IMPROVEMENTS IN AND ADDITIONS TO KILNS FOR BURNING OR BAKING CEMENTS, GYPSUM, LIMES, BRICKS, TILES, POTTERY, AND OTHER SIMILAR SUBSTANCES
Year: 1881

page_text: LETTERS PATENT to Edgar Edmonds, of the Firm of Robertson, Brooman, and
Company, of 166, Fleet Street, in the City of London; Patent Agents, for an
Invention of "IMPROVEMENTS IN AND ADDITIONS TO KILNS FOR BURNING
OR BAKING CEMENTS, GYPSUM, LIMES, BRICKS, TILES, POTTERY, AND OTHER
SIMILAR SUBSTANCES." A communication from abroad by Charles Amand,
Engineer, of 22, Rue du Chateau, Tournay, Belgium.
PROVISIONAL SPECIFICATION left by the said Edgar Edmonds at the Office
of the Commissioners of Patents on the 5th February 1881.
"
EDGAR EDMONDS, of the Firm of Robertson, Brooman, and Company, of
166, Fleet Street, in the City of London, Patent Agents. IMPROVEMENTS IN
AND ADDITIONS TO KILNS FOR BURNING OR BAKING CEMENTS, GYPSUM, LIMES,
BRICKS, TILES, POTTERY, AND OTHER SIMILAR SUBSTANCES." (A communication
from abroad by Charles Amand, Engineer, of 22, Rue du Chateau, Tournay,
Belgium.)
The improved kiln which forms the object of the present application for Patent
is composed of two principal parts or elements, viz., the kiln proper and the
gazogene."
**
-
+
The Kiln. The kiln is composed of a gallery or bricked chamber, say, 15.05
metres long by 304 metres interior width, or of such other length as may be
required, according to the class of matter to be burnt or calcined. This gallery or
chamber is constructed on walls of masonry arranged in such manner as to permit
the circulation of atmospheric air under the sole or bottom of the kiln, and thus
maintain a low temperature at the metallic parts of the waggons or trucks.
The gallery or chamber contains, say, 5 waggons or trucks, each 3 metres in
length, and their bottoms or platforms, which are made of refractory bricks or
blocks, form the sole or bottom of the kiln.
Any other number of trucks may be of course employed, according to the material
being baked or calcined. .
The waggons or trucks run on iron rails 1.50 metres apart or gauge from axis to

page_text: axis, the said rails resting on longitudinal sleepers of oak, which are embedded in
and supported by walls of masonry.
The waggons or trucks are fitted with sides of refractory material 0.20 metres
wide at the base and 0.10 metres wide at the top, and rest on the platform (or sole
of the kiln), and rise up to the spring of the gallery arch.
These refractory sides, which prevent the products from falling against the walls
of the gallery or chamber, especially in the case of cement or of line, are pierced
with holes or apertures through which the flames pass and penetrate into the mass
of the products to be burnt, and leave by the opposite side of the waggon after
having followed a course or direction normal to the longitudinal line of the kiln.
Two sliding doors fitted with equilibrium counterweights, which enable the
rapid execution of the ascending and descending movements for opening and
closing, are placed one at the entrance and the other at the exit from the gallery
or chamber.
«
Perfect closing is effected by rapidly luting with clay.
At the middle of the length of and under the gallery are arranged four
recuperators" of heat, placed two by two at each side.
Each group of two comprises one "recuperator" for air and one for gas. Above
each of them are arranged twelve flues, which terminate in mouths or apertures
placed on the same level as the upper surface of the sole.
When the hot air and the heated gas leave these mouths or orifices they ignite,
and the flames after having passed through the products to be burnt are sucked or
drawn into the mouths or orifices of the opposite group of " recuperators," passing
through them from top to bottom and heating them, and from thence they pass to
the draught chimney after passing the distribution doors and the horizontal chimney
placed in front of the " recuperators."
Each group of two "recuperators" is at one time an emission group, and at
another time an exit or draught group, and to effect this change in the action all
that is required is to work the distribution doors of the air and gas which are
placed in front of the "recuperators" in the distribution chamber.
Along the longitudinal walls of the gallery are imbedded two sheet iron trenches
containing sand, into which dip or plunge the sheet iron plates carried on each side
of the waggons under the sole. These sand trenches and iron plates thus form a
longitudinal joint on each side and along the whole length of the gallery, preventing
any penetration of the atmospheric air into the gallery above the sole of the
kiln.
In front of and along the whole width of each waggon is an iron bar fixed to
the iron frame of the waggon; this penetrates into two other iron bars arranged
in the same way at the back part of the preceding waggon, clay being placed
between them.
A hermetic joint is thus established between each waggon.
It will thus be seen that longitudinally and transversely between each waggon,
likewise at the entry and exit to the gallery or chamber, there is perfect and
complete isolation of the upper part of the gallery or chamber above the sole,
which is hot from the under part which is in communication with the atmosphere.
A winch is placed at the exit or outlet from the kiln, and is so arranged that ten
revolutions of the crank will cause a forward movement of exactly three metres, or
the length of one waggon, to be imparted to the five waggons inside the kiln.
The railway under the kiln on which the waggons run has an incline of 0.007
metre per metre from the entrance to the outlet or exit.
This incline has been so calculated as to equilibriate the resistances of friction
and of the inertia of the train of five waggons.
"
Should the length of the kiln be increased or diminished, and consequently the
number of waggons be altered, then this incline must be modified accordingly.
The "Gazogene."-The " gazogene which is employed in connection with the
present Invention is that known as the "Siemens" system; it is placed at the side
and at the back of the kiln. The gases are conducted to the distribution doors by

page_text: an iron pipe. It has been observed from what has been described above how these
gases, combined with air, arrive at the mouths or apertures, where they ignite,
after having previously and in a separate state passed through one or other of the
recuperator" groups.
cement:-
After the kiln has been well dried, four empty waggons and a fifth carrying the
products to be burnt, about 16,000 kilogrammes, are successively introduced through
the entrance door, the luting is effected, and the heating is commenced, which is
gradually augmented.
When it is known that the first charge is sufficiently dry the doors are opened,
and an empty waggon is withdrawn at the outlet, and at the same time that a
fresh load of products is introduced at the other end.
The heating is then brought up to its full force, and when the products pre-
viously dried are judged to be sufficiently calcined the foregoing manoeuvre is
repeated, which brings the first charge or load in front of the flame apertures or
mouths.
At this moment the products carried by the waggon in front of the flame
apertures or mouths are calcined and about to be burnt, the products carried by
the waggon immediately behind are dried and about to be calcined, and finally
the products just introduced are still wet and are about to be dried.
To effect these operations the distribution doors are opened further so as to
augment the flames which burn the products placed on the waggon in front of the
flame apertures or mouths, the flames penetrating the products transversely, and
imparting to them a large part of their heat.
After leaving this mass of products the flames are drawn into the opposite group
of "recuperators" in direct communication with the draught chimney.
After a certain lapse of time the products placed on the waggon in front of the
flame apertures or mouths are completely burnt, and a fresh charge or load is
introduced, which forces the charge beyond the flames, where it gradually cools
until the time it is withdrawn.
It will be seen that this movement of waggons is most simple.
In consequence of the arrangement of this kiln, and of the manner in which the
mass to be burnt is to be distributed, the flames completely embrace the latter, and
the exact temperature required for burning Portland cement is thus obtained.
This temperature is ascertained by a pyrometer, and maintained by opening the
distribution doors more or less.
The mass to be burnt is thus exposed to a temperature of from 400 to 500
degrees for drying; for calcining it is exposed to a bright red heat, and finally it is
exposed in front of the flame apertures or mouths at a white heat, where it is
burnt.
When products other than cement are to be burned the exact degree of tempera-
ture suitable for them is obtained by opening the distribution doors more or less,
and in like manner they may be submitted to the direct action of the flames more
or less slowly, and be allowed to cool more or less rapidly after the burning by
lengthening or shortening the gallery of the kiln, which in all cases contains as
many waggons as there are number of times three metres in its length.
For burning bricks the long and costly operation of preparatory drying may be
dispensed with by constructing a very long gallery, and thus their manufacture
may be carried on in winter equally well as in summer, and in any weather.
In this case and to facilitate this progressive drying in the kiln previous to burning
instead of allowing the hot gases to proceed to the chimney after leaving the
draught or suction set of " recuperators," they are caused to return into the kiln at

page_text: the entrance end by means of a flue penetrating into the kiln at about eight metres
from the last flame apertures or mouths.
The gases thus pass through and dry the last products introduced, and from
thence pass to the chimney through a flue formed in the arch of the kiln near the
entrance.
It is sometimes desirable in the case of certain products, such as bricks, that two
waggons should be submitted to the direct action of the flames at the same time;
the flame apertures or mouths are then extended to twice their ordinary length,
that is to say, to 6 metres long.
In addition to the important advantages of a continuous burning, of imparting
the exact temperature necessary for the burning of various kinds of products, and
of progressively bringing the products up to the temperature for burning, as also
in cooling them progressively according to their nature; in addition to these, the
arrangement of this kilp, with the application of the "gazogene," has also the great
advantage of burning the products subjected to this process in a uniform manner
by reason of the facility of directing the flames at one time to the right side, and
at another to the left side of the products to be burnt, by working the emission
doors in one direction or the other as often as judged to be required.
It is of course understood that in order to facilitate the flames passing through
the whole of the mass to be burnt that some little flues or apertures should he
formed in the mass, chiefly on the sole or bottom of the waggon, and corresponding
with the flame apertures or mouths.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edgar Edmonds in the Great Seal Patent Office on the 5th August
1881.
EDGAR EDMONDS, of the Firm of Robertson, Brooman, and Company, of
166, Fleet Street, in the City of London, Patent Agents. "IMPROVEMENTS IN
AND ADDITIONS TO KILNS FOR BURNING OR BAKING CEMENTS, GYPSUM, LIMES,
BRICKS, TILES, POTTERY, AND OTHER SIMILAR SUBSTANCES." (A communication
from abroad by Charles Amand, Engineer, of 22, Rue du Chateau, Tournay,
Belgium).
The improved kiln which forms the object of the present Invention is composed
of two principal parts or elements, viz., the kiln proper and the " gazogene."
It is clearly represented in the annexed Drawings, Figure 1 being a plan,.
Figure 2, a section through A, B; Figure 3, a section through C, D; Figure 4, a
section through E, F, G, H; Figure 5, a section through J, K; and Figure 6 being
a view in elevation from the chimney side.
The Kiln The kiln is composed of a gallery or bricked chamber A 15.05 metres
long by 3.04 metres interior width, or of such other length as may be required
according to the class of matter to be burnt or calcined. This gallery or chamber
is constructed on walls of masonry B arranged in such manner as to permit the
circulation of atmospheric air under the sole or bottom C of the kiln, and thus
maintain a low temperature at the metallic parts of the waggons or trucks.
gallery or chamber contains, say, 5 waggons or trucks D, each 3 metres in length,
and their bottoms or platforms, which are made of refractory bricks or blocks, form
the sole or bottom C of the kiln.
The
Any other number of trucks may be of course employed, according to the
material being baked or calcined. The waggons or trucks run on iron rails E
1.50 metres apart or gauge from axis to axis, the said rails resting on longi-
tudinal sleepers of oak, which are imbedded in and supported by walls of
masonry F.
The waggons or trucks are fitted with sides G of refractory material 0.20 metres
wide at the base and 0.10 metres wide at the top, and rest on the platform (or sole
of the kiln) and rise up to the spring of the gallery arch H. These refractory sides
which prevent the products from falling against the walls of the gallery or chamber,
especially in the case of cement or of lime, are pierced with holes or apertures I,
through which the flames pass and penetrate into the mass of the products to be
burnt, and leave by the opposite side of the waggon after having followed a course
or direction normal to the longitudinal line of the kiln.
Two sliding doors J and K fitted with equilibrium counterweights, which enable
the rapid raising and lowering of them for opening and closing, are placed one at
the entrance and the other at the exit from the gallery or chamber. Perfect closing
is effected by rapidly luting with clay. At the middle of the length of and under
the gallery are arranged four "recuperators" of heat L, L, L, L, placed two by two
at each side. Each group of two comprises one "recuperator" for air and one for
gas. Above each of them are arranged twelve flues M, which terminate in mouths
or apertures placed on the same level at the upper surface of the sole. When the
hot air and the heated gas leave these mouths or orifices they ignite, and the flames
after having passed through the products to be burnt are sucked or drawn into the
mouths or orifices of the opposite group of "recuperators" passing through them
from top to bottom and heating them, and from thence they pass to the draught
chimney after passing the distribution doors, and the horizontal chimney placed in
front of the "recuperators." Each group of two "recuperators" is at one time an
emission group, and at another time an exit or draught group, and to effect

page_text: this change in the action all that is required is to work the distribution doors of
air and gas, which are placed in front of the “recuperators" in the distribution
chamber.
Along the longitudinal walls of the gallery are embedded two sheet iron
trenches P containing sand, into which dip or plunge the sheet iron plates carried
on each side of the waggons under the sole. These sand trenches and iron plates
thus form a longitudinal joint on each side and along the whole length of the gallery
preventing any penetration of the atmospheric air into the gallery above the sole of
the kiln.
In front of and along the whole width of each waggon is an iron bar R fixed
to the iron frame of the waggon. This penetrates into two other iron bars S
arranged in the same way at the back part of the preceding waggon, clay being
placed between them.
A hermetic joint is thus established between each waggon.
It will thus be seen that longitudinally and transversely between each waggon
likewise at the entry and exit to the gallery or chamber, there is perfect and
complete isolation of the upper part of the gallery or chamber above the sole
which is hot from the under part which is in communication with the
atmosphere.
A winch (not shown in the Drawings) is placed at the exit or outlet from the
kiln, and is so arranged that ten revolutions of the crank will cause a forward
movement of exactly three metres or the length of one waggon to be imparted to the
five waggons inside the kiln.
The railway under the kiln on which the waggons run has an incline of 0.007
metre per metre from the entrance to the outlet or exit. This incline has been so
calculated as to equilibriate the resistances of friction and of inertia of the train
of five waggons.
Should the length of the kiln be increased or diminished, and consequently
the number of waggons be altered, then this incline must be modified accordingly.
The "Gazogene." -The "gazogene," which is employed in connection with the
present Invention, is that known as the "Siemen's" system.
It is placed at the side and at the back of the kiln, and is seen in Figure 1. The
gases are conducted to the distribution doors by an iron pipe T.
It has been observed from what has been described above how these gases com-
bined with air arrive at the mouths or apertures where they ignite, after having
previously and in a separate state passed through one or other of the "recuperator
groups.
Action of the Apparatus.-The following is the method of action in the case of a
kiln for burning cement:-
After the kiln has been well dried four empty waggons and a fifth carrying the
products to be burnt, about 16,000 kilogrammes are successively introduced through
the entrance door, the luting is effected and the heating is commenced, which is
gradually augmented.
When it is known that the first charge is sufficiently dry, the doors are opened
and an empty waggon is withdrawn at the outlet end at the same time that a fresh
load of products is introduced at the other end. The heating is then brought up to
its full force, and when the products previously dried are judged to be sufficiently
calcined the foregoing manoeuvre is repeated, which brings the first charge or load
in front of the flame apertures or mouths. At this moment the products carried by
the waggon in front of the flame apertures or mouths are calcined and about to be
burnt; the products carried by the waggon immediately behind are dried and
about to be calcined, and finally the products just introduced are still wet and are
about to be dried.
To effect these operations the distribution doors are opened further so as to
augment the flames which burn the products placed on the waggon in front of the
flame apertures or mouths, the flames penetrating the products transversally and
imparting to them a large part of their heat. After leaving this mass of products

page_text: the flames are drawn into the opposite group of "recuperators" in direct communi-
cation with the draught chimney.
After a certain lapse of time the products placed on the waggon in front of the
flame apertures or mouths are completely burnt, and a fresh charge or load is
introduced which forces the first charge beyond the flames, where it gradually cools
until the time it is withdrawn. It will be seen that this movement of waggons is
most simple.
In consequence of the arrangement of this kiln and of the manner in which the
mass to be burnt is distributed the flames completely embrace the latter, and the
exact temperature required for burning Portland cement is thus obtained. This
temperature is ascertained by a pyrometer, and maintained by opening the distri-
bution doors more or less.
The mass to be burnt is thus exposed to a temperature of from 400 to 500
degrees of drying; for calcining it is exposed to a bright red heat; and finally it
is exposed in front of the flame apertures or mouths at a white heat, where it is burnt.
When products other than cement are to be burnt the exact degree of tempera-
ture suitable for them is obtained by opening the distribution doors more or less,
and in like manner they may be submitted to the direct action of the flames more
or less slowly and be allowed to cool more or less rapidly after the burning by
lengthening or shortening the gallery of the kiln, which in all cases contains as
many waggons as there are number of times three metres in its length.
For burning bricks the long and costly operation of preparatory drying may be
dispensed with by constructing a very long gallery, and thus their manufacture inay
be carried on in winter equally well as in summer and in any weather.
In this case and to facilitate this progressive drying in the kiln previous to
burning, instead of allowing the hot gases to proceed to the chimney after leaving
the draught or suction set of "recuperators," they are caused to return into the kiln
at the entrance end by means of a flue penetrating into the kiln at about eight metres
from the last flame apertures or mouths. The gases thus pass through and dry the
last products introduced, and from thence pass to the chimney through a flue formed
in the arch of the kiln near the entrance.
It is sometimes desirable. in the case of certain products, such as bricks, that two
waggons should be submitted to the direct action of the flames at the same time; the
flame apertures or mouths are then extended to twice their ordinary length, that is
to say, to 6 metres long.
In addition to the important advantages of a continuous burning, of imparting
the exact temperature necessary for the burning of various kinds of products, and
of progressively bringing the products up to the temperature for burning, as also in
cooling them progressively according to their nature; in addition to these the
arrangement of this kiln with the application of the "gazogene" has also the great
advantage of burning the products subjected to this process in a uniform manner by
reason of the facility of directing the flames at one time to the right side, and at
another to the left side of the products to be burnt by working the emission doors
in one direction or the other, as often as judged to be required.
It is of course understood that in order to facilitate the flames passing through
the whole of the mass to be burnt that some little flues or apertures should be
formed in the inass, chiefly on the sole or bottom of the waggon and corresponding
with the flame apertures or mouths.
In witness whereof, I, the said Edgar Edmonds, have hereunto set my hand
and seal, the Fifth day of August, One thousand eight hundred and eighty
EDGAR EDMONDS. (L.S.)