IMPROVEMENTS for the Invention of MANUFACTURE OF CEMENT AND IN APPARATUS TO BE USED THEREIN, AND IN DRYING SEWAGE, MUD, AND SIMILAR MATTERS
Year: 1877

page_text: LETTERS PATENT to William Joy, of Snodland, near Rochester, in the County
" IMPROVEMENTS IN THE
of Kent, Cement Burner, for the Invention of
MANUFACTURE OF CEMENT AND IN APPARATUS TO BE USED THEREIN, AND IN
DRYING SEWAGE, MUD, AND SIMILAR MATTERS."
Sealed the 21st December 1877, and dated the 25th September 1877.
PROVISIONAL SPECIFICATION left by the said William Joy at the Office of
the Commissioners of Patents on the 25th September 1877.
<<
WILLIAM JOY, of Snodland, near Rochester, in the County of Kent, Cement
Burner. IMPROVEMENTS IN THE MANUFACTURE OF CEMENT AND IN APPARATUS
TO BE USED THEREIN, AND IN DRYING SEWAGE, MUD, AND SIMILAR MATTERS."
In manufacturing cement, according to the usual process, the materials are first
mixed with water, and the mixture or slurry is then run into "backs" or reservoirs,
from which after settlement the greater part of the supernatant water is drawn off
The slurry is then moved from the backs in barrows and spread on floors heated
by turnaces formed beneath them, by which means the remaining moisture is
evaporated. The dried slurry is then put into a kiln and burnt. This process
entails much labour and great expenditure of fuel.
My Invention consists, inter alia, of the improved arrangements, herein-after
described, for utilizing the waste heat of the kiln for drying the slurry to be burnt
therein, and thus effecting a saving of labour and fuel.
I form the "backs" with sloping bottoms, and I lay pipes in them, which com-
municate at one end with the interior of the backs and at the other end with an
air-tight well or with a main pipe, into which the slurry runs by gravity, or is
drawn, and from which it is removed, as herein-after described.
arrange
Over the opening by which the pipes communicate with the "backs" I
adjustable valves for regulating the passage of the slurry into and through the said
pipes.
To facilitate the removal of any obstructions in the pipes I form apertures at the
bends thereof through which instruments may be passed into the pipes, which

page_text: apertures when the slurry is passing through the pipes, are closed by caps, plugs,
or valves.
I construct the kilns as follows:-I build the body in the ordinary manner, and
provide the upper part with a damper by which the aperture therein may be closed
when necessary, and around the upper part of the kiln and on the outside thereof
I form a perforated floor or platform, which is supported at the outer part by an
annular wall built around the kiln. Below the said perforated floor I form flues, which
communicate with the interior of the kiln by other flues provided with dampers.
On to this floor the slurry is pumped from the well, herein-before described, and
spread or allowed to spread itself to the required depth, and is dried by the hot
gaseous products of combustion which pass from the body of the kiln through the
aforesaid flues, thence through the perforations in the floor and through the slurry
thereon, the said hot air and products of combustion being caused so to pass by
closing the aforesaid aperture at the upper part of the kiln, and by either forcing
air into the lower part of the said kiln or exhausting air from above the perforated
floor, which in the latter case must be provided with air-tight covers. By this
means the gaseous products of combustion aforesaid are brought into direct contact
with the slurry, which is thereby dried much more rapidly than when it is merely
spread on the surface of a heated floor as usual. I prefer to divide the flues beneath
the floors, so that the operations of charging them and drying the slurry thereon
and removing the dried slurry therefrom may be carried on successively, the
gaseous products aforesaid from the kiln being shut off from one portion of the said
Hoors, and caused to pass through other portions by means of the dampers in the
flues herein-before referred to.
The slurry when dried is removed from the floor or floors aforesaid and passed
for burning into the body of the kiln through shoots, which are closed when the
kiln is in action. Or a chamber may be formed below the floors in which the
dried slurry may be stored, if it should not be convenient to pass it direct into
the kiln.
In some cases, instead of forming drying floors around the kiln, as herein-before
described, I pump the slurry from the well or from the backs on to perforated floors
formed over furnaces through the perforations, in which floors I draw or force the
gaseous products of combustion from such furnaces. The slurry when dried is
removed to the kiln, and there burnt in the ordinary manner.
My improvements in the manufacture of cement consist further in drying and
burning the slurry at one operation. In carrying out this part of my Invention I
build a kiln with a perforated bottom, below which are furnaces or fire-places, and
I draw air through the kilns or force it into the kilns through the said furnaces or
fire-places. On the said perforated botton I run a layer of slurry mixed with fuel,
and allow it to become dry or partially dry, I then run on another layer of slurry
mixed with fuel, and when that has become sufficiently dry, another layer, and so
on until the kiln is filled. I then increase the heat in the furnace and allow the
mass of slurry and fuel to burn, and when sufficiently burnt I remove it from the
kiln and grind it to powder, as usual.
A tank may be mounted above the kiln, in which tank the slurry and the fuel
may be mixed.
In some cases I provide the chambers built around the kilns with unperforated
floors, and I so arrange the flues that the hot gaseous products of combustion shall
pass from the kiln under the said floors, thence over the slurry thereon, and thence
into the chimney of the kiln or to the open air. The chambers are in all cases
provided with openings capable of being closed, by which openings access may be
gained to the interior of the chambers when necessary.
Instead of building a single floor or platform around the kiln several floors or
platforms may be built around the kiln one above another, each being provided
with flues communicating with the kitn, through one or more of which flues the
gaseous products of combustion may be caused to pass, or from which it may be shut
off as required.

page_text: Instead of pumping the slurry direct on to the drying floors it may be pumped
into a tank formed above them, from which tank the said slurry may be run on to
the said floors.
That part of my Invention which relates to the drying of slurry by passing
5 gaseous products of combustion through it is applicable to the drying of sewage,
mud, and moist matters other than slurry.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed by
the said William Joy in the Great Seal Patent Office on the 25th March
1878.
WILLIAM JOY, of Snodland, near Rochester, in the County of Kent, Cement
Burner. "IMPROVEMENTS IN THE MANUFACTURE OF CEMENT AND IN APPARATUS
TO BE USED THEREIN AND IN DRYING SEWAGE, MUD, AND SIMILAR MATTERS."
In manufacturing cement, according to the usual process the materials are first
inixed with water, and the mixture or slurry is then run into " backs" or reservoirs,
from which after settlement the greater part of the supernatant water is drawn off.
The slurry is then removed from the backs in barrows, and spread on floors heated
by furnaces formed beneath then, by which means the remaining moisture is
evaporated. The dried slurry is then put into a kiln and burnt. This process entails
much labour and great expenditure of fuel.
My Invention consists, inter alia, of the improved arrangements herein-after
described for utilizing the waste heat of the kiln for drying the slurry to be burnt
therein, and thus effecting a saving of labour and fuel.
I form the backs with sloping bottoms, and I lay in them pipes which communi-
cate at one end with the interior of the backs, and at the other end with an air-
tight well, or with a main pipe, or with a tank or reservoir, into which the slurry
runs by gravity, or is drawn, and from which it is removed as herein-after
described.
Over the openings, by which the pipes communicate with the backs, I arrange
adjustable valves for regulating the passage of the slurry into and through the said
pipes.
To facilitate the removal of any obstructions in the pipes I form apertures at the
bends thereof, through which instruments may be passed into the pipes, which
apertures when the slurry is passing through the pipes are closed by caps, plugs, or
valves; or the said pipes may be cleared of obstructions by forcing water into
them.
Figure 1 of the accompanying Drawings is a plan of a "back" constructed
according to my Invention, the pipes of which cominunicate with an air-tight well;
Figure 2 is a longitudinal section of the same, taken on the line 1; Figure 1 and
Figure 3 is a transverse section of the same, taken on the line 2, Figure 1.
The same letters and figures of reference indicate like parts on these and in the
other Figures of the Drawings.
A, A, are the walls of the "back," in which walls sluiceways a¹, a², closed by
boards a², a², are formed as usual; B, B, are the pipes laid in the bottom of the
back," which communicate at 61 with the well C, which is closed by an air-tight

page_text: cover c¹ provided with a cock c²; 62, 62 are openings formed in the pipes B, B,
through which openings the slurry enters the said pipes, as herein-after described;
D, D, are valves carried by screwed rods d', ', provided with handles d³, d², by
means of which the said openings 62, 62, may be closed when necessary; E, E, are
roofs or covers of wood or metal supported by posts e', e¹, and erected over the
mouths or openings 62, 62, in the pipes B, B, to prevent the direct downward flow of
slurry into the pipes; F, F, are banks of earth thrown up around and sloping
towards the said openings, the inclined surfaces of which banks directs the slurry
towards and together with the inclined roofs or covers E, E, cause it to be drawn
from a large area around the mouths 62, 63, of the pipes B, B; d³, d³, are platforms
or stages erected on posts d, d'; and d³, d, are planks by which access may be
gained to the handles d², d², of the valve rods d', d¹, when it is required to work
the valves; c³ is a pipe leading from the well C to a pump (not shown), by which
the slurry passing into the well is drawn therefrom as herein-after described.
The object of the well C is to admit of slurry from several "backs" being
withdrawn by the same pump, and although I prefer this arrangement the same
effect may be obtained by connecting the pipes from several backs to one main pipe
communicating with the pump. When only one " back is used I connect the
pipes therein directly with the pump.
(6
This apparatus is used and acts as follows:-When the slurry is to be drawn off
from the back," the valve nearest to one of the sluiceways a', a', is opened, and
the pump is worked; the air being thus withdrawn from the well C the slurry
from above the open pipe passes through it, and so enters the said well, whence it
passes through the pipe c³ to the pump, and is thence directed by pipes to drying
floors or elsewhere, as may be desired. When the slurry over the open valve is
thus lowered the supernatant water flows into the depression in the surface of the
slurry at that part, and may be allowed to run off by opening the adjacent sluice-
way. The valve may then be closed, and another valve, or several valves may be
opened, the slurry being thus drawn from any desired part of the "back" until it is
empty, the inclined surfaces of the banks F, F, causing the slurry to flow to the
mouths b', 62, of the pipes B, B. While the slurry is being drawn through the
pipes B, B, and when the back is nearly emptied, it is advantageous to stir the
slurry occasionally with a "lute."
In order that the slurry may not become too thick to flow freely through the
pipes it should be tested from time to time, and when found to be of the required
consistency it should be drawn off as soon as convenient. By the use of this
apparatus time and labour are economised, the slurry being forced to pass from
any required part of the "backs" by simply raising the valve in the pipe at that
part.
The "backs" are also emptied much more quickly than by the usual process of
removing the slurry in barrows, and the delay which is usually caused by wet
weather is avoided, owing to the slurry being by my process drawn from the lower
part of the "back," where the said slurry unaffected by rain, and the process of
emptying the "backs" may be begun much sooner.
"
The thinnest slurry near the surface may be left in the "back" for the next charge
to be added to, instead of being either allowed to run off with the supernatant water, or
of being kept with the rest of the slurry undisturbed in the back" for a longer
period to allow of further settlement. For this reason a smaller number of "backs "
suffice for the manufacture of a given quantity of cement in a given time by my
process than by the ordinary process.
The plant required in carrying out my process being subject to less wear and
tear than that required for the ordinary process, is less expensive in maintenance.
Figure 4 of the accompanying Drawings is a transverse section of a "back,"
showing the arrangement of the pipes when it is preferred to allow the slurry to
flow from the "back" by gravity; G is the tank with which the pipes communicate,
and into which the slurry flows when the valves are raised, and whence it may be
removed by a chain pump, or by chains and buckets, or by other suitable means to

page_text: the drying floors or chambers. In this, and in other Figures of the Drawings
where parts are illustrated, which have been described with reference to other
Figures, I do not think it necessary to repeat the description of such parts.
Figure 5 is a plan of a back showing another arrangement of pipes. In this
arrangement the ends of the branches of the pipe Bare turned up, and communi-
cate with similar pipes ba, b, arranged radially, the ends 64, 64, of which smaller
pipes are open, and are also turned up. In each of the branches of the pipe B, and
near their junction with it, are sluice valves 65, 1, by which the communication of
the small pipes 63, 63, with the said pipe B may be cut off when required. The pipe
B in this case is or may be provided with openings 62, 62, which are covered by
valves (not shown as in the arrangements herein-before described and illustrated in
Figures 1, 2, 3, and 4. Figure 6 is an elevation of part of one of the branches
of the pipe B, showing the arrangement of the sluice valve and the radiating
pipes b³, b.
I construct the kilns as follows:-I build the body in the ordinary manner, and
provide the upper part with a damper, by which the aperture therein may be
closed when necessary; and around the kiln and on the outside thereof I form floors,
on which the slurry to be dried is spread, which floors are supported at the outer
part by an annular wall built around the kiln. Below the said floors I form flues,
which communicate with the interior of the kiln and with a chimney,or with the open
air by other flues provided with dampers, so arranged that the hot gaseous products
of combustion may be caused to pass from the kiln under the said floors, thence over
the slurry thereon, and thence into a chimney or to the open air. The chambers are
in all cases provided with openings capable of being closed, by which openings
access may be gained to the interior of the chambers when necessary.
The slurry when dried is removed from the drying floors aforesaid, and passed for
burning into the body of the kiln through apertures which are closed when the
kiln is in action; or a chamber may be formed below the floors in which the dried
slurry may be stored if it should not be convenient to pass it direct into the kiln,
and instead of pumping the slurry direct on to the drying floors it may be pumped
into a tank formed above then, from which tank the said slurry may be run on to
the said floors.
This arrangement is illustrated in Figures 7, 8, and 9 of the accompanying
Drawings, Figure 7 being a vertical section taken on the line 3, Figure 8 (which
is a horizontal section taken on the line 4, Figure 7), and Figure 9 a vertical
section taken on the line 5, Figure 8. H is the body of the kiln, which is provided
with a damper (not shown) at the upper part; h' is the annular wall built around
the kiln, and I, I, are the drying floors, which are supported at the outer and inner
sides by the walls of the kiln and the annular wall h³ respectively, and are sup-
ported from beneath by circular walls 2, 2, built on floors j', 2, which are supported
by arches, the spaces between the said floors I and j', and I' and j³, forming flues
J, J', which communicate with the interior of the kiln H by short flues 2, h³,
provided with dampers 3, 4, to which are attached chains 7, 75, which pass through
openings in the floors above them, by which means the said dampers may be
worked from the outside of the kiln. K is the tank formed on the top of the kiln
by building a floor on arches above the upper floor I, the wall k², and the upper
part of the wall forming the sides of the said tank. k³, k³, are ball valves, which
close shoots k', k, by which, when the said valves are removed, the contents of the
tank K pass on to the floor I. the space between the floors I and ¹, and the space
between the floors I¹ and ¹ forin chambers L, L¹. L' is another chamber forined
below the chamber L', in which chamber L² the dried slurry may be stored.
If it be found necessary, a furnace communicating with the flues J and J' may be
built in the chamber L2, by the heat from which furnace slurry may be dried on the
floors I and I, when the kiln is out of action. Or the heat from the said furnace
may be used to supplement the heat passing through the said flues from the
kiln when it is in action; M is the chimney, with which the said chambers L, L';
communicate by means of short flues m', m², provided with dampers m³, m², m³, m²;

page_text: 11, 12, are walls built across the chambers L, L', and flues J, J'; h4, ho, are openings
formed in the floors I, I, which openings form communications between the flues
J, J, and the chambers L, L', respectively; h6, 7, are openings formed in the wall
h¹, capable of being closed by doors or shutters (not shown); and he, he, are openings
in the wall of the kiln, which form communications between it and the chambers
L, L, L2, which openings ha, ha, are bricked up when the kiln is charged ready for
firing, 2, are short shafts built between the floors I,, and I,j³, and covered by
plates, 3, through which shafts the slurry may, if desired, be passed down from
one chamber to another; is a brick casing or shaft built between the floors l¹ and
; and j is a fire-clay tube placed between the floors ¹ and I, and is a small
chamber forined within the chamber L, of sufficient size to allow of the damper ja
and chains jo, jb, working freely, which shaft tube and chamber preserve the chains
and the dampers from the direct action of the heat passing from the kiln.
The method of using and the action of this apparatus are as follows:-The kiln
is filled with dried slurry and fuel in the usual way, the openings h³, h³, being
bricked up as the kiln is filled. The charge is then fired, and the gaseous products
of combustion are for a time allowed to pass off in the usual way, the damper at
the top of the kiln being left open. The slurry to be dried is pumped from the
air-tight well, or from the tank G, or is otherwise raised into the tank K, and is
thence allowed to run through the openings, le, on to the drying floor I. When
a sufficiently thick layer of slurry has accumulated on the said floor the openings
h, k, and ho, ho, are closed. The dampers j³ and m³ are then opened, and the
damper at the top of the kiln is closed, by which means the gaseous products
of combustion from the kiln are caused to pass up the flue h into the flues J, J,
beneath the floor I, through which flues they pass until they meet the wall /, when
they pass up through the opening and pass back over the said floor through the
flue m' into the chimney M, and thence into the open air. The course of the gases
as thus described is indicated in the Drawings by double-headed arrows. Both the
upper and under surfaces of the slurry on the floor I are thus subjected to the action
of the hot gases passing from the kiln, the steam from the slurry being rapidly
taken up and carried away by the said gases as they pass over it. When it is
desirable to prevent the passage of the gases over the slurry the damper m² is
opened. The said gases then pass from the flues J, J, through the flue m² into the
chimney, instead of passing through the chamber L and into the chimney by the
flue m'. The course of the gases as thus described is indicated in the Drawings by
single-headed arrows.
When the layer of slurry on the floor I is dried the damper at the top of the
kiln and the doors of the openings he, ho are opened, and the dampers j and m³
are closed. The slurry is then. when sufficiently cool, removed from the said floor
and passed through the shafts 12, 12, into one or other of the chambers below. The
said shafts are then again covered and more wet slurry is run on to the floor to be
dried. I prefer to run only a thin layer of slurry on to the floors at a time, it being
then, when dried, in a very convenient forın for burning in the kiln; but sufficient
slurry to load the kiln may be run on to the floor at once, and dried during the
burning of one charge in the kiln. The charge in the kiln, when burnt, is drawn
therefrom in the ordinary manner.
Both the drying floors I and I' may be loaded at the same time with wet slurry
to be dried by the heat from the kiln, the damper j' in the flue ha leading to the
flues J, J, under the drying floor I', and the dampers m³ and m in the flues m', m²,
leading from the chamber L' to the chimney M, being operated as described with
respect to the dampers j³, m³, m, in the corresponding flues in connection with the
Alcor I and chamber L. When both floors are thus loaded I prefer to allow the
gases from the kiln first to pass through the flues J, J, under the floor I, and when
the slurry thereon is dried I shut the gases off from the said flues; and by opening
the dampers and m I cause them to pass through the flues J₁, J, and the
chamber L', thereby drying the slurry on that floor.
Instead of causing the products of combustion to pass from the flues m¹, m², m³ m³,

page_text: into a chimney built specially for them they may be carried by flues to the chimney
of an adjacent kiln. Light stagings or scaffolds may be built outside the wall h' to
give easy access to the dampers m³, m², m³, me, and openings h, he, h, h. By thus
effecting the drying of slurry by heat from the kiln, which would otherwise be
allowed to pass away unutilised, the expense of the fuel used in the furnaces under
the drying floors on which the slurry is usually dried is saved, and the labour of
removing the dried slurry from the said floors to the kilns is greatly reduced, the
slurry, when dried in chambers around the kiln, having merely to be passed into it
from the said chambers.
By passing the gaseous products of combustion first under the floors on which
the slurry lies, and then over the slurry on the floors, the heat is utilized to a
greater extent then when it is simply passed under the said floors or over the
slurry.
In some cases instead of forming drying floors around the kiln, as herein-before
described, I pump or otherwise remove the slurry from the well C, or from the
"backs," or from the tank G, and spread it on perforated floors formed over furnaces,
through the perforations in which floors I draw or force the gaseous products of
combustion from such furnaces. The slurry, when dried, is removed to the kiln and
there burnt in the ordinary manner. By this means the gaseous products of
combustion aforesaid are brought into direct contact with the slurry, which is
thereby dried much more rapidly than when it is merely spread on the surface of a
heated floor as usual. This part of my Invention is applicable to the drying of
sewage, mud, and other moist matters.
My Invention consists further of improvements in drying and burning slurry at
one operation. In carrying out this part of my Invention I build a kiln with a
perforated bottom, below which is a furnace or fire-place, and I force air through
the said kiln, or through the said furnace or fire-place into and through the kiln.
On the said perforated bottom I run a layer of slurry mixed with fuel, and allow it
to become dry or partially dry; I then run on another layer of slurry mixed with
fuel, and when that has become sufficiently dry another layer, and so on, until the
kiln is filled. I then increase the heat in the furnace and allow the mass of slurry
and fuel to burn, and when sufficiently dry I remove it from the kiln and grind it
to powder as usual.
Figure 10 of the accompanying Drawings is a vortical section taken on the line 6,
Figure 11; and Figure 11 is a horizontal section, taken on the line 7, Figure 10, of
a kiln constructed according to this part of my Invention.
Figures 10, 12, and 12", represent details herein-after referred to. N,N, are the
walls of the kiln, in which walls are formed openings n', n², n³, n', to admit of
access to the interior to the kiln, which said openings, when the kiln is in action,
are closed, as herein-after described. O is the bottom or floor of the kiln, which
floor is formed of slabs of fire-clay perforated at o¹, o¹, the said slabs being supported
partly by the side walls of the kiln, into which they are recessed, and partly by
arches o, o, built over the crown pl of the furnace P. p², p², are holes formed in
the crown of the furnace, through which the heat passes to the perforated floor O.
Q is a pipe having branch pipes q', q², provided with cocks 7³, qt. The pipe q',
which is closed at the end, is carried partly round the furnace in the space between
it and the wall N of the kiln, and is perforated at that part so as to allow the air
to pass from it in a number of snail streams, by which means the air issuing from
it is evenly diffused through the space beneath the floor O. The pipe Q is connected
with a blowing apparatus (not shown), by which cold or hot air is forced either
direct into the kiln through the pipe ql, or through the pipe q, into and through
the furnace, and thence into the kiln. m is the mouth of the furnace, which is
provided with doors (not shown), by which access of air to the fire, except through
the pipe is prevented. ", n, are piers which support a tank R provided with a
valve, into which tank the slurry is pumped, and from which it is allowed to
flow into the kilu through a suitable shoot or hose (not shown), as required. S is a

page_text: screwed shaft (preferably hollow). s, s¹, 82, are beams which rest in recesses formed
in the sides of the kiln.
The shaft S works in bearings 8, 83, affixed to the said beams, and arranged in a
manner similar to that herein-after described, and illustrated with reference to
Figures 12 and 12". 84 is a screw box supported by the beam st, in which bearings
and screw box the shaft S works. 65 is a blade or leveller screwed to the lower
end of the shaft S, as shown separately in sectional plan and elevation drawn to a
larger scale in Figures 12 and 11, the spreader being bound to the shaft S by a
metal straps, which is hinged to a plate 8' bolted to the spreader s', and is pre-
vented from becoming disengaged therefrom by a catch s jointed at & to the free
end of the said strap, the hooked end of which catch engages with the upper part of
the spreader, which, when the kiln is being filled, is caused to rotate by means of a
driving belt or rope so, which passes around the shaft S (as shown separately on a
larger scale in Figure 10) and over a driving pulley driven by a steam engine or
other suitable motor.
at
The method of using and the action of this apparatus are as follows:-The
opening n is bricked up, and the slurry to be dried and burnt is drawn from the
back by the pump, which communicates with the pipe, or from the tank G
(see Figures 1 and 4), and is forced or raised into the tank R. The fire is then
lighted in the furnace P, and the furnace doors are closed, and air is forced into it
through the pipe q*, the ccck q* being open and the cock closed. The valve
the bottom of the tank R is then opened, and the slurry flowing therefrom is con-
ducted into the kiln N by means of a shoot placed under the said valve and passing
through the aperture n¹. While the slurry is passing into the kiln the shaft S is put
in motion, the leveller s spreading and levelling the slurry on the floor O, the screw
on the shaft S causing it to rise as it revolves, thereby keeping the blades about on
a level with the surface of the slurry.
When a sufficient quantity of slurry has been run on to the floor O the valve r' is
closed, and the said slurry is dried or partially dried by the hot air and volatile
products of combustion from the furnace P, which pass through the perforations
o, o¹, in the floor O, and force their way through the slurry thereon, in which as it
dries passages are thus formed through which the hot gases pass to and through the
next layer of slurry, which is run on as soon as the first layer has become sufficiently
dried.
The slurry may be mixed with the fuel either in the tank R, or the slurry and
fuel may be passed separately into the kiln and there mixed or allowed to mix.
The perforated floor O may be covered with fuel before running the slurry into
the kiln.
When the slurry has risen in the kiln to nearly the level of the beam 82, it is dis-
connected from the screwed shaft S by raising the catch and turning the outer
plate of the bearing on its hinge, and is removed from the kiln, and the aperture n³
is then bricked up. Successive layers of slurry are then run into the kiln and dried
until the slurry is nearly on a level with the beam s', when the leveller is discon-
nected from the shaft S, and the said shaft and the beans 8, 81, are removed from
the kiln, and the apertures n¹, n², are bricked up. The heat in the furnace P is then
increased until the fuel in the lower part of the mass of dried slurry and fuel
becomes ignited, when the fire in the furnace may be allowed to die out, the supply
of air to the kiln being continued until the whole of the fuel mixed with the slurry
is burnt and the dried slurry is calcined. The kiln is then opened by removing the
brickwork from the bricked up openings n', n², n³, nt, and the calcined mass is
removed and ground to powder as usual.
The advantages attending the use of this process and apparatus are that the hot
gases being caused to pass through and in direct contact with the slurry, it is dried
imore rapidly that when exposed to surface heat only; and the slurry being both
dried and burnt in the kiln, the expense of removing the dried slurry from drying
floors and charging it into the kiln as is now usual is saved.

page_text: Having thus described the nature of my Invention, and the manner in which the
same is to be performed, I wish it to be understood that I make no claim to the
principle of puinping slurry from the "backs" on to drying floors instead of barrowing
it; neither do I claim the principle of drying slurry by waste heat previously to
burning it; neither do I limit nyself to the precise details herein-before described,
as they may be varied without departing from the nature of my said Invention; but
I claim as my said Invention,-
Firstly. The general construction and arrangement of the apparatus, herein-before
described and illustrated in Figures 1, 2, 3, 4, and 5 of the accompanying Drawings,
for containing and collecting the slurry and transferring it to the apparatus by which
it is to be dried, that is to say, arranging in a "back" or "backs" a pipe or pipes
provided with valves and connected to a pump, so that the slurry may be drawn
through the said pipe or pipes from any desired part or parts of the said "back" or
"backs," essentially as and for the purposes described.
Secondly. The improvements, herein-before described with reference to Figures 7,
8, and 9 of the accompanying Drawings, in the construction of cement kilns, that is
to say, constructing around the kiln a chamber or chambers connected with the body
of the kiln by flues so arranged that the gaseous products of combustion from the
said kiln may be caused to pass through the said flues and chambers so as to dry the
slurry therein.
Thirdly. The improvements, herein-before described and illustrated in Figures 7,
8, and 9 of the accompanying Drawings, in the construction of cement kilns, that is
to say, constructing in connection with drying chambers formed around such kilns
flues provided with dampers, and so arranged that the gaseous products of combus-
tion may be caused to pass from the kiln under the Hoors of the said chambers,
thence over such, floors, and thence out of the said chambers into a chimney.
Fourthly. Combining with the apparatus, herein-before described with reference
to Figures 1, 2, 3, 4, and 5 of the accompanying Drawings, the improved cement
kiln, herein-before described, and illustrated in Figures 7, 8, and 9 of the said
Drawings.
Fifthly. The drying of slurry and sewage mud and similar matters upon a per-
forated Hoor by forcing or drawing the gaseous products of combustion froin a
furnace through the perforations in the said floor and through the said slurry or
sewage mud or other matters, essenntially as herein-before described.
Sixthly. The improved apparatus, herein-before described and illustrated in
Figures 10 and 11 of the accompanying Drawings, for drying and burning slurry at
one operation, that is to say, a kiln having a perforated false bottom and provided
with means for forcing air through the furnace, through the perforations in the said
false bottom, and through the charge of fuel and slurry tuereon, essentially as and
for the purposes described.
In witness whereof, I, the said William Joy, have hereunto set my hand and
seal, this Twenty-first day of March, in the year of our Lord One thousand
eight hundred and seventy-eight.
5 Witness,
H. H. MURDOCH,
Staple Inn,
London.
WILLIAM JOY. (L.S.)