Improvements in the Method of and Apparatus for Drying Semi-fluid and like Materials.
Year: 1895

page_text: Date of Application, 30th Nov., 1895
Complete Specification Left, 30th Sept., 1896-Accepted, 31st Oct., 1896
TRUVIDIONAL DUTTIVATION.
[Communicated from abroad by J. HUNDHAUSEN, D.Ph., of Hamm, Westphalia, in
the German Empire, Chemical Engineer.]
Improvements in the Method of and Apparatus for Drying
Semi-fluid and like Materials.
I, WILLIAM EDWIN HEYS of 70 Market Street Manchester in the County of
Lancaster, Patent Agent, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the method of and apparatus for drying semifluid and like
substances, such as syrups, slurry, and various muddy products.
According to this invention the substances to be dried are fed in thin layers upon
rotating surfaces or cylinders which may be internally or externally heated or both,
with or without the assistance of an air current.
In one form of apparatus there may be two drying cylinders mounted upon a
shaft which has bevel pinions fixed upon its ends. These two pinions gear with
the teeth of a horizontal bevel wheel or wheels rotated by any convenient means.
In another form of the apparatus, the drying cylinders may be transversely
mounted in a circular rotary frame at the centre of which there may or may not be
a ventilating fan for producing a current of air to aid the drying. In this case the
rollers may be rotated by means of pegs or the like arranged upon them or their axes
which pegs come into contact with a series of projections arranged around the rotary
frame whereby the cylinders are rotated after the manner of a star wheel.
In yet another arrangement, the drying cylinders may be arranged in parallel
vertical rows within a chamber suitably heated and ventilated.
It will be obvious that many other arrangements of the drying cylinders may be
employed in such a manner that the material to be dried thereon may be supplied to
their rotating surfaces, from which it finally drops or is scraped off.
Dated this 90th day of November A D 1895
COMPLETE SPECIFICATION.
Improvements in the Method of and Apparatus for Drying
Semi-fluid and like Materials.
I, WILLIAM EDWIN HEYS, of 70, Market Street, Manchester, in the County of
Lancaster, Patent Agent, do hereby declare the nature of this invention, and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
This invention relates to the method of and apparatus for drying semi-fluid and
like substances, such as syrups, slurry, and various muddy products.
According to this invention, the substance to be dried is fed in thin layers upon
rotating surfaces or cylinders which may be internally or externally heated, or both,
with or without the assistance of an air current.

page_text: It will be obvious that many arrangements of the drying cylinders may be employed
in such a manner that the material to be dried thereon may be supplied to their
rotating surfaces, from which it finally drops or is scraped off.
As
By depositing the substance in uniform thin layers upon the rotating cylinders it is
prevented from flowing and is in the best condition for giving up its moisture.
the layers of material being dried are to be very thin it follows that the cylinders
must not be heavy and require considerable driving power, and that their surfaces
must be perfectly smooth, as irregularities produce corresponding irregularities in the
thickness of the layer. Hence, when the ordinary thickness of the layer is dried and
drops off, a thicker part will not be dry and will continue to adhere to the cylinder
and will exaggerate the defect in successive layers of the material coming on the
cylinder to be dried.
The following three conditions have to be observed. 1. The surface of each cylinder
must be as large as possible. 2. Each cylinder must be rotatable with a small
expenditure of energy. 3. The surfaces of the cylinders must be as smooth as
possible.
.
+
These conditions must be borne in mind in the construcțion :-I. of the cylinders,
and II. of the whole system.
1. The cylinders can not be constructed of cast metal nor of riveted or soldered
sheets, because the cylinder would in the first case be too heavy, and in the second
place its surface would not be sufficiently smooth. Each cylinder should have a
diameter of at least 12 inches and it cannot therefore conveniently be drawn or
pressed in one piece. I find that the cylinder is. therefore best constructed of thin
sheet metal with the edges of the metal electrically welded. The seam produced is
reduced by grinding it down. A cylinder so constructed, having a length of 6 ft.
6 in., and a circumference of 3 ft. 3 in., may have a weight of only 22 lbs.
LI. The system which 1 prefer to employ is illustrated by the accompanying
drawings and hereinafter described with reference thereto. In these drawings:-
Figure 1 represents a vertical section and
Figure 2 a sectional plan.
The ends of the cylinders Care fitted with centres on which are formed or secured
coaxial toothed pinions S S, carrying spindles upon which the cylinders are mounted.
The series of cylinders C are mounted, parallel with each other upon and between
two parallel frames B B upon which the pinions S S can run, and by means of
which the cylinders will be caused to rotate. This arrangement is found to be
preferable to that of a rack on the frames gearing with the wheels S S, inasmuch
as the linear expansion of the rack under heat increases the pitch of the rack teeth
and prevents perfect gearing and smooth action. Parallel with and outside the
frames B. B there are endless chains running upon the chain wheels K K' of
which the wheels K have their axes in fixed bearings and the other K' in adjustable
bearings, so that the chains may be kept tight with variations of temperature by
moving the bearings of K' further from or nearer to K, by means of the hand-
wheels ww, as may be required. The chains carry at suitable intervals, loose
spindles R which are fitted into the holes in the wheels S and the centres of the
cylinders. The wheel K being rotated by suitable power and gearing, the whole
system of cylinders is caused to travel around the frames B B, and are at the same
time caused to rotate around their axes by the contact of their wheels with the
frames. The frames are made adjustable together with the wheel K¹, and for the
same reason, by means of an overlapping joint.
The apparatus is arranged within a chamber A through an opening. E. in which
the material can be supplied to the rollers. Between the ends of the series of
cylinders there may be arranged suitable heating appliances, such as. steam pipes,
and at F there may be an inlet for hot air which may be forced by a fan or
blower.
The horizontal arrangement is that which is preferred to be adopted, but a
vertical' arrangement may be employed and in such a case, parallel vertical systems
may be emploved.

page_text: The number of cylinders will in every case be determined by the nature and
amount of work to be done, and in the simplest cases there may be two only of
such cylinders.
Also, instead of using fixed frames as hereinbefore described, and as preferred,
circular rotary frames may be employed, but as the effect produced is inferior, it
is unnecessary to describe them further.
When the material is dry, it falls from the cylinders into the bottom of the
chamber whence it may be removed by endless travelling aprons or otherwise as
is well understood.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. In drying apparatus, for syrups and like semi-fluid materials, a series of two
or more rotating cylinders externally or internally heated upon which the material
is fed in a uniform thin layer, and from which it falls when dry, constructed and
arranged substantially as herein before described with reference to the accompanying
drawings.
2. Drying apparatus for syrups and similar semi-fluid substances, consisting
essentially of a series of cylinders exposed to heat and upon which the material is
fed in a thin layer or layers, constructed and arranged substantially as herein before
described and as illustrated by the accompanying drawings.
Dated this 29th day of September 1896.
WILLIAM E. HEYS.