Floors for the Manufacture of Cements and Limes.
Year: 1887

page_text: Date of Application, 27th May, 1887
Complete Left, 27th Mar., 1888
Complete Accepted, 11th May, 1888
Floors for the Manufacture of Cements and Limes.
1 NATHAN ROBERT FOSTER of Cowley Uxbridge in the County of Middlesex
Contractor do hereby declare the nature of my invention for A NEW OR IMPROVED
METHOD OF CONSTRUCTING KILNS AND DRYING FLOORS FOR THE MANUFACTURE
OF CEMENTS AND LIMES, to be as follows :-
My kilns are oblong in plan with rounded angles, and with internal sides slanting
outwards. I dispense entirely with fire-bars, the air required to support combustion
rising through brickwork gratings below.
Attached to each kiln are four drying chambers in pairs, one pair over the other.
The division between each member of a pair is effected by one central wall, in
which, however, there are a number of arched openings permitting free communica-
tion between them, and giving extra floor space to the "slurry." The kilns and
upper chambers are arched over, but the kiln arch is the highest, which allows space
in the gable for a wicket for loading off the upper floors. An arch also separates the
upper from the lower chambers. The floor of the lower chambers is of fire-tiles laid
over low footings. I dry at the same time three layers of slurry-one in each of the
pairs of chambers, and one over the kiln and upper chamber arches, this last being
protected from the weather by a light galvanised iron or other roof. The two lower
layers are fed into kiln through openings opposite their respective chambers, the
openings in the bottom pair being closed during the operation of burning.
The action is as follows:-
:-
The hot air and gasses rising from the kiln pass through the loading eyes in
upper chambers, and travel to the further end, where they pass through apertures in
the floor into lower chambers, and thence back towards kiln, reaching which they are
again diverted into the channels between the footings, and so find their way, deprived
of most of their heat, to a flue leading to chimney shaft. In this manner heat
reaches each layer of slurry, except the top one, from both above and below, resulting
in a uniform drying of each layer; for the one strong heat suffices for the top, and
the fire-tiles bring the last mild heat close to the bottom layer.
DL: Och
1007

page_text: Floors for the Manufacture of Cements and Limes.
I NATHAN ROBERT FOSTER of Cowley, Uxbridge in the county of Middlesex,
Contractor, 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 for a new and improved method of constructing kilns and drying
floors for the manufacture of cements and limes, has for its objects to construct the pans
of kilns of such shape, that they shall combine a maximum capacity for the reception
of the materials to be burnt, with suitable outlets for containing the slurry to be dried;
and to construct drying chambers, so arranged that the slurry to be dried shall be of
approximately uniform depth, and that the heated gases in passing from the kiln to
the chimney shall be made to traverso the said chambers in such a manner as to pass
alternately over the surface and underneath the slurry, and thereby to effectually
utilize the heat of the said gases for the purpose of drying the slurry uniformly
preparatory to its introduction into the kiln to be burnt.
In carrying out my invention I construct the kiln pans oblong in form, as seen in
plan, and with rounded angles, and with the internal sides diverging upwards, each
kiln being completed by an arched crown, and I dispense with the low arched wickets
and high fire bars ordinarily employed, and substitute therefor wickets sufficiently
high for a man to walk through when upright, and place the fire bars or other fire
grating at a short distance above the ground Hoor. By these means the kilns can be
loaded and discharged with great ease and facility, and a powerful draught is
secured.
Attached to each kiln are drying chambers and floors arranged in pairs, each pair
being divided by means of an inner wall provided with a number of arched openings,.
which, while allowing a free passage between each pair of- chambers also increases the
drying area. Each drying chamber is covered by an arch, the upper side of which
forms the drying floor for a chamber above, except in the cases of the kiln arch and
the arches of the uppermost pair of drying chambers which form drying floors open
to the roofing cover. The floor. of the lowermost chamber is flat being composed of
tiles supported upon other tiles standing on edge, and forming a series of cellular
flues or shallow chambers leading directly to the main chimney flue. It will readily
be seen that the heated gases in passing from the kiln to the chimney traverse the
drying chambers in such manner as to pass alternately over the surface of the slurry,
and underneath the floor supporting it, and thereby drying the slurry uniformly. It
will also be seen that by constructing drying chambers in pairs instead of singly the
drying floors are less arched, and consequently the layer of slurry is more nearly
uniform in depth. Suitable openings are provided between the drying chambers

page_text: and the kiln for passing the dried slurry through when loading the kiln, and wickets
are also provided communicating with the drying chambers from the outside for the
purpose of passing in the slurry to be dried.
As the slurry dried is more than is sufficient for the supply of the main kiln, a
portion of that dried upon the arches of the upper chambers and upon the arch of
the main kiln may be utilised for the supply of an auxilliary cupola kiln.
The kiln arches are constructed higher than the arches of the top drying chambers
in order to admit of a wicket in the gable and under the centre of the main arch, to
allow of the loading of the dried slurry from the top drying floor into the kiln.
While cement is being burnt in the kiln either the top or bottom pair of drying
chambers, or both of them, may be economically employed for the purpose of
burning flare lime, the lime so produced being of very high quality.
In the accompanying three sheets of illustrative drawings Fig. 1 is a composite
elevation of a set of three kilns constructed according to my invention, and shewing
one in cross section through the drying chambers, one in front elevation, and one in
cross section through the kiln pan.
Fig. 2 is a sectional side elevation and Fig. 3 is a composite plan shewing one part
in section of a kiln through lower drying chambers, one full plan and one section
through upper drying chambers.
The kilns pans a are oblong in plan with rounded angles band with the internal
sides e diverging upwards, each kiln being completed by an arched crown d. Wickets e
permit of a man walking through when upright for the purposes of loading and
discharging the kilns, and the low fire grates f composed preferably of bricks
arranged in a cellular manner with interstices for the admission of the air complete
the lower parts of the kiln pans.
The drying chambers g h and drying floors i are arranged in pairs, each pair being
divided by the wall & provided with openings allowing a free passage between each
pair of chambers, and also with wickets n in the outer walls for admitting the slurry
to the drying chambers.
Each chamber is covered by an arch m forming on its upper side a floor for
drying the slurry. The top of the arch d of the kiln a also forms a drying floor. The
floor of the chamber his flat and composed of tiles o forming a series of cellular
flues pleading directly to the main chimney flue q.
The heated gases from the kiln pass through the chamber greturning through
chamber h and along through the cellular flues or shallow chambers p to the main
chimney flue q. it will readily be seen that in their passage through the drying
chambers the gases heat the upper surface of the slurry by direct contact and the
underside through the arches or Hoors m.
It will be obvious that the arrangement and construction of kilns or drying floors
may be modified in various ways without departing from the nature of my invention,
for example, the arch over the kiln may be placed crosswise to the chambers, or on a
line rising parallel with the chamber arches, and the kilns may be loaded or discharged
at the ends or sides according to the way in which they are placed. Besides the pair
of arches over the top chamber another pair may separate the top from the bottom
chamber; or a series of arches may be made to forun the floor of the top chamber
and a set of flues with divisions to support tiles for the flues and to carry the slurry
may be provided.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
In kilns and drying floors for the manufacture of cements and limes.
1. The construction of kiln pans of an oblong form with rounded angles, and with
internal sides diverging upwards, thereby combining a maximum capacity for the
reception of the materials to be burnt, with suitable outlets for insuring an equal
distribution of the heated gases to the drying chambers containing the slurry to be
dried substantially as described.

page_text: 2. The construction of arched chambers for drying slurry in such manner, that the
heated gases in passing from the kiln to the chimney pass alternately over the surface of
the slurry and under the arch supporting it, thereby drying the upper part by direct
contact and the under part through the arch or slurry floor, and so effectively
utilising the heat from the said gases for the purpose set forth substantially as
described.
3. The construction of kilns with drying chambers divided into pairs in a
horizontal direction to render the tops of the arches approximately flat, so as to allow
the slurry to be dried to be of approximately uniform depth substantially as
described.
4. The arrangement and construction of kilns and drying floors for the manufacture
of cements and limes substantially as described with reference to the drawings.
Dated this 27th day of March 1888
WHEATLEY & MACKENZIE,
156, Strand, W.C.,
Agents.
WHEATLEY & MACKENZIE,
156, Strand, W.C.,
Agents.