IMPROVEMENTS IN KILNS, OVENS, OR FURNACES, IN CONTINUOUS FIRING, HEATED BY GAS OR BY SOLID FUEL FOR FIRING, BAKING, OR BURNING CERAMIC WARE, CEMENT, PLASTER, LIME, AND OTHER MANUFACTURES
Year: 1879

page_text: LETTERS PATENT to William Edward Gedge, of No. 11, Wellington Street,
Strand, London, in the County of Middlesex, Patent Agent, for the Invention
of "IMPROVEMENTS IN KILNS, OVENS, OR FURNACES, IN CONTINUOUS FIRING,
HEATED BY GAS OR BY SOLID FUEL FOR FIRING, BAKING, OR BURNING
CERAMIC WARE, CEMENT, PLASTER, LIME, AND OTHER MANUFACTURES." A
communication from abroad by Paul Marle, of Montceau-les-mines (Saône
et Loire). France. Engineer.
Sealed the 6th February 1880, and dated the 12th August 1879.
PROVISIONAL SPECIFICATION left by the said William Edward Gedge at
the Office of the Commissioners of Patents on the 12th August 1879.
WILLIAM EDWARD GEDGE, of No. 11, Wellington Street, Strand, London, in the
County of Middlesex, Patent Agent. "IMPROVEMENTS IN KILNS, OVENS, OR
FURNACES, IN CONTINUOUS FIRING, HEATED BY GAS OR BY SOLID FUEL FOR
FIRING, BAKING, OR BURNING CERAMIC WARE, CEMENT, PLASTER, LIME, AND OTHER
MANUFACTURES." A communication from abroad by Paul Marle, of Montceau-les-
Mines (Saône et Loire), France, Engineer.
This Invention relates to an improved furnace or kiln in constant firing, heated
by gas or by solid fuel for the purpose of baking or burning ceramic ware of all
kinds, cements, plasters, lime, and other products of manufacture.
It is constructed with the view of utilizing in the completest possible manner all
the heat disengaged from the fuel or combustible which is consumed therein, while
ensuring the regularity of the baking or burning.
As shown on the accompanying Sheet of Drawing forming part of this
Provisional Specification, this improved furnace or kiln is composed of a series
of compartments a¹, a³, a³, and so on to the number of from ten to twenty or more,
according to requirement, arrranged following each other in a circle or in two
parallel rows, as shown Figures 1 and 2 of the Drawing, the two rows being
separated by superposed galleries b, c, d, (Figures 2 and 3), and each of the com-
partments being separated from the next by means of two fixed partitions f and g
(Figures 1, 2, 3); these partitions however permit gases to pass from one
compartment to the other, the first one f by the top, the second one g by the
bottom; the gases also passing into the space left between these two partitions,
but this passage may be closed at pleasure by a damper or register h (Figure 1),'
placed between the two partitions or above that f. The furnace is also provided

page_text: with gas generators s (Figs. 1 and 2), running the whole length of the furnace,
and communicating at will with the compartments by means of the openings and
registers or dampers u (Figures 2 and 3), and flues x (Figures 2 and 3), which are
placed under the paving of the furnace, and distribute the gas in the entire breadth
of the compartment by means of small orifices pierced in the side of the flues
towards the combustion or fire grates v (Figures 1, 2, and 3).
Facing these flues & and on the other side of the grates are flues y (Figures 1, 2,
and 3), communicating at will with the galleries c or d by means of the registers or
dampers and m, and drawing from these galleries the hot air required for com-
bustion, which air escapes from the flues y by means of small orifices pierced at the
side, and facing those which bring the gas, so that the air and the gas mix and burn
all along the slit v which thus forms fire grate. If instead of burning gas it is
desired to burn solid fuel, coal, lignite, peat, wood, or other, the gas registers or
dampers u are closed, and upon the slits v are placed small gratings which are
charged with fuel by the openings P (Figures 1 and 3) formed in the roof or arch
of the furnace above each grating; the flues y always serve to supply air for
combustion. A chimney (Figures 1 and 2, carries off the products of com-
'bustion.
Besides the communications above set forth each compartment further
communicates,―
1°. With the outside by the openings q which serve for putting in and taking
out the ware or merchandise, and which are closed when it is desired to heat.
2°. With the gallery b and the chimney r by the orifices and registers or dampers
(Figures 1, 2, and 3) for the discharge of the products of combustion.
3°. With the gallery C by the orifices and registers n, which serve for the
introduction into this gallery of the air which has been heated in the compartments
filled with baked products in process of cooling; the air intended for cooling enters
the compartments either by the preceding compartments or by the flues y, and by
the vertical chimneys in which are placed the registers or dampers land m, or
lastly, by the openings for putting in the ware.
4°. With the gallery d by the same orifices and registers o which serve to
introduce into this gallery the air which has been heated in the compartments
filled with cooling baked ware or products; but whereas the gallery C receives air
from the hottest compartments, the gallery d receives that from the least hot.
I will now describe the working of the furnace :-
If I take a furnace with 12 compartments, like that shown on the Drawings, and
that it is doing its normal work, the compartment a' will be in process of filling or
putting the ware into the kiln.
The compartment a² will be in course of emptying or taking the ware out of the
kiln.
The compartments a³, a, a, a, will be cooling.
The compartment a will be in sharp fire.
The compartments as, as, a¹, will be in slow fire.
The compartments a¹¹, a¹², will be in course of drying.
The numbers placed following the letters indicate the number of the com-
partment to which the letter belongs.
The registers or dampers h and 10 being closed, and those 10 being opened, it is
into the compartment a' that fuel is charged or gas brought from the gas generator,
and where they are burnt. The air which is to quicken combustion enters first
into the compartment as by the Blues y³, and the vertical chimneys of the dampers
or registers and m; there it begins to heat, and then travels through the compart-
ments a, a, where it attains a high temperature in cooling the ware which has
just been baked; it then meets the register or damper h³, which bars its passage,
and compels it to pass into the gallery C by the orifices and registers or dampers n
which are open. From the gallery C it enters into the compartment a', where it is
drawn by the draught of the chimney through the registers or dampers 7 and the
flues
y, on issuing from which it meets the fuel or the gas from the generator, and

page_text: burns them, bringing the ware to be burnt or baked to the maximum temperature.
The gases arising from the combustion leave the compartment a7 by the opening
of the double partition ƒ and g which is not closed, and traverse successively from
bottom to top the compartments a³, a³, a¹0, heating the ware piled therein, and
cooling more and more finally escapes into the chimney by the registers or dampers
K10 which are open, and by the gallery b.
Thus the ware or products already baked and still warm serve to heat the air
employed for combustion, and the gases arising from this combustion serve to heat
the products which are to be baked later, so as to lose no portion of the caloric,
excepting that required for the draught of the chimney. Further, the hottest gases
always enter at the bottom of the compartments, which is the most difficult part to
heat, so as to have great regularity of temperature. It will be seen that the
compartment a6, the burning or baking in which is just completed, and which is at
its maximum temperature, is without any communication with the preceeding com-
partments, in order that the products at the high temperature at which they are
should not be attacked by currents of air relatively cold, which might cause them
to crack; they undergo in this compartment a rebaking, and a decrease of
temperature which secures them from ulterior accidents; it is one of the great
advantages of the gallery C that it permits the isolation of a compartiment without
interfering with the general working.
The register or dainper h placed in front of this compartment is subjected to a
very high temperature, but it should be observed that, placed between the partitions
f and g, it is very narrow; further, that it is supported in its entire length by two
projections from the partitions upon which it forms a joint by its weight, so as to
completely ensure the closing; and also that it may be made of.refractory materials
without presenting the least difficulty of working. The compartments all, a¹²,
are in the drying stage, that is to say, that by means of a current of hot air
the last traces of humidity are removed from the material, and its temperature
raised to prepare it for baking or burning; for this purpose the registers or
dampers ho and h¹² being closed, those k¹ open; the compartment all is placed
in communication with the gallery C by opening the registers 1; the vacuum
produced by the draught from the chimney draws the hot air into this gallery, it
penetrates under the grates of the compartment all, passes over the ware in drying
and heating it, and then into No. 12, where it produces the same effect, but in a
less degree, and finally escapes.into the chimney. Instead of taking hot air from
the gallery C, it may be taken from gallery d by the registers m, by putting this
gallery into communication with the compartment a², or even with the compart-
ment as if the heat given by a² is insufficient. This gallery d further serves to
carry to any point of the drying room or compartment placed above the furnaces,
the hot air which is permitted to escape therefrom by small openings left in the
roof or vault. When the compartiment a' has attained to the requisite degree of
baking or burning, the baking of compartiment as takes place, the various con-
dititions of all the other compartments thereby advancing one number by the
proper working of the various registers or dampers.
o
The lighting of the furnace is effected by means of one of the grates of the
gas generator transformed into an ordinary grate by means of a direct commu-
nication with the compartment a7. It is easy to pass from baking or burning
with solid fuel to baking or burning with gas, and after having baked one
compartment with solid fuel, the next one may be baked with gas, and so on
alternately.
This will be of great advantage to manufacturers having to bake or burn at one
time articles which need not fear contact with ashes, such as unglazed tiles and
slabs, at another time glazed articles ;.and also for those who have at one time fuel
suitable for making gas, but unsuitable for direct combustion, and at another time
a fuel excellent for direct combustion, which in this case is more economical than
that by transformation of the fuel into gas.

page_text: .
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said William Edward Gedge in the Great Seal Patent Office on the 10th
February 1880.
WILLIAM EDWARD GEDGE, of No. 11, Wellington Street, Strand, London, in the
County of Middlesex, Patent Agent. "IMPROVEMENTS IN KILNS, OVENS, OR
FURNACES, IN CONTINUOUS FIRING, HEATED BY GAS OR BY SOLID FUEL FOR
FIRING, BAKING, OR BURNING CERAMIC WARE, CEMENT, PLASTER, LIME, AND OTHER
MANUFACTURES.' A. communication from abroad by Paul Marle, of Montceau-les-
mines (Saône et Loire), France, Engineer.
"
This Invention relates to an improved furnace or kiln in constant firing, heated
by gas or by solid fuel, for the purpose of the baking or burning of ceramic ware of
all kinds, cements, plasters, lime, and other products of manufacture. It is con-
structed with the view of utilizing in the completest possible manner all the heat
disengaged from the fuel or combustible which is consumed therein, while ensuring
the regularity of the baking or burning.
On the accompanying Sheet of Drawing forming part of this Specification,-
Figure 1 shown in elevation and in longitudinal sections a furnace or kiln
embodying these improvements, Fig. 2 being a top plan and sectional view thereof;
and Fig. 3, a section at E, F, G, H, I, J, Fig. 2.
a¹ to a¹² indicate compartments of the kiln; b, smoke gallery or flue; c, gallery
or flue for superheated air; d, gallery or flue for hot air; f, g, partitions of com-
partments; h, registers or dampers of the compartments; K, registers or dampers of
the smoke flue; 7, n, registers or dampers of the gallery or flue for superheated air;
m, o, registers or dampers for hot air gallery or flue; r, chimney; s, gas generators,
also serving as grates for firing with solid fuel; t, gas flues or galleries; v, gratings
or fire bars for combustion of gas or the reception of solid fuel; x, galleries or flues
bringing the gas beneath the gratings or firebars; y, galleries or flues bringing bot
air under the fire grates; u, registers or dampers of the gas galleries or flues.
As shown, this improved furnace or kiln is composed of a series of compartments
a¹, a², a³, and so on to the number of from ten to twenty or more, according to
requirement, arranged following each other in a circle or in two parallel rows, as
shown Figs. 1 and 2 of the Drawing, the two rows being separated by superposed
galleries b, c, d, (Figs. 2 and 3), and each of the compartments being separated
from the next by means of two fixed partitions and g (Figs. 1, 2, 3); these
partitions however permit gases to pass from one compartiment to the other, the
first one by the top, the second one g by the bottom, the gases also passing into
the space left between these two partitions, but this passage may be closed
at pleasure by a damper or register h (Fig. 1), placed between the two partitions or
above that f. The furnace is also provided with gas generators s (Figs. 1 and 2),
running the whole length of the furnace, and communicating at will with the
compartments by means of the openings and registers or dampers u (Figs. 2 and 3),
and Blues (Figs. 2 and 3), which are placed under the paving of the furnace, and
distribute the gas in the entire breadth of the compartiment by means of small
orifices pierced in the side of the flues towards the combustion or fire-grates v
(Figs. 1, 2, and 3).
Facing these flues x, and on the other side of the grates, are flues y (Figs. 1, 2,
and 3), communicating at will with the galleries c or d by means of the registers or
dampers and m, and drawing from these galleries the hot air required for com-
bustion, which air escapes from the flues y by means of small orifices pierced at the
side, and facing those which bring the gas, so that the air and the gas mix and
burn all along the slit v, which thus forms fire-grate. If instead of burning gas it is
desired to burn solid fuel, coal, lignite, peat, wood, or other, the gas registers or
dampers u are closed, and upon the slits are placed small gratings, which are

page_text: ments, in order that the products at the high temperature at which they are should
not be attacked by currents of air relatively cold, which might cause them to crack;
they undergo in this compartment a rebaking and a decrease of temperature, which
secures them from ulterior accidents; it is one of the great advantages of the
gallery C that it permits the isolation of a compartment without interfering with
the general working.
The register or damper h³ placed in front of this compartment is subjected to a
very high temperature, but it should be observed that, placed between the
partitions and g, it is very narrow; further, that it is supported in its entire
length by two projections from the partitions upon which it forms a joint by its
weight, so as to completely ensure the closing; and also that it may be made of
refractory materials, without presenting the least difficulty of working.
The compartments a¹¹, a¹², are in the drying stage, that is to say, that by means
of a current of hot air the last traces of humidity are removed from the material,
and its temperature raised to prepare it for baking or burning; for this purpose the
registers or dampers h¹0 and h¹2 being closed, those K12 open; the compartment all is
is placed in communication with the gallery C by opening the registers 1, the
vacuum produced by the draught from the chimney draws the hot air into this
gallery, it penetrates under the grates of the compartment all, passes over the ware
in drying and heating it, and then into number 12, where it produces the same effect,
but in a less degree, and finally escapes into the chimney. Instead of taking hot
air from the gallery C, it may be taken from gallery d by the registers m, by
putting this gallery into communication with the compartment a², or even with the
compartment a³, if the heat given by a² is insufficient. This gallery & further
serves to carry to any point of the drying chamber, room, or compartment placed
above the furnaces, the hot air which is permitted to escape therefrom by small
openings left in the roof or vault. When the compartment a has attained to the
requisite degree of baking or burning, the baking of compartment as takes place,
the various conditions of all the other compartments thereby advancing one number
by the proper working of the various registers or dampers.
-
The lighting of the furnace is effected by means of one of the grates of the gas
generator, transformed into an ordinary grate by means of a direct communication
with the compartment a'. It is easy to pass from baking or burning with solid
fuel to baking or burning with gas, and after having baked one compartment with
solid fuel, the next one may be baked with gas, and so on alternately.
This will be of great advantage to manufacturers baving to bake or burn at one
time articles which need not fear contact with ashes, such as unglazed tiles and
slabs, at another time glazed articles; and also for those who have at one time fuel
suitable for making gas, but unsuitable for direct combustion, and at another time
a fuel excellent for direct combustion, which in this case is more economical than
that by transformation of the fuel into gas.
Having now described and ascertained the nature of the Invention communicated
to me as aforesaid, and in what manner the same is or may be performed,
I claim as secured to me by the herein before in part recited Letters Patent,-
The use of the general arrangement of this kiln, oven, or furnace, whether heated
by gas, or with solid fuel, or heated alternately in the one and the other way,
substantially as herein before described. Also, the arrangement of the parts thereof
differing from those previously adopted, and particularly,-
1°. The arrangement of the partitions ƒ and g which separate the compartments,
and permit giving to the gases a rational upward circulation from bottom to top,
whereas in kilns without partitions the gases always have a tendency to circulate
in proximity to the vault or roof, leaving the lower part of the kiln cold.
2°. The arrangement of the register or damper h placed between the two
partitions f and g, which permits the complete separation of the compartments from
each other at any temperature.
3°. The arrangement of the galleries or flues c and d of the registers or dampers_

page_text: l, m, n, o, which conjointly with the register h permit the transportation or
carrying of the heated air into any part of the oven or furnace of the kiln where
it may be required, or in any part of the drying chamber placed above it.
4°. The arrangement of the flues x and y bringing gas and air under the fire
grates, which arrangement permits the fractional division of the jets of air and of gas
to any desired extent, and the distribution or spreading of them at pleasure, so as
to obtain an equal heat over the entire breadth of the kiln, oven, or furnace, and in
all the joints of the compartment in firing.
In witness whereof, I, the said William Edward Gedge, have hereunto set
my hand and this Ninth day of February, in the year of our Lord One
thousand eight hundred and eighty.
W. E. GEDGE. (L.S.)