Improvements in Kilns for Burning Cement.
Year: 1899

page_text: Date of Application, 13th Mar., 1899-Accepted, 10th June, 1899
Improvements in Kilns for Burning Cement.
I, PAUL OTTO VON KROTTNAURER, of 22, Klopstockstrasse, Berlin, in the German
Empire, Cement Expert, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement:→
This invention relates to a kiln or oven for burning cement and consists of the
improvements hereinafter described.
In the accompanying drawings,
Figure 1 is a vertical section through a kiln constructed according to the
invention;
Figure 2 is a section on the line 1-1 Figure 1;
Figure 3 is a section on the line 2-2 Figure 1;
Figure 4 is a section on the line 3-3 Figure 1;
Figure 5 is a section on the line 4-4 Figure 1; and
Figure 6 illustrates a detail drawn to a larger scale.
The improved kiln comprises the burning shaft proper a and the cooling shaft b.
The cooling shaft b is forined of an iron basket which permits cooling air to flow in
every direction into the well burnt cement. The basket is built of T-iron bars, c, c, c
rivetted to channel or U-iron rings d, d', du, d¹¹. The basket is contracted at its
lower end and is suspended from columns e which simultaneously serve as supports for
the burning shaft. The T-iron bars are rivetted to the rings by the removal of the
rib or web at the point of junction with the rings as shewn in Figure 6.
The chief feature of the invention is the iron tube or pipe f which is arranged in
the centre of the oven or kiln. The said pipe f is maintained full of water in the
burning zone during the operation of the kiln. At the lower part of the pipe where
the burning zone ceases a thinner tube g is introduced, the thickened flange of
which tube forms the bottom for the water chamber in the pipe ƒ. The tube g
is arranged in connection with a water container h having a gauge pipe i fitted
to it. The pipe f is closed at its upper end by a flanged tube k which is of
the same diameter as the tube g. The tube k is provided with a lateral branch
which is in communication with the container h. The open end of the tube k
extends into the chimney and serves for increasing the draught. The kiln is
closed at its bottom end by an iron cone m upon which the lower end of the
pipe fis supported; the said pipe f is at its upper part held by the arms 0.
The chimney n rests upon the cone p which is provided with several doors p¹, p",
pp for enabling the kiln to be easily charged.
The operation of the kiln is as follows:-
After the water reservoir h has been filled, the cooling basket 6 is charged with
cement clinkers, or, if such are not at hand, with limestone.
A thicker layer of easily combustible material is then packed upon this cement or
other layer and the shaft a is alternately charged with raw cement and fuel. The
easily combustible fuel is then ignited. The fire gradually ignites the layers of
fuel, whereby the raw cement stone is well burnt. During the burning operation
the pipe f, which is cooled with water, cools the centre of the glowing cement

page_text: cylinder. The steam generated rises through the tube k and produces a considerable
draught in the furnace. As soon as the charge sinks fresh fuel and raw cement stone
are filled in from above through the doors pl, pl, pl, p and the burnt cement is
from time to time removed from below.
The iron pipe guides the hollow cement cylinder which is formed and enables the
latter to be easily broken up, for as soon as the hollow cylinder comes to rest upon
the iron cone in the said cylinder is split and broken up by the weight of the charge
resting upon its upper end. The pieces of burnt cement clinker can then be easily
removed.
Instead of charging the burning shaft a alternately with fuel and material to be
burnt, lateral firing can be provided in the well known manner.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed, I declare that what I
claim is :-
1. A cement kiln or oven through the centre of which there passes an iron pipe fƒ
containing water and resting upon a supporting cone m and adapted to cool the cement
clinker cylinder which is formed, the steam developed from the water being utilized
for increasing the draught, substantially as herein before described and illustrated in
the accompanying drawings.
2. The combination and arrangement of parts forming the improved kilns herein-
before described and illustrated respectively in Figures 1 to 6 and 7 of the
accompanying drawings.
Dated the 13th day of March 1899.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.