IMPROVEMENTS IN THE MANUFACTURE OF ZINC
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, NICHOLAS
TROUGHTON, of Swansea, in the County of Glamorgan, Gentleman, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-second day of May, in the second year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, tho
said Nicholas Troughton, Her especial licence, full power, sole privilege and
authority, that I, the said Nicholas Troughton, my exors, admors, and assigns,
or such others as I, the said Nicholas Troughton, my exors, adñiors, or
assigns, should at any time agree with, and no others, from time to time
and at all times during the term of years therein expressed, should and law-
fully might make, use, exercise, and vend, within England, Wales, and tho
Town of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF ZINC ;" in which said Letters Patent is contained a proviso
that I, the said Nicholas Troughton, shall cause a particular description of
the nature of my said Invention, and in what manner the same is to be per-
formed, to be inrolled in Her said Majesty's High Court of Chancery within
six calendar months next and immediately after the date of the said in part
recited Letters Patent, as in and by the same, reference being thereunto had,
will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Nicholas Troughton, do hereby declare the nature of my said Invention, and

page_text: the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, reference being had
to the Drawings hereunto annexed, and to the figures and letters marked
thereon (that is to say):
My Invention relates to the application of certain arrangements of appa-
ratus in the process of calcining or roasting zinc ore; and, secondly, to the
application of certain improved apparatus in the process of smelting zinc ore.
And in order to give the best information in my power, I will procced to
explain the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 represents the section of a series of retorts arranged and con-
structed according to my Invention for calcining zinc ores; and Figure 2 is
a section on a large scale of part of a retort by which the manner of putting
together of the parts will be more readily understood. I would here remark
that my Invention is an improved construction of retorts for roasting or
calcining zinc ores where such calcining is performed by external heat in
place of calcining in reverberatory furnaces, wherein the heat and flame from
the fuel comes directly in contact with the matters under operation. At the
same time I would remark that I am aware that it is not new to roast or
calcine zinc ore by means of retorts or such like vessels externally heated, but
the using of retorts for such purposes, as heretofore practised, has been by
means of retorts moulded of the size required in one piece or in one complete
vessel, and although such description of retorts are found more advantageous
than the reverberatory furnaces for such processes, yet the difficulty and con-
sequent cost of making sufficiently large vessels or retorts of clay in one piece
is an objection to their being brought generally into use. Now, the object of
this first part of my Invention is to construct the retorts of several pieces, by
which not only is much expence saved, but larger retorts may be constructed
with ease; and I prefer that such retorts should be formed of a series of fire
tiles, each being a parallelogram, but this is not essential, but I believe will be
found the best construction both in respect to first cost and after repairs, and
such retorts will be found to offer less substance of matter to be kept heated
in acting on a given quantity of ore than when separated and distinct retorts,
each moulded and formed into one vessel, are used; at the same time retorts
may be advantageously made by moulding a series of parts of retorts, as at
Figure 3, which being joined end to end with fire clay will make excellent
retorts, but at a cost greater than those herein explained both as to their
structure and setting to be acted on by the heat from proper furnaces or fire-

page_text: places. The retorts, shewn at Figures 1 and 2, composed of a series of fire
tiles or slabs a, a, a, are the slabs or tiles which constitute the bottoms of
the retorts; b, b, are the tiles or slabs which constitute the upper surfaces or
tops of the retorts; and c, c, are the slabs or tiles which are placed vertically,
and produce the sides of the retorts. The back ends of the retorts are closed
by similar tiles or slabs, each having a hole through for the passage of the
vapours evolved from the ores, such vapours being received and conveyed in
any direction by the flue at that end, and being thus separated from the
products of combustion may be separately acted on according to either of my
former Patents, when treating of the separated vapours of copper ores in
the process of calcining or roasting such ores, or the separated products of the
ore may be allowed to pass into the atmosphere; and it will be found that by
the mode of treating zinc ores in furnaces or retorts, such as are above
described, considerable saving of fuel will result, and the zinc ore may be
more evenly roasted or calcined. The front ends of the retorts are closed by
means of tiles or doors having a small hole or opening in each for the passage
of atmospheric air, and the holes may be closed or more or less open according
to the object required. The retorts are charged through the stoppers above,
which have proper slides to close the openings into the retorts, the quantity
charged into each retort being sufficient to cover the lower surface thereof
to two or three inches deep, and the ore is to be raked from time to time to
change the surfaces, and the retorts are kept to a moderate red heat.
I will now proceed to describe the second part of my Invention, which
relates to another arrangement of apparatus or furnace for calcining zinc ores,
but in this instance the ore is subjected to the direct action of the products of
combustion, and the zinc ore is so acted on that one portion is being treated
in the calcining furnace in a similar manner to the ordinary working of such
furnaces, at the same time the furnaces are so arranged that other zinc ore is
going through a preparatory process of the heat which has passed away from
the ore which is undergoing the completing process of calcining.
Figure 4 represents an elevation in section of a furnace constructed
according to my Invention, and Figure 5 is a plan of the same in section..
And I would remark that this furnace for calcining zinc ores may be heated
by a separate fire, to burn by blast or by draft, or the flue from the smelting
furnace may be conducted into the entrance of this furnace, and the otherwise
waste heat of the smelting furnace thus brought into useful application for
calcining or roasting of zinc ore. And this part of the Invention is applicable,
whether it be applied to the furnace or to the retorts herein-before explained,
and will be found a means of saving much fuel in the processes of obtaining

page_text: zinc from ore. In Figures 4 and 5, a represents the furnace, which is shown
suitable for blast; and a constant supply of fuel is kept up in the chamber b,
there being a close cover with a sound joint; c is the bed or floor, on which the
ore is spread in like manner to an ordinary reverberatory furnace, and is
stirred about on that floor by passing the ordinary rakes or instruments through
the openings d, d, and when the process has been sufficiently carried on the
ore is discharged through the openings e, e, these openings at other times
remaining closed by fire tiles slided over them. The heat of the fire and
the flame thereof passing in contact with the ore on the floor or bed c also
acts on the roof f, and that roof f being hot reverberates the heat on to the
floor or bed, at the same time the heat which passes through the roof heats
the ore in the upper chamber g; and in addition to such heat passing through
the roof, the flame and heat from the furnace having passed over the zinc ore
in the lower compartment of the apparatus enters into and passes over the
ore in the chamber g, and in doing so heats the roof h of the chamber g, and
also the ore in the chamber g; and it will be seen that there is a third
chamber ; the heat, therefore, which passes through the roof h heats the ore
in the chamber i. In working this arrangement of calcining furnace or
apparatus, when the charge is withdrawn from the lower chamber, the charge
in the chamberg is to be raked into the lower chamber through the openings
for that purpose, which at other times are kept covered with fire tiles, as
shewn in the Drawing, and the charge in the chamber i is to be raked into
the chamber g, and a fresh supply of ore charged into the chamber i.
I will now proceed to describe the third part of my Invention, which relates
to a mode of arranging a series of retorts side by side, and of applying heat
thereto in the process of smelting or distilling zinc from the ore. According
to the practice most generally pursued in smelting zinc, the ore is submitted
to the action of heat in crucibles, having descending iron pipes, which enter
into vessels containing water, all which is well understood, as well as the
process of smelting or distilling zinc from the ores. And I mention these
matters now, in order to state that so far as the process of operation is
concerned, my Invention does not differ from that in treating the ore in
crucibles, but only in the construction and arrangement of apparatus and
means of applying heat thereto.
Figure 6 is a side elevation of two sets of furnaces and retorts, arranged
according to my Invention, one of the furnaces being in section; Figure 7
is a plan in section, and Figure 8 is a transverse section. a, a, are a series
of retorts of fire-clay, arranged side by side on a shelf of slabs or fire tiles.
These retorts are each closed at one end and open at the other, such open

page_text: end being capable of being closed, when in operation, by a tile or door b,
fitting closely and luted with fire-clay, as will readily be traced in the
Drawing. Each set of series of retorts so set side by side is placed in a
chamber c, c, in such manner that the heat and flame of the fire will pass
from the fire-place or furnace, and act on one side of the retorts, and having
passed along all the series will pass to the upper part of the chamber c, c,
and pass along and heat the other side of the retorts, and as the fires are
maintained and urged by means of blasts of atmospheric air, and there are
dampers placed at the commencement of the flues to the chimneys, the heat
may be maintained and regulated with great advantage and at comparatively
small cost. The blasts of air may be produced by any ordinary blowing
machinery. I prefer the rotatory blowers now in extensive use, and well under-
stood, and the air may be cold or heated; and in case I employ anthracite
coal as the fuel, I use hot blast, heating the air to at least five hundred
degrees of Fahrenheit, and such heating is to be performed by any of the well-
known means now very generally resorted to for heating the blasts of air for
smelting iron, and which being well understood do not require any description
in this my Specification. d, d, are iron pipes descending from the retorts, and
entering into vessels containing water, similar to the apparatus at present in
use for like purposes. It will be seen that the Drawing shows four chambers c,
each heated by its separate furnace or fire-place; such fire-places having
openings to be closed when at work. And in order to keep up a supply of
fuel to the fire, each furnace or fire-place has an inclined chamber e, which is
filled with fuel, and then closed air-tight by the cover f, fitting into a sand
bath or joint, in order to prevent draft upwards, by which means only the
lower portion of the fuel will be in an ignited state when at work; g, g, are
a series of iron doors, one opposite the mouth of each retort. These doors
are capable of being removed by sliding them upwards till the portions cut
out at the sides come opposite the dips or holders h, h, when the doors may
be removed in order to get at the retorts. The arrangement of the brickwork,
the construction of the furnaces, and the setting of the furnaces being clearly
shown in the Drawing, no further description need be given.
I would remark that I am aware that it has been before attempted to
employ retorts in the smelting of zinc. I do not, therefore, claim the same
generally; but I do claim, in respect to this third part of my Invention, the
mode of placing a series of retorts in a chamber c, and causing the heat and
flame to pass along under and over such series of retorts, as above described.
And I do also claim the mode of smelting zinc by means of blast, whether
the heat of the fuel is caused to act on a series of retorts or vessels in the

page_text: manner shewn, or on other arrangements of retorts or vessels placed in a
suitable chamber or chambers.
In witness whereof, I, the said Nicholas Troughton, have hereunto set
my hand and seal, this Twenty-second day of November, in the year
.D.)
AND BE IT REMEMBERED, that on the Twenty-second day of November,
in the year of our Lord 1889, the aforesaid Nicholas Troughton came before
our said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Twenty-second day of November, in the year of our Lord
One thousand eight hundred and thirty-nine.