i hagey'ge | Sopa ]| 
NATURE 
463 
THE MANUFACTURE OF NITRATES FROM 
THE ATMOSPHERE.* 
Gee. 4 that it is only about ten years 
ago that the manufacture of nitrogenous pro- 
ducts by electric power was proved to be commercially 
possible, the progress has been remarkable; indeed, 
this metallurgical development of electric power 
promises to be even more important than electric 
traction. 
One ‘source of fixed nitrogen is sulphate of 
ammonia from gasworks, &c., and the production in 
this country in 1910 was 367,587 tons, which was 
26 per cent. more than in 1906. The principal in- 
coke | 
creases between 1906 and i910 were: from 
ovens, I15 per cent., and from producer-gas plants, 
50 per cent. The main source of nitrogen is nitrate 
of soda from Chile, and in the year 1911 the total 
export was 2,420,400 tons. 
Against these figures, the output of calcium nitrate | 
and calcium cyanamide, which are two of the main 
products of the electric fixation of nitrogen processes, 
are still small; but the important thing to notice is 
that electrical processes are now on a sound com- 
mercial footing, and very large extensions of plant 
have been recently 
made in Norway. 
Table I. gives 
particulars of the 
installations for 
the manufacture 
of calcium nitrate 
by the direct pro- 
eieiss, of Prof. 
Birkeland and 
Mr. Sam _ Eyde. 
It will be noticed 
that, although the 
first experimental 
plant was started 
only nine years 
ago, already the 
company control- 
ling the Birke- 
land-Eyde patents 
have installations 
aggregating 
209,000 horse- 
N 
Ny 
ye 
N 
N 
N 
N 
N 
N 
N 
N 
N 
N 
BS) 
Yoke of Magnet 
Fic. 1.—The Birkeland-Eyde furnace. 
power at work, and probably by 1916 another 300,000 | 
horse-power will be at work. 
Taste I.—Installations of the Norwegian Hydro- 
Electric Nitrogen Co. 
Year Horse-power Name of Installation 
1903 25 (Experiment) Frognerkilens 
1903 160 (Experiment) Ankerlokken 
1904 660 Arendal 
1905 45,000 First Notodden (Svaelgfos) 
1910 15,000 Second Notodden (Lienfos) 
1912 140,000 First Rjukan installation 
The other electrically produced nitrogenous manure, 
calcium cyanamide, is made by a more indirect 
method invented by Dr. Franck and Dr. Caro, and 
its manufacture is not confined to Norway. 
Table II. gives the principal installations, and it is | 
of interest to note that, although the first one on a 
commercial scale was erected at Piano d’Orto, in 
Italy, only eight years ago, there are works in opera- 
tion, and being built, which by the end of next year 
1 Abridged from a paper read before the Royal Society of Arts on May 15 
by Ernest Kilburn Scott. 
NO. 2227, VoL. 89| 
will be making calcium cyanamide at the rate of 
more than a quarter of a million tons per annum. 
Taste II.—Installations for Manufacture of Calciwm 
Cyanamide by the Franck and Caro Process. 
| Output 
Name of Company | Place of Installation _ per ann. 
| in tons 
| | 
Nitrogen Fertilisers Co. (North- | | 
Western Cyanamide Co.) Odda, Norway.. .. 15,c00 
5 ey re Alby, Sweden... .../ 15,000 
Societa Italianadi Prodotti Azotate | Piano d’Orto, Italy...) 4,000 
Societa Italiana per il Carburo di 
Calcio Raussen.) |LeLni ltaly «++| (5,000 
Societa Piemontese per il Carburo | 
di Calcio ... eae i) eee [oan Maxcelsltaly 3,000 
Société Frangaise pour les Pro- 
duits Azotes Martigny, Switzerland) 7,500 
Ar =n aH Notre Dame de Brian-! 
con... 7,500 
Bayerische Stickstoff Werke 
Ost-Deutscher Stickstoffcalf und | 
Chemische Werke... ... . 
A. G. Stickstoffdunger ..... 
Societa per l’Utilizzazione delle 
Forze Idrauliche della Dalmazia 
Trostberg, Bavaria | 15,000 
Bromberg, Prussia ...| 2,500 
| Kmapsack, Germany,. 18,000 
| 
Selenico, Dalmatia ...| 4,000 
Dugirat, near Almissa|8o0,000, 
Kinzei, near Osaka...) 4,000 
Nashville, Tennessee.| 4,000 
Niagara .+.| 12,000 
» » > 
Japanese Nitrogen Products Co... 
American Cyanamide Co. ... 
” ” 
The Nitrogen Fertilisers Co., which owns the Odda 
and Alby Works, works under licence from the 
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Fic, 2. 
North-Western Cyanamide Co., which company 
controls this country, Norway and Sweden, Belgium, 
and all the British colonies, protectorates, and 
dependencies, except Egypt and Canada. The Odda 
factory is now being enlarged, and at the beginning 
of next year will be producing 73,000 tons per 
annum. 
In the United States, the American Cyanamide Co. 
is about to erect a works in Alabama to manufacture 
24,000 tons per annum. . 
Birkeland-Eyde Furnace. 
This furnace, invented by Prof. Birkeland and Mr. 
Sam Eyde, of Norway, depends on the interaction of 
an alternating-current arc in a constant magnetic 
field. The furnace, as installed at Notodden, consists 
of a circular sheet-steel drum about 8 ft. in diameter 
and 2 ft. wide, lined with refractory firebrick, and 
having a disc-like space in the centre 6} ft. diameter 
and 11 in. wide. Air is supplied at the centre of the 
furnace by a Root’s blower, whilst a channel round 
the periphery of the disc space carries off the gases 
and unoxidised air, as shown in Fig. 1. 
Two electrodes, one of which is shown in Fig. 2, 
project into the centre of the furnace, and are 
approached to within about % in. They are copper 
tubes 14 in. diameter and % in. thick, and have water 
circulation to keep them cool. ' 
The points of the electrodes are in a magnetic 
field of about 4500 lines of force per square centi- 
metre. Alternating current at 5000 volts and fifty 
periods per second is supplied to the electrodes, whilst 
