IMPROVEMENTS IN OVENS AND KILNS FOR DRYING AND BURNING BRICKS AND OTHER ARTICLES
Year: 1867

page_text: the
PROVISIONAL SPECIFICATION left by the said Jacob Buhrer at the
Office of the Commissioners of Patents, with his Petition, on
28th February 1867.
I, JACOB BUHRER, of Munich, in the Kingdom of Bavaria, but now of
Keppel Street, in the County of Middlesex, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN OVENS AND KILNS FOR DRYING AND
BURNING BRICKS AND OTHER ARTICLES." to be as follows:-
My Invention in so far as it relates to ovens for drying bricks and other
articles consists in constructing them in a series of rectangular compartments
placed side by side in two rows, the two rows being set back to back, and in
connecting each compartment with those next adjoining by openings in the
dividing walls; and in the arrangement of flues and dampers, as hereafter
described, whereby I am enabled to regulate the supply of heat to the com-
partments for the purpose of carrying on a particular process of drying, as
hereafter explained. Each compartment is as before mentioned rectangular,
the side walls being preferably much longer than the end walls, so that there

page_text: may be only a small surface exposed to the outer air. The side walls each
have an opening alternately at the back and front. communicating between
the adjoining compartments, and the end compartments of one row com-
municate with the end compartments of the other row by openings in the
middle wall these openings are thus so arranged that were they all unenclosed
there would be a zig-zag passage for a current through the compartments in
the one row which would be continued by a zig-zag passage in the opposite
direction through the compartments in the other row: the openings are how-
ever provided with doors or dampers which can be opened and closed as
required as the drying process is being carried on. Under the middle wall
two flues are formed, one for the heated air and the other for the escape air;
two similar flues are formed under each of the two outer side walls of the
oven these fiues each communicate with the various compartments, the
communications being provided with dampers. This oven is preferably built.
at the end of the kiln, hereafter described. from which it receives the heated
air necessary for drying the bricks or other articles.
The process of drying in this oven is as follows:-1 divide the compartments
into, say, sets of five; No. 1 of each set will contain nearly dry bricks: No. 2.
half-dried bricks: No. 3, green or wet bricks: No. 4 will be cooling while
No. 5 is being emptied and refilled. The necessary dampers are open to allow
the hot air from the burning kiln to enter No. 1, to pass from thence at a
diminished heat to No. 2, and then at a still less heat to No. 3. from which it
issues by one of the escape flues; after a certain time the bricks in No. 1 will
be quite dry, No. 2 nearly dry, and No. 3 half dry; I then close and open the
necessary dampers and doors to make No. 2 of each set No. 1, or the com-
partment which first receives the hot air: No. 3 will thus become No. 2;
No. 4 No. 3; No. 5 No. 4: and No. 1 of the set in front. will become No. 5
of the first set. No. 1 of the first set becoming No. 5 of the set behind. The
operation is thus carried on continuously through the whole series of, say, 20
or other convenient number of compartments of the oven. The draught may
be increased by a fan or ventilator at the end opposite the kiln or otherwise.
Another improvement in the oven consists in forming the side walls of the
compartments with projecting bricks to receive and support trays or frames,
upon which the bricks are introduced through doors at the froni. Instead of
the hot air passing through three compartments while two compartments are
shut off, making five compartments in one set. these numbers may be varied
and the dampers and doors regulated accordingly.
My Invention so far as it relates to kilns consists in constructing them in a
similar manner to the oven of a series of rectangular compartments built side

page_text: by side in two rows set back to back. As the thrust resulting from the
expansion of the brickwork will only be towards the ends of the rows these end
walls will be constructed of the necessary thickness with supporting piers while
the intermediate walls may be comparatively thin; according to this construction
there will be little exposure to the air, and therefore little loss of heat. The
compartments communicate with each other like those of the oven, and there
are flues and dampers to enable them to be worked progressively and con-
tinuously in an analogous. manner to the oven. The compartments are
supplied with fuel from the top, by preference in the state of fine division, in
which the combustion is effected in the manner described in the Specification
of a Patent granted to Francis Wise, on the 4th of April 1866, No. 956.
The supply of fuel may be regulated by the apparatus described in the
Specification of a Patent granted Astley Paston Price, on the 12th of May
1866, No. 1865. The heated air after leaving the kilu is as before stated
conducted to the drying oven so that its heat is utilized. A chimney for down
draught may be fitted to the kiln.
SPECIFICATION filed in pursuance of the conditions of the Letters Patent,
and of an Order of the Lord Chancellor, by the said Jacob Buhrer in
the Great Seal Patent Office on the 24th September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JACOB
BUHRER. of Manich, in the Kingdom of Bavaria, lately residing at Keppel
Street, in the County of Middlesex, but now residing at Elofen, near Schaff-
hausen, Switzerland. send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent. bearing date the Twenty-eighth day of February, in the year of our
Lord One thousand eight handred and sixty-seven, in the thirtieth year of
Her reign, did, for Herself. Her heirs and successors, give and grant unto nic,
the said Jacob, Buhrer. Her special licence that I, the said Jacob Buhrer.
my executors, administrators, and assigns, or such others as I, the said Jacob
Buhrer, 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
OVENS AND KILNS FOR DRYING AND BURNING BRICKS AND OTHER ARTICLES," upon
the condition (amongst others) that I, the said Jacob Buhrer, my executors

page_text: 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 J. the said Jacob Bührer, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, that is to say:-
The chief object of this Invention is to construct ovens and kilns for carrying
on a particular mode of effecting the combustion of the fuel; and in order that
this object may be fully understood I will first describe the mode in which the
combustion of the fuel is effected, although this mode forms the subject
of a separate Patent granted to Francis Wise on the 4th April, 1866,
No. 956.
The fuel which I employ consists of coal, anthacite, coke, shale, peat, or
other like matter in as fine a state of division as it is practicable to obtain it;
this fuel in a state of powder or dust is allowed to fall through a suitable
orifice in such a way that the supply or flow of the powder can be regulated
into a space in the oven or kiln where it meets air previously heated, and
whilst in the act of falling it takes fire, and is consumed whilst suspended in
the air, thereby undergoing the most perfect. combustion; this mode of applying
the fuel resembles, in fact, the burning of gas with this difference, that the
gas is generated in this instance at or near the place where it is to be burnt, a
draught carrying the burning particles of fuel along into the spaces left between
the bricks or other articles, a perfect and uniform heat is obtained, which can
be regulated with great facility, and which insures the bricks or other articles
to be burnt receiving an uniform temperature throughout and in every part of
the kiln, which is an object of the greatest importance not previously obtained
by any other means or contrivance. The supply of the powdered fuel may be
regulated by the apparatus described in the Specification of a Patent granted
to Astley Paston Price, on the 12th May. 1866, No. 1365.
For the purpose of economizing the heat given off in the process of burning
1 make use of a kiln of a peculiar construction, which whilst it admits à
continuous process of burning is so arranged as to allow part of the heat
retained in the burnt articles to be drawn away along with the gaseous
products of the combustion by means of a ventilator, or fan, or chimney,
through a series of drying chambers in which the bricks are thus economically

page_text: dried to such a degree that they are almost absolutely free of water previous
o their being put into the kiln. From the description of the oven and kilns
hereafter given it will be perceived that by this mode of working nearly the
whole amount of heat generated by the fuel, is utilized, and in the case where
a fan is used it has been found that the moist air which issues from the fan is
only about from 60° to 75° Fahrenheit higher than the ordinary temperature
of the atmosphere.
I now proceed to describe the construction and operation of the ovens and
kilns.
My Invention in so far as it relates to ovens for drying bricks and other
articles consists in constructing them in a series of oblong rectangular com-
partinents, placed side by side in two rods, the two rows being set back to
back; in connecting each compartment with those next adjoining by openings
in the dividing walls, and in the arrangement of flues, doors, and dampers as
hereafter described, whereby I am enabled to regulate the supply of heat to
the compartments for the purpose of carrying on a particular process of drying,
as hereafter explained.
My Invention in so far as it relates to kilns consists in constructing them
in a similar manner to the ovens of a series of oblong rectangular compartments
built side by side in two rows set back to back; the compartments com-
municate with each other like those of the oven, and there are flues, doors, and
dampers to enable them to be worked in a similar manner to those of the oven.
As the thrust resulting from the expansion of the brickwork will only be
towards the ends of the rows these end walls are constructed of the necessary
thickness with supporting piers, while the intermediate walls may be com-
paratively thin; according to this construction there will be little exposure to
the air. and therefore little loss of heat, and a great economy in brickwork will
he effected:
My, Invention will be, fully understood; by the annexed Drawings and the
following description thereof.
Figure 1 is a general plan or view of the system of drying and burning
combined; Figures 2 and 3 are sections respectively through the lines F, K,
and G. II, of Figure 8; Figure 4 is an elevation of the end A, B, of Figure 8;
Figure 5, an elevation of the side B, E. of Figure 8; Figures 6 and 7 are
sections respectively through the lines L. M, and. C. D, of Figure 8; and
Figure 8 is a plan of the drying oven and kiln combined. This Figure is in
section except at the parts marked S, T, and R, Q...
I will first describe the drying oven. It consists, as before mentioned and
as seen in the Drawings, of a series of oblong rectangular compartments set

page_text: side by side in two rows, which are set back to back. I have shown 24 com-
partments, but any other convenient number may be employed. The side
walls of each compartment have openings h alternately at back and front, as
shown, communicating with the next adjoining compartments, and the end
compartments of one row communicate with the end compartments of the
other row by openings in the middle wall. The openings are thus so
arranged that were they all unclosed there would be a zig-zag passage for a
current through the compartments in one row, which would be continued by
a zig-zag passage in the opposite direction through the compartments in the
other row: the openings h are however provided with doors or dampers, as
represented at v, r, Figure S, which can be opened and closed as required as
the drying process is being carried on. Under the middle wall two flues are
formed, one marked for the heated air for drying the bricks, and the other
marked for carrying off the air after leaving the bricks; two similar flues
are formed under each of the two outer side walls of the oven, viz, a flue e for
the heated air, and one d for escape air under the wall to the left of Figure 2;
and a flue e for heated air, and one for escape air in the wall to the right of
Figure 2. These flues communicate with the various compartments, that is to
say, every compartment is in communication with one heated air flue and with
one escape air flue; this arrangement or system will be understood by
Figure 8, in which m, m, are the communications with the escape air flues,
and n, n, the communications with the heated air flues. The escape air flues
are colored green, and the heated air flues red. The communications m and n
are each provided with a door or damper opened and closed as the progress of
the drying process requires. V is a ventilator or fan for exhausting the air
from the escape air flues; and P is a furnace for heating and assisting the
draught through the heated air flues with which it is in communication by
short flues, as indicated in Figure 8. The heated air and draught are,
however, chiefly derived from the kiln, which is in communication at the
point 1, Figure 8, with the heated air flues b, c, and e. Each compartment
has an opening g at the froni provided with a door or damper.
The process of drying in this oven, constructed with flues as before described,
is carried on as follows, and will be understood on reference to Figure 1. I
divide the compartments into, say, sets of five; No. 1 of each set will be in course
of being emptied and refilled through the door at its front, No. 2 will be cooling
by means of air admitted through No. 1, No. 3 will contain nearly dry bricks,
No. 4 half-dried bricks, and No. 5 green or wet bricks. The necessary
dampers and doors are open to allow the hot air from the kiln to enter No. 3.
of each set, to pass from thence at a diminished heat to No. 4, and then at a

page_text: still less heat to No. 5, from which it issues by one of the escape flues. After
a certain time the bricks in No. 3 will be quite dry. those in No. 4 nearly
dry, and those in No. 5 half dried. while No. I will have received fresh green
bricks, and the bricks in No. 2 will be sufficiently cooled for removal; I then
close and open the necessary dampers and doors to make No. 4 of each set
No. 3. or the compartment which first receives the hot air; No. 5 will thus
hecome No. 4: No. 1 of the set in front will become No. 5 of the first set;
No. 3 of the first set will become No. 2; No. 2 will become No. 1; and No. 1
will become No. 5 of the set behind. The operation is thus carried on con-
tinuously through the whole series of compartments of the oven. The red
arrows in Figure I show the direction or course of the hot air, and the green
arrows that of the escape air. Instead of the hot air passing through three
compartments while two compartments are shut off, making five compartments
in one set, these numbers may be varied, and the dampers and doors regulated
accordingly.
I now proceed to describe the kiln to the compartments of which the bricks
are removed after being dried in the oven. The kiln shown has twelve compart-
ments, which I consider a convenient number: there is one central flue with
which every alternate compartment communicates through openings c' provided
with dampers; the compartments communicate with each other by openings
e in the dividing walls, and every alternate opening e' is provided with a door
or damper actuated from the top. as indicated by b'. Figure 8; it will thus be
understood that these compartments are arranged as it were in pairs; the
several pairs are worked progressively and continuously in an analogous
manner to that before described in reference to the oven. Each compart-
ment is provided with an opening d' at the front fitted with a door or damper.
The compartments are fed with fuel from the top through apertures a¹; this
fuel is in the state of fine division, and as it falls through the bricks the com-
bustion is effected by the great heat of the bricks themselves which have
previously been heated by the products of combustion from the compartments
behind.
On reference to Figure 1 it will be seen that the doors at the front of
compartments 1 and 2 are open, and that fuel is being fed to 8; 3, 4, 5, 6,
and 7 have previously been burnt, and 8, which is now being fed, has been made
so hot by the products from those behind that the powdered fuel supplied to it
is at once consumed. No. I is being emptied and refilled, cold air is rushing
through No. 2 to cool the bricks therein, and after passing through 3, 4, 5,
and 6 a portion of it issues in a heated state through the apertures c¹ of 6
into the flue below to go to the oven, while the remainder proceeds through

page_text: 7 to 8 to support the combustion therein; the mode of drawing the cold air
through the hot bricks in 3, 4, 5 and 6. and through the aperture c¹ direct to
the drying compartments affords great advantages. The heat and products
of combustion from 8 pass through 9, 10, 11, 12, and heat or partially
burn the bricks therein, and finally issue in a heated state by the apertures
c' of 12 into the flue below leading to the oven. When the bricks in
No. 8 are sufficiently burnt the necessary doors and dampers are closed
and opened to admit of the same process being carried on from No. 9
which is then supplied with fuel: the door of No. 3 is opened to admit
cold air, and the dampers in 8 is opened to allow a portion of this air
after being heated while passing through 4, 5, 6, 7, and 8 to issue into the
central flue. The same process is carried on continuously and progressively
through the series of compartments. In burning pottery and other articles
when it will be injurious to allow the fuel to come in contact therewith a space
may be left unfilled in each compartment of the kiln, into which space the fuel
is dropped and consumed in the manner before explained. a, b, is a flue or
channel above the compartments to allow of air entering it and passing after
being heated into the flues of the oven. The top of the kiln is filled in with
clay or other suitable material to prevent loss of heat as much as possible. It
will be observed that very little surface of each compartment is exposed to
the outer air, that the inner walls can be comparatively thing owing to the
arrangement of the compartments, and that the two end walls are of the
necessary thickness to resist the force of expansion exerted by the heat; the
end wall farther from the oven is supported by piers, as seen in Figure 4 while
the farther end of the oven is similarly supported. U is a chimney communi-
cating by a flue with the kiln; this chimney may be employed for producing
draught when a ventilator is not used:
. And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I do not claim as my present
Invention the particular mode of effecting the combustion of fuel in a
state of fine powder, because, as before stated, this forms the subject of prior
Letters Patent; neither do, I claim the progressive and continuous manner of
drying the bricks or of burning the bricks when dried, as this process is very
old. Jn 184 one Joseph Gibbs obtained Letters Patent for England for a
kiln constructed in a circular or annular form divided into a series of com
partments with fines leading to one central chimney, and the process of burning
was progressive and continuous as in my kiln and oven. In fact, the old
common mode of burning bricks in stacks in the open air is progressive,
because as the fire is lighted at the bottom the lowest layer of bricks is. burnt first:

page_text: the fuel above them then becomes ignited and burns the next layer of bricks.
and so on progressively to the top. I do not, therefore, I say, claim the mode
of burning or drying bricks in a progressive or continuous manner, but what I
claim is my Invention of improvements in oven and kilns for drying and
burning bricks and other articles is,-
First, the construction of ovens and kilns for drying and burning bricks
and other articles, substantially as herein-before described and represented in
the accompanying Drawings of a series of oblong rectangular compartments
in two rows, which are set back to back. whereby the intermediate walls may
be made comparatively thin, only the two outer end walls being made of the
necessary thickness and strength to support the thrust due to expansion..
Second, the construction of ovens and kilns for drying and burning bricks
and other articles. and which are composed of a series of rectangular com-
partments in two rows set back to back with the necessary flues, openings,
doors, dampers, and communications substantially as herein-before described
and represented in the accompanying Drawings for carrying on the particular
mode of effecting the combustion of the fuel and the progressive and continuous
mode of drying and burning herein-before explained.
Third, the combination, substantially as herein-before described and repre-
sented in the accompanying Drawings, of a drying oven and a burning kiln,
so that the heat from the latter is utilized in the former, as herein-before
explained.
In witness whereof, I, the said Jacob Buhrer, have hereunto set my
hand and seal, this Twenty-eighth day of August, in the year of our
Lord One thousand eight hundred and sixty-seven.
JACOB BUHRER. (L.S.)