354 



ILLINOIS STATE ACADEMY OF SCIENCE 



By way of illustration taken from some of our ex- 

 periments : Here is a high volatile eastern coal with ex- 

 cellent coking properties. It has in its normal condi- 

 tion a hydrogen-oxygen ratio of 73 per cent. Now by 

 saturating with oxygen under suitable conditions where- 

 by it has taken up approximately 50 times its volume of 

 oxygen, it has a hydrogen to oxygen ratio of 33 per cent, 

 and has dropped out of the coking class absolutely as 

 we would expect. By suitable procedure, however, and 

 recognition of the part that the cellulosic residue may 

 play in the carbonization process, it is possible to pro- 

 duce a normal coke even from this highly oxygenated 

 sample which, as we have seen, was reduced in its H :0 

 ratio from 73 to a percentage of 33. 



LOW TEMPERATURE CARBONIZATION 



Space will not permit of details in connection with 

 the behavior and control of these factors. One point of 

 fundamental importance and interest must suffice. It 

 relates to the property of all coals in general and high 

 oxygen coals in particular of decomposing with the evo- 

 lution of heat. The interactions involved, therefore, 



BOO 

 700 



200 





Z ■^ 6 a 10 JZ 14. /6 la F.0 ZZZ4 Zb ZQ20 3Z 34 



time: I h Nou/?s 

 Fig. 12. Progress of Temperature Changes in By-Product Oven. 



which it is essential to control, are exothermic in char- 

 acter. This fact should be coupled with another im- 

 portant one, namely, the control of these interacting 

 substances can best be carried out imder low tempera- 

 ture conditions of carbonization, that is, at temperatures 

 below approximately 750 deg. C. (1382 deg. F.). 



