Apparatus for the conversion of hydrocarbons

Abstract

The invention relates to an apparatus for the conversion of hydrocarbons to hydrogen, and to the conversion process. Fuel processors, or reformers are often used for large-scale conversion of natural gas to hydrogen containing mixtures. Although large fuel processors perform well, small reformers still have some major drawbacks. The object of this invention is to provide an apparatus for the conversion of hydrocarbons to hydrogen rich gas mixtures, that operates at a relatively low temperature, uses air instead of pure oxygen, can be operated at atmospheric pressure, has a low pressure drop, is compact, has low thermal mass and having high thermal efficiency.

What is claimed is:  
     
         1 . A system for the catalytic conversion of hydrocarbons to hydrogen containing mixtures comprising, radiation shielding, heating of the incoming gasses and cooling of the converted gasses, and heat exchange characterized in that radiation shielding, heating of the incoming gasses and cooling of the converted gasses, and heat exchange are integrated in one apparatus.  
     
     
         2 . An apparatus according to  claim 1  wherein means for insulation against thermal conduction is integrated.  
     
     
         3 . An apparatus according to any one of the preceding claims wherein the catalytic conversion of CO to CO2 is integrated.  
     
     
         4 . An apparatus according to any one of the preceding claims being part of a fuel cell system, wherein an after burner for the hydrogen containing exhaust gasses coming from the fuel cell stack is integrated.  
     
     
         5 . An apparatus according to any one of the preceding claims wherein the catalyst for the last conversion reaction is in the out going gas channel of the converted gasses.  
     
     
         6 . An apparatus according to any one of the preceding claims wherein the gas conversion reactor or reactors and heat exchangers have the shape of a spiral.  
     
     
         7 . An apparatus according to claims  6  wherein consists of 3 channels that are separated by blades.  
     
     
         8 . An apparatus according to any one of the preceding claims wherein the air channel has a dead end and the air has to flow trough a porous material to one or both of the other gas channel.  
     
     
         9 . An apparatus according to any one of the preceding claims wherein the porous material contains a suitable steam reforming catalyst.  
     
     
         10 . An apparatus according to any one of the preceding claims wherein the in the porous material H2 and CO react with oxygen generating H2O, CO2 and heat.  
     
     
         11 . An apparatus according to any one of the preceding claims wherein the flow control of the gases is based on temperature measurement in the fuel processor.  
     
     
         12 . An apparatus according to any one of the preceding claims wherein the flow control of the gasses is based on temperature measurement in the afterburner.  
     
     
         13 . An apparatus according to any one of the preceding claims wherein the reactor is made of thin metal sheet.  
     
     
         14 . An apparatus according to any one of the preceding claims wherein the reactor walls have a thickness between 25 and 500 micron.  
     
     
         15 . An apparatus according to any one of the preceding claims wherein the reactor walls have a thickness between 49 and 126 micron.  
     
     
         16 . An apparatus according to any one of the preceding claims wherein the inner walls of the spiral shaped blades are coated with a suitable catalyst.  
     
     
         17 . An apparatus according to any one of the preceding claims wherein the inner walls of the fuel channel is coated with a catalyst like koper, koperoxide, koper on zinc oxide, koper on cerium oxide or platinum on a suitable carrier.  
     
     
         18 . An apparatus according to any one of the preceding claims wherein the inner walls of the channels are coated with a catalyst or a catalyst on a suitable carrier, and the amount op catalyst applied, and the composition of the catalyst is adjusted depending on its position in the reactor.  
     
     
         19 . An apparatus according to  claim 13  wherein the thin walled reactor is places in a chamber having the same or approximately the same pressure as the pressure inside the thin walled reactor, and the pressure outside this chamber is substantially higher than the pressure inside this chamber.  
     
     
         20 . An apparatus according to  claim 19  wherein there is a pressure leveling connection between the inside of the thin walled reactor and the surrounding chamber, this connection being preferably between the inlet of the air channel and the surrounding chamber.  
     
     
         21 . An apparatus according to any one of the preceding claims containing means of heating the center of the spiral for startup.  
     
     
         22 . An apparatus according  claim 16  wherein an electrically heated element is used for start up, and the heating element is placed outside the gas channels in the hard of the spiral.  
     
     
         23 . An apparatus according to  claim 17  wherein the heating element is a hot wire that is coated with a suitable catalyst, and is placed inside a gas channel  
     
     
         24 . An apparatus according to any one of the preceding claims wherein the pressure drop of the gasses inside the reactor is less than 100.000 Pa  
     
     
         25 . An apparatus according to any one of the preceding claims wherein the pressure drop of the gasses inside the reactor is less than 10.000 Pa  
     
     
         26 . An apparatus according to any one of the preceding claims wherein the pressure drop of the gasses inside the reactor is less than 1.000 Pa.  
     
     
         27 . An apparatus according to any one of the preceding claims wherein the pressure drop of the gasses inside the reactor is less than 100 Pa.  
     
     
         28 . An apparatus according to any one of the preceding claims, being part of a fuel cell system for micro co-generation, wherein cooling the outer wall with incoming cold tap water reduces heat leakage.