includes portal(s) to provide access to portion of the internal area from external of the filter. The treatment region is removably coupled to the common housing by releasable fasteners designed to permit connection and reconnection of the treatment region relative to the common housing. An insulated jacket encloses the common housing and the treatment region, or an insulated jacket encloses the common housing and an insulated shroud encloses the treatment region. The fuel processing system comprises a separation region (32) to receive the mixed gas stream and to produce a hydrogen-rich stream containing pure hydrogen gas and a byproduct stream containing substantial portion of other gases.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The vaporized feed stream component contains greater amount of solids than the liquid feed stream component. The solids comprise colloidal silica and/or carbon-containing solids. The liquid and vaporized feed stream components comprise water and/or carbon-containing feedstock.