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Professor W. A. Bone [Feb. 27, 



The Combustion of Typical Gaseous Fuels, 



Now, whilst with coal gas, coke oven gas or water gas, it should 

 be easily possible, without regeneration, to obtain in a refractory 

 granular bed temperatures of up to at least 2000° C. (or say 

 3630° F.), with a low-grade producer gas, such as Mond gas, about 

 1500° C. (or say 2730° F.), would probably be the approximate 

 maximum without regeneration. But with some degree of heat re- 

 cuperation, which in large furnaces is quite practicable, still higher 

 temperatures would be attainable. 



Moreover, within the maximum limits, the heating with any kind 

 of gas is very uniform, economical, and controllable ; indeed the tem- 

 perature for a given furnace fired by gas of uniform composition is 

 chiefly controlled by the amount of gas burnt, or in other words, the 

 rate of heat development in the bed. And as for economy, tests made 

 about three years ago in Leeds under my supervision upon medium- 

 sized muffle furnaces convinced me that to maintain a given tempera- 

 ture between say 800 and 1400° C, a properly constructed " surface 

 combustion furnace " would require between 70 and 40 per cent only 

 of the gas used in an ordinary flame-heated furnace of the same 

 dimensions, and that the advantage in favour of " surface combus- 

 tion " would increase rapidly with the working temperature. 



This was confirmed by independent competitive trials carried out 

 in New York shortly after my lectures there in the autumn of 1911, 

 in which our surface combustion furnaces were pitted against the 

 best American types ; it was proved that in order to maintain a tem- 

 perature of 1400° C. we practically halved their gas consumption, 

 whilst to maintain 800° C. our consumption was about 0*7 of 

 theirs. 



Anyone who understands furnace design and construction will 

 appreciate the many difiiculties which are necessarily encountered in 

 applying a new and revolutionary idea of this sort to the firing of 



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