The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1916-04-20
MAIN PROCESS FAILED
DROPPED BY B. H. & S.
AFTER EXPERIMENTS BELIEVE
PROCESS CAN NOT BE CON-
MERCiALIZED.

The Engineering and Mining Jour
nal has the following comment on {
process which for a time promised t
revolutionize methods Of mineral re-
covery from lead and zinc ores, anC
which now appears to have beer
abandoned as impractical on com.
mercial basis:
! About a year ago much interest was
excited by the news that the Bun,
ker Hill & Sullivan Mining and Con.
centrating company had taken up the
Malm process and was going to cree
| a plant to use 1t in connection witt
the treatment of its ores at Kellogg
Idaho. Since then but little has beer
heard about this subject and there
has been good deal of inquiry re.
speeding the results of the expert
mental work that was being conduct
ed on large scale. The following in
formation comes from an authorita
tive source.
The early experience of the Bunker
Hill & Sullivan company with the
Malm process extended over the per-
iod of about five months, and the lab
oratory tests indicated an astonish-
ingly high extraction of the lead, sill
yer and zinc of the slime tailings
from the concentrating mill, which
was the material tested and which 1t
was especially desirable to treat. Par
enthetically it may be remarked that
since then the company has been able
to recover the metals lost in that pro-
duct, to a large extent by the appi-
cation of the flotation process. Mr.,
Malm and his associate, Mr.. Ionides,
urged the purchase at foreclosure
sale of the equipment in their George
town plant That plant had not been
fully completed and had never been
run, not even in part. The whole
thing was taken to Kellogg, Idaho
and installed there in an unused por-
ton of the MILL it being turned over
to Mr. Malm on a monthly salary ar
rangement.
The first difficulty was found to bt
in performing the electrolytic decom.
position of fused zinc chloride for the
production of chlorine gas and metal.
! lie zinc. All demonstrations and thu
tests of the process had previously
been made with chlorine gas purchas
! ed in cylinders. Finally some mem.
bers of the Bunker Hill & Sullivan
staff constructed electrolytic zinc cells
according to their own ideas, which
they operated with a fair degree o.
success for about two months, pro-
ducing chlorine gas for continuance
of the experiments, together with me-
| tallc zinc, carload of zinc chloride
having been purchased for the pur.
pose of starting the cycle The Bun.
ker Hill & Sullivan metallurgical staff
is of the opinion that no one ever went
so far in the electrolysis of fused zinc
chloride as it did. The staff is now
strongly of the opinion that the pro-
cess can not be commercial one in
the hands of anybody.
There are many mechanical difficult
ties in the handling of the fused
chloride and in making a regular out
put of chlorine gas. The best that
could be done with the largest eel
constructed at Kellogg was a produc.
ton of about 200 pounds of zinc in "a
hours. The operation of a plant OF
any considerable size would require g
huge number of cells.
! In the trial of the Malm process al
Kellogg, neither the roasting nor the
lixiviation work was satisfactory. The
acid resisting filter failed, and the
plans for precipitating lead, and the
recovery of zinc chloride by building
up the sulphate to saturation follow.
ed by evaporation, did not work ou
at ALL There are considered to bt
some attractive things about the pro
cess, which, however, are regarded a!
not new. This has reference particu
larly to the reaction Of chlorine ga
on the dry ore.
The subsequent handling of the Xix
iviate and the regeneration Of thu
chlorine are the stages wherein tn
serious difficulties arise. The Bunke
Hill & Sullivan company abandoned
the Malm process during the fall o
1914, since which time 1t has been do
ing satisfactory work in a small wa.
by sulphate roasting, brine teaching
lime precipitation and electrolysis
The work with a chlorine process a
Helena, which was conducted alonl
lines similar to those of the Main
process, was equally unsuccessful.