IMPROVEMENTS BURNING CEMENT, AND IN KILNS EMPLOYED FOR THAT PURPOSE
Year: 1879

page_text: LETTERS PATENT to Henry Simon, of No. 7, St. Peter's Square, Manchester,
IN
A
in the County of Lancaster, for the Invention of "IMPROVEMENTS
BURNING CEMENT, AND IN KILNS EMPLOYED FOR THAT PURPOSE."
communication from abroad by Wilhelm Michaelis, of Berlin, in the German
Empire.
Sealed the 4th April 1879, and dated the 30th January 1879.
PROVISIONAL SPECIFICATION left by the said Henry Simon at the Office
of the Commissioners of Patents on the 30th January 1879.
HENRY SIMON, of No. 7, St. Peter's Square, Manchester, in the County of
Lancaster. "IMPROVEMENTS IN BURNING CEMENT, AND IN KILNS EMPLOYED FOR
THAT PURPOSE." [A communication from abroad by Wilhelm Michaelis, of Berlin,
in the German Empire.]
In burning cement in kilns it has hitherto been the practice to introduce into.
the kilns in the first instance a full charge of alternate layers of fuel and cement,
and then to effect the complete burning of such charge at one operation, a con-
tinuous process of removing the burnt cement from time to time at the bottom,
and the addition of fresh layers of material at top (as in blast furnaces for sinelting
iron) being in this case impossible because the burnt cement solidified to a hard
mass at the bottom of the kiln, which can only be removed after the entire charge
has been burnt and the kiln has cooled down so that access, can be gained to the
interior thereof.
By the above process the great disadvantage exists that only a comparatively
small charge can be treated at one time, as it is found that if a considerable
column of material is introduced in the kiln over the fire at the bottom thereof the
gaseous products of combustion in becoming cooled by contact with the cold upper
portion of the charge seriously impede the process of combustion below, creating an
excess of pressure, which prevents the necessary draught of air through the kiln;
and even with the moderate charges now in use this prejudicial effect is produced
to a great extent.
According to the present Invention the above defects, and the consequent want
of economy in the fuel and loss of time are obviated, firstly, by making the opera-
tion of burning to a limited extent continuous, that is to say, advantage is taken
of the fact that the charge after burning shrinks together to a considerable extent
for the purpose of introducing into the kiln after the first charge has been burnt to
a certain extent additional charges, which are then burnt together with the first
rn

page_text: charge, and the whole being afterwards removed when the operation has been
completed. Secondly, in_order_to_prevent the choking of the draft at the com-
mencement of the firing, such as has been above alluded to, and also to allow of
the introduction of the additional charges, I provide at the sides of the kiln one or
more (by preference four) auxiliary chimnies, which are made to communicate with
the interior of the kiln at an intermediate point of its height, so that the products
-of-combustion-from-the-fire below are during the first part of the operation drawn
off-through-these chimnies instead-of-having to penetrate-through-the whole upper-
mass of the charge as heretofore, in order to pass off at the main chimney. By
this means a brisk combustion is at once produced at the lower part of the charge,
whereby the latter becomes rapidly heated, and in sinking together permits of the
introduction of the additional charges through side openings in the kiln, the
absence of the gaseous products of combustion in the upper part of the kiln
allowing the workmen to have free access thereto for that purpose. The said side
chinies are by preference heated by separate fires during the first part of the
time they are in operation in order to accelerate the draught through them, or a
steam or air jet may be introduced in them for this purpose. When the additional
charges have been introduced, and the zone of combustion has risen to the level of
the openings into the side chimnies, these are closed by means of valves or dampers,
and the burning of the entire charge is then completed by the draught through the
main chimney in the ordinary way; the latter is also provided with a damper for
regulating the draught through it.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Simon in the Great Seal Patent Office on the 23rd April
1879.
HENRY SIMON, of No. 7, St. Peter's Square, Manchester, in the County of
Lancaster. "IMPROVEMENTS IN BURNING CEMENT, AND IN KILNS EMPLOYED FOR
THAT PURPOSE." A communication from abroad by Wilhelm Michaelis, of Berlin,
in the German Empire.
In burning cement in kilns it has hitherto been the practice to introduce into
the kilns in the first instance a full charge of alternate layers of fuel and cement,
and then to effect the complete burning of such charge at one operation, a con-
tinuous process of removing the burnt cement from time to time at the bottom,
and the addition of fresh layers of material at top (as in blast furnaces for smelting
iron) being in this case impossible, because the burnt cement solidified to a hard
mass at the bottom of the kiln, which can only be removed after the entire charge.
has been burnt and the kiln has cooled down so. that access can be gained to the
interior thereof.
By the above process the great disadvantage exists that only, a, comparatively
small charge can be treated at one time, as it is found, that if a considerable,
column of material is introduced in the kiln, over the fire. at the, bottom, thereof,
the heavy gaseous products of combustion becoming cooled by contact, with the
cold upper portion of the charge seriously impede the process of combustion below,
creating an excess of pressure which prevents, the necessary draught of air through,

page_text: the kiln; and even with the moderate charges now in use this prejudicial effect is
produced to a great extent.
According to the present Invention the above defects and the consequent want.
of economy in the fuel and loss of time are obviated, firstly, by making the opera-
tion of burning to a limited extent continuous, that is to say, advantage is taken
of the fact that the charge after burning shrinks together to a considerable extent
for the purpose of introducing into the kiln after the first charge has been burnt to
a certain extent additional charges, which are then burnt together with the first
charge, and the whole being afterwards removed when the operation has been
completed. Secondly, in order to prevent the choking of the draught at the com-
mencement of the firing, such as has been above alluded to, and also to allow of the
introduction of the additional charges, there are provided at the sides of the kiln
one or more (by preference four) auxiliary chimnies, which are made to com-
municate with the interior of the kiln at an intermediate point of its height, so
that the products of combustion from the fire below are during the first part of the
operation drawn off through these chimnies instead of having to penetrate through
the whole upper mass of the charge as heretofore in order to pass off at the main
chimney. By this means a brisk combustion is at once produced at the lower part
of the charge whereby the latter becomes rapidly heated, and in sinking together
permits of the introduction of the additional charges through an upper side.
opening in the kiln, the absence of the gaseous products of combustion in the upper..
part of the kiln allowing the workmen to have free access thereto for that purpose.
The said side chimnies are by preference heated by separate fires during the first
part of the time they are in operation in order to accelerate the draught through
them, or a steam or air jet may be introduced in them for this purpose. When the
additional charges have been introduced, and the zone of combustion has risen to.
the level of the openings into the side chimnies, these are closed by means of valves,
dampers, or doors, and the burning of the entire charge.is then completed by the
draught through the main chimney in the ordinary way; the latter is also provided
with a damper for regulating the draught through it.
The accompanying Drawings shew a construction of kiln according to this Inven-
tion suitable for conducting the process of cement burning as above described.
Figs. 1 and 2 are vertical sections respectively on the lines E, F, and G, H, of
Figs. 3 and 4, which are sectional plans respectively on the lines C, D, and A, B, of
Figs. 1 and 2. The body A of the kiln tapers to a larger diameter downwards,
becoming contracted at the bottom to the fire-grate B, beneath which is a side
opening C for admission of air and for discharging the contents of the kiln after
they are burned. The upper part of the kiln tapers inwards to a central chimney D
provided with a damper. About the middle height of the kiln there are side
openings to the chimnies E, E, each of which is also provided with a damper.
There are two feeding platforms or stages, the lower one F having a side opening F'
into the kiln for charging it in the first place with material up to about the middle
of its height, and the upper stage G and side opening G' for completing the charge
of the kiln as well as for introducing the above-mentioned additional charges, when,
by the process of burning, the original charge has become reduced in bulk and has
consequently sunk down. On the upper stage G are fixed stoves H having their
flues opening into the chimnies E, E, so that the hot products of combustion from
these stoves may cause a draught in the chimnies E, E, and thereby accelerate the
combustion in the first charge of the kiln. The operation of the kiln thus con-
structed is as follows:-The kiln being fully charged with layers of the material to
be burnt, the chimney D and the side feeding openings F' and G' are closed, fires
are kindled in the stoves H and the fuel is kindled on the grate at the bottom of
the kiln. The combustion proceeds in the mass, the zone of combustion rising
gradually in it while it contracts and subsides. Fresh supplies of material and fuel

page_text: are from time to time fed in through the upper opening G' until the burnt contents
_of_the_kiln reach the openings to the side chimnies. The dampers of the chim-
nies.E, E, are then closed, and the damper of the central chimney D is opened, and
the burning of the entire charge is then completed in the ordinary way. The
contents are then allowed to cool, and' are broken up and removed by the side
Lopening-C. In the above-described operation it will generally be found that the
-first additional charge may be added after the original charge has been burning
from 12 to 20 hours, and the further charges may be added at intervals of about
20 hours, assuming the kiln to be of ordinary size. It will be evident that the
above-described construction of kiln with lateral chimnies may also be employed
with advantage when working the kiln with a single charge in the ordinary way,
as by this means the combustion will be considerably accelerated during the first
part of the process of burning, and charges of greater height may consequently bo
burnt at one time.
Having thus described the nature of the said Invention, and in what manner
the same is to be performed, as communicated to me by my foreign correspondent,
I claim,
First. The method of burning cement by the introduction of successive charges
into one and the same kiln during the process of burning, at such regulated inter-
vals-that the charge or charges first introduced shall have contracted more or less
in bulk before the next following charge is introduced, substantially as and for the
purposes herein described.
Second. In combination with the process of burning, set forth in the preceding
claim, the provision of means for drawing off the gaseous products of combustion at
an intermediate point in the height of the kiln until the zone of combustion
has reached such height, substantially as and for the purposes herein described.
Third. The construction of cement kiln with chimnies opening laterally from
about the middle of its height in addition to the main central chimney, for the
purpose of drawing off the products of combustion at such height during the first
part of the process of burning, substantially as herein described with reference to
the accompanying Drawing.
In witness whereof, I, the said Henry Simon; have hereunto set my hand and
seal, this Twenty-third day of April, in the year of our Lord One thousand
eight hundred and seventy-nine.
HENRY SIMON. (L.S.)