Improved Methods and Apparatus applicable to the Drying or Desiccation of Cereals and other Materials.
Year: 1892

page_text: Date of Application, 17th May, 1892
Complete Specification Left, 6th Mar., 1893-Accepted, 22nd Apr.. 1893
PROVISIONAL SPECIFICATION.
Improved Methods and Apparatus applicable to the Drying or
Desiccation of Cereals and other Materials.
I, WILLIAM VAN VLECK LIDGERWOOD, of 96 Liberty Street New York,
United States of America, Manufacturer do hereby declare the nature of this
invention to be as follows:-
My invention relates to improved methods and apparatus applicable to the
drying or desiccation of cereals and other materials such as spices, coffee, beans,
rice, small fish, other small articles, or finely divided substances.
The principal object of my said invention is to provide for the efficient and
expeditious drying of such materials by heated air in apparatus which is capable
of being erected, maintained, and efficiently operated, at a moderate cost and by
unskilled labour.
Other objects of my said invention are to perform the said drying with a greater
economy of heat than is possible in the apparatus hitherto employed for the like
purpose, and to arrange the said improved apparatus so that losses from radiation
may be minimised.
Another object of my said invention is to provide apparatus in which the
material, while under treatment, is enclosed so that it cannot be pilfered, the
delivery of the said material into the apparatus, its transfer between the various
parts thereof, and its discharge from the same, being effected mechanically and by
gravity so that it is not touched by hand.
A further object of my said invention is to construct the said improved apparatus
in such a manner that its several parts are conveniently portable in districts in
which the transport of weighty and bulky material would present difficulties.
According to my present invention I provide within a vertical chamber a number
of inclined shelves of perforated metal or of wire gauze. The said shelves are
arranged in pairs, the two shelves of each pair being hinged to opposite walls of
the chamber. The hinges of each said pair of shelves are arranged at equal
distances from the bottom of the chamber and the shelves slope downward towards
each other and towards the centre of the chamber at an angle which may be varied
as desired, by suitable adjusting mechanism operated from the exterior of the
chamber. Alteration of the said angle will vary also the width of the opening
between the contiguous edges of opposite shelves of each pair. The said chamber
is provided with suitable connections whereby currents of heated air from any
suitable kind of air-heater may be caused to travel across the chamber, between
the pairs of shelves or to travel upward or downward through the said chamber, so
as to desiccate the material which is spread upon them. The said material is fed
in through a suitable opening at the upper end of the chamber, and the said
inclined shelves are adjusted so that the material gravitates through the apparatus
to an exit orifice at the lower end which normally is closed. The material when
thus introduced, spreads itself upon the several shelves, to a depth upon each which
brings the material on any pair of shelves into contact with the material in the
opening between the pair of shelves next above it. Thus the air currents in passing
across the charged chamber are compelled to pass through the material therein.
As an alternative, the chamber, instead of being vertical, is inclined, and is
subdivided by suitable perforated plates or sheets of wire gauze into a number of
Sinaller inclined chambers, in each of which is an inclined perforated tray upon
which the material to be dried is placed. The several smaller chambers are
provided with suitable openings for the admission and withdrawal of the said
material and with suitable tubes for the admission and withdrawal of heated air.

page_text: There may either be separate air tubes for each of the smaller chambers, or the
inclined plates and trays may be so arranged that the air may be led through the
several smaller chambers in succession.
The inclination of the said perforated trays in the inclined chambers is preferably
such that the material will gravitate from them through passages at the lower ends
of the trays when the said passages are opened.
As another alternative, I provide a vertical chamber, within which a series of
perforated or other shelves are placed which slope downward from the walls
towards each other and beyond the centre of the chamber. The said plates are
placed alternately, at different heights at opposite sides of the chamber, and are so
arranged that the material fed into the top of the chamber travels down over them
in a zig-zag path to an outlet orifice at the bottom. The inclination of the said
shelves is such that if the said outlet be closed so that the sliding of the material
on the lowermost shelf be prevented, a continuous zig-zag layer of the said material
will lie upon the several shelves. But if the material be allowed to slide from the
said lowermost shelf, it will gravitate downward from the shelves above.
The said chamber is provided with suitable inlet and outlet passages for heated
air, which may be drawn transversely or upward or downward through the layers
of material in the chamber.
Preferably I provide a rotary delivery-wheel, or conveyor or the like, at the said
outlet orifices of the chambers hereinbefore described and operate the same to
withdraw the material therefrom slowly and continuously and I may provide
similar means at the upper end of the chamber to feed material thereinto.
The material from either of the said chambers may either be allowed to gravitate
or may be otherwise conveyed through suitable passages, into suitable drying
chambers, preferably provided with rotatable floors, or may gravitate or be otherwise
delivered into a hopper from which the supply of material for the said rotatable
floor is drawn or into other suitable receptacles.
It is an important feature of my said invention that all the said drying chambers
and the tubes by which the heated air is led thereinto and withdrawn therefrom
and the air-heating device are lagged with a material such as asbestos for example,
which offers resistance to the radiation of heat.
Another important feature of my said invention is the provision of a suitable centri-
fugal fan, air-blower, or air-exhauster, and of a series of hoppers or receptacles to
receive the material before and after treatment and the provision of suitable ducts or
tubes in combination therewith and with air-heating apparatus and provided with
suitable valves, so that the said fan, blower or exhauster, may be employed at different
times, to create air currents in the said ducts or tubes, which currents deliver the
material into hoppers from which it may be fed into the chambers hereinbefore
described, and to pass the air through the heating apparatus and the said drying
chambers, and to effect such transference of material from one part of the apparatus
to another as may be required.
To effect economy in the use of the heated air I preferably arrange that the air
is led successively through several chambers of the kind herein before described,
increasing its humidity on its way through the series, and I-arrange suitable pipe-
connections and valves so that the air from the air-heater may be led first into any
one of the series and afterwards to others of the said series, in such order as may be
desired.
An important adjunct, which also acts to effect economy in the use of the heated
air will now be described :-In a suitable chamber a number of tubes or plates are
provided, and the humid waste air which has passed through the drying chamber or
chambers as aforesaid, is led into contact with the one side of the said tubes or
plates, and cooler air is caused to pass in contact with the opposite sides of the said
tubes or plates. Thus the moisture contained in the humid air is condensed and
heat is imparted to the air by which the condensation is effected. The air thus
warmed is afterwards led to the air-heater and further heated. It is evident that
the preliminary heating of the air-supply, by the condensation of the moisture in the

page_text: waste air utilizes heat which would otherwise be wasted, and thus, an
economy is affected
important
waste air utilizes heat which would otherwise be wasted, and thus, an important
is affected
Suitable sight-holes are provided in the different parts of the apparatus, so that
the interior may be inspected.
I do not limit my invention to the particular details of the methods and apparatus
herein before described which may be varied without departing from my said
invention.
Dal 17 I. ff. 1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improved Methods and Apparatus applicable to the Drying or
Desiccation of Cereals and other Materials.
I, WILLIAM VAN VLECK LIDGERWOOD, of 96 Liberty Street, New York,
United States of America Manufacturer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
My invention relates to improved methods and apparatus applicable to the drying
or desiccation of cereals and other materials such as spices, coffee, beans, rice, small
fish, and other small articles or finely divided substances.
The principal object of my said invention is to provide for the efficient and
expeditious drying of such materials by heated air in apparatus which is capable of
being erected, maintained and efficiently operated at a moderate cost and by
unskilled labour.
Other objects of my said invention are to perform the said drying with a greater
economy of heat than is possible in the apparatus hitherto employed for the like
purpose, and to arrange the said improved apparatus so that losses from radiation
may be minimised.
Another object of my said invention is to provide apparatus in which the
material, while under treatment is enclosed so that it cannot be pilfered, the
delivery of the said material into the apparatus, its transfer between the various
parts thereof, and its discharge from the same being effected mechanically and by
gravity so that it is not touched by hand.
A further object of my said invention is to construct the said improved apparatus
in such a manner that its several parts are conveniently portable in districts in
which the transport of weighty and bulky material would present difficulties.
In order that my said invention may be clearly understood I will now proceed
to describe the same with reference to the accompanying drawings, in which.
Figure is a vertical section of an improved drying chamber constructed
according to my invention.
Figure 2 is a section of the apparatus illustrated in Figure 1, on the line of
that figure.
1
Figure 3 is a diagram illustrating in side elevation a complete drying-plant also
constructed according to my invention.
Figure 4 is a plan and
Figure 5 is an end elevation of the apparatus illustrated in Figure 3.
With reference first to Figures 1 and 2.
A is a vertical chamber, B, B, are shelves of perforated metal or of wire
gauze, C, C. are shafts to which the shelves B are secured as shown, and which
turn in bearings D provided in the walls of the chamber. E, E are arms secured
to the ends of the rods C and connected by rods F for a purpose hereinafter set
forth. The said arms can be counterweighted if desired, and the arms,at opposite
sides of the apparatus can be connected by a chain or rope passing over suitable
pulleys, to enable them to be operated simultaneously.

page_text: GG are hoppers in which material to be dried is placed for delivery to the-
chamber A by way of passages G¹.
His a screw-conveyor, placed at the lowest point in the chamber A for with-
drawing material therefrom by way of the passage A' after treatment, I is an inlet
for hot air delivered thereto by any suitable kind of air-heating apparatus and fan
or blower, J is an outlet passage by which the hot air passes from the chamber A
after its utilization therein in the manner hereinafter set forth. The arrangement.
of the said inlet and outlet passages may be varied as desired in accordance with the
path which the hot air is required to follow in traversing the chamber.
The chamber A is provided with double walls between which a packing A'
of suitable material is placed to prevent as far as is possible loss of heat by
radiation.
The shelves B when in use slope down and towards the centre of the chamber at
an angle which may be varied as desired by moving the shafts C by means of the
rods F. Alteration of the said angle will vary also the width of the opening
between the contiguous edges of opposite shelves.
The material to be treated is fed into the chamber A from the hoppers G, and
gravitates to the lower portion of the chamber, loading the shelves B in the manner
indicated in Figure 1, the inclination of the said shelves being so regulated that
the material on each pair of opposite shelves is in contact with the material in the
opening between the pair of shelves next above. Currents of heated air from
the inlet I are then delivered into the chamber A and are compelled to pass
through and desiccate the material therein, to get to the outlet J.
The conveyor H is employed to withdraw the material slowly and continuously
from the bottom of the chamber A through the passage A1 and the shelves B are
kept charged by the gravitation of material into the chamber from the hoppers G
which should be kept full, so that the material in course of treatment moves slowly
and continuously through the chamber from top to bottom. A conveyor or similar
device can be advantageously employed to keep the hoppers G charged.
The material from the drying-chamber hereinbefore described may either be
allowed to gravitate or may be otherwise conveyed through suitable passages into
suitable drying chambers, preferably of the well-known kind provided with rotatable
floors, or may gravitate or be otherwise delivered into a hopper from which the
supply of material for the said rotatable floor is drawn, or it may be delivered into
other suitable receptacles.
It is an important feature of my said invention that the aforesaid drying chamber
and the tubes by which the heated air is led thereinto and withdrawn therefrom
and the air-heating device are lagged with a material such as asbestos for example
which offers resistance to the radiation of heat.
Another important feature of my said invention is the provision of a suitable
centrifugal fan, air-blower or air-exhauster and of a series of hoppers or receptacles
to receive the material and the provision of suitable ducts or tubes in combination
therewith and with air-heating apparatus provided with suitable valves, to pass
the air through the heating apparatus and the said drying chambers.
To effect economy in the use of the heated air I preferably arrange that the air
is led successively through several drying chambers, increasing its humidity on its
way through the series, and I arrange suitable pipe-connections and valves so that
the air from the air-heater may be led first into any one of the series and afterwards
to others of the said series in such order as may be desired.
An important adjunct, which also acts to effect economy in the use of the heated
air will now be described :-
In a suitable chamber a number of tubes or plates are provided, and the humid
waste air which has passed through the drying chamber or chambers as aforesaid
is led into contact with the one side of the said tubes or plates, and cooler air is
caused to pass in contact with the opposite sides of the said tubes or plates, the said
apparatus constitutes a surface-condenser. Thus the moisture contained in the
humid air is condensed and heat is imparted to the air by which the condensation

page_text: is effected. The air thus warmed is afterwards led to the air heater and further
heated. It is evident that the preliminary heating of the air supply, by the con-
densation of the moisture in the waste air, utilizes heat which would otherwise be
wasted and thus an important economy is effected. With reference now to
Figures 3, 4 and 5 in which one arrangement of apparatus according to my inven-
tion is shown, embodying the said adjunct which is hereinafter termed a heating
house, A, A are vertical drying chambers of the kind herein before described with
reference to Figures 1 and 2. They are arranged in a heating house K, in one
compartment K thereof.
Land M are separate drying chambers of a well-known type having rotatable
floors.
N is a pipe leading from the compartment K¹ to an air-heater N¹ of any suitable
type.
O is a pipe leading from the said air-heater to a fan P. and thence to a space
below a perforated floor in the chamber L.
Qis a pipe leading from the space above the perforated floor of the chamber L
to a space below the perforated floor in the chamber M. Q¹ is a valve in the
pipe Q.
R is a pipe leading from the space above the perforated floor of the chamber M
to a fan R¹ and thence to a series of thin metal tubes S within the compartment K³
of the heating house K which tubes communicate at S¹ with the atmosphere outside
the heating house K.
T is a pipe leading from the space above the perforated floor in the chamber M
back into the drying house K. A valve is placed in the said pipe at T.
In the operation of the said apparatus the fan P is put in motion and causes air
to flow from outside the heating house K, through a suitable aperture into the said
house and through the material in the chambers A in the compartment K', and
from the said chambers through pipe N and the heater N', thence by the pipe O
into the drying-chamber L. After acting upon the material in the said drying-
chamber it can be caused, by closing the valve Q¹ and opening the valve T¹ to
return to the heating-house K and re-circulate as before, or by opening the
valve Q and closing the valve T¹ the air is caused to pass from the chamber L
by the pipe Q into the chamber M and through the material therein. From the
said chamber M it is drawn by the fan R' and forced thereby through the pipe R
to the pipes S in the heating-house K. It heats the said pipes S and thus dries
and heats the fresh air drawn into the house K, as aforesaid, from the atmosphere
and caused to pass into contact with the outsides of the pipes S before passing to
the drying chambers A. In thus heating the pipes S it parts with its own moisture
by condensation as aforesaid.
Suitable sight holes are provided in the different parts of the apparatus, so that
the interior may be inspected.
For the heating-house K I may substitute any suitable surface condenser which
will act in a like manner.
I do not limit my invention to the particular details of the methods and
apparatus hereinbefore described which may be varied without departing from my
said invention.
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 :-
1. An improved drying-chamber with hinged shelves arranged opposite to each
other therein and with passages for the entry and exit of heated air, substantially
as herein before described, for the purposes specified.
2. The said improved drying chamber in combination with apparatus for with-
drawing the dried material therefrom, substantially as hereinbefore described, for
the purposes specified.
3. The combination with a series of drying chambers A having hinged shelves

page_text: of drying chambers having rotatable floors, a heating-house, fans, air heaters, and
pipe connections and valves, substantially as herein before described for the purposes
specified.
4. A drying-house substantially as hereinbefore described with reference to
Figures 1 and 2 of the accompanying drawings for the purposes specified.
5. The combination of apparatus constituting an improved drying-plant,
substantially as herein before described with reference to Figures 3, 4 and 5 of the
accompanying drawings, for the purposes specified.
Dated this 6th day of March 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.