CATALYSIS AND CATALYSTS 



211 



of a boiler of about ten times its capacity by the Skinningrove 

 Iron Company, Ltd., to be fired by the waste gas from an Otto 

 by-product coking plant. The boiler is shown in the illustration. 

 It consists of a cylindrical drum 10 feet in diameter and 4 feet 

 from back to front, traversed by 110 steel tubes 3 inches in 

 diameter packed with granular :efractory material. In front of 

 the boiler is a specially designed feeding chamber which delivers 

 washed coke-oven gas under a pressure of 1 to 2 inches of water. 



FIG. 58. EXPERIMENTAL TUBULAR BOILER FOR SURFACE COMBUSTION (BONE). 



This gas with a regulated supply of air is drawn, by suction 

 from a fan, through a short mixing tube, into each of the com- 

 bustion tubes, where it burns without flame. The products of 

 combustion pass outwards into a semicircular chamber at the 

 back of the boiler, and thence to the tubular feed-water heater. 

 The fan, which is attached just beyond this heater, is driven by 

 an electric motor, sucks out the cooled products at a temperature 

 of 100 C. (212 F.) or under and discharges them into the 

 atmosphere. 



A second kind of arrangement provides for the use of liquid 



