IMPROVEMENTS IN THE METHOD OF AND APPARATUS FOR DRYING OR DRYING AND COOLING SUGAR AND OTHER SUBSTANCES
Year: 1883

page_text: LETTERS PATENT to Charles Aubrey Day, of 321, High Holborn, in the
County of Middlesex, Fellow of the Institute of Patent Agents for an
Invention of "IMPROVEMENTS IN THE METHOD OF AND APPARATUS FOR DRYING
OR DRYING AND COOLING SUGAR AND OTHER SUBSTANCES communicated to
him from abroad by George Morgan Newhall, of Philadelphia, Pennsylvania,
in the United States of America
"
PROVISIONAL SPECIFICATION left by the said Charles Aubrey Day at
the Office of the Commissioners of Patents on the 3rd October 1883.
CHARLES AUBREY DAY, of 321, High Holborn, in the County of Middlesex,
Fellow of the Institute of Patent Agents, "IMPROVEMENTS IN THE METHOD of
AND APPARATUS FOR DRYING OR DRYING AND COOLING SUGAR AND OTHER
SUBSTANCES (a communication to me from abroad by George Morgan Newhall,
of Philadelphia, Pennsylvania, in the United States of America.)
"
This Invention relates to certain improvements in the method of and apparatus
for drying sugar and other substances, and for cooling the same after they have
been dried, when such cooling is desired.
Complete drying apparatus constructed in accordance with this Invention is
arranged in the manner hereinafter described in a building with three floors.
The substance to be dried is in the first place passed from the upper Hoor through
a pipe. into a drier which is preferably constructed in the manner described herein-
after. Between this drier and the main exhaust air flue there is a branch flue for
carrying off the vapor evolved from the substance during the process of drying.
A single drying machine cannot be relied upon to properly dry substances such
as sugar and the like, for a reason which will be explained hereinafter, hence,
according to the present improvements, there is placed a second drying machine
under the second floor, the substance falling from the drier above through a pipe
into one end of the second drier, from the opposite end of which it is discharged
through another pipe.
This pipe is preferably furnished with a screen, and communicates at the lower
end with a cooler which may consist of a simple cylinder rotated by suitable
gearing, and provided with internal agitating blades or vanes, the discharge pipe
of the cooler leading to any convenient receptacle for the dried material
The second drier is covered so as to form a chamber, into which air is admitted
through a duct at one end of the machine, and escapes at the opposite end of the
machine through another duct which communicates with the said main exhaust air

page_text: flue, so that the air for taking up the moisture evolved from the substance which
is being dried will traverse the said chamber in a direction contrary to that in
which the substance itself is propelled.
Air is admitted to the lower end of the cooler through a duct, the opposite and
higher end of the cooler communicating with the said main air flue which is in
communication with suitable exhausting mechanism.
An important feature of the present invention, especially in connection with the
drying of sugar, is the partial drying in one machine, and the completion of the
drying operation in a second machine, the reason of which is as follows:-
At and towards the end of the drying operation, a fine dust is formed by the
agitation of the dry crystals, and when the entire drying operation is carried on in
one machine, this dust is conveyed by the blast toward the inlet end of the machine
and deposited upon the damp sugar at that point, the dust adhereing to the sugar
through the subsequent operations so as to impair the appearance and detract from
the quality of the finished product.
By the present improved process, the preliminary drying in the first machine is
not carried to such a point as to produce dust, while the crystals which enter the
second machine are not in such a damp condition that dust will' adhere to them.
In the improved machine which is employed for completing the drying operation,
moreover, the tendency of the blast, as above described, is to carry the dust off at
the top of the machine above the surface of the sugar, and thus aid in overcoming
the objection referred to.
The machine whereby the preliminary drying of the sugar is effected, is constructed
as follows:-
In order to obtain a thorough and uniform drying effect, the entire interior
surface of the drum with which the material comes into contact is made as a heating
surface, and for this purpose the drum is composed of an annularly-arranged series
of tubes secured at one end to and communicating with the interior of a hollow
bead, caps being attached to the opposite ends of the tubes.
The outer shell of the head has a central stuffing-box for receiving a portion of
a stationary steam pipe, and through this pipe passes a fixed tube for the escape
of the water of condensation the tube terminating within the head.
To close the spaces between the said annularly arranged tubes, there is used, by
preference, a lining of copper, sheet iron, or other sheet metal or alloy, which is
made to conform with and fit against portions of the tubes, thereby affording an
extended heating surface, and at the same time forming a series of longitudinal
grooves or cavities in which the material under treatment is temporarily lodged as
the drum revolves, the heating effect on the material being thus increased. This
lining is preferably composed of a series of flanged segments bolted or riveted
together, the flanges forming internal blades to raise and let fall portions of the
contents of the drum as the latter revolves.
The circumference of the drum composed of the tubes is practically a continuous
steam jacket, and it should be understood that as far as the main feature of the
present Invention is concerned, other forms of heating jackets may be adopted,
provided they extend all around the drum.
The said lining extends to and is in contact with the said caps at the outer end,
but at the inner end of the drum terminates at some little distance from the said
head, so as to afford a means of escape for the material which is supplied to the
drum at the outer end through a suitable feed spout.
The said tubes are maintained in place by rods bent to form segments and
united by suitable screw couplings, and the drum is also provided with two flanged
rings adapted to carrying rollers on which the whole drum is angularly mounted.
The drum is rotated on these rollers by means of a pinion gearing into a toothed
ring on the periphery of the said head.
Within each of the said annularly arranged tubes is a smaller tube open at both
ends and extending nearly the length of the outer tube, being maintained in its
proper central position within the larger tube by suitable spiders.

page_text: Steam being admitted through the said steam pipe, enters the said head and
circulates through the said larger and smaller tubes expelling the air through the
said tube or pipe through which the water of condensation also escapes when the
drier is in operation.
Instead of closing the spaces between the annularly arranged tubes by a lining
of sheet metal, there may be inserted between the adjoining edges of the tubes
concaved bars, securing tight joints by means of packing, and suitable blades may
be clamped between the bars and tubes.
To prevent radiation of heat, it is preferred to cover the drum with a suitable
non-conducting substance.
The machine for completing the drying operation is constructed with a trough
preferably made of sheet iron with cast iron heads, to the flanges of which the
sheet iron is riveted or otherwise secured, and with a combined stirrer and heater,
consisting of a tube into which are screwed a number of hollow spirally-arranged
blades referred to hereinafter, the tube being fitted at one end into and secured to
a socket forming part of a hollow journal and at the opposite end to a socket on
another hollow journal. The journals are adapted to bearings to which the trough
may be secured, and one of the journals may be furnished with a wheel to be driven
by any available gearing.
The heads of the trough are slotted so as to admit the journals of the stirrer, and
when the journals are in place, plates are so fitted to the heads and to the journals
as to close the ends of the trough.
A steam pipe furnished with a suitable valve or cock passes through the second
mentioned hollow journal and through a stuffing box at the end of the same into
the said tube of the stirrer, an exhaust pipe passing through the other and opposite
hollow journal and this pipe being bent downward within the said tube so as to
receive the water of condensation.
The substance to be dried is introduced through a pipe into the trough at one
end of the same, and is propelled slowly along the trough by the spirally-arranged
blades, escaping finally from the trough through one or other of two pipes as
the position of adjustable gates in said pipes may determine.
The substance which escapes from the trough is dry and hot, and in this condition
it is directed through the one pipe to the cooler or to a suitable receptacle if the
.cooler is not employed.
If it is desired to empty the trough, the valve in the other pipe is opened, and
the substance is discharged through this pipe. By arranging the outlet of the first
mentioned pipe above the bottom of the trough, a mass of the substance is always
maintained in the trough during the operation of the machine, and the effective
action of the stirrers is insured.
Each of the said stirrers consists of a wrought iron tube flattened and closed by
welding at its outer end, the closed end being serrated in order to prevent a smooth
crust from being deposited upon the inner surface of the trough, the serrations
serving to cut up into fine particles the portions of the mass subjected to their
action.
The blades extend into the said tube nearly to the centre of the same, so that
water of condensation in the tube can not gain access to them. The blades are so
arranged that their flattened ends shall be at an angle to the plane of their rotation,
whereby they form propellers and serve to cause the mass to travel from end to
end of the tube as it is being agitated.
In the bottom of the trough is a pipe provided with a suitable valve, the object
of which is to permit the discharge from the trough of water introduced into the.
same for cleansing purposes.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Aubrey Day in the Patent Office on the 21st March,
1884.
"
CHARLES AUBREY DAY, of 321, High Holborn in the County of Middlesex,
Fellow of the Institute of Patent Agents 'IMPROVEMENTS IN THE METHOD OF
AND APPARATUS FOR DRYING OR DRYING AND COOLING SUGAR AND OTHER
SUBSTANCES (a communication to me from abroad by George Morgan Newhall
of Philadelphia, Pennsylvania, in the United States of America.)
"
This Invention relates to certain improvements in the method of and apparatus
for drying sugar and other analogous substances, and for cooling the same after
they have been dried, when such cooling is desired.
On the accompanying drawings, Fig 1 Sheet 1 represents a longitudinal vertical
section, partly in elevation, of drying apparatus constructed in accordance with the
present invention.
Fig 2, a transverse vertical section on the line 1-2.
Fig 3, Sheet 2, a longitudinal section of the primary drying machine forming
part of the apparatus.
Fig 4, a transverse section of the same on the line 3-4.
Fig 5, a transverse section on the line 5-6.
Fig 6, a sectional view illustrating a modification.
Fig 7, a perspective view of part of Fig 6.
Fig 8, (Sheet 3) a vertical section of the machine for completing the drying
operation.
Fig 9, a plan view of the same.
Fig 10, a transverse vertical section on the line 7—8.
Fig 11, a vertical section on the line 9-10.
Fig 12, a view of one of the heads of the cylinder; and Figs 13 and 14. views of
the hollow steam heated stirring and drying blades.
Complete drying apparatus constructed in accordance with this Invention is
represented in Figs 1, and 2, in which w, w¹, and w³, represent the three floors of a
building.
The substance to be dried is in the first place passed from the upper floor w,
through a pipe y, into a drier X, which is preferably constructed in the manner
described hereinafter. Between this drier and the main exhaust air flue M, there
is a branch flue x, for carrying off the vapour evolved from the substance during
the process of drying.
A single drying machine cannot be relied upon to properly dry substances such
as sugar and the like, for a reason which will be explained hereinafter, hence,
according to the present improvements there is placed a second drying machine X',
under the second floor w³, the substance falling from the drier above through a
pipe H, into one end of the second machine X¹, from the opposite end of which it is
discharged through a pipe I.
This pipe is preferably furnished with a screen W, and communicates at the
lower end with a cooler X³, which may consist of a simple cylinder P, rotated by
suitable gearing, and provided with internal agitating blades or vanes, the s
discharge pipe Q, of the cooler leading to any convenient receptacle for the dried
material.
It will be seen on referring to Fig 2, that the drier X¹, is covered so as to form
a chamber a', into which air is admitted through a duct ³, at one end of the

page_text: machine, and escapes at the opposite end of the machine throug a duct ³, which
communicates with the main exhaust flue M, so that the air for taking up the
moisture evolved from the substance which is being dried will traverse the
chamber, in a direction contrary to that in which the substance itself is
propelled.
Air is admitted to the lower end of the cooler X* through a duct a, Figs 1
and 2 the opposite and higher end of the cooler communicating with the main
flue M, which is in communication with suitable exhausting mechanism.
An important feature of the present invention, especially in connection with the
drying of sugar, is the partial drying in one machine, and the completion of the
drying operation in a second machine, the reason of which is as follows:-
At and towards the end of the drying operation a fine dust is formed by the
agitation of the dry crystals, and when the entire drying operation is carried on
in one machine, this dust is conveyed by the blast toward the inlet end of the
machine and deposited upon the damp sugar at that point, the dust adhering to the
sugar through the subsequent operations so as to impair the appearance and detract
from the quality of the finished product.
By the present improved process the preliminary drying in the first machine is
not carried to such a point as to produce dust, while the crystals which enter
the second machine are not in such a damp condition that dust will adhere
to them.
In the improved machine which is employed for completing the drying operation,
moreover, the tendency of the blast as above described is to carry the dust off at
the top of the machine above the surface of the sugar, and thus aid in overcoming
the objection referred to.
The machine whereby the preliminary drying of the sugar is effected, is shown
in detail in Figs 3, to 7. of the drawings, and is constructed as follows:-
:-
In order to obtain a thorough and uniform drying effect, the entire interior
surface of the drum with which the material comes into contact is made as a
heating surface, and for this purpose the drum is composed of an annularly
arranged series of tubes B, secured at one end to, and communicating with the
interior of a hollow head A, caps D, being attached to the opposite ends of
the tubes.
The outer shell of the head A, has a central stuffing-box for receiving a portion of
a stationary steam pipe E, and through this pipe passes a fixed tube F, for the escape
of the water of condensation, the tube terminating within the head at or about the
point shown in Fig 3.
To close the spaces between the annularly arranged tubes B, there is used by
preference a lining G, of copper, sheet iron, or other sheet metal or alloy, which, as
shown in Fig 4, is made to conform with and fit against portions of the tubes B.
thereby affording an extended heating surface and at the same time forming a
series of longitudinal grooves or cavities in which the material under treatment is
temporarily lodged as the drum revolves, the heating effect on the material being
thus increased. This lining is preferably composed of a series of flanged
segments bolted or rivetted together, the flanges g, forming internal blades to raise
and let fall portions of the contents of the drum as the latter revolves.
The circumference of the drum composed of the tubes is practically a continuous
steam jacket, and it should be understood that as far as the main feature of the
present invention is concerned, other forms of heating jackets may be adopted,
provided they extend all around the drum.
The lining G, extends to and is in contact with the caps D, at the outer end,
but at the inner end of the drum terminates at some little distance from the
head A, so as to afford a means of escape for the material which is supplied to the
drum at the outer end through a suitable feed spout, indicated by dotted lines in
Fig 3.

page_text: The tubes B, are maintained in place by rods d, bent to form segments and
united by suitable screw couplings d', (Fig 4), and the drum is also provided with
two flanged rings J, J, adapted to carrying rollers h, h¹, on which the whole drum
is mounted at about the angle shown in Fig 3. The drum is rotated on these rollers
by means of a pinion K, (Fig 5) gearing into a toothed ring L, on the periphery
of the head A.
Within each of the tubes B, is a smaller tube b, open at both ends and extending
nearly the length of the outer tube and maintained in its proper central position
within the larger tube by suitable spiders b¹, 61.
Steam being admitted through the pipe E, enters the head A, and circulates
through the larger and smaller. tubes B, b, expelling the air through the pipe F,
through which the water of condensation also escapes when the drier is in
operation.
Instead of closing the spaces between the tubes B, by a lining of sheet metal,
there may be inserted between the adjoining edges of the tubes concaved bars N,
Figs 6 and 7. securing tight joints by means of packing, and suitable ble blades g¹,
may be clamped between the bars N and tubes.
To prevent radiation of beat it is preferred to cover the drum with a suitable
non-conducting substance.
The machine X', for completing the drying operation is illustrated in Figs 8.
to 11, and is constructed with a trough S, preferably made of sheet iron with cast
iron heads S¹, to the flanges of which the sheet iron is rivetted or otherwise
secured, and with a combined stirrer and heater T, consisting of a tube a, into
which are screwed a number of hollow spirally-arranged blades a¹, referred to
hereinafter, the tube being fitted at one end into and secured to a socket e, forming
part of a hollow journal R, and at the opposite end. to a socket on a hollow
journal R'. The journals are adapted to bearings U, U, to which the trough S,
may be secured, and one of the journals may be furnished with a wheel f, to be
driven by any available gearing.
The heads of the trough are slotted at i, as shown in Fig 12, so as to admit the
journals of the stirrer, and when the journals are in place, plates v, are so fitted to
the heads and to the journals as to close the ends of the trough.
A steam pipe k, furnished with a suitable valve or cock passes through the
journal R¹, and through a stuffing box at the end of the same into the tube a, of
the stirrer, an exhaust pipe k¹, passing through the opposite journal R, and this
pipe being bent downward within the tube a, so as to receive the water of
condensation.
The substance to be dried is introduced through a pipe m, into the trough at
one end of the same, and is propelled slowly along the trough by the spirally-
arranged blades, escaping finally from the trough through the pipe n, or the pipe n¹,
Fig 10, as the position of adjustable gates p, p, in said pipes may determine.
The substance which escapes from the trough is dry and hot, and in this
condition it is directed through the pipe n, to the cooler X³, or to a suitable
receptacle if the cooler is not employed. If it is desired to empty the trough S,
the valve in the pipe n¹, is opened, and the substance is discharged through this
pipe. By arranging the outlet n, above the bottom of the trough, a mass of the
substance is always maintained in the trough during the operation of the machine,
and the effective action of the stirrers is insured.
The stirrers a¹, are constructed in the manner shown in Figs 13, and 14, each
stirrer consisting of a wrought iron tube flattened and closed by welding at its
outer end, and the closed end being serrated in order to prevent a smooth crust
from being deposited upon the inner surface of the trough S, the serrations
serving to cut up into fine particles the portions of the mass subjected to their
action..
.
[
The blades extend into the tube a, nearly to the centre of the same, so that
water of condensation in the tube cannot gain access to them. The blades are so

page_text: arranged that their flattened ends shall be at an angle to the plane of their
rotation, whereby they forin propellers and serve to cause the mass to travel from
end to end of the tube as it is being agitated.
In the bottom of the trough S, is a pipe w, provided with a suitable valve, the
object of which is to permit the discharge from the trough of water introduced
into the same for cleansing purposes.
Having thus particularly described and ascertained the nature and objects of
the said Invention and in what manner the same is to be or may be performed or
carried into practical effect I would observe in conclusion that what I consider
to be novel and original and therefore claim as constituting the Invention secured
to me by the hereinbefore in part recited Letters Patent is:-
1. The mode herein before described of effecting the drying of sugar and like
substances, said mode consisting in subjecting the said substances to heat and
agitation in one machine to effect a partial drying of the same, and then transferring
the partially dried substances to a second machine, and subjecting them to further
heat and agitation to complete the drying operation, substantially as set forth.
2. A drier in which a drum, the entire circumference of which consists of a heated
jacket, is combined with mechanism for rotating the said drum, substantially as
herein before set forth.
3. A drying drum composed of a series of heated tubes forming the circumference
of the drum, substantially as herein before specified.
4. A drying drum in which annularly arranged heating tubes are combined
with means for closing the spaces between the tubes, substantially as hereinbefore
set forth.
5 The combination of the hollow head A, the tubes B, communicating there with
at one end, and closed at the opposite end, with steam inlet and outlet in the said
head, and smaller tubes 6, within the said tubes B, substantially as hereinbefore
described.
6. The combination of. a hollow head A, the annularly arranged tubes B,
constituting a drum, with binding rods d, substantially as herein before set forth.
7. A drying drum composed of a series of annularly-arranged tubes B, and
provided with a sheet metal lining G, fitted to the tubes within the drum,
substantially as herein before described.
8. A drying drum composed of a series of annularly-arranged tubes combined with
flanged segments of sheet metal, substantially as hereinbefore described.
9. A drying drum composed of a hollow head A, inlet and outlet, and a series of
annularly-arranged tubes B, with sheet metal lining discontinued at and near the
head so as to afford outlets for the material, substantially as hereinbefore
described.
10. The combination of the trough S, with the steam-heated rotating tube a,
having hollow, spirally-arranged blades a¹, inclined at the ends whereby they are
adapted to serve as propellers, substantially as hereinbefore set forth.
11. The combination of the trough S, with the steam heated tube a, and its
hollow blades a¹, closed and serrated at the outer ends, substantially as hereinbefore
set forth.
12. The combination of the trough S, with the steam heated tube a, having hollow
blades a¹, closed at the outer ends, and projecting inwardly beyond the inner
surface of the tube, whereby the water of condensation is prevented from gaining
access to the blades, substantially as hereinbefore set forth.
13. The combination of the stirrer T, having projecting blades a¹, with the
trough S, having an outlet n, between the top and bottom, substantially as
hereinbefore set forth.
14. The combination of the stirrer T, having blades a¹, with the trough S, having
an outlet n, between the top and bottom, and a valved outlet n¹, at the bottom,
substantially as hereinbefore set forth.

page_text: 15. The combination of the steam-heated stirrer T, having journals R, R¹, with
bearings for the latter, and with a trough S, having slotted heads S¹, and removable
plates adapted to the said heads and to the journals of the stirrer, substantially
as herein before set forth.
16. The combination of a drying cylinder with a rotary cooler, substantially as
hereinbefore set forth.
In Witness whereof, I, the said Charles Aubrey Day, have hereunto set my hand
and seal this 18th day of February in the year of our Lord One thousand eight
hundred and eighty four.
CHARLES AUBREY DAY. (L.S.)