Low emissions catalytic combustion system

Claim 1

For use in a continuous combustion system having means for producing a primary stream of compressed relatively cool air to which heat and fuel is added to define a mixture for supporting combustion and thereby generating hot gases for driving a working element, apparatus for adding heat and fuel to the stream of compressed air comprising: a. means for adding fuel to said stream of air in a manner providing a homogeneous air/fuel mixture at a predetermined temperature for generating said hot gases, b. catalytic combustion means effective to sustain continuous, flameless oxidation of said mixture at a predetermined temperature, thereby generating said hot gases, c. heat exchange means for transferring heat from said hot gases to the stream of compressed air, said heat exchange means being comprised of a perforate rotating member having surfaces effective to contact separately both said hot gases and air stream during a single rotation for transferring heat therebetween, d. preheating means located upstream of said catalytic combustion means for raising the temperature of said mixture to said predetermined temperature in advance of sustained catalytic combustion by regulating said air/fuel mixture for supporting independent flaming combustion of said mixture upstream of said catalytic combustion means, said preheating means comprising a duct effective to separate a portion of said air stream and direct said portion through one radial region of said member, said preheating means being adapted to add fuel solely to said portion, said preheating means also having ignition means for igniting said regulated mixture and having control means for extinguishing said flaming combustion when said mixture attains said predetermined temperature for sustaining catalytic combustion, the ignition means being located proximate to at least one surface of said perforate member for igniting said mixture immediately downstream of said member.