REFINING OF COPPER AND LEAD. 



COST PRICE OF REPINING COPPER BY ELECTRICITY. 



231 



ments which constitute the cost of the electrolytical refining 

 of copper, and their true interest consists in the comparison 

 which they allow of being established between various factory 

 installations. 



The cost of fuel in Birmingham is much lower than that 

 which we have taken as a basis ; but taking it at 6 francs per 

 ton at the works we find that the motive power still costs 1-20 

 franc per hour, or 125 francs per ton of copper. If we leave all 

 the other figures unaltered we obtain a total of 306 '45 francs, 

 that is to say, a much greater expenditure than at the Hamburg 

 factory. The interest on the capital engaged represents a small 

 proportion only of the cost price, whereas at Hamburg it con- 

 stitutes the main expenditure. 



As it was easy to foresee, two factories, those of Hamburg 

 and Marseilles, established with the same elements and on the 

 same- lines, give essentially different results in their working, 

 owing to their respective magnitude. At Hamburg, where the 

 operations are conducted on a large scale, the cost price of 

 refining is about 200 francs, whereas at Marseilles, where the 

 works are not of much importance, this cost is nearly doubled. 

 The arrangement of 120 baths in tension and the considerable 

 surface of anodes is much to be preferred to that of 48 baths of 

 small surface, notwithstanding the enormous capital sunk in the 

 first case. 



If water, instead of steam power, were used, it would still be 

 necessary, for economically refining the copper, to adopt the 

 disposition in use at Hamburg. 



The work obtained from a water-wheel or from a turbine is 



