IMPROVEMENTS IN THE BURNING OF LIME OR CEMENT, AND IN APPARATUS TO BE USED THEREIN
Year: 1876

page_text: LETTERS PATENT to Bristow Hunt, of Serle Street, Lincoln's Inn, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN THE
BURNING OF LIME OR CEMENT, AND IN APPARATUS TO BE USED THEREIN."
A communication from abroad by Ananias Smith, Civil Engineer, of Buffalo,
New York, in the United States of America.
Sealed the 23rd May 1876, and dated the 27th March 1876.
COMPLETE SPECIFICATION filed by the said Bristow Hunt at the Office of
the Commissioners of Patents on the 27th March 1876.
BRISTOW HUNT, of Serle Street, Lincoln's Inn, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN THE BURNING OF LIME OR CEMENT, AND IN APPA-
RATUS TO BE USED THEREIN." A communication from abroad by Ananias Smith,
Civil Engineer, of Buffalo, New York, in the United States of America.
Heretofore the burning of the raw material to produce lime or cement by the use
of coal the principal fuel used has been attended with great loss of such fuel and
irregularity and deterioration of the quality of lime or cement produced, partly
owing to the quality and quantity of coal consumed in a given time, and to the
impossibility of controlling the combustion, so as to insure an even degree of heat,
which is necessary to prevent the product being under or over burnt, and of adapting
the heat to the raw material, which, as is well known, requires a variation in the
degree of heat, as it varies in hardness and other qualities, and to the deterioration
in the quality of the lime or ceinent by the action of the sulphur in the coal, and by
the mingling of the ashes, clinkers, and other deleterious matters therewith. These
disadvantages also exist to a certain extent when the fuel used is wood, as the
quality of the product is then deteriorated by the presence of creosote.
The object of this Invention is to obviate these disadvantages by producing a
perfect combustion and a uniform heat absolutely controllable at will, allowing of
the production and maintenance of a greater or less degree of heat at pleasure,
according to the nature of the raw material to be burned, and other conditions,
insuring an even burning from or by the use of liquid fuel or vapour produced
therefrom, which will not deteriorate the quality of the lime or cement.
The Invention consists,-
Firstly. In a method of burning the raw material, from which the lime or
cement is to be produced, by subjecting the same to the action of heat produced by
Price 6d 1

page_text: E
the active combustion of any suitable liquid fuel or vapour produced therefrom,
which is comparatively free from sulphur, and especially (on account of its com-
parative cheapness) of petroleum or other allied liquid hydrocarbon or vapour pro-
duced therefrom, associated or in combination with steam superheated or not and
with air.
Secondly. In a similarly descriptive method, but in which the quantity of either
or all of the clements of combustion therein specified is controllable.
And, Thirdly. In the apparatus in which the methods are carried into
practice.
Such being the nature and object of the said Invention I will now proceed to
describe more in detail the manner in which the same is to be or may be carried
into practical effect; and in order that the same may be distinctly understood I
have annexed hereunto one Sheet of Drawings illustrative thereof, and have marked
the same with figures and letters of reference corresponding with those in the
following explanation thereof, that is to say:-
On the accompanying Sheet of Drawings Figure 1 represents a vertical section of
a lime or cement kiln, having peculiar combustion chambers, and showing means
for supplying liquid fuel or vapor produced therefrom, steam and air thereto.
Figure 2, a front elevation of Figure 3.
Figure 3, a horizontal section of the kiln, showing also a steam boiler, a tank
for containing liquid fuel or vapour produced therefrom, and a superheater; and
Figure 4, a detached vertical section of one construction of pipes for introducing
steam and liquid fuel or vapour produced therefrom into the combustion
chamber.
A represents the shaft of a lime or cement kiln of any desired and well-known
form, and which is lined with fire-brick at the part with which the intense heat
comes in contact. In lime kilns in which wood is the fuel used the same is
usually consumed in apertures extending from the lines a, b, to the walls of
the shaft.
According to these improvements these apertures are extended by means of a
brick or other addition Y in such a manner as to form combustion chambers C as
shown in Figures 1 and 3.
The accompanying Drawings illustrate the application of four of these channels C,
two on cach side of the kiln, and this is the most preferable number for large kilns.
A larger or smaller number may however be employed depending upon the size of
the kiln. Each of these chambers C is provided with a perforated fire-brick or
other grate surface D, bencath which is an air chamber E, communicating through
an aperture F, controlled by a damper G with the outside of the kiln; H repre-
sents air chambers formed in the said additions Y, extending upward on each sido
of each combustion chamber C, and communicating there with through apertures c
made in the walls I. These apertures should be at least one-fourth of the area of
the walls I, where they form the sides of the chambers C, in order that the air may
readily and freely pass into the latter. These chambers H (the quantity of air
entering which inay be controlled by dampers J) may communicate with the
chambers E, or be independent thereof; and if required one only of them may be
used in connection with each chamber C, but the arrangement shown in Figure 3 is
preferable. L represents a steam boiler of any well-known construction, and Ka
tank for containing liquid fuel or vapour produced therefrom made sufficiently
strong to withstand the same pressure as that of the steam boiler. The liquid
fuel or vapour produced therefrom may be supplied to this tank by any suitable
method. The production of the vapour from the liquid fuel may also be effected by
any suitable apparatus or method. A pipe N communicates between the said boiler
and tank, in order that the steam pressure of the boiler may be used to force the
liquid fuel out of the tank through pipes W1, W, (hereafter described) into the
chamber C. The pipe M is provided with a cock & to shut off communication with
the boiler while steam is being raised, or for other purposes, and to control the
pressure in said tank. A pipe N (provided with cocks e, f,) communicate between

page_text: the boiler and a superheater O, which is connected with a pipe U by means of a.
pipe N. These pipes N, N1, are also connected by a pipe Z provided with a cock g,
upon the closing of which and the opening of the cocks e, f, the steam passes.
through the superheater, and upon the opening of which and the closing of the
cocks e, f, the steam passes directly to the pipe U; this pipe U has connected to it.
a series of pipes U₁, one for each chamber C, and each is provided with a T con-
nection R (see Figure 4), which is connected to its chamber C by means of a pipe S
contracted at the end, which communicates with the said chamber through its outer
wall. Within each connection R is a smaller T connection V, which receives one of
the said pipes W, which are connected through the pipes W₁ with the tank K.
A small pipe X extends from one end of the connection V through the end aperture
of the pipe S; an annular space is thus left between it and the aperture through
which steam may issue. The other end of the connection V is left open.
the pipes U and W is provided with a cock h to control the passage of the steam.
and liquid fuel or vapour produced therefrom. The pipes W¹ and U may terminate
at P, P, or may be prolonged, and supply steam and fuel to two or more kilns.
Each of
It will be seen, on reference to the accompanying Drawings, that the raw
material used to fill the kiln when it is first started will remain unburnt from the
bottom of the shaft up to the combustion chambers, but being a perpetual kiln
this only occurs once a season, and the shaft may at first be filled up to the point
named with a comparatively valueless material, such as rubble stone.
The method of operation is as follows:-The shaft of the kiln is first filled with
the raw material, from which the lime or cement is to be produced, and a small fire
is then kindled in each chamber C. The cocks h and dampers G and J are then
opened, steam being first admitted into the chamber C; then the liquid fuel or
vapour produced therefrom is admitted, and the two associate with air in the said
chambers. An active combustion then takes place; the intense heat generated
acts upon the raw material and burns the same, leaving it comparatively free from
sulphur or ashes. After burning it is removed in the ordinary manner.
This associated use of the liquid fuel or vapour produced therefrom with steam,
either superheated or not at any temperature or pressure and with air in the com-
bustion chambers, allows of the production and maintenance of a perfect combustion
and a uniform heat, which by means of the said cocks and dampers is under
perfect control, as the nature of the raw material or other conditions may require.
The steam passes with the liquid fuel or vapour produced therefrom through the
connections V and pipes X, as well as through the pipes S, into the chambers C.
It, and the liquid fuel or vapour produced therefrom, may however pass through
independent pipes brought into close proximity in the chambers C, or the fuel and
steam pipes may be joined, and the fuel and steam pass through the same pipe
into the said chambers; the air which supplies which latter may also be heated if
required or controlled by a blast.
By means of these improvements the raw material is burned at one operation,
and so produces an even quality of lime or cement, comparatively free from ashes
or sulphur, and with such regularity that the product of a perpetual kiln con-
structed with these improvements is increased about four hundred per cent. over
one of the same size operated in the ordinary manner with coal or wood. There
is also comparatively little smoke produced, so that the quality of the lime or
cement is not thereby deteriorated. The cost of the fuel is also reduced by reason
of the complete control of the draft and of the fuel employed, and the perfect
combustion thereof induced in the combustion chambers.
Having now particularly described and ascertained the nature and object of the
said Invention, together with the manner in which the same is to be or may be
carried into practical effect, I would remark in conclusion that the Invention is
not confined to the exact arrangement and construction of parts shewn on the
annexed Drawings, and which may be varied without departing from the Invention;
but what I claim as the Invention communicated to me by the said Ananias
Smith is,―
.i

page_text: First. The above-described method of burning the raw material from which
lime or cement is to be produced by subjecting the same to the action of heat
produced by the active combustion of liquid fuel or vapour produced therefrom,
associated or in combination with steam, whether superheated or not, and with air,
substantially as set forth.
Second. The similar method, but in which the quantity of either or all of the
said elements of combustion is controllable.
Third. The combination with a lime or cement kiln of the combustion chambers C,
air chambers E, H, fuel tank K, steam boiler L, and the pipes specified for con-
necting the combustion chambers with the boiler and fuel tank, substantially as
described and as illustrated on the accompanying Sheet of Drawings.
And, Fourth. The combination with a lime or cement kiln of the combustion
chambers C, air chambers E, H, fuel tank K, steam boiler L, superheater O, and
the means specified for connecting the boiler, superheater, and tank with the com-
bustion chambers, substantially as described and as illustrated on the accompanying
Sheet of Drawings.
In witness whereof, I, the said Bristow Hunt, have hereunto set my hand
and seal, this Twenty-seventh day of March, in the year of our Lord One
thousand eight hundred and seventy-six.