The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1923-03-08

ItefeStlng paper was read 10y Howard
H. Fields. field manager of the Amer
lean Smelling 4 Refining company
on the Coolbaugh process for the
treatment of complex lead-zinc ores.
from which the following extracts are
taken:
Plant at Durango.
1--WE feel the most interesting event
of the year has been the building of
the sulphating plant-probably better
known as the Coolbaugh--at Durango.
The process promises SO mucn for the
mining of complex ores that short
history to date may be interesting.
"Messrs Coobaugh Read and Fish
err developed the sulphatng idea TO a
point where they interested Gen.
lRrclley Wells and associates. who
carried it to semi commercial stage
81 this point the American Smelling
& Refining company was asked TO in
vestigate it and did so thoroughly
our engineers and metallmgists
were convinced of the value of tho
process and today the Complex Ores
Recovery company composed OF the
investors General Wells and associ-
ates, and the smelling COMPANY is
building the first unit Of the plant az
a cost Of more than $3.50 600, to try
the process on a commercial scale.
The Process Explained
THE process itself is simple The
finely srushed ore or concentrate is
roasted i'm skinner multiple hearth
furnace, with the roast so controlled
that the metals are converted TO sui
pilates. The hot calcine from the fur
mace is then leached with water and
agitated. while the balance Of the sui
pilates and other elements in the ore
are not
Lime or zinc oxide is added to the
agitated solution and the soluble
copper precipitated as copper oxide
with the balance of the residue
1.-THE zinc sulphate which is the
only soluble compound left, is filtered
ffand the residue, containing all the
gold. silver lead and copper with
little zinc. is ready to be agglomerat
ed on the Dwight-Iloyd sntering ma
chimes The resulting product is then
smelted in the regulation lead blast
furnace.
"The solution containing the zine
sulphate is treated in spray dricr.
where the zinc sulphate crystallizes.
This method of crystallzing zinc sui
phate produces a sulphate containing
only two molecules of water of ciys
Utilization in place Of the normal sew
en- which is a saving of 10 to 20 per
cent when the shipment of zinc sui
plate is considered.
present plans assume that this
zinc sulphate viii be marketed as
such, but of course. tests now being
carried on may determine other forms
of zinc which can be produced and
sold
1.-THE first unit has a capacity of 10
tons Of concentrate. which will come
from the Black Bear mine at Tellu-
ride; but subsequent tests give hope
that the actual tonnage may be so
per cent greater
wrinkles in the process. which al
this time seem very improbable will
be ironed out and recoveries and costs
will be determined The new plant
will he in operation in May next.
The Miner and His Ore.
Naturally the miner will want to
know how this Will affect his own in
iividual ore We are not able to
make any blanket statements on its
universal application but about the
middle of the year we will be ready
20 look into its applicability to other
ores and concentrates.
"rhe probable procedure will be for
he interested miner 10 send small
sample to the testing laboratories
where preliminary tests on his ore
will be made
'If these are successful trial ship
nent of so or several hundred tons
viii be arranged. the quality not yet
actually determined but enough for
-eaI run. will be sent to Durango to
De purchased on a basis to be deter
mined later and the use of the Blacl;
Bear ores win be discontinued until
trial run is made.
"This will actually determine the
and costs on each individ-
nal ore and will be the basis for fl;
ure purchase if successful. Event
ialIy. of course. as enough ores are
-ound the plant will be enlarged to
accommodate them
at is impossible to predict the fir
lncial basis on which ores will be
purchased for treatment under this
'ulphating process until cost figures
rom actual operations are available.
However we hope to be able to
place zinc in the credit class. when
,ver the ore is adaptable for treat
nent by the sulphating process This
s d step in the right direction and
should make available many complex
,res which now can not be mined and