Improved Process and Apparatus for Treating by Centrifugal Force, Drying, Impregnating and Moulding Plastic Materials.
Year: 1899

page_text: Date of Application, 10th Aug., 1899-Accepted, 10th Aug., 1900
Improved Process and Apparatus for Treating by Centrifugal Force,
Drying, Impregnating and Moulding Plastic Materials.
We, RICHARD LANDMANN, of 14, Lessingstrasse, Leipsic, Merchant, and
NICOLAUS REIF, 5, Eden Strasse, Hanover, Engineer, both in the Empire of Ger-
many, 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:-
The object of the present application consists of a process and apparatus for
subjecting to centrifugal pressure, drying, and impregnating various substances
in order to produce therefrom plastic materials
In the following description the application of the process to peat is especially
kept in view.
The processes hitherto published relating to peat and of similar title to the
above have hitherto left even the very moderate requirements of the briquette
manufacturer unsatisfied, because on the one hand the requirements of a quick
method of drying within a small space possible at all times and not too expen-
sive, and of a cheap method of compressing which will afford sufficient power
of resistance to atmospheric influences, and in a certain sense also to disin-
tegration by fire,. have been left unsolved. On the other hand, however, in spite
of the fact that the necessary capital outlay is very great in comparison to the
period of work, which can only be a few months in each year, and the low
selling value of the product, efforts have been made to produce such plastic mate-
rials in artistic forms. The hitherto known processes have, however, extended
only to efforts to press or cast figures out of a cold or heated mixture consisting
of a paste of peat with water and some adhesive; or to impregnate objects
pressed out of dry peat with solutions of adhesive materials. But owing to the
hygroscopic qualities of the peat, by processes of the first kind, besides the diffi-
culty of drying, there are only produced shapeless and damaged specimens. The
second process rests upon a fallacy because compressed peat can obviously be only
coated very superficially with the fluid cement, unless it absorbs the moisture
into the interior. If, however, the fluid penetrates the interior the very hygro-
scopic peat becomes pasty and alters its shape, and thereby we arrive again at
the first process.
These processes have consequently found no practical application, the more
as in addition to the difficulties above set forth it was found necessary to change
the peat chemically, or to add certain necessary substances for the production
of cement, and the impregnating of the peat in a simple manner, so that the
pressed peat on leaving the stamps or rolls should form an absolutely fully pre-
pared and satisfactory product of high resisting power and of an appearance
similar to wood or stone. The removal of the above indicated difficulties and the
production of an article having the above set forth qualities is the object of the

page_text: invention about to be described, which is carried into practice by the aid of the
machines also herein set forth.
Referring to the accompanying drawing the apparatus for carrying out the
process is illustrated as follows:--
Figure 1 shews a centrifugal apparatus partially in section.
Figure 2 shews another centrifugal apparatus in elevation and ground plan.
Figure 3 shews a detail of the apparatus partially in section.
Fluid peat as it comes from the bog is brought by means of a hopper a
(Figure 2) into the starshaped centrifugal b, the opposing walls whereof consist
of Hat iron plates over-lapping one another in the form of scales, and so that
between them exist a series of slots c.
As the centrifugal force impels the fluid peat outwards through the channels
formed in this manner in the walls and narrowed towards the periphery, there
exists in consequence of this narrowing a strong pressure upon the contents in
the channels, and this causes the separation of a portion of the water contained
in the material, which water escapes through the slots c and runs off through the
pipes e.
As the slots c are placed in the direction of the motion of the contents thereof,
the stopping up of the same, as often happens in the case of the usual perforated
tin plate walls is rendered impossible.
The apparatus consequently presses and cleanses the wet peat; and stones,
roots, and so forth, owing to the fluid condition of the peat, sink to the bottom
and remain in the apparatus, and may be removed by mean of an aperture in
the bottom. The slot is not carried to the bottom of centrifugal b, and the
ledge 62 prevents the small stones, roots and so forth from escaping while the
larger stones and roots cannot pass through said slot. It should here be noticed
that the wet peat is continuously supplied and discharged. The partially pre-
pared peat then passes through a hopper and openings f into a second centri-
fugal (Figure 1) which is formed of conical rings h engaging one within the
other, in the manner of scales and of the plate i. Its shaft s is driven by the
pulley 18 and supported in the collar bearing which is connected by arms
and screws with masonry; or if the apparatus is transportable, with suitable
columns or pillars.
g
Between the plate i connected with the shafts and the periphery of the centri-
fugal is formed an outlet for the peat. The centrifugal force exercises in this
apparatus g a great pressure upon its contents, whereby a further expressing of the
moisture and partial drying takes place. The water expressed escapes through
the slots a, is thrown against the cover p, and removed by the tube p
In order to delay the exit from the centrifugal y and to prolong the separa-
tion of moisture as much as desirable there is provided an apparatus for periodi-
cally closing the outlet slot. In the drawing one half of this device is illustrated
in section in connection with a closed slot, and the other in elevation in connee-
tion with an open slot.
Upon the boss of the plate i there slides a ring y¹ connected by arms with the
closing ring y. The ring y rests upon the ring which is provided with rollers
and supported on the bearing k, so that it can be raised by means of the lever l
revoluble around the pivot m.
In order to cause the automatic closing, there is placed on a rod connected
to the lever a weight 14 which raises the ring y. If now the revolving cam 13
raises the weight 14 by means of the rollers 12, the ring y sinks and rises again
when the cam 13 is out of contact with the roller 12. The peat having been freed
from water as far as possible is broken up against the perforated wall 24, and
is passed through the hopper 1 into the drying space, where the funnel shaped
revolving plate 6 receives it. It then passes through the drying chamber, being
constantly thrown back upwards by means of the plates 6, 7, and S. This
progress takes place with considerable delays and with constant alterations of its
shape in the direction indicated on the drawing by the arrow, and with constant

page_text: raising into the dry air of the chamber, and constantly offering fresh surfaces
to the action of the air. It finally passes through the funnel 4 to the outlet 15.
The flap 20 attached to the plate 10 prevents any accumulation of the falling peat.
The hoppers 2 and 3 are perforated in order to give access to the ascending dry air.
The drying process can of course be prolonged by multiplication of the hoppers
and revolving plates.
The drying chamber is preferably constructed of the double walled iron plate
cylinder 11, into the outer case of which tube u leads. The hot gases passing
in through this tube and obtained from the boiler flue heat the drying space in
its upper parts where the peat is wettest by means of radiation, and gradually
cool and pass in the direction indicated on the drawing by the arrows through
the openings 5 to meet the peat, and finally when fully charged with water
vapour escape through an annular opening into a flue connected with the
chimney. by means of the outlet 15 which can be closed by a damper 17 the peat
passes into a 'kneading device or press 21, in which there revolves a shaft pro-
vided with screw propellers 22 by means of which the peat is pressed and forced
out through the orifice 23 in the form of a cake and can then be cut into bricks
or carried further to rollers.
If it is desired to prepare articles of small value such as briquettes the tem-
perature in the lower parts of the drying space is so regulated that the empy-
reumatic constituents of the peat are developed, and a certain amount of cohesion
is obtained thereby. If, however, it is intended to impregnate the peat with
other materials and to have cementing materials such as rosin, cements, and so
forth equally distributed throughout, this can be attained in the following
manner:-
In the box t which is heated by the waste gases, the necessary substances are
placed and discharged in the form of powder or of liquid through the tube w to
the centrifugal plate 10, and are thrown by this in the direction indicated on
the drawing by an arrow amongst the peat coming from the plate & and are
carried forward together with this peat, thereby entering or covering its particles.
In order to regulate the quantity to be supplied there is provided on the one
hand a ball valve adjustable by means of a hand wheel v, and on the other hand
a plate 9 which is connected by the bolts 25 with the ring 26, and can be
adjusted together with this latter whereby the exit slots existing between the
plates 9 and 10 can be adjusted.
According to the nature of the substances thus added it will be necessary
either to melt the same for the purpose of binding the peat, and to bring all por-
tions of the mixture to an equally high temperature before or during the press-
ing, or else to add to the mass a solvent of the substances in such quantity and
so distributed that the same become chemically bound without excess and conse-
quently any injurious drying of the pressed articles is no longer necessary.
In addition to the troublesomeness and other drawbacks of the wellknown
application of moulds heated from the outside these moulds when used with many
substances, and especially with a substance which is so bad a conductor of heat
as peat, especially in the case of large pieces, will produce an article which is
only cemented at the surface. It is preferable, therefore, in the present process
to make use of gases heated air or of a solvent in the state of vapour and to pass
this itself into the mass. For this purpose the distributor shewn in Figure 3 is
made use of in the case of large moulds, either in these moulds themselves or
placed in the hinder part of the kneading apparatus in which the mass is still
tolerably loose.
By means of the annular projections 28 in the casing 27 annular channels 29
are formed which run in the direction of motion of the mass and are consequently
not liable to be stopped up. These channels are connected with the steam
supply tube 16 through the tube 30. The mass propelled in the direction of the
arrow shewn in Figure 3 by means of the propeller placed in the hinder and
narrower part of the kneading cylinder is surrounded with steam escaping from

page_text: the annular channels 29 and penetrated thereby, and the mass pushed forward
by the blades of the propeller in the front part of the mixing cylinder in the
direction shewn by the arrow in Figure 3 is surrounded by the steam escaping
through the annular channels 29 and penetrated thereby and is then kneaded by
the blades in the front part of the mixing cylinder. It is thereby condensed and
finally passed through the orifice 23 in the presses or moulds in order to proceed
therefrom as the finished product.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. Process for the centrifugal or other drying, and impregnating of various
materials and the further preparation thereof for plastic purposes characterized
by the arrangement 'that the material to be operated is prepared by separating
it from stones roots and the like, with subsequent expression of water by means
of centrifugal force with continuous access and exit of the material and is then
subjected to further application of centrifugal force and to a progressive drying
whereby the material with constant alteration of form and position is moved
towards the exit in such a manner that the drying currents passing in the opposite
direction come into intimate contact with the goods to be dried, and at the same
time there is obtained an intimate mixture of any binding or impregnating
material also introduced by centrifugal force in the opposite direction to that of
the material.
2. A modification of the process set forth in Claim 1 characterized by the
arrangement that the material so prepared is subjected to or concentrated by
the action of gases, hot air or solvent in the gaseous form before and during the
assumption of its ultimate shape or is sufficiently concentrated in a mixing or
kneading apparatus or a press.
3. For the purpose of carrying out the process according to Claim 1, a centri-
fugal apparatus for pressing out the water separating foreign bodies, and drying
the material, to be further treated, characterized by the arrangement that the
expressed fluid driven out by the centrifugals in the drying process is passed
through outlets c which are placed in the course of the contents of the centri-
fugal, whilst the material is constantly removed 'through passages narrowing
towards the periphery and thereby experiences a considerable pressure, and a
closing of the exits for the further prolongation of the preliminary process is
effected independently by means of an adjustable ring y by aid of a rotating
cam 13 operated in connection with a shaft and rod r l.
4. For carrying into effect the process set forth in Claim 1, a centrifugal device
for the further treatment of the material in which the latter is repeatedly con-
ducted over conical revolving plates 6, 7 8 separated by perforated walls 1, 2,
3 placed parallel to one another and lying in a sloping direction, said plates
effecting a throwing forward and deformation and elevation of the material,
whereby a more effective action of the current of dry air passing through in the
opposite direction can result.
5. In carrying into effect the process set forth in Claim 1 an apparatus for the
introduction of liquid or powdery impregnating or binding material characterized
by the arrangement that this material passes from a container properly heated
by the drying current to the lowermost funnel shaped revolving plate 10 and
is thrown by it amongst the dry material cutting or surrounding the particles
thereof so that the regulation of the admission of the material in question can
take place by means of an adjustable cover placed opposite the revolving plate 10
forming an adjustable outlet.
6. In the carrying out of the process set forth in Claims 1 and 2 a kneading
device or press characterized by an annular channel 29 placed therein and formed
of plates lying over one another like scales in the direction of movement of the
material, which channels admit in combination with a pipe 16 and connecting

page_text: pipe 30 hot air or gaseous solvent, to the material, in order in
this manner to effect the direct melting or solution of the impregnating
or binding material during the assumption of the ultimate form.
Dated this 10th day of' August 1899.
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicant.