Improvements in the Method of and Apparatus for Drying Sensitive Substances.
Year: 1895

page_text: Date of Application, 30th Nov., 1895
Complete Specification Left, 30th Sept., 1895-Accepted, 31st Oct., 1896
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 Sensitive
Substances.
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 chemically
and physically sensitive substances such as starches and the like.
The apparatus constructed according to these improvements consists of one or
more rotary cylinders which are continuously fed. They are preferably contained
within a chamber and heated internally and externally. The surfaces of the
cylinder or cylinders which come into contact with the material to be dried are
constructed of or covered with a suitable material which will resist the heat
When more
employed and will not act upon or be acted upon by, the material.
than one cylinder, is employed, they are arranged in a vertical plane. The material
is dried by being caused to pass through the heated cylinder, or successively
through the series of cylinders, in each of which there may be, arranged a stirring
or agitating appliance. At the same time there is caused to pass through the
cylinder or cylinders a current of. air. which carries away the evaporated moisture.
In the case of a vertical series of cylinders the material is supplied to one end
of the highest cylinder whence it passes out at the opposite end through a shoot
or the like into the cylinder next below, and thus through the whole series to the
delivery end of the lowest cylinder.
Dated thin 20th dog of November AD 1895.
COMPLETE SPECIFICATION.
Improvements in the Method of and Apparatus for Drying Sensitive
Substances.
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 chemically
and physically sensitive substances such as starches and the like.
An apparatus constructed according to these improvements consists of one or
more rotary cylinders which are continuously. fed. They are preferably contained
within a chamber and heated internally and externally. The surfaces which come
into contact with the material to be dried are constructed.or.covered with a suitable
material which will resist the heat employed and will not act upon or be acted on by

page_text: •
the material. When more than one cylinder is employed they are arranged in a
vertical plane. The material is dried by being caused to pass through the heated
cylinder if only one be employed, or, in other cases, through the cylinders
successively. A stirring or agitating appliance may be employed in combination
with each cylinder. At the same time with the material there is caused to be
passed through the cylinder a current of air which carries away the evaporated
moisture.
In the case of a single cylinder, the material is supplied to one end and delivered
from the other. In the case of a vertical series of cylinders, the material is
'supplied to the highest and passes out of its opposite end through a shoot or the
like to the cylinder next below, and thus through the whole series to the delivery
end of the lowest cylinder.
The cylinder which I may employ in a series is illustrated in cross sectional
end elevation by Figure 1 of the accompanying drawings.
C is the hollow tubular centre, upon which, at opposite euds, there are fixed
metallic brackets N. Opposite brackets are connected by the clamps H, consisting
of flat strips of wood. These clamps are secured to the projections by means of
the radial studs R, screwed at each end, and having secured at their outer ends a
pair of clamps H¹ similar to and parallel with the clamps H. Two collars h h on
the studs act as distance pieces between the inuer and the outer pair of clamps.
A ribbon or strip of cloth is secured in each pair of clamps, and to the projecting
edges of this strip or ribbon, on each side of the clamps, strips of cloth T T¹ or
other suitable material are connected, thus producing a polygonal chamber forming
the drying space of the cylinder. This polygonal chamber may advantageously
be divided up into longitudinal compartments, open at the ends, by means of radial
partitions T2 adjoining the clamps, and this prevents the occurrence of any nooks
or obstructions which might impede the regular passage of the materials during
drying.
In cases where it is desired to employ the same apparatus for successively drying
different materials, pigments for example, and in which cases the strips T T
would have to be changed, the modified construction illustrated in cross section by
Figure 2 may be employed. Dovetailed recesses N' are formed upon the tubular
centre C, and the cloth or other material forming the polygonal chamber is stretched
and secured upon a framing having dovetailed feet which fit into the dovetailed
recesses, as indicated. With this construction, the external part of the drying
cylinder can be removed and replaced at will, in a very short time. Figures 3
and 4 illustrate in vertical section and end elevation respectively, a drying system
consisting of a series of three cylinders. Other numbers may be similarly arranged.
These cylinders are arranged within a closed chamber adapted to conserve the heat
therein, and provided with suitable orifices for the admission and escape of the
material to be dried, and for air. Of course provision will be made in constructing
the chamber to provide means of access and for the removing and replacement of
the cylinders.
Steam may be admitted through the centres of the cylinders by means of the
pipes D and trunnions E, and the rotation of the cylinders may be effected by
an endless chain F and the chain wheels G, one of which may be driven by any
suitable means. On each side of the cylinders and parallel with their vertical
plane, there may be arranged a series of steam heating tubes I, which are preferred
not to extend to the ends of the cylinders, these being preferably separated from
the heating space by the vertical partitions J J, through which the ends of the
cylinders pass. Air enters the chamber at L' L' on the same side as the material is
fed and escapes on the opposite side by the flue L. The material is supplied to the
top cylinder through the hopper E', and leaves it at the opposite end.
To facilitate the passage of the material through the apparatus, each cylinder
may have its axis inclined slightly downwards in the direction of the travel, and
in order to promote the drying in the first cylinder, it is advantageous to arrange
a special inlet of air under pressure, in fine jets or streams, through a pipe such

page_text: as M, these streams of air being directed, preferably, against the cloth. If the
material possesses a tendency to clog or ball when leaving the first cylinder, there
may be provided a pair of rollers or crushers V upon which the material is com-
pelled to fall as indicated by the arrow, if the material is amenable to such
treatment.
The material is guided into the cylinders by means of shoots or inclined planes S,
and its course through the apparatus from the hopper E to the outlet O, is indicated
by arrows, Figure 3.
said inven-
Having now particularly described and ascertained the nature of my
tion and in what mauner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is:-
1. Drying cylinders for sensitive substances, constructed and operated substan-
tially as hereinbefore described and as illustrated by the accompanying drawings.
2. A drying system for sensitive substances, consisting of a vertical series of
internally and externally heated cylinders contained within a closed chamber,
gearing for rotating the cylinders, shoots or guides for transferring the material
into the cylinders, and air inlets and outlets, constructed arranged and operated
substantially as herein before described and as illustrated by the accompanying
drawings.
Dated this 20th dox of Sentember 1896.
WILLIAM E. HEYS.