The Pioche weekly record. [volume] (Pioche, Nev.) 1877-1900, 1884-08-09
TREATING REBELLIous ORES.
Chicago Mining Review

Ihe vast Importance CT some successful |
process of treating rebellious ore gives
every experiment in this direction un-
usual interest, and every operation is
eagerly scrutinized by practical and
scientific men whenever presented. For
some months Professor Cherry of Chicago
associated with number of prominent
capitalists, has been experimenting upon
system which he has invented for this
particular purpose. During the week an
experimental run was made with some
most rebellious and refractory ore, and
the result, we are pleased to note, indi-
Gates decided success. To better un-
derstand the process and method en-
ployed We will give a brief synopsis of
the operation as detailed by Professor
Cherry:
The furnace was charged with about
two and one-half tons of ore, which was
particularly sulphurous and arsenical in
its composition, the reduction of which
has been unsuccessfully attempted at
number Of different places. The appara-
tus used at present is an upright retort,
with capacity Of from two and half to
three tons. The ore is broken to the
size OF hickory nut Or finer if required.
The retort after charging is sealed so that
the air is excluded and the ore is treated
in a vacuum.
Heat is then applied to the outside of
the retort until a temperature OF 500 de-
grees is secured, indicated by pyrome-
ter inserted in the top of the retort.
When this degree of heat has been at.
tanned, superheated steam is forced into
the retort under a pressure Of from l5 to
% pounds, and uniformly distributed
through the entire mass. The steam in
the retort and the heat outside is contin-
ued until from 600 to $50 degrees of heat
are shown, when considerable part of
the sulphur will be thrown over and de.
posted as -four sulphur in vessel for
condensation.and precipitation. The cur
rent of superheated steam is permitted
to pass through the ore in the retort and
to escape through pipe provided with a
check valve, by which can be regulated
the pressure in the retort and the exit of
the liberated sulphur which is carried
over by the hydrogen into the stes n,
while the oxygen is taken up by the ore.
| This process is continued until the vapor
and steam escaping fail to show any odor
of sulphur, when, if the process has been
properly conducted, it will be found that
all the arsenic and sulphur will be sepa-
rated from the ore and deposited as solids
in the form Of -four sulphur and chloride
Of arsenic, which product may be utilized.
To further carry out the intent of this
deoxidizing and desulphurizing process,
and to iberate the minerals under treat,
ment from their inorganic constituents
with which they are combined in nature
as amorphous metalloids, and to free them
from their associations, current of su.
perheated air is at this point introduced
under pressure of 20 pounds, through
the same apparatus through which the
steam was injected, and forced through
the same mass of ore in the retort. 'Ii
is well known" Professor Cherry says
Sin metallurgy, that there are three OF
mere kinds of amorphous sulphur, also
phosphorus, in most Of the metalloids
The amorphous constituents, contained
in these ores, cannot be volatilized ane
carried over by the steam, so, in order tt
most thoroughly remove them, it is nee
essary to supply current OF superheatee
air. The oxygen of the air combine
} with the metalloids in their nascent con
dition, which produces a union or com
bination which effectually secures tn
separation desired" This current of al
} is also made use OF to replenish the par
italy treated ore with organic oxygen
| ord NAV ha continued until the ore