Method of cooling coal fired furnace walls

Abstract

A unique method of cooling the interior wall surfaces of gas-fired or coal-fired furnace combustion chambers using carbon dioxide from stack emissions is presented. Carbon dioxide is passed through a tubular structure fixedly attached to the furnace exposed fire-box refractory brick lining heated surface. Carbon dioxide passing through the tubular structure convectively absorbs heat passing through the tube walls of the said tubular structure thereby maintaining the furnace fire-box wall structural integrity at a safe operating temperature. The carbon dioxide exits the tubular structure at an elevated temperature and is collected in a thermally insulated collector manifold for catalytic reaction with high temperature steam and further processing.

1 . The use of gaseous carbon dioxide as a coolant media in a furnace fire-box, a refractory brick structure lining the interior surfaces of the said furnace fire-box, a plurality of ceramic pieces mounted on the vertical surfaces of said refractory brick structure, said ceramic pieces holding and providing support and spacing for a plurality of vertically aligned cooling tubes, gaseous carbon dioxide coolant flowing through said cooling tubes, said cooling tubes in communication with a manifold, said carbon dioxide flowing in said cooling tubes exiting the said furnace fire-box passing into said manifold.  
   
   
       2 . A furnace fire-box, said fire-box being lined with a refractory brick structure, a plurality of ceramic pieces mounted on the vertical surfaces of said refractory brick structure, said ceramic pieces holding and providing support and spacing for a plurality of cooling tubes, water entering said cooling tubes at the lower end of the said fire-box and exiting the said fire-box at the upper end, said ceramic pieces also holding and supporting a second row of cooling tubes at alternate positions between said water cooling tubes, carbon dioxide coolant flowing in the said second row of cooling tubes, said second row of tubes in communication with a thermally insulated manifold, said carbon dioxide flowing in said second row of cooling tubes exiting said furnace fire-box and passed into said thermally insulated manifold.  
   
   
       3 .  Claim 2  in which the said water cooling tubes and said carbon dioxide cooling tubes are supported at their upper ends by a ceramic mounting and at their lower ends by a lower ceramic mounting.