Patent Application
20070084119
The present invention relates to a reformer apparatus for catalytically converting liquid fuels to a blend of gases containing hydrogen and carbon monoxide as major components. More particularly, the present invention relates to a liquid fuel reformer apparatus that includes a regulator member whose effect is to facilitate the vaporization and reforming of liquid fuel introduced into the apparatus.
Fuels on board vehicles, for example, hydrocarbon mixtures such as gasoline or diesel fuel, military fuels such as JP8 or the like, or other fuels such as kerosene, biodiesel, alcohol or oxygenated fuels, generally include components of relatively low volatility. The combustion of liquid droplets of such fuels prior to their vaporization typically results in the formation of soot and coke as undesirable byproducts.
The use of a catalytic reformer to convert a liquid fuel into a gaseous fuel stream containing hydrogen and carbon monoxide as major components is known. However the injected liquid fuel is prone to be deposited on the walls of the reformer chamber, forming puddles that are difficult to vaporize or combust. This situation, which is especially likely to occur during cold start operation, results in the production of residues that present a challenge to the control of air:fuel ratios and are adverse to reliable long term operation of the reformer.
Increased volatilization and more complete combustion and/or reforming of the liquid fuel injected into a reformer reactor chamber would be highly desirable. These beneficial results are provided by the apparatus of the present invention.
The present invention is directed to a liquid fuel reformer apparatus that comprises a reactor tube having at a first end an injector for introducing droplets of liquid fuel and an inlet for introducing an air flow, and at a second end an outlet for discharging a reformate fuel stream. A reforming catalyst for converting the liquid fuel to the reformate fuel stream is disposed within the reactor tube, and at least one regulator member is disposed between the first end of the tube and the catalyst. At least a portion of the regulator member is permeable to liquid fuel and to air and vapor flow.
The liquid fuel reformer apparatus of the present invention can be applied to any liquid fuels commonly found on board vehicles, including, for example, hydrocarbon mixtures such as gasoline or diesel fuel, military fuels such as JP8 or the like, and other fuels such as kerosene, biodiesel, alcohol or oxygenated fuels.
Referring now to the drawings, which are intended to be exemplary, not limiting:
As already noted, when a liquid fuel that contains low volatility components is introduced into a reformer apparatus, there is a tendency for fuel droplets impinging on the reformer wall interior surface to agglomerate, forming puddles that resist vaporization and reforming. The reformer apparatus of the present invention, with its included regulator member, facilitates the reforming reaction by, for example, reducing the droplet size of the introduced fuel, diverting the fuel droplets from the reactor wall, increasing the flow velocity of the introduced air in the vicinity of the injected fuel, and improving the mixing of fuel and air.
Referring to
Disposed within reactor tube 11 is a reforming catalyst 18 for converting fuel and air to reformate fuel stream R, and a regulator member 19 that facilitates the vaporization and reforming of liquid fuel F is disposed between first end 13 and catalyst 18. Although only a single regulator member 19 is depicted in
Also shown in
Still another variant of the regulator member 19 generically represented in
Both of regulator members 319 and 419 would be expected to provide a significant increase in the velocity of the air passing through them, resulting in an enhanced fuel-air mixing rate. In addition, the surfaces of impermeable portions 320 and 420-421 of regulator members 319 and 419, respectively, that face catalyst 18 can be adapted to absorb thermal radiation from the catalyst, providing an efficient heat source for promoting the fuel-air reaction. If desired, any of the variants of regulator member 19 can also be adapted for external electrical heating, which is preferably applied to those portions that are permeable to fuel and air.
Although
While the invention has been described by reference to various specific embodiments, it should be understood that numerous changes may be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the described embodiments, but will have full scope defined by the language of the following claims.
