10 MANUFACTURE OF AMMONIA 



from other similar coking ovens. The condensable con- 

 stituents of the coal gas are removed before it is consumed as 

 fuel. The proportion of ammonia recovered in this process is 

 very similar to that obtained in a gas works, and amounts to 

 about 22 Ibs. of sulphate per ton of coal. The recovery of the 

 ammonia during the process of coking has made as yet but 

 limited progress, owing to the much greater expense of the 

 plant required when the new method is adopted. Any rise in 

 price of ammonia salts, or tar products, would be followed by 

 a great increase in the output of ammonia and tar in the 

 manufacture of coke. 



Large quantities of .coal are consumed in the blast-furnaces 

 of iron foundries. A successful attempt has been made to 

 collect the gas evolved on the entrance of coal into the furnace, 

 and to recover the ammonia which it contains. The yield of 

 sulphate of ammonia is similar to that obtained in coking 

 operations. 



The distillation of bituminous shale in Scotland for the 

 production of paraffin, furnishes a considerable quantity of 

 ammonia. The proportion of the nitrogen obtained as am- 

 monia is very similar to that yielded in the distillation of coal. 

 Of 100 parts of nitrogen in the shale, 63 remain in the coke, 

 20 are found in the tar products, and 17 are obtained as 

 ammonia. 



The quantity of sulphate of ammonia produced in the 

 United Kingdom has rapidly increased in recent years, and 

 the production is capable of much greater development if the 

 demand for the article should increase. The total production 

 in the United Kingdom was in : 



1870, 40,000 tons 



1875, 46,000 ,, 



1880, 60,000 ,, 



1885, 97,000 



Since 1886, the Inspector of Alkali Works has published in 

 his Annual Report a detailed account of the amount obtained 

 from each source. Each year shows an increase in the total. 

 The amounts produced in 1886, 1890, 1894, and 1897 were as 

 follows : 



