IMPROVEMENTS APPLICABLE TO KILNS AND RETORTS, SPECIALLY USEFUL IN THE MANUFACTURE OF CEMENT
Year: 1878

page_text: LETTERS PATENT to Thomas Castle, of Snodland, in the County of Kent,afor
"
the Invention of IMPROVEMENTS APPLICABLE TO KILNS AND RETORTS,
SPECIALLY USEFUL IN THE MANUFACTURE OF CEMENT."
Sealed the 22nd April 1879, and dated the 28th October 1878.
PROVISIONAL SPECIFICATION left by the said Thomas Castle at the Office
of the Commissioners of Patents on the 28th October 1878.
THOMAS CASTLE, of Snodland, in the County of Kent. "IMPROVEMENTS APPLI-
CABLE TO KILNS AND RETORTS, SPECIALLY USEFUL IN THE MANUFACTURE OF
CEMENT."
My Invention has for its object improvements in kilns and retorts, especially as
regards providing efficient ovens for the kilns or retorts, and also providing, such.
kilns and retorts with chambers for drying or baking cement, and thus utilizing the
heated products (for this purpose), which are now passed into tlie atinosphere. In
carrying out my Invention I adopt mainly the following arrangements:-The oven
or ovens are by preference formed for each retort'or kiln into two separate chambers,
the roof of such oven or ovens being formed of suitable material The said roof is
so constructed as to leave open spaces or openings, whereby the heat is allowed to
pass through said spaces or openings, which also serve to allow of the ovenvor.ovens
being charged from the top.
The chalk to be operated upon is shot by the usual opening on to the roof of said
oven or ovens; and the heat from the oven or ovens passes through the spaces or
openings in the roof, and percolates or penetrates through the mass of chalk; the
products passing off in the ordinary way,
Or the heated products can be utilized for drying or baking cement, and for this
purpose I provide a chamber situated above the level of the chalk. This chainber,
when not in use, is closed by a damper. When the drying or baking of cement-ist
required, thestop opening. of the kiln or retort is closed by at damper, and the

page_text: damper in the chamber being raised, the heated products issue into the said chamber
(which extends throughout the whole series of the retorts or kilns), and pass over
the cement, thus drying-or baking same, and thence-out.by_shaft or shafts provided
for that purpose. To place the cement in the said chamber I use trucks which
travel on rails, each of said trucks being provided with rails, on which the cement
is placed in suitable receptacles mounted on rollers, and when opposite the opening
the cement is placed in the chamber and dried, as before described.
-Each of the chambers may be closed by suitable door or doors.
Should the heat from the oven or ovens not be of sufficient power to penetrate
the mass of chalk, a gas generator or generators may be used for the purpose.
By the use of ovens, constructed-as-before described, the coal that is used becomes
converted into coke, and thus by this means great economy of fuel can be
obtained.
Should further fuel be required for the oven after once being fired, I provide for
that purpose an opening in the front of each oven, through which the fuel is
admitted, each opening being closed by a damper, to which lever and weight is
attached, but in some cases these dampers are dispensed with. The arrangement
herein-before described of drying or baking is also applicable to cement and lime
kilns of previous construction. In some cases, for drying or baking, in place of the
before-described arrangements, or in addition thereto, above the dome of each kiln
or retort, and running the whole length of such kilns or retorts, I erect a roof or
covering supported on columns, so that the cement can be baked or dried by the
heat from the kiln or retort. To facilitate combustion in the oven, pipe or pipes
(perforated) may be placed in same, communicating with the outer air, so that air
passing into the oven acts on the fuel.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas' Castle in the Great Seal Patent Office on the 28th April-
1879.
THOMAS CASTLE, of Snodland, in the County of Kent. "IMPROVEMENTS APPLI-
CABLE TO KILNS AND RETORTS, SPECIALLY USEFUL IN THE MANUFACTURE OF
CEMENT."
:
My Invention has for its object improvements in kilns and retorts, especially as
regards providing efficient ovens for the kilns or retorts, and also providing
such kilns and retorts with chambers for drying or baking cement, and thus
utilizing the heated products (for this purpose) which are now passed into the
atmosphere..
In carrying out iny Invention I adopt substantially the following arrange-
ments
The oven or ovens, furnace or furnaces, of said kilns or retorts, with or without
fire-bars, are by preference formed for each retort or kiln into two separate chambers;
the crown or roof of such oven or ovens, furnace or furnaces, being formed of
7

page_text: suitable material.
or
The said crown or roof is so constructed as to leave open spaces
or openings, whereby the heat is allowed to pass through said spaces or openings,
which also serve to allow of the oven or ovens being charged from the top. The
chalk to be operated upon is shot by the usual opening on to the crown or roof
of said oven or ovens, furnace or furnaces, and the heat from the oven
ovens, furnace or furnaces, passes through the spaces or openings in the crown
or roof, and percolates or penetrates through the mass of chalk, the products
passing off in the ordinary way. Or the heated products can be utilized for drying
or baking cement, and for this purpose I provide chamber or chambers, situated
above the level of the chalk. This chamber or chambers, when not in use, is or are
closed by a damper or dampers. When the drying or baking of cement is required,
the top opening of the kiln or retort is closed by a damper, and the damper in each
chamber being raised, the heated products issue into the said chamber which
extends throughout the whole series of the retorts or kilns), and pass over the
cement, thus drying or baking same, and thence out by shaft or shafts provided for
that purpose.
To place the cement in the said chamber I use trucks which travel on rails, each.
of said trucks being provided with rails, on which the cement is placed in suitable
receptacles mounted on rollers, and when opposite the opening the cement is placed
in the chamber and dried, as before described. Each of the chambers may be closed
by suitable door or doors. Should the heat from the oven or ovens not be of suffi-
cient power to penetrate the mass of chalk, a gas generator or generators may be
used for the purpose. By the use of ovens or furnaces constructed as before
described, the coal that is used becomes converted into coke, and thus by this means
great economy of fuel can be obtained. Should further fuel be required for the
oven or furnace after once being fired, I provide for that purpose an opening in the
front of each oven or furnace, through which the fuel is admitted, each opening
being closed by a damper, to which lever and weight is attached, but in some cases
these dampers are dispensed with. The arrangement herein-before described of
drying or baking is also applicable to cement and lime kilns of ordinary_construc-
tion. In some cases, for drying or baking, in place of the before-described arrange-
ments, or in addition thereto, above the dome of each kiln or retort, and running
the whole length of such kilns or retorts, I erect a roof or covering supported on
columns, so that the cement can be baked or dried by the heat given off from the
kiln or retort. To facilitate combustion in the oven, pipe or pipes (perforated) may
be placed in same, communicating with the outer air, so that air passing into the
oven acts on the fuel.
Having thus far described the nature of my said Invention, and incidentally.
intimated in what manner the same is to be performed or carried out in practice, I
will now proceed (aided by the accompanying Drawings) to further and particularly
describe and ascertain in what manner the same is to be performed or carried out
in practice, that is to say,—
Fig. 2, section of kiln.
Fig. 3, sectional plan, showing perforated crown or roof of furnaces or ovens. In
these Figures, A represents the kiln; A¹, top opening to kiln; B, perforated crown
or roof of oven or furnaces, which forms floor of kiln; C, ovens or furnaces; D,
fire-bars in ovens or furnaces.
F, chambers running the length of the kilns; G, damper for closing communica-
tion between chambers F and kiln A.
H, cement on rollers h on the truck I; K, roof or covering formed over the
outside of kilns; L, opening or archway for filling the kiln; M, opening for drawing
the kilns.

page_text: The chalk to be operated upon is fed in at L on to the crown or roof of the
oven, which forms the floor of the kiln. The oven or furnaces C being charged, the
heat passes-up-through-the-openings in K. percolates or penetrates through the chalk
in the kiln-A, and thence out by the opening in the top of the kiln. The heat
however can, instead of passing out-by-A¹, be diverted and utilized for drying or
baking cement. This is effected-by-closing the outlet A¹ and raising the damper G,
so that the heated products pass into the chambers F, thus drying or baking the
cement or other material H, which is brought up to the chambers by the trucks I,
and by means of the rollers / inserted in the chambers. Or the heated products
may be utilized for drying the chalk in another kiln.
This is effected by having an opening from the kilns communicating by chamber
or passage to the next or other kiln. In this case the heated-products-from one
kiln pass into and through the chalk in the next or any kiln, and are drawn through
same by pipe communicating with the chambers E, and thence to the shaft or
outlet. It is evident that when this latter arrangement is used, the chambers Fare
closed by the dampers G. When using a generator or generators, same is or are
placed in front of the kiln, and the heated products pass into the furnace or ovens
by the party wall, which is made hollow for that purpose, for assisting combustion.
Having now particularly described and ascertained the nature of the said Inven-
tion, and in what manner the same is to be performed or carried out in practice, I
hereby declare that I claim,-
First. The herein-before described combination or arrangement, constituting my
said improvements applicable to kilns and retorts, constructed and operating sub-
stantially as herein-before set forth and described.
Second. The adoption of furnace and oven arrangements, having perforated or
open work crown or roof, as adapted to kilns or retorts, substantially as herein-before
set forth and described.
Third. The use and adoption of the drying or baking chamber or chambers to
kilns used in the manufacture of cement or other material, substantially as herein-
before set forth and described, it being understood that I do not limit myself to the
exact details or configuration of the parts I have explained and shown, as same
may of course be varied or modified without essentially departing from the
Invention.
In witness whereof, I, the said Thomas Castle, have hereunto set my hand
and seal, this Twenty-sixth day of April, in the year of our Lord One thousand
eight hundred and seventy-nine.
Witness,
THO. WEEKES,
Lime & Cement Works,
-Halling,
Near Rochester,
Kent.
THOMAS CASTLE. (L.S.)