COAL 



Coke 



Manufac- 

 ture. 



Two Qualities. 



Improved 

 Methods. 



Backwardness 

 of India. 



Loss of 

 Nitrogen. 

 Sulphate of 

 Ammonia. 



Recovery- 

 ovens. 



Sulphur. 



Literature of 

 Coke. 



THE INDIAN COAL INDUSTRY 



coking because they form a compact coherent coke, but mixtures of 

 caking and non-caking coal can be successfully carbonised. [Cf. Blount 

 and Bloxam, I.e. 83.] 



For many years past the Raniganj, Jherria and Giridih mines have 

 manufactured coke. Their output was in 1902 returned at 128,910 tons, 

 of which Raniganj produced 86,000 tons. Coke-making is a most im- 

 portant industry, and one in which the future will doubtless record much 

 progress. It means the profitable utilisation of coal waste, and the ac- 

 companying prosperity of the metallurgical industries. There are two 

 qualities, " hard " and " soft." Ward (Rec. Geol. Surv. Ind., 1904, 

 xxxi., 92 et seq.) has recently published an interesting paper in which 

 he urges the necessity of introducing improved methods of manufacture 

 of coke with a view to recover the valuable by-products presently being 

 wasted. Commenting upon this paper, Holland has explained that 

 the backwardness of India in this matter proceeds from the limited de- 

 mand for coke for metallurgical purposes. ; ' At present about 300,000 

 tons only of Indian coal are converted annually into coke, though a de- 

 mand will naturally increase with the development of metallurgical in- 

 dustries. Even as matters stand at present Mr. Ward has shown that 

 there is good ground for assuming that the additional outlay necessary 

 for closed ovens of the ' recovery ' as well as the ' non-recovery ' type 

 would be repaid. Assuming that the coal used for coke-making in India 

 contains on an average 0'75 per cent, of available nitrogen, the present 

 system of manufacture in open ovens means an annual loss of 2,250 tons 

 of nitrogen, sufficient that is for the manufacture of 10,613 tons of sulphate 

 of ammonia, which at 13 a ton is worth 137,969 or more than 20 lakhs 

 of rupees." As showing the full value of this contention it may be men- 

 tioned that it has been ascertained that Java imported in 1901, 21,700 tons, 

 and in 1902, 23,400 tons, of sulphate of ammonia to be used as a sugar 

 fertiliser. 



Experiments recently made on a large scale in Germany and America 

 have confirmed the conclusions referred to above with regard to the suita- 

 bility of Bengal coal for the recovery of ammoniacal by-products, and 

 arrangements are now well advanced for the erection of recovery-ovens 

 on the Giridih, Raniganj and Jherria fields. With a view to improving 

 the local market for the products, experiments are being conducted 

 by the Agricultural Department to test the suitability of ammonium 

 sulphate for Indian sugar-cane and other crops, whilst to meet the 

 probable demand for sulphur the Geological Survey has organised pros- 

 pecting operations on a large scale in connection with the copper sulphide 

 deposits known to occur within easy distance of the coalfields in Bengal. 



But to conclude these remarks on coke, it may be observed that so 

 much has been written on the subject that to give even the more 

 useful references would occupy much space. The Journal of the Society 

 of Chemical Industry teems with descriptions of methods, apparatus and 

 processes in all countries. Similarly, innumerable passages occur in these 

 journals on the distillation of coal ; on gas-making ; on the gaseous 

 products of coal ; on the relation of petroleum to the hydrocarbons of 

 coal ; on the influence of lime on coal ; on the determination of the nitrogen 

 in coal ; on coal-tar ; on ammonia, etc., etc., subjects intimately as- 

 sociated with the future of the Indian coal and coke supplies. [Cf. Weeks, 

 Man. of Coke, 1892.] 



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