IMPROVEMENTS IN APPARATUS FOR DRYING, ROASTING, HEATING, OR COOLING SUBSTANCES IN PIECES OR IN A GRANULAR, POWDERED, SEMI- FLUID, OR SUCH LIKE STATE
Year: 1881

page_text: LETTERS PATENT to John Clayton Mewburn, of 169, Fleet Street, in the City
of London, Patent Agent and Consulting Engineer, for an Invention of
"IMPROVEMENTS IN APPARATUS FOR DRYING, ROASTING, HEATING, OR
COOLING SUBSTANCES IN PIECES OR IN A GRANULAR, POWDERED, SEMI-
FLUID, OR SUCH LIKE STATE" A communication from abroad by Franz
Stroehmer, Engineer, and William Henry Eales, Merchant, both of Dresden,"
Saxony
PROVISIONAL SPECIFICATION left by the said John Clayton Mewburn at
the Office of the Commissioners of Patents on the 25th June 1881.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent.
Agent and Consulting Engineer. "IMPROVEMENTS IN APPARATUS FOR DRYING,
ROASTING, HEATING, OR COOLING SUBSTANCES IN PIECES OR IN A GRANULAR,
POWDERED, SEMI-FLUID, OR SUCH LIKE STATE" [A communication from abroad
by Franz Stroehmer, Engineer, and William Henry Eales, Merchant, both of
Dresden, Saxony.]
The improvements relate to apparatus in which the material to be treated moves
or travels downwards from one to another of a series of horizontal smooth floors or
stages, and falls alternately at the periphery and at the centre part of such floors,
whereby the material to be treated is subjected to the direct action of a heating or
cooling apparatus. In the following Specification I will mainly refer to the action
of a heating apparatus; but it is obvious that if instead of hot water or steam a
cooling agent is used the action will be reverse of that effected by using a heating
agent.
The improved apparatus mainly consists of a vertical cylinder, in the middle of
which a vertical shaft is caused to rotate by gearing outside the cylinder. The
cylinder is divided into flat floors or stages, on the upper surfaces of which arms
revolve which are fixed to the vertical shaft. These arms are provided, according
to the quality of the material under treatment, either with scrapers or brushes or
such like devices, which cause the material to move on the one stage from the

page_text: periphery to the central opening, whereas on the next or alternate stage they move
the material from the centre to an opening between the periphery of said stage
and the inner wall of the cylinder. This system is alternately continued from top
to bottom of the cylinder. The material is supplied by a pipe at the top and
leaves the cylinder at the bottom by another pipe or shoot, and is discharged into
a box or receptacle in such manner that no air is admitted from underneath into
the cylinder. The cylinder is mounted on columns and is closed at bottom; at the
upper part a funnel or chimney carries off the air, the admission of which into the
cylinder is regulated by slides in the lower part of the walls of the cylinder. If
the material is to be roasted or dried the cylinder is provided at or about its
middle portion between several of the stages with one or more coils of pipes
constituting the heating apparatus. The coils of pipes in the different stages may
be connected with each other, so that the lower coil communicates with the inlet
pipe for steam or hot water and the upper coil communicates with the blast or
outlet pipe, or the coil of each stage may separately communicate with the inlet
and outlet pipes; this latter arrangement is preferable in cases where the material
under treatment is difficult to dry or requires a high degree of roasting. It is
preferred to make the distance between the stages where the heating apparatus is
inserted somewhat larger than the distance between the other stages. The heat
will mainly be imparted direct to the stages and material in the vicinity of the
drying or heating apparatus. The upper stages and the material upon the same
will receive a preliminary heating by the ascending air, whereas the heating
material falling on the stages in the lower portion of the cylinder will impart the
heat to the cool ascending air which is admitted by the slides. In this manner the
heat of the apparatus is perfectly utilized and the material will reach the receiving
box in the required roasted or dried state. In thus arranging the heating
apparatus I attain the advantage that the material under treatment will reach the
said box in a cool condition, which is highly desirable in many instances.
In cases where the material is very difficult to treat in regard to drying, the
coils of pipes may be replaced by a system of parallel pipes in each of the stages in
the middle portion of the cylinder.
If the material is intended to leave the cylinder in a heated condition, that is,
not previously cooled by ascending air, which may be desirable, for example, with
small coals mixed with pitch or such like substance for the manufacture of
briquettes or blocks, the heating apparatus is arranged in the lower stage or
portion of the cylinder, so that the main heat is imparted to the material at or
near the outlet of the material from the cylinder. If the apparatus is intended
for cooling purposes the last mentioned arrangement of placing the pipe coils in the
lower stages is to be preferred.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Clayton Mewburn in the Great Seal Patent Office on the
24th December 1881.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVEMENTS IN APPARATUS FOR DRYING,
ROASTING, HEATING, OR COOLING SUBSTANCES IN PIECES OR IN A GRANULAR,
POWDERED, SEMI-FLUID, OR SUCH LIKE STATE." (A communication from abroad
by Franz Stroehmer, Engineer, and William Henry Eales, Merchant, both of
Dresden, Saxony.)
The improvements relate to apparatus in which the material to be treated moves
or travels downwards from one to another of a series of horizontal smooth floors
or stages, and falls alternately at the periphery and at the centre part of such floors,
whereby the material to be treated is subjected to the direct action of a heating
or cooling apparatus. In the following Specification I will mainly refer to the
action of a heating apparatus; but it is obvious that if instead of hot water or
steam a cooling agent is used, the action will be the reverse of that effected by
using a heating agent.
Figure 1 of the accompanying Drawings is a vertical section of the apparatus
which mainly consists of a vertical cylinder a, in the middle of which a shaft dis
caused to rotate by gearing x, x, driven from outside the cylinder. The cylinder
is divided into flat floors or stages, on the upper surfaces of which arms revolve,
which are fixed to the vertical shaft d. These arms are provided, according to the
quality of the material under treatment, with scrapers, or brushes, or such like
devices which cause the material to move on the one stage from the periphery to
the central opening (see scrapers g to g5, Figure 2), whereas on the next or
alternate stage they move the material from the centre to an opening between the
periphery of said stage and the inner wall of the cylinder (see scrapers ' to h
Figure 3). This system is alternately continued from top to bottom of the
cylinder. The material is supplied by the pipe i at the top, and leaves the cylinder
at the bottom by the pipe or shoot and is discharged into a box or receptacle in
such manner that no air is admitted from underneath into the cylinder. The
cylinder is supported on columns 7 and is closed at bottom; at the upper part the
funnel or chimney n carries off the air, the admission of which into the cylinder is
regulated by the slides m in the lower part of the walls of the cylinder. If the
material is to be roasted or dried the cylinder is provided at or about its middle
between several of the stages with one or more serpentine pipes o, o, o, Figure 1,
constituting the heating apparatus. The coils of pipes in the different stages may
be connected with each other, so that the lower coil communicates with the inlet pipe
for steam or hot water, and the upper coil communicates with the blast or outlet
pipe (Figure 4) or the coil of each stage may separately communicate with the
inlet and outlet pipes (Figure 5); this latter device is preferable in cases where the
material under treatment is difficult to dry or require a high degree of roasting.
It is preferred to make the distance between the stages where the heating appa-
ratus is inserted somewhat larger than the distance between the other stages when
the heating apparatus is in the form shewn in Figure 1. The heat will mainly be
imparted direct to the stages and material in the vicinity of the drying or heating
apparatus. The upper stages and the material upon the same will receive a
preliminary heating by the ascending air, while the heated material falling on the
stages in the lower portion of the cylinder will impart the heat to the cool
ascending air, which is admitted by the slides m. In this manner the heat of the

page_text: apparatus is perfectly utilized and the material will reach the receiving box in the
required roasted or dried state. In thus arranging the heating apparatus I attain
the advantage that the material under treatment will reach the said box in a
cooled condition, which is highly desirable in many instances. In cases where the
material is very difficult to treat in regard to drying, the coils of pipes may be
replaced by a system of parallel pipes in each of the stages in the middle portion
of the cylinder.
If the material is intended to leave the cylinder in a heated condition, that is,
not previously cooled by ascending air which may be desirable, for example, with
small coals mixed with pitch or such like substance for the manufacture of
briquettes or blocks, the heating apparatus is arranged in the lower stage or portion
of the cylinder so that the main heat is imparted to the material at or near the
outlet of the material from the cylinder.
If the apparatus is intended for cooling purposes the last mentioned arrangement,
that is to say, placing the pipe coils in the lower stages, is to be preferred.
Instead of using the arrangement of coiled pipes a between the flat floors or
stages, as illustrated in Figure 1, it is sometimes preferred to use the body of the
floor itself as the heating part, as illustrated in Figures 4 and 5. In Figure 4 the
floors are made hollow so as to allow steam or hot water to enter them. In this
case the body of the floors or stages must be made capable of withstanding the
high pressure of the steam employed. In Figure 5 the floors are made of cast
metal, and partly hollow, the hollow space being in the form of spiral pipes so as
to allow steam or hot water to be introduced to one part of said floor, and after
having circulated in the spiral coil of pipes to leave the floor at another end.. In
Figures 4 and 5 I have shown two different systems of applying steam or hot
water. In Figure 4 the same is introduced at the lower floor, as indicated by the
arrow, and rises through all the upper floors until it leaves the apparatus, as
indicated. In Figure 5 the hot water is introduced separately into and leaves each
floor. Either of these methods of applying the steam or water may be used in
connection with the coiled pipes, Figure 1, or with the hollow floors, Figure 4, or
with coiled spiral pipes forming the hollow space of such floors, Figure 5. In
using the hollow floors (Figure 4) or spiral coils in the hollow floors (Figure 5)
the floors may be arranged nearer to each other than in the arrangement shewn
in Figure 1, so that the lower surface of the upper floor acts by radiant heat upon
the material under treatment on the lower floor, and by thus placing the floors
nearer together the number of floors within an apparatus of given height may be
increased.
Having now described the nature of the said Invention, as communicated to me,
and in what manner the same is to be performned, I declare that I claim as the
Improvements in Apparatus for Drying, Roasting, Heating, or Cooling Substances
in Pieces, or in a Granular, Powdered, Semi-fluid, or such like State,”-
«
First. In an apparatus in which the material under treatment moves or travels
downwards from one to another of a series of stages or floors within a cylinder,
and falls alternately at the periphery and at the centre, the employment of a
system of pipes, through which a heating medium circulates, these pipes being
arranged between those floors which are situated at or about the middle of the
cylinder, so that the main heating of the material takes place in the middle stages,
while in the upper stages the material receives a preliminary heating, and in the
lower stages it is cooled by imparting heat to the ascending air admitted from
below, all substantially as hereinbefore described and represented in Figures 1, 2,
and 3.
Second. In an apparatus of the kind referred to the employment of a system of
pipes, through which a heating or cooling medium circulates, these pipes being
arranged between the floors or stages of the lower portion of the cylinder, so that
the main heating or cooling of the material takes place in this lower part, and the
material issues from the apparatus in a hot or cool state (as the case may be),
while the preliminary heating or cooling takes place in the upper part of the

page_text: apparatus only, substantially as hereinbefore described with reference to Figures 1,
2, and 3.
Third. The modified arrangements of the apparatus, substantially as represented
in Figures 4 and 5 respectively, and hereinbefore described.
In witness whereof, I, the said John Clayton Mewburn, have hereunto set
my hand and seal, this Twenty third day of December, One thousand
eight hundred and eighty one.
J. C. MEWBURN. (L.S.)