The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1899-11-28
THE WORK OF CONVERTING
Reducing Matte to Annode Plates
and Pig Copper.
THE PROCESS DESCRIBED
Two Hundred and Fifty Tons OF Copper
Daily-The Blast and Refining Fur
nacss-Engine and Boiler
Plant,

1t is no dispara cement of any other
reduction works to say that the great
converter of the Anaconda company is
the most interesting plant in the en-
TIRE state that is engaged in the treat
men1 or copper ores and matte The
operations of others are Just as i'm
portant in their way, but the OPERA
lions are far less attractive to the eve
and less startling in the rapidity and
character of the chemical changes
produced. True, there are other con-
verters, but they are upon a relatively
small scale, and there are features IN
possibly, at Great Falls
A converter plant, as is generally
known in this section, is for the pur-
pose Of converting copper matte which
usually carries about so per cent, Of
copper, into pig copper that is within
= or per cent. of being chemically
pure. But this plant goes a step fur
ther by reducing a portion of the cop
per to q still higher grade, in the form
OF annode plates for the refinery
Inc process of converting is, briefly.
this: The converter is large movable
iron vessel not unlike a huge jug open
at the top. This is lined with a thick
coatin of Well-ground silica, which con
sists mainly of oxygen. Into this con-
verter Is poured the molten matte,
which is from so to. say, SO or 81 per
cent: copper, perhaps 25 or 80 per cent.
sulphur, the remainder consisting OF
iron and other impurities.
Into this molten mass current Of
air is turned, the oxygen of which unit
ing with the sulphur Keeps up and even
intensifies the combustion, the oxygen
Of the air being reinforced from the
silica lining. When the charge has
reached certain stage indicated by the
color of the fumes and seething metal,
the converter is tilted over by ma
chinery, and the iron and other impure
matter floating upon the surface is run
off into pots, and, cooling, forms Stag.
When this is substantially all removed
forced draft Of compressed air is
turned on, and the sulphur itself is
blown away i'm the form of vapor or
fumes The copper remaining is then
drawn off into molds. and constitutes
what is commercially known as pig
or blister copper.
The Stag referred to contains a small
percentage of copper, and in order to
save this it is remelted in blast fur
naces. and goes again into the form
of matte. when the converting process
is repeated.
These works turn out something like
$50 tons of copper each "a hours OF
this about one-half is sent to Balti-
more in the form of pigs for refin-
ing, while the other half is remelted
in the fitting furnaces and then cast
INTO annode plates for refining here.
In the fitting furnaces the copper un-
dergoes some further chemical changes,
getting rid of small quantities OF for
eign matter, and being put into bet
ter shape for refining.
At this great plant there are 10 con-
verter stands, and four of the fitting
or refining furnaces. There are also
six blast furnaces, each of 200 tons q
day capacity, and there is well de-
fined rumor of two more larger ones
being built before long. The blast fur-
naces take the better class of ores, melt
them, run off much of the impure mat
ter and form matte, which Is then
treated in the converterS as described,
the Stag referred to being melted in
the blast furnaces alGng with the ore.
This plant is of necessity furnished
with great engine and boiler power, al
though the engines are not equal to.
those of the refinery. They consist of
one E. P. Allis, of 500 horsepower, one
Fraser and Chalmers of the same, five
Fraser and Chalmers of 200 each, one
Porter and Allen of $50 and Westins-
house of $50 horsepower. All but the
last named are air compressors, fur
nishing air to the converters. w..
The Westinghouse, which is separat-
ed from the others, runs the dynamos,
of which there are two each OF l0o kiio-
watts-a kilowatt of electricity being
CONTINUED on Page Fifteen).