IMPROVEMENTS IN AND RELATING TO BURNING OR CALCINING LIME AND OTHER ANALOGOUS MATERIALS, AND TO THE CONSTRUCTION OF KILNS EMPLOYED THEREFOR.
Year: 1880

page_text: LETTERS PATENT to James William Raynes, and George Trevelyan Raynes, and
Peter Evans, all of the City of Liverpool, in the County of Lancaster, for an
Invention of "IMPROVEMENTS IN AND RELATING TO BURNING OR CALCINING
LIME AND OTHER ANALOGOUS MATERIALS, AND TO THE CONSTRUCTION OF
KILNS EMPLOYED THEREFOR.'
"
PROVISIONAL SPECIFICATION left by the said James William Raynes;
George Trevelyan Raynes, and Peter Evans at the Office of the Commissioners
of Patents on the 4th June 1880.
JAMES WILLIAM RAYNES, and GEORGE TREVELYAN RAYNES, and PETER EVANS,
all of the City of Liverpool, in the County of Lancaster. "IMPROVEMENTS' IN
AND RELATING TO BURNING OR CALCINING LIME AND OTHER ANALOGOUS
MATERIALS AND TO THE CONSTRUCTION OF KILNS EMPLOYED THEREFOR.'
"
Our Invention has for its object the burning or calcining of lime stone and other
analogous materials, with gaseous fuel in such a manner that the smoke and suspended
particles or products of combustion are as far as possible consumed in a combustion
chamber before the heat from the combustion of the gaseous fuel is applied to the
lime stone or other material, the result being that the calcined materials are
produced in a more pure state than by the ordinary method of applying gaseous fuel
for calcining purposes, such as the method embraced by the Patents granted to
C. W. Siemens, No. 2395, A.D. 1867, C. W. Siemens and A. Stein, No. 3457,
A.D. 1874, E. Crossland, No. 5217, A.D. 1878, in which the gaseous fuel employed
consisted of the gas generated by the combustion of coal in a producer, and the
admixture of atmospheric air. The gaseous fuel we use is the gas produced by the
burning of coal, afterwards mixed with heated atmospheric air, which is driven into
the coal gas by a jet or jets of steam passing through heated terra cotta pipes, or
heated iron pipes, or pipes of any other suitable material, either singly, or in
conjunction, depending upon the nature of the material being treated, and whether
hydrogen or oxygen, or both, are required, the admixture taking place in a
combustion chamber, and before application to the material to be calcined, and
resulting in the perfect combustion of the suspended impurities in the coal gas, and
producing a clean gaseous fuel for application in calcining the lime stone or other
material.

page_text: A kiln constructed according to our Invention, and for carrying the system
embraced by our Invention into practice, has an outward appearance somewhat
similar to an ordinary lime kiln. By preference the kiln is of a rectangular section
slightly oblong. We divide the central portion of the kiln by a wall or partition
having a tapered and pointed apex, and supported and strengthened by iron beams
covered with brick, cement, or any suitable non conducting substance to protect the
same from the action of the gas and to relieve the strain from the centre passages
on the top. This wall is carried by an arch and divides the central portion of the
kiln into two passages, and diverts the material that is fed into the kiln through the
top thereof into two streams. The bottom of the kiln is provided with draw bars
or false bottoms for allowing the calcined material to be drawn off into trucks, and
with a provision for an air blast, which can be regulated by dampers, and applied
either to the kiln direct or to the gas producer, by preference through a perforated
or grating pipe. The kiln may be classed as a running or perpetual kiln, in which
a continuous stream of material is being calcined. The gaseous fuel is admitted and
applied about twenty five feet from the bottom of, say, a sixty foot kiln through
three passages, one at each side of the kiln and one through the centre wall or
partition. The gaseous fuel issues through splayed apertures from these passages
onto the material in the kiln, namely, in jets on each side of the divided stream of
material passing through the kiln. The gas producer, which may be annexed to
the kiln, is of form similar to an ordinary producer, namely, a covered chamber
with an arched, curved, or straight roof or top, and provided with suitable furnace
bars and air inlets and fuel supply doors. Round this producer we form an air-
chamber or chambers, and between the producer and the passages leading into the
kiln we form combustion chambers, into which the air chamber or chambers open
through tapered passages. Inside the producer and in the walling thereof we
construct passages or pipes of terra cotta or fire clay, brick, or iron, for the passage
of steam. These passages or pipes open out into the passages from the air chamber
or chambers to the combustion chambers, so that steam passing through the passages
or pipes will act as an injector for driving the air which is heated in the air chamber
into the gascous fuel in the producer. The steam may be obtained from a boiler
placed over the producer and open to a portion of the heat from the producer,
sufficient to generate the pressure of steain required. The steam in its passage
through the fire clay pipes, or iron, or other suitable pipes is decomposed and
produces oxygen or hydrogen as required, the supply of which can be regulated by
suitable valves, which acting with the oxygen of the heated air, and mixing with
the stream of coal gas from the producer, causes a perfect combustion of the
suspended impurities in the coal gas, and produces a clean gaseous fuel for application
to the kiln for calcining the limestone or other contents, resulting, in the case of
lime, in the production of a clean pure lime not before obtainable by using gaseous
fuel.
By the use of our system, as before described, and by the use of a kiln and
producer constructed as described, we effect great economy in fuel, inasmuch as
perfect combustion takes place and all waste heat is utilized.
In the carrying out of our Invention the kilns may be built singly or in
groups.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James William Raynes, George Trevelyan Raynes, and Peter Evans
in the Great Seal Patent Office on the 3rd December 1880.
JAMES WILLIAM RAYNES, and GEORGE TREVELYAN RAYNES, and PETER EVANS,
all of the City of Liverpool, in the County of Lancaster. "IMPROVEMENTS IN AND
RELATING TO BURNING OR CALCINING LIME AND OTHER ANALOGOUS MATERIALS,
AND TO THE CONSTRUCTION OF KILNS EMPLOYED THEREFOR."
Our Invention has for its object the burning or calcining of lime stone and other
analogous materials with gaseous fuel in such a manner that the smoke and
suspended particles or products of combustion are as far as possible consumed in a
combustion chamber before the heat from the combustion of the gaseous fuel is
applied to the lime stone or other material, the result being that the calcined
materials are produced in a more pure state than by the ordinary method of
applying gaseous fuel for calcining purposes, such as the method embraced by the
Patents granted to C. W. Siemens, No. 2395, A.D. 1807; C. W. Siemens and
A. Stein, No. 3457, A.D. 1874; E. Crossland, No. 5217, A.D. 1878, in which the
gaseous fuel employed consisted of the gas generated by the combustion of coal in a
producer and the admixture of atmospheric air. The gaseous fuel we use is the
gas produced by the burning of coal afterwards mixed with heated atmospheric air,
which is driven into the coal gas by a jet or jets of steam or air passing through
heated terra cotta pipes, or heated iron pipes, or any other suitable material, either
singly or in conjunction, depending upon the nature of the material being treated,
and whether hydrogen or oxygen, or both, is required, the admixture taking
in a combustion chamber, and before application to the material to be calcined, and
resulting in the perfect combustion of the suspended impurities in the coal gas, and
producing a clean gaseous fuel for application in calcining the lime stone or other
material.
That our Invention may be clearly understood, we have hereto annexed a Sheet
of Drawings illustrative thereof, and marked with letters and Figures of reference
corresponding with those in the following Specification, like letters or Figures being
used to denote the same or corresponding parts throughout the various views.
Figure 1 is a sectional elevation of a kiln constructed according to our
Invention.
Figure 2 is a sectional plan at Z, Z, Figure 1.
Figure 3 is an elevation shown partly in section at Y, Y, and X, X, Figure 2,
and shown partly as a side view of Figure 1.
Figure 4 is a part sectional elevation of a modified form of Figure 1.
Figure 5 is a sectional elevation illustrating a modified form of discharging mouth
for kilns.
Upon reference it will be seen that a kiln constructed according to our Invention
and for carrying the system embraced by our Invention into practice is illustrated
at Figures 1, 2, and 3, and has an outward appearance somewhat similar to an
ordinary lime kiln. The kiln A may be of section as shown, or it may be of
rectangular or other section. The kiln is divided by the wall or partition B having
a tapered or rounded apex B'. This wall may be supported and strengthened by
iron beams covered with brick, cement, or other suitable non conducting substance
to protect the same from the action of the gas, and to relieve the strain from the
central passages on the top. The wall or partition B is carried by an arch C, and
divides the central portion of the kiln A into two passages A', A¹, and diverts the
material that is fed into the kiln through the top thereof into two streams.
bottom of the kiln is provided with draw bars or false bottoms, and may be
constructed as shown at Figure 1, or as shown in Figure 5. In the former case
The

page_text: the calcined material is discharged direct down on to trucks, which are run into
the passage or tunnel E. In the latter case the bottom A11 of the kiln is brought
down so as to have a vertical opening for the discharge. The draw bars in both
cases are indicated by the letter a and the dotted line; F, F, F, is an air passage
which may be used for supplying an air blast to the bottom of the kiln or to the
gas producer, which air blast can be regulated by dampers, and can be delivered
through a perforated pipe or grating. The kiln may be classed as a running or
perpetual kiln in which there is a continuous stream of material to be calcined.
The gaseous fuel is admitted and applied about twenty five feet from the bottom
of, say, a sixty foot kiln through the three passages H, J, J, the passage H being
built in the centre wall or partition B, and the passages J, J¹, being respectively at
the sides of the kiln. The gaseous fuel issues through the apertures e, as indicated
by the arrows, onto the material in the kiln, namely, in jets on each side of the
divided stream of material passing through the kiln; K is the gas producer which
may be annexed to the kiln. In the arrangement shown in the Drawings there are
three gas producing ovens or furnaces, the central one K and the side ones K¹, K³.
The utility of this particular arrangement of furnaces is to maintain the heat in the
kiln during the drawing off the coke or cinders; for instance, the coke in the centre
furnace K could be drawn off and at the same time the two side furnaces keep
up the necessary degrees of heat, or vice versa; also in this arrangement repairs
could be made in the producer, passages, or flues without impeding the effective
working of the kiln. The furnaces consist of covered chambers with arched, curved, or
straight roofs or tops, and are provided with suitable furnace bars Land fuel supply
doors N. Air is supplied to the furnaces through the passages P. On each side of the
producing chambers K, K¹, we form the air chambers or passages R, R, R, R.
These chambers R open into the horizontal air chamber S, which spans the top
of the producing chambers, and supplies heated air into the passage T, T, T¹, as
indicated by the arrows. The passages T, T', lead from the producers K, K¹, to
the passages H, J, J', as shown at Figure 2. Between the gas producing
chambers K, K', K, and the kiln A we construct the passages U, U', U', which also
open out into the passages T, T¹, T', as shown at Figures 1 and 2. Inside the
chamber S, and above the producer, we provide passages or pipes of terra cotta or
fire brick for the passage of steam or air. In the Drawings a system of iron pipes h
is shown, which system of piping is also led up the passages U, U¹, U. These
pipes open out into the passages from the air chamber or chambers to the
combustion chambers or passages T, T₁, T', so that steam or air passing through the
pipes will act as an injector for driving the air which is heated in the air chambers
onto the gaseous fuel from the producers. The steam may be obtained from the
boiler placed over the producer and open to a portion of the heat from the
producer sufficient to generate the pressure of steam required. The steam in its
passage through the fire clay pipes, or iron, or other suitable pipes is decomposed
and produces oxygen or hydrogen, as the case may be, the supply of which can be
regulated by suitable valves. This oxygen or hydrogen acting with the oxygen of
the heated air and mixing with the stream of coal gas from the producer causes a
perfect combustion of the suspended impurities in the coal gas, and produces a
clean gaseous fuel for application through the passages e, e, into the kiln for
calcining the limestone or other contents, resulting, in the case of lime, in the
production of a clean pure lime not before obtainable by using gaseous fuel.
In Figure 4 the gaseous fuel we use is the gas produced by the burning of coal,
afterwards mixed with heated atmospheric air by passing the air through flues or
uptakes R, R, R, R, and U, U, U, of suitable size and height. We form these
flues around or partly around the producers K, K'; the air becoming heated in
these flues by contact with the heated brickwork or lining of the producers, causes
a constant current of heated air to flow into the combustion chambers T, T¹; also
these flues or uptakes R and U effect an economy of fuel by utilizing what
would otherwise be lost from conduction or radiation around the producers K, K'.
By the use of our system, as before described, and by the use of a kiln and producer

page_text: constructed as described, we effect great economy in fuel, inasmuch as perfect
combustion takes place and all waste heat is utilized.
In the carrying out of our Invention the kilns may be built singly or in groups.
We would here state that we disclaim all matter contained in the following
Patents:-
:-
C. W. Siemens, No. 2395, A.D. 1867.
C. W. Siemens and A. Stein, No. 3457, A.D. 1874.
E. Crossland, No. 5217, A.D. 1878.
Having now described and ascertained the nature of our Invention, and explained
our new system of working lime kilns by means of gaseous fuel, and shown the
manner in which the same may be carried into practical effect, we would remark
in conclusion that we do not limit ourselves to the precise construction or
arrangement of the several parts of the kiln and apparatus as described and
illustrated, inasmuch as such parts may, as will be obvious to persons familiar with
the construction and working of lime kilns, be readily varied to meet various
requirements; what we claim as our Invention, and secured to us by Letters Patent
as aforesaid, is,―
First. Constructing and arranging kilns for burning or calcining lime with an
interior mid wall (which divides the material under treatment into two streams)
having passages or flues, through which there is applied gaseous fuel which meets
other gaseous fuel which is applied through passages in the outer walls of the
kiln, substantially as herein described and shown in the Drawings hereto annexed.
Second. Effecting the burning or calcining of lime or other analogous material
by gaseous fuel, which is applied on to both sides of a divided stream of the material
under treatment, substantially as herein described and shown in the Drawings
hereto annexed.
Third. Effecting the burning or calcining of lime or other analogous material by
gaseous fuel, the combustion of which takes place in a combustion chamber or
chambers above the gas producer or producers, substantially as herein described
and shown in the Drawings hereto annexed.
Fourth. The construction and arrangement of gas producer or producers and air
chamber or chambers, flues, or uptakes and passages, and gaseous fuel supplying
passages in connection with kilns for burning or calcining lime or analogous
materials, substantially as herein described and shown in the Drawings hereto
annexed.
Fifth. Effecting the combustion of lime and other analogous materials by a
gaseous fuel being partly coal gas generated in a producer or producers, together
with heated atmospheric air, and partly the gases resulting from the decomposition
of steam, applied substantially as herein described and shown in the Drawings
hereto annexed.
Sixth. The general arrangement and construction of kiln for burning or calcining
lime, and the producers and passages in connection therewith, substantially as
herein described and shown in the Drawings hereto annexed.
Seventh. Constructing the bottoms of what are known as running or perpetual
kilns with a side discharge, substantially as herein described and shown at Figure 5
of the Drawings hereto annexed.
In witness whereof, we, the said James William Raynes and Peter Evans,
on behalf of ourselves and the said George Trevelyan Raynes, have hereunto
set our hands and seals, this Twenty sixth day of November, in the year of
Aux Lond
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