IMPROVEMENTS IN THE MANUFACTURE OF ZINC
Year: 1847

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALPHONSE
RENÉ LE MERE DE NORMANDY, of Bethnal Green, in the County of Middlesex,
Analytical Chemist, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-fourth day of
February, One thousand eight hundred and forty-seven, in the tenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Alphonsé René le Mere de Normandy, my exors, adñiors, and
assigns, Her especial licence, full power, sole privilege and authority, that I,
the said Alphonsé René le Mere de Normandy, my exors, adñiors, and
assigns, or such others as I, the said Alphonsé René le Mere de Normandy,
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 lawfully might make, use, exercise, and vend, within
England, Wales, and the 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 Alphonse René le Mere de Normandy,
shall cause a particular description of the nature of my said Invention, and
in what manner the same is to be performed, by an instrument in writing
under my hand and seal, to be inrolled in Her said Majesty's High Court
of Chancery within six calendar months next and immediately after tho

page_text: 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
Alphonsé René le Mere de Normandy, do hereby declare that the nature of
my said Invention, and 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 consists in certain Improvements in the Manufacture of
Zinc, and may be divided into two methods; the first applicable to the
reduction of the ores of that metal directly, that is, not in pots, crucibles, or
mouffles, but by a process similar to the smelting of iron ores in blast furnaces.
The second, by which is prevented the loss of zinc in the shape of white
oxide of zinc, which escapes in the atmosphere, pending the reducing or
smelting process of former methods, and which second method is also applied
in the manner herein-after described to the reduction of the zinc and oxides
of zinc which result from the treatment of the ore in the direct way, according
to the first method.
The following Figures will explain the manner of treating zinc ores or zinc
oxides according to the above-mentioned improvements.
Treatment of Zinc Ores in the direct way.-Figure 1 is a side elevation
of the smelting furnace. A is a hopper of cast iron surrounded by bricks,
for the purpose of preventing the radiation of the heat, so as to render the
charging more commodious to the workman. This hopper may of course be
made altogether of bricks or of slabs provided they be well jointed. B is a
valve or trap door, for the purpose of holding the charge, as will be explained
further on. C is the interior of the furnace. D are the inner walls of the
furnace, built with the best refractory bricks that can be obtained. E are
the external walls of the furnace, which may be built of refractory bricks of a
less costly nature. F is a lining of fire clay, for the purpose of effectually
rendering the furnace tight, and preventing the escape of the volatilized zinc.
This joint is made by leaving a space of a few inches between the inner and
outer walls of the furnace, which the mason fills with loose somewhat damp
refractory or fire clay, and rams strongly between as he proceeds with the
building. G is the neck of the furnace, which, as may be seen in the
Drawing, has some resemblance to a retort, and it is through this neck that
the products of combustion and the volatilized zinc first pass, and thence into
the tube I, which will be described presently. H are holes in the masonry,
for the purpose of clearing the necks G and M, in case they should become

page_text: choked. I is a tube, which I prefer made of wrought iron rivetted, and one end
of which is fastened, bolted, or supported in any convenient, secure, and tight
manner to the descending portion of the neck or bend G, whilst the other
extremity of the said tube plunges several inches into the water tank P.
This tube I is jacketed, that is to say, it is concentric to another tube J, the
lower extremity of which is water-tight. In fact, it is a tube within another
tube, rivetted at bottom, and water is made to circulate in the space between
the inner and the outer tube, so as to keep the tubes comparatively cold.
J, second tube, of which I have just been speaking. K is a pipe connected
with the outer tube J, for the purpose of admitting water in the space
between the two tubes, and the water falling from a higher level than the
orifice of the outer tube J, constantly displaces the heated water, which runs
over or may be led away. L and L' are water pipes, the object of which is
to supply the pipes K and N, and therefore the tube I and J with the necessary
water. M is another neck of the furnace, exactly similar to G, and having
like the latter two concentric iron tubes, exactly similar to I and J, but which
cannot be scen in this Figure. It is not necessary to the success of the
process that there should be more than one neck, but I have found it advan-
tageous in practice to uso more than onc, as it divides the current of the
products of the combustion, and causes them to enter the condensing appa-
ratus in greater volume and with less violence, so as to be in a better state for
condensation. It will be observed that in the Figure the necks are at different
levels. That is not necessary to the success of the process, but I have used two
necks at different levels with good effect. N is a pipe absolutely similar to the
pipe K, for the purpose of adnitting water between the iron tubes of the second
neck M. O, water twyers, in order to admit the blast into the furnace. Tho
blast may be either cold or hot, but I prefer the hot blast, on account of
the economy of fuel; and I consider best to lute these twyers well, so as to
prevent all regurgitation of blast. P is a close water tank, filled with water
up to P', and in which the tubes I of the neck G and T of the neck M plunge
several inches. P' is a partition or wall fastened to the cover of the tank, and
plunging a fow inches in the water of the tank P, and under which the gases
and products of combustion are compelled to pass for the purpose of condensing
the oxide produced. This partition I have found highly useful, but a partial
success may be obtained without it. Q is a tube which leads the products of
combustion and the oxide of zinc which has escaped condensation into the
tank R. R is a second tank, filled with water up to R', and into which the
oxide of zinc which has escaped condensation in the first tank is retained. R' is
a partition or wall similar to P¹. S is a tube through which all that which

page_text: has not been condensed escapes. Figure 2 is a side elevation of the same
furnace, representing the other side, in order to shew the shorter neck M and
the tubes T and U, in every respect similar to neck G and to tubes I and J.
V is the ash or cinder hole. X is a third twyer. The other letters correspond
to those of Figure 1. Figure 3 is a front view of the same furnace, and a
vertical section of the descending or condensing tubes. The letters correspond
to those of the other Figures. Figure 4 is a plan of the furnace, with an
external view of the tanks. The horizontal section of the furnace is level
with the twyers. P' and R' are the screws which hold the partition, marked
with the same letters in the other Figures. The other letters are corre-
sponding to those of the other Figures.
Figure 5 is the same Figure as Figure 1, with this only difference that the
products of combustion first enter an empty box X, X, surrounded with
water W, for the purpose of condensing, in the dry way, a more or less
considerable portion of oxide of zinc or of metallic zinc. This tank may be
used without being surrounded by water, but I prefer using it with the water,
because the tank is thus maintained at a lower temperature. The portions
which have not condensed in that tank pass then over the partition or wall Y,
through the tube Z, and thence into the tanks P and R full of water, as I
have explained it in the other Figures.
Figure 6 is a plan of the Figure 5, shewing the interior of the tanks.
I and T are the descending or condensing tubes; Y the partition of the empty
tank X, X; W is the water bath by which this empty tank X, X, is sur-
rounded; Z is the tube which leads the uncondensed portions into the tank P,
and so forth for the other letters. The partitions of the tanks P and R,
marked P¹ and R' in the other Figures, do not appear here, because they are
fixed to the cover of these tanks.
Having thus described the apparatus, I will now indicate how I use it.
The first thing to be done is to open the door or trap B, and to introduce the
up, which
fuel gradually, augmenting the quantity of the fuel until the heat is
will require perhaps two or three days, the blast being regulated, which is well
understood by all men accustomed to furnace work, and need not be further
described. The heat being at the proper point, that is to say, at a white
heat, and the furnace all ready, the blast is momentarily turned off, and the
charge being thrown in the hopper A the door or trap B is opened, by which
means the charge of course instantly descends into the furnace, and the trap
is immediately shut down, so as to leave the furnace open as short a time as
possible. The charge consists generally of equal parts of ore (which should be
prepared in the usual way) and of coke. These proportions may, however,

page_text: be modified according to the nature and quality of the ore. This being done,
the blast is again returned to the furnace, the mass sinks gradually as the coke
is burning, and the ore is reduced, the metal is volatilized, and then with the
products of combustion escapes through the necks G and M, through the
pipes I and T, in which the condensation begins, and the condensed portions
are deposited in the water of the first tank P and of the tank R. That which
is found condensed in these tanks is chiefly grey oxide of zinc, mixed with
metallic zinc, whilst the oxide of carbon, carbonic acid, and other uncondensed
products, escape by or through the tube S, owing to the pressure of tho
blast. Or, if the modifications represented in Figures 5 and 6 be resorted to,
a portion of oxide is also found in the dry tank X, X.
I consider that two pounds and a half to the inch pressure of blast is
sufficient, but I do not confine myself to that pressure, as it may be found
advisable to augment or diminish it. I can only say that about two pounds
and a half pressure to the inch has answered the purpose. It is evident that
the quantity or number of the tanks may be augmented further, but then the
pressure of blast must be modified accordingly. When the operation is once
begun it may be carried on night and day, like an ordinary iron smelting
furnace, the workmen putting fresh charges from time to time through the
hopper, as before described, collecting from time to time the mixture of grey
oxide of zinc and of metal which has deposited at the bottom of the tanks;
whilst this is doing the blast is turned off, and the water of the tank will run
off into any other convenient receptacle by opening a sluice, which is not
represented in the Figures, but which may be placed at any convenient part
of the tank, and the deposit at the bottom is raked off and kept for further
treatment, as will be stated hereafter. The tanks from which the water has
been run off are to be refilled with water. If a dry tank × × is employed, the
oxyde therein may be collected at the same time. The blast is now turned
on again, and the operation is resumed as before. The water which has run
from the tank into a suitable receptacle (which may be another tank on a
lower level) being left at rest will deposit another portion of grey oxyde, which
it held in suspension, and from which it may be decanted, and the deposited
oxyde being collected is added to that which was raked from the tank, as
before mentioned. The mixture of grey oxyde and of metallic zinc are now
mixed with about one fifth of their weight of coke or coals, and treated in
crucibles, pots, or mouffles, in the usual way of smelting zinc, with the second
improvement presently to be mentioned, by which means it will be reduced to
the metallic state in grains or in lumps, which being remelted per se are
finally cast into ingots, as is well known to zinc smelters.

page_text: My second improvement refers to the usual mode of treating zinc orcs and
zinc oxydes or compounds, and consequently also the mixture of grey oxyde
and metallic zinc obtained by the direct treatment of zinc ores in the smelting
or blast furnace above described.
Figure 7 is a side elevation of a Silezian oven for the treatment of zinc ores.
The Silezian oven is given as an example, but the Invention is applicable to
the Belgian and other usual modes of making zinc, where there is a waste of
zinc in the way which my Invention obviates, as presently to be stated. A is
the furnace, B the grate, C the clay mouffle or crucible, containing the charge
C. D, the clay pipe called "boot" through which the reduced zinc volatilizes.
E, the pipe in which the zinc fumes are condensed. All these things are
well known, but the remainder constitutes my improvement, which is intended
to prevent the loss of that portion of zinc which having escaped condensation
evaporates or burns in the air, and is irretrievably lost. In effect in the
sketch Figure 7, the lower orifice of the condensing pipe E in the systems
above alluded to being exposed to the air, a portion of zinc which has not had
time to condense in the metallic state, or which was too minutely divided to
do so, catches fire as soon as it reaches the air, and burning away or evaporating
at the orifice of the pipe is lost. It is this defect which I have successfully
endeavoured to remedy, which is done as follows:-F is a box containing small
pieces of coke, through which the condensing pipe passes, and the bottom of
which is furnished with cross bars sufficiently close to retain the beforesaid
pieces of coke. The coke or other substance in this box may be damped
with water, as occasion requires; such damping is useful to prevent the coke
or other combustible matter from catching fire, and I consider that it also
tends to assist condensation. G is another box placed under the coke box F,
which it fits, and which box is filled with water as far as H, and kept so
filled, so that only the space of about one inch is left between the upper
box F and the level of the water in box G. I is a small pipe, serving to
keep the water in the box at the proper level. K is an arch for the con-
venience of being able to move round the boxes. The object of the apparatus
is as follows:-The zinc reduced as usual condenses in the condensing pipe E
and falls in the water of the box G, into which is also deposited the largest
portion of the finely divided zinc, which otherwise would burn away and be
wasted, whilst the small portion which even then escapes condensation is
retained amongst the coke in the coke box. Coal or charcoal might be used
instead of coke, but I consider the coke to be preferable. Bundles of wire,
layers of metallic cloth or gauze, small pieces of brick and other such
substances capable of standing the process, and arranged so as to prevent the

page_text: burning of the fumes of zinc and waste thereof, by presenting as an obstacle
a series of small interstices, and at the same time permitting the escape of tho
uncondensed products, would answer the samo purpose, but I prefer coke or
other such substance, which I may at onco put into the mouffle, mixed with
an ordinary charge of ore, or with the grey oxyde and finely divided zinc
obtained by the process first described. If substances which cannot be so
treated are used in the box, the oxyde of zinc must be separated from them by
washing, and then recharged in the mouffle as above.
Having now described my said improvements, I do not claim as my Inven-
tion the putting of the ores of zinc along with coke in a smelting furnace,
nor the applying of cold blast to the smelting of such ores. But I do claim
as my Invention the condensation of the oxyde of zinc and of the metallic
zinc volatilized, by causing the products of combustion (which they are mixed
with) to pass from the blast furnace through closed tanks of a convenient size,
and provided with partitions, or even without, though in that case, as I have
already said, the result is not so beneficial, some of which tanks may be
empty or filled with water, as I have already described, or of any other
form acting in the same manner, that is to say, by compelling the products
of combustion after having traversed the water of the tanks to repass through
water by the pressure caused by the accumulation of the gases at the
upper part of these tanks, which tanks may all be filled with water, or else
be some of them full, the other empty alternately with each other, in what-
ever order.
And I claim that mode of condensation, whether used in combination
with the hot blast, which I have found may be advantageously employed, or
not in combination therewith.
And also I claim as my Invention the use of a box filled with pieces of
cokc, coal, or charcoal, or of brick or other materials capable of acting
in the manner already described, placed over another box filled with water,
as also already described, the use of which box of water and alone, I do not
claim.
And I claim each of the said Inventions so claimed whether used separately
or conjointly.
•
In witness whereof, I the said Alphonse René le Mere de Normandy,
have hereunto set my hand and seal, this Twenty-fourth day of
August, in the year of our Lord One thousand eight hundred and
forty-seven.
ALPHONSE (L.s.) LE MERE DE NORMANDY.

page_text: AND BE IT REMEMBERED, that on the Twenty-fourth day of August, in
the year of our Lord 1847, the aforesaid Alphonse René le Mere de
Normandy, Esq, 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.