Improvements in Apparatus for Drying Granular, Pulverulent, and like Materials.
Year: 1891

page_text: Date of Application, 8th Dec., 1891-Accepted, 12th Mar., 1892
COMI LEIE DIUINICATION.
Improvements in Apparatus for Drying Granular, Pulverulent, and
like Materials.
I, MAX HECKING of the City of Dortmund in the Kingdom of Prussia,
Mechanical Engineer, 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 :-
In order to obtain in a small space both a larger heating surface and a lengthy
course for the substances to traverse, a second rotating heating drum of annular
section is placed inside the actual fixed heating drum.
The invention is shown on the annexed sheet of drawings, on which
Figure 1 is a longitudinal section of a stove constructed according to this
invention;
Figure 2 is a section on line A-B of Figure 1, while
Figure 3 is a section corresponding to Figure 2, but of a modification.
The larger drum or cylinder is heated externally by means of steam or furnace
gases, it may also, as shown on the drawing, be of a trough-shaped section m and
have a cover D fitted on to it.
The inner drum t is of annular section and is fixed by means of the trunnions z z¹
in such a way that steam or hot air may enter through these latter.
The inner drum has an orifice o into which at each revolution a given quantity
of the material to be dried is conveyed from a charging hopper f. Longitudinal
ridges s which are fixed in the inside, lift the material to be dried and allow it to
fall down again at a suitable height.
The drum is conical in shape so that the material to be dried is conveyed forward
towards the widened end where it is seized by the scoops s' attached to the outer
side of the drum and in consequence of the outer surface being also conical in form
is conveyed back to the exit a. The naves carrying the axles of the drum are
made in the form of a cross in order to allow of openings at 1 for admitting the air
and at for allowing the dried material to pass out. is a chimney for the exit of
the steam developed, d and d' inlet and outlet nozzles for the heating medium of
the outer drum.
The inner drum may be composed of a number of tubes placed closely side by
side in the manner shown in Figure 3, whereby the heating surface of this drum ís
considerably increased both on the outside as well as the inside.
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 t
1. The improvements in drying stoves or apparatus consisting in constructing
the same of two concentrically arranged drums, one of which may be trough-
shaped, but the inner one of which has an annular section, for the purpose of
conveying the material to be dried backwards and forwards, or for utilizing the
outer and inner heating surfaces of the same, substantially as hereinbefore described
and shown.
2. In cylindrical drying stoves or apparatus, the employment of a conical form
of inner drum for the purpose of carrying forward the material to be dried on the
inner and outer surfaces, substantially as hereinbefore described and shown.
3. The modified construction of inner drum Z consisting in forming the same of

page_text: tubes placed closely side by side in the manner shown in Fig. 3 for increasing the
heating surface.
Dated this 7th day of December 1891.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.