IMPROVEMENTS IN THE SMELTING OF COPPER, AND IN APPARATUS TO BE USED THEREIN
Year: 1869

page_text: LETTERS PATENT to Hunter Henry Murdoch, of No. 7, Staple Inn,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN THE SMELTING OF COPPER, AND IN APPARATUS TO BE
USED THEREIN."-A communication from abroad by John Dixon, of
Kapunda, South Australia.
Sealed the 20th July 1869, and dated the 23rd January 1869.
PROVISIONAL SPECIFICATION left by the said -Hunter Henry
Murdoch at the Office of the Commissioners of Patents, with his
Petition, on the 23rd January 1869.
I, HUNTER HENRY MURDOCH, of No. 7, Staple Inn, in the County of
Middlesex, Patent Agent, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE SMELTING OF COPPER, AND IN APPARATUS
TO BE USED THEREIN," to be follows:-
In reducing regulus by the pneumatic method great difficulty has
hitherto been experienced in applying the blast, the pipe or tuyere for
which being subjected to extremes of temperature is liable to fly to
pieces or become otherwise damaged.

page_text: Now the objects of this Invention are to remedy the above defect, and
under some circumstances to carry on the fusion of the ore continuously
with the reduction of the regulus obtained thereby. These objects are
accomplished by means of an improved form of blast furnace similar to
an ordinary ironfounder's cupola furnace, with the exception that a high-
pressure blast is used and distributed in a zone or belt all round the
furnace just above the cupola part by means of numerous air passages
or tuyere holes made through the lining of the furnace at an angle to
the horizon, instead of a low-pressure blast being introduced through
one hole as in the ordinary cupola furnace. The tuyere holes are
supplied with air by means of an air channel running round the exterior
of the furnace and communicating with the said tuyere holes, into which
channel air of the required pressure is forced. The said furnace is
formed of fire-brick or fire-clay surrounded by iron casing, that part of
the fire-brick or clay lining through which the tuyere holes pass being
made thicker than the other parts in order to allow for the wear
occasioned by the fluxing action which is energetic at that part. A
backing of sand is interposed between the fire-brick or clay lining and
the iron casing aforesaid in order to allow for expansion. The upper
part of the furnace carries a feeding platform, a tunnel head being built
on the said upper part in order to protect the workman from the sul-
phurous fumes given off. A tap-hole may, if required,' be made in that
part of the furnace containing the tuyere holes in order to tap out the
slag as it collects there. The lower or cupola part of the furnace is
furnished with a tap-hole through which the reduced copper is run out.
The furnace may be built on the ground or it may be made in two parts,
the upper part being supported by three or more pillars, and the lower or
cupola part being bolted to the said upper part so as to be capable of
removal therefrom for repair.
In smelting or reducing copper regulus according to my Invention I
gradually heat the furnace herein-before described with coke in the
usual way. I then take a quantity of regulus which I estimate will
contain as much copper as will nearly fill the cupola part of the said
furnace, and break the said regulus into small pieces. Having pre-
viously ascertained the proportion of iron in the said regulus, I take
from half to three quarters of its weight of moppa or other sand or
silicious matter, and knead it up with tar or other tenacious combustible
into convenient balls or cakes and throw them onto the coke in the
furnace, and as quickly as possible afterwards pile the regulus over it;

page_text: or the said charge may bo divided into two or more equal parts, and tho
first part after being thrown on may have a layer of coke thrown on
after it, and then the remaining, parts or parts of regulus, so that a pilo
may be formed of coke, sand, and regulus, coke, sand, and regulus, and
so on. This will allow the charge to be properly and quickly melted,
and prevent it from chilling the furnace. I then gradually increase the
blast so as to melt the charge as quickly as possible without blowing
out the coke, the regulus being allowed to rise over the ends of the
tuyeres. Instead of the sand aforesaid being added at the time of
charging the furnace, the said sand may be blown in with the blast from
a closed reservoir conveniently placed outside the furnace and furnished,
with a pipe and two stop-cocks, one to supply and the other to discharge
said sand into the blast pipe, and the said sand must be blown in as soon
as the said charge rises above the tuycres. As the lining of the furnace
unites more or less with the slag formed and tends to thicken it, and as
the success of the process depends greatly upon getting a fluid slag, the
usual means of reducing the quantity of sand or silica and adding lime
or other substance having the same property of thinning the slag must
be adopted. Immediately the air is blown through the charge vivid and
violent action begins and volumes of sulphurous acid are given off.
As soon as such action ceases I tap out. If the furnace be furnished
with two tap-holes I first tap out the slag from the upper one and then
tap out the copper from the lower one. If however the furnace have
but one tap-hole I first tap out the copper, which is ready for the
refinery and may be run into pigs in sand moulds as usual, or be other-
wise disposed of. The slag or undecomposed regulus or white metal
may be afterwards run into another set of moulds and sprinkled with
water, and that part worth resmelting may be picked out or separated for
the purpose. Pure pyrites may be smelted in the way herein-before
described with reference to regulus. Pure carbonates must be mixed
with sufficient mundic or other sulphur-giving material to fuse them
into a good regulus, but if either classes of ore are of very low per-
centage it will be better to smelt them in either reverberatory or blast
furnaces, separating the regulus, which must be collected and treated
separately.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Hunter Henry Murdoch in the Great Seal Patent
Office on the 23rd July 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HUNTER
HENRY MURDOCH, of No. 7, Staple Inn, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of January, in tho
year of our Lord One thousand eight hundred and sixty-nine, in the
thirty-second year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Hunter Henry Mur-
doch, Her special licence that I, the said Hunter Henry Murdoch,
my executors, administrators, and assigns, or such others as I, tho
said Hunter Henry Murdoch, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN THE SMELTING OF
COPPER, AND IN APPARATUS TO BE USED THEREIN," (a communication from
abroad by John Dixon, of Kapunda, South Australia,) upon the
condition (amongst others) that I, the said Hunter Henry Murdoch,
my executors. or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Hunter Henry Murdoch, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, that is to say :-
In reducing copper regulus by the pneumatic method great difficulty
has hitherto been experienced in applying the blast, the pipe or tuyere
for which being subjected to extremes of temperature is liable is fly to
pieces or become otherwise damaged.
Now the objects of this Invention are to remedy the above defect,

page_text: and under some circumstances to carry on the fusion of the ore con-
tinuously with the reduction of the regulus obtained thereby. These
objects are accomplished by means of a blast furnace of an improved
form, the said furnace being similar to an ordinary ironfounder's cupola
furnace, with the exception that a high-pressure blast is used and dis.
tributed in a zone or belt around the furnace just above the cupola part
by means of numerous air passages or tuyeres made through the lining
or side of the furnace at an anglo to the horizon, instead of a low-
pressure blast being introduced through one hole as in the ordinary
cupola furnace. The said tuyeres are supplied with air by means of
an air channel running round the exterior of the furnace and com-
municating with the said tuyere holes, into which channel air of the
required pressure is forced.
In smelting or reducing copper regulus according to this Invention
the said regulus is charged into the above-described furnace in the
manner herein-after described, and the melted regulus is allowed to
rise above the tuyeres, and is subjected to the action of the air
which is forced through the said tuyeres into and through the said
regulus.
Having thus described the nature of the Invention, I will proceed
to describe the manner in which the same is to be performed, referenco
being had to the Drawing hereunto annexed, and to the letters and
figures marked thereon.
Figure 1 is an elevation of a furnace constructed according to this
Invention, and Figure 2 is a vertical section of the said furnace taken
on the line W, Figure 4; Figure 3 is a plan of the said furnace, the
feeding stage of which is omitted in order that the relative positions of
the other parts may be the better shown; Figuro 4 is a horizontal section
of the said furnace, the said section being taken on the line X, Figure 2.
The other Figures represent details and modifications herein-after
referred to. The same letters of reference indicate the same parts in all
the Figures.
The furnace A, B, is made in two parts, the lower or cupola part A
heing capable of removal from the upper part B, as herein-after
explained. The sides a', 6', of the said furnace are made of fire-brick
surrounded by an iron casing a, b, between which and the said sides
spaces a, b, are left in order to allow for expansion, the said spaces
being filled with loam. The furnace is supported by pillars C, C, C,

page_text: This bulge is formed of slabs of
containing the tuyeres or air
the upper flanges of which are bolted to the flange of the air channel D,
the lower ends of the said pillars resting on the foundation wall E; Fis
the feeding platform on which the workman who feeds the furnace
stands, and G is a tunnel head by which he is protected from the fumes
of the said furnace, which said tunnel head has a feed hole g, through
which the said furnace is charged; a', a', are inclined air passages or
tuyeres situated in a zone or bolt around the furnace, through which
tuyeres air is forced into the melted regulus; a, a, are short metallic
tubes, which are fitted into the upper ends of the said tuyeres and have
flanges which are kept by the pressure of the loam close against the
inside of the casing, in which casing holes, the diameter of which is
rather larger than that of the said tuyeres, are formed opposite to and
communicating with each of the tubes a, a, so that should the parts
shift by expansion the full quantity of air will still be allowed to pass
without waste. A bulge is made in that part of the furnace through
which the tuyeres pass in order to resist or allow for the fluxing
action which is energetic at that part.
fire-brick or other suitable material
passages, the spaces between the said slabs being filled up with fan-
shaped bricks, as shown in Figure 4*, which is a horizontal section taken
on the line Z, Figure 2) of a segment of the furnace. About twenty
tuyeres three-quarters of an inch in diameter are sufficient for a furnace
three feet in diameter, in which furnace the regulus is allowed to rise a
foot above the lower ends of the said tuyeres. This height of charge is
indicated by the line Y, Figure 2. For a less depth of charge smaller
holes and a greater number of them should be used. The sides and
bottom of the casing 6 are held together by a ring of angle iron which
surrounds the lower part of the part B of the furnace. The part A is
secured to the said part B by means of screws aº, as, (one of which is
shown separately in plan, side elevation, and section in Figure 5) which
screws are screwed into the bottom plate of the casing 63, and have
shoulders which bear against a ring of angle iron a' affixed to the said
part A. This arrangement admits of the removal of the cupola part of
the furnace when it is wished to repair the same, all that is necessary
being to unscrew and remove the screws a, a, when the cupola part
can be lowered and removed by means of a travelling screw-jack or by
other suitable means. A little moist loam or fire-clay should be spread
on the upper surface of the brickwork of the part A before it is fitted to
the part B in order to prevent the passage of regulus between them.

page_text: The bed of the furnace is made of fire-clay, and is supported by a
plate a. is a tap-hole for the slag. As this tap-hole is required to
be opened to its fullest extent in the shortest possible time it should be
stopped with a ball of fire-clay with sand at the back of it, and then
the moveable plate 6° should be shut to, and secured by the bar b'.
ais a tap-hole at which the copper is run out; H is a pipo through
which the blast is forced into the air channel D by means of a suitablo
blowing engine; is a throttle valve which is worked with a crank by
any ordinary arrangement of levers, which crank is also connected with
the engine in any convenient way, so that the blast may be shut off
from or admitted to the furnace at the same time that the steam is shut
off from or admitted to the engine; I is a reservoir containing sand or
other flux, which is fed into the said reservoir through a funnel, fur-
nished with a stop-cock ; is a pipe through which the flux passes
to tho pipe H, whence the said flux is blown into the furnace, and
is a valve by which the communication through the said pipo is
opened or closed as required; is a pipe for equalizing the pressure
of air.
Figure 0 represents in vertical section a modification of the above-
described arrangement for regulating the supply of flux.
According to this modification the flux passes through an india-
rubber pipe J furnished with a pinch cock j, by which the sand is
admitted to an air-tight reservoir K supported by . The lower end of
the pipe J is affixed to the upper end of a short metal tube fixed in
the lid of the said reservoir, the lower end of which tube descends into
the said reservoir, as represented. From the said reservoir K the flux
passes through another india-rubber pipo L furnished with a pinch
cock to the blast pipe H. The furnace A, B, instead of being mounted
on pillars, as shown, may be built on the ground, in which case the
air channel herein-before referred to may be made semicircular in cross
section instead of triangular. The angle at which the tuyeres are repre-
sented as inclined is such that sufficient room is left for the tap-hole 6"
without dividing the air channel D, but if it is wished to have them
more horizontal the said channel must of course be divided, and closed
on each side of the said tap-hole.
When fan-shaped bricks are not easily obtainable rectangular bricks
may be used, as represented in Figures 7, 8, and 9 of the Drawing,
Figure 7 being a horizontal section of a segment of that part of the

page_text: furnace which contains the tuyeres, and Figure 8 a section showing the
courses of the bricks between and below the tuyeres, and also one of
the said tuyerés and part of the casing 6. Figure 9 represents plans of
the upper and under sides and a side elevation respectively of one of the
bricks in the course M', between which bricks the tuyeres pass. The
bricks M', M³, are fixed radially around the furnace, the spaces between
them being filled with fire-clay, through which thin metal tubes N
constituting the tuycres pass, their lower ends being fitted between semi-
circular grooves m (sec Figure 9) in the lower parts of the sides of the
bricks M'.
In smelting or reducing copper regulus according to this Invention
the furnace herein-before described is gradually heated with coke in the
usual way. A quantity of regulus containing as much copper as will
nearly fill the cupola part of the said furnace is then broken into small
pieces and charged into the said furnace. The blast is then gradually
turned on, and when the charge rises above the tuyeres moppa sand or
other silicious matter is blown in with the said blast from either of
the apparatus represented in Figures 1, 2, 3, and 6, in the proportion
of from one-half to three-fourths by weight of the said sand to from
one-half to one-fourth respectively of the iron which the said regulus
is found to contain. Or the said sand or other silicious matter instead
of being blown in with the blast may be kneaded up with tar or other
tenacious combustible into convenient balls or cakes, which are thrown
on to the coke in the furnace before the regulus, which is then piled
over the sand and coke as quickly as possible. Or the charge may be
divided into two or more equal parts, and the first part after being
thrown on may have a layer of coke thrown on after it, and then the
remaining part or parts of regulus may be thrown on so that a pile
may be formed of coke, sand, and regulus, coke, sand, and regulus,
and so on. This will allow the several portions of the charge to become
properly and quickly melted and prevent the chilling of the furnace.
The blast is gradually increased (as aforesaid) so as to melt the charge
as quickly as possible without blowing out the coke, the regulus being
allowed to rise over the ends of the tuyeres. As the lining of the furnace
unites more or less with the slag formed and tends to thicken it, and
as the success of the process depends greatly upon getting a fluid slag,
the usual means of reducing the quantity of sand or silica and adding
lime or other substance having the same property of thinning the slag
must be adopted. Immediately the air is blown through the charge

page_text: vivid and violent action begins and volumes of sulphurous gas i
are given
off. As soon as such action ceases the furnace is tapped. If it bo
furnished with two tap-holes, as shown in the Drawing, the slag is first
tapped from the tap-hole &, and the copper is afterwards tapped from
the tap-hole a. If however the furnace have but one tap-hole the
copper (which is ready for the refinery) is first tapped out and run into
pigs in sand moulds as usual, or otherwise disposed of. The slag or
undecomposed regulus or white metal is afterwards run into another
set of moulds and sprinkled with water, and that part worth resmelting
is picked out or separated for the purpose. The furnace is then charged
again and the operation described. is repeated. It is better to commence
tapping the slag before the, disengagement of sulphurous gas ceases.
If this be done too soon the only disadvantago will be that regulus or
"white metal" will run out from under the slag, but the said regulus
can be easily caught and returned to the furnace again. But if the
tapping be put off too long the slag will set in the furnace and render
it difficult to clear it for another charge. The blast should not bo
checked longer or oftener than is absolutely needed for fear of stopping
up the tuyeres and it should not be stopped until the charge has sunk
below the lower ends of the said tuyeres. A little steam may bo mixed
with the air when sulphurous acid gas is coming off, but the use of steam
is not claimed and is not essential to the process. There is a stage
during reduction at which the regulus has a tendency to "spurt." At
this stage the blast should not be checked unless the waste is excessive.
To blow through twelve inches in depth of regulus an engine capable of
maintaining a pressure of at least three pounds per square inch of surface
and (if twenty air passages or tuyeres three-quarters of an inch in
diameter are used) of discharging with that pressure through a hole of
nine square inches area must be used. Pure pyrites may bo smelted
in the way herein-before described with reference to regulus. Puro
carbonates must be mixed with sufficient mundic or other sulphur-giving
material to fuse them, but if either classes of ore are of very low per-
centage it, will be preferable to smelt them in cither reverberatory or
blast furnaces, and to separate the regulus, which must be collected and
treated separately:
Having thus described the nature of this Invention, and the manner
in which the same is to be performed, I wish it to be understood that
the said Invention is not limited to the precise details hercin-before
described, as they may be modified without departing from the naturo

page_text: of the said Invention; also that no claim is made to the smelting of
copper ores or regulus in a blast furnace (except as herein-after specified)
or to the use of sand or silica as a flux; but I claim as the Invention
communicated to me from abroad as aforesaid,-
Firstly. The improved construction of furnace or apparatus for smelting
or reducing copper herein-before described and illustrated in the accom-
panying Drawing, that is to say, a furnace having a zone or belt of
inclined radial air passages or tuyeres through which a high-pressure
blast of air is forced into and through the melted regulus contained
in the said furnace.
Secondly. The modification of the said furnace herein-before described
and illustrated in the accompanying Drawing, that is to say, making
the lower or cupola part of the said furnace capable of removal from the
upper part as and for the purpose described.
Thirdly. The process herein-before described of smelting copper ore or
regulus and reducing it to copper fit for the refinery continuously by
allowing the said regulus (in whatever way obtained) to rise above the air
passages or tuyeres in the furnace herein-before described and forcing a
high-pressure blast into and through the said regulus in contradistinction
to the ordinary process in which the ore or regulus on being melted
drops into the crucible and is not further acted on by the blast.
In witness whereof, I, the said Hunter Henry Murdoch, have
hereunto set my hand and seal, this Twenty-second day of July,
in the year of our Lord One thousand eight hundred and sixty-
nine
Witness,
B. WILLCOX,
his clerk.
H. H. MURDOCH. (L.S.)