The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1917-09-13

importance that the metallurgical in
dustry Is intensely interested in learn
1 ing the correct answer to them. If it
is true that the process making use of
less than per cent of oil Is different
and, leads to a different result from
that obtained when using more than
l per cent Of oil, and If 1t is true that
, only by using less than l per cent of
oil can commercially satisfactory re-
suits be obtained, then the industry
must make up its mind either to use
that process and pay royalty upon it.,
or to do without it. If, on the other
hand, by using more than / per cent
of the oil the operator can procure
commercial results. he is apparently
free to do so. If by his use of more
than l per cent of oil his costs amount
to more than the royalty demanded by
the company owning the patents upon
the process which uses less than / per
cent of oil, the operator is free to
either reduce his costs by intensive
study of his problem, or reduce his oil
consumption and pay royalty. Many
operators believe that If they can pro-
duce commercial results now by the
use of more than l per cent of Oil,
they have every hope of So reducing
the cost by the practice of various
economies and the introduction of
improvements that the total expense
of the process will be no more than If
less than l per cent of oil were used.
Owing to the wide desire for a solu-
ton of these problems, l have been
asked to undertake an examination of
the records of the experimental and
practical work that has already been
carried out on the part of the prob
lem by means of which ores are treat.
ed by processes using more than pei
cent of oil and compare them with
the results obtained with the develop
ed processes where less than / pei
cent of oil is habitually used. To as
sist in the intelligent estimation OF
results and comparison of practice In
various plants, the operators of some
of the largest producers of copper
lead and zinc have permitted me to
examine the data obtained in the car
rying out of both of these processes
have been allowed to study much oil
the data obtained while working un.
der both sets of conditions and have
been enabled to study and discuss ex.
perimental results obtained while
working out tests in both ways. AL
these results are interesting and some
of them are remarkable. Unfortun.
ately, owing to the present state Of lit.
igation and the unwillingness, there.
fore, of the operating companies tt
allow their methods or results to be
made public, 1t is necessary for me tC
refrain from mentioning any Of then
definitely or making public any Of the
data that / have reviewed. can
however, give a review in summary oil
what is being done in the United
States and am able to set forth here
the import of the data l have beer
permitted to examine. shall take the
matter up first from the experimental
viewpoint, and then from the practi-
cal, plant operating point of view.
Treating the matter from the point
of view of the experiments that have
been made, it can be said that salts.
factory flotation results have beer
obtained in a great number Of in.
stances on a number of different kind.
of ore and at different places by the
use of more than / per cent of oil
The subject came UP during the dis
|cussion on flotation at the Februar!
meeting of the American Institute o
Mining Engineers, in New York, ant
the consensus of opinion there wa
that no one had been able to find an.
critical point in the amount of oil use,
below which extraction results wer
good and above which they were un
satisfactory.
In some cases the method of handl
ing the process differed widely fror
J the method followed when the smalle
Quantity of oil was used, while Il
J others no change was found necessary
The changes in methods Of handlin
involve sometimes the mixture Of tn
, oil with water, or the circulating sol
, ution, before adding 1t to the pulp, an
In other cases the larger quantity Q
oil may be added in regrinding ma
J chimes, where satisfactory mixture
!. may be obtained. Further, some in
! stances are pointed out where tn
character OF the circulating water ha
, to be radically changed before salts
factory results could be obtained b
the use Of the larger quantity Of oil
These points were pretty thorough