A N T I M O N Y : ITS HISTORY, CHEMISTRY, MINERALOGY ...

98 THE METALLURGY OF ANTIMONY.
A / 2 j 9\ ff 2 i an ^ c > is changed into volatile oxide. The filtering
and condensing chambers may be connected with h.
The latest improvement in the volatilising process is embodied in
a patent* obtained by M. Herrenschmidt, with which the author
is personally familiar. The fundamental principle is the same as
that of his earlier patent, 1903; the only difference being in the
details, which are clearly shown in fig. 45, and Plate opposite p. 100.
The Herrenschmidt Process of Antimony Smelting. (1) Introduction.—The
present account is based upon a personal study of
the new process, and contains the results of a few experiments
carried out in the Laboratoire de recherches industrielles pour
tous minerais of M. Herrenschmidt, at Le Genest (Mayenne),
France, to whom all the credit is due. The experiments on the
volatilisation process, given in the patent No. 386,107 taken out
by M. Herrenschmidt April 5, 1908, in France, were carried out
by that gentleman and myself on the 24th, 25th, and 26th of
May 1908.
(2) Description of the Apparatus.—Fig. 1 of fig. 45 is a longitudinal
section. Fig. 2 is a cross-section along a h. Fig. 3 is a cross-section
along c d ef Fig. 4 is a horizontal section along J Y.
The broken mineral is charged, together with a certain percentage
of fuel, into the roasting furnace, a, the bottom of which is
formed by horizontal iron bars, 5, arranged symmetrically at even
distances apart.
The volatile antimony trioxide is deposited on condensation
pipes, e (Fr. tuyaux a ailettes), in the condensing chambers, d, by
the aid of the two ventilators, h.
The last trace of the uncondensed oxide is laid down by the water
coming from the coke-tower, i, at the top of which are the water-pipe,
j, and the see-saw water-distributor, Jc. The roasting furnace is built
partly of bricks and partly of cast metal; the condensing chambers
are all of cast-iron; and the coke-tower is formed of wood. Each
condensing chamber is 1 metre long.
(3) Description of the Process.— (a) The guaranteed results of the
apparatus just described are :—
The yield in oxide is never less than 90 per cent, of the metal
contained in the ore.
With ores direct from the mine, containing 10 to 15 per cent,
of antimony, 6 tons can be treated every twenty-four hours, with
a consumption of 4 to 5 per cent, gas coke or 6 to 7 per oent.
of charcoal.
* French patent granted April 5, 1908, No. 836,107.