Patent ID: 7220392

Claim:
A fuel conversion reactor comprising a shell-and-tube heat exchanger for heating a gaseous fluid prior to reaction with a fuel and for cooling a gaseous mixture produced by the reaction, said heat exchanger comprising: a primary shell member having primary and secondary ends and a sidewall extending between said ends and defining a heat exchanging chamber located within the shell member; an inlet for introducing said gaseous fluid into said heat exchanging chamber; a first tube sheet fixedly mounted on said primary shell member in the vicinity of said primary end and sealingly closing said heat exchanging chamber at one end of the chamber; a second tube sheet device which is separate from said primary shell member and is located in the vicinity of said secondary end, said second tube sheet device forming another end of said chamber that is opposite said one end of the chamber; and a plurality of heat exchange tubes extending from said first tube sheet to said second tube sheet device and rigidly connected to both the first tube sheet and the second tube sheet device, said heat exchange tubes providing passageways for said gaseous mixture to flow inside the tubes through said heat exchanging chamber; wherein one or more outlet apertures are formed in the region of said secondary end of said primary shell member in order to provide at least one outlet for said gaseous fluid which flows through said heat exchanging chamber on a shell-side thereof during operation of said fuel conversion reactor; wherein said second tube sheet device includes a secondary shell member having a peripheral sidewall, a first end located adjacent to said secondary end of the primary shell member and a second end spaced from the first end; wherein the secondary shell member and the secondary end of the primary shell member together form a disconnected joint; and wherein said second tube sheet device is free to move relative to said primary shell member upon thermal expansion of said heat exchange tubes.