November 10, 19112] 



SCIENCE 



551 



DIVISION OP GAS AND TUEL CHEMISTRY 



A. C. Fieldner, chairman 

 E. S. McBride, secretary 



Chemistry of combustion: W. K. Lewis. The 

 present state of knowledge of combiistiou is re- 

 viewed, the field being divided into, first, com- 

 bustion within the fuel bed; second, distillation 

 of the volatile matter in the fuel; and, third, the 

 burning of the combustible gases over the fuel 

 bed. The composition of 'the gases within the 

 fuel bed is discussed and the effect of increased 

 rate of combustion shown. The velocity of the 

 reaction of C plus Oo equals- CO2 is shown to be 

 dependent on the speed of diffusion and not on 

 the specific reaction rate. The modern concepts 

 of tlie combustion of hydrocarbons are also dis- 

 cussed. 



Combustion of powdered coal: Henry Kkei- 

 SI>Jgeb and John Blizaed. This paper considers 

 essential factoi-s in burning powdered coal, and 

 gives a review of some tests carried out by the 

 U. S. Bureau of Mines and the Combustion En- 

 gineering Corporation. The size of the particles, 

 their motion relative to the surrounding air and 

 methods of bringing them into contact with fresh 

 supplies of air as they burn are discussed. A 

 furnace and burner designed for burning pow- 

 dered coal are shown and the principles of the 

 design explained. The principal results of tests 

 carried out on a large boiler are shown gi'aph- 

 ically. 



Simultaneous combustion of CO and hydrogen : 

 R. T. Haslam. a review of the literature shows 

 that doubt exists whether the combustion of hy- 

 drogen and carbon monoxide is of the second or 

 third order. Experimental evidence is offered to 

 show that when carbon monoxide and hydrogen- 

 burn simultaneously witli oxj-gen in free space 

 the combustion reactions are both trimolecular 

 and that the ratio of the reaction velocity con- 



d 



staiits in the equation —(00) = iii(C0)2(0,) 



dt 



d Ici 



and — (H2) = E2{B..,y-(0.2) is — = 0.35. 

 dt JTo 



Some aspects of combustion of gases: Henry 

 L. Bead. 



A study of the water gas reactions: E. T. Has- 

 lam, P. L. Hitchcock and E. W. Eudow. The 

 action of steam on carbon through the tempera- 

 ture range of 650 degrees centigrade to 1200 

 degrees centigrade was studied by means of vai-y- 

 ing the pressure of the steam and results indi- 

 cated: First, that below 900 degrees the major 

 reactions are (B) C plus 2H2O equals COo plus 

 2H2; (B) plus CO2 equals 2C0; whereas above 



900 degrees the reactions are (A) plus H,0 

 equals CO plus H, ; (B) C plus 2H2O equals 

 CO2 plus 2H^; (D) C plus CO2 equals 2C0; sec- 

 ond, that the uudecomposed steam is shown to be 

 tlie controlling factor in the CO and CO, ratio 

 rather than the temperature at which reactions take 

 place; third, equations are given showing the per 

 cent, of CO2 as a function of the uudecomposed 

 water; fourth, considering the rate of reaction (B) 

 as unity it was found that (A) at temperature be- 

 low 900 degrees centigrade reaction (A) is prac- 

 tically non-existent and that the velocity constant 

 of reaction (B) is 2.0; (B) at temperature above 

 900 degrees the velocity constant of reaction (A) 

 is 1.0 and that of (D) is 2.18. 



Producer gas reactions: W. K. Lewis. Appli- 

 cation of equations in previous article (water gas 

 reactions— Haslam, Hitchcock and Eudow) show- 

 ing effect of temperature, steam-air ratio and 

 time of contact on composition of producer gas. 



The combustion of gaseous fuels: C4eorge F. 

 itouLTON. Gas fuels commonly distributed for 

 domestic and industrial purposes by gas compa- 

 nies vary in heating value from 4.30 to 1,100 

 B.T.U. per cubic foot. These gases vary in spe- 

 cific gravity from 0.35 to 0.70, and the pressures 

 at wliich they are delivered to the consumer's 

 aippliance vary from 2 to 12 inches of water. 

 The result of tliese large variations in heating 

 value, specific gravity and pressure is that the 

 manufacture of efficient gas appliances has been 

 greatly retarded; the knowledge of correct ad- 

 .justment of appliances is very vague, and modi- 

 fication of existing standards of quality has been 

 made difficult because the effect of these changes 

 on quality of service, efficiency of utilization and 

 safety of operation has been difficult to deter- 

 mine. The range of operation of burners as well 

 as the efficiency that can be secured will depend 

 primarily on the characteristics of the flame. 

 Tins paper shows how these flame characteristics 

 are modified by a change of injection of primary 

 air which may be caused by variations in gas 

 rate, pressure, composition of gas, etc. 



Combustion in engine cylinders: H. C. Dick- 

 inson. The process of combustion in engine 

 cylinders presents some very interesting problems 

 which demand a radical departure from the usual 

 methods of reasoning and experiment. When a 

 combustible mixture of gases burns at constant 

 volume no two successive portions of it are burned 

 at the same pressure or the same temperature or 

 at the same time. The reactions do not take 

 jilace .simultaneously throughout the mass and the 

 hiw of mass action does not apply, except to 



