U.S. patent application number 11/667720 was filed with the patent office on 2007-12-27 for rotary drum for the aerobic heating of pourable solids.
Invention is credited to Dietrich Eichler.
Application Number | 20070294910 11/667720 |
Document ID | / |
Family ID | 35744917 |
Filed Date | 2007-12-27 |
United States Patent
Application |
20070294910 |
Kind Code |
A1 |
Eichler; Dietrich |
December 27, 2007 |
Rotary Drum for the Aerobic Heating of Pourable Solids
Abstract
The invention concerns a rotary drum (1), in which the hygienic
status of separated, pourable cow manure solids (3) is modified by
aerobic heating such that the solids can be re-used as bedding in
cowsheds. The aim of the invention is that of achieving a high
charge level of the drum (1), which lies horizontally for
incorporation in an insulated container (2), with a filling level
of 60-70% being achieved. According to the invention, the loaded
solid (3) is kept in a chamber (4,8) and is passed to the drum (1)
only when there is no solid surrounding the chamber (4,8). An
important element is a flap (4,9) of the chamber (4,8), which opens
and closes in this area only. If there is solid material on the
outside of the flap, then the flap is prevented from opening
(4,9).
Inventors: |
Eichler; Dietrich;
(Grosskarolinenfeld, DE) |
Correspondence
Address: |
EDWARDS ANGELL PALMER & DODGE LLP
P.O. BOX 55874
BOSTON
MA
02205
US
|
Family ID: |
35744917 |
Appl. No.: |
11/667720 |
Filed: |
November 8, 2005 |
PCT Filed: |
November 8, 2005 |
PCT NO: |
PCT/DE05/01995 |
371 Date: |
May 14, 2007 |
Current U.S.
Class: |
34/140 |
Current CPC
Class: |
F26B 11/026
20130101 |
Class at
Publication: |
034/140 |
International
Class: |
F26B 11/06 20060101
F26B011/06 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 16, 2004 |
DE |
10 2004 051 802.5 |
May 20, 2005 |
DE |
10 2005 023 258.2 |
Claims
1. A rotary drum for aerobic heating of a pourable solid by
constantly revolving a still damp solid and supplying fresh air,
wherein the solid at the inlet side of the rotary drum enters an
antechamber through a funnel and a central opening, said
antechamber being bounded by an outer side wall and an inner side
wall located behind and spaced from the outer side wall, wherein an
inlet channel is provided between these side walls on the wall of
the rotary drum, which picks up the solid in the direction of
rotation, wherein, in the inner side wall, there is an opening
which leads to a chamber located in the interior of the drum, said
opening is covered by a flap which opens into the interior of the
drum and only opens when the chamber is in a portion of the rotary
drum wherein no pourable solid is present and closes again before
it re-enters the solid, and wherein the fresh air is sucked in
through a ring-shaped discharge weir for the pourable solids and is
sucked out through a ventilating means located in the vicinity of
the filling device and an axially arranged pipe.
2. The rotary drum according to claim 1, wherein several filler
devices for charging the pourable solid incorporating
correspondingly effective flaps are provided around the periphery
of the drum.
3. The rotary drum according to claim 1, wherein blades directly
attached to the casing of the drum advance the pourable solid
towards the discharge side whereat guide plates effective in
opposite direction are fixed at a distance of half a radius from
the casing.
4. The rotary drum according to claim 1, wherein there is a fixed
ventilation pipe located in the vicinity of the inlet side for the
solid comprising a radial pipe portion leading into the solid-free
portion of the drum, a downwardly directed elbow portion and a
succeeding axial pipe portion.
Description
[0001] The invention relates to a rotary drum in which the hygienic
status of pourable solids separated from liquid cattle manure is
modified by aerobic heating in such a manner that said solids can
be reused as bedding in cattle sheds.
[0002] The object of the invention is to obtain a high loading
factor amounting to 60-70% filling of the drum which is located
horizontally for installation in an insulated container.
[0003] In accordance with the invention, the loaded solid is kept
in a chamber and is only transferred to the drum when there is no
solid surrounding the chamber.
[0004] The crucial element is a flap of the chamber which only
opens and closes in this area. If there is any solid resting on the
outside of the flap then opening of the flap is prevented.
[0005] In order to enable ventilation to be effected despite the
filling process taking place along the axis, supply air is sucked
in through the ring-shaped weir required for the discharge of the
solid in a direction opposed to that in which the solid is being
advanced and is then sucked out through a fixed pipeline at the
inlet end.
FIELD OF APPLICATION
[0006] The subject matter of the invention is a rotary drum in
which germs can be reduced and water removed by means of an aerobic
heating process. The field of application is mainly in the
treatment of pourable solids separated from liquid cattle manure.
Hereby, the object is to modify the hygienic status of the solid in
such a way that it can be reused as bedding in cattle sheds.
TYPICAL CHARACTERISTICS OF KNOWN TECHNICAL SOLUTIONS
[0007] Rotary drums for the treatment of materials in different
ways have been known for a long time. The pourable solids are
introduced through funnels as is disclosed in specifications DE 26
34 220 C2 and U.S. Pat. No. 4,168,915. Consequently, without
special adapters in the loading area thereof, it is only possible
to fill a horizontal drum to a capacity of approximately 35% taken
with respect to the diameter of the drum.
[0008] In order to get quantities above this into the drum, it is
necessary to have blades, baffle plates and guide plates or screw
conveyers of various designs installed in the drum. A plurality of
similar built-in features are provided for this purpose in patent
specification DE 270 86 98.
[0009] In order to enable the drum to be ventilated by means of a
suction draught from the supply to the discharge side, a spiral
channel using the solid being discharged as a closure member is
arranged at the discharge side in DE-PA 199 28 883,6. This solution
requires precise dosage of the quantities being fed-in and
discharged. The drum would otherwise be either overfilled or
emptied. In this publication, the drum is accommodated in a
container. This arrangement has the advantage that the heat from
the biological process and the heated air from a drive motor can be
distributed uniformly over the outer casing of the drum.
THE OBJECT OF THE INVENTION
[0010] An object of the invention is to obtain a filling degree of
60-70% for a horizontal drum that is be installed in a container
utilising a simple device. Furthermore, just as much solid as is
being supplied to the filling side should always be automatically
leaving the drum.
[0011] The supply of air necessary for the micro-biological process
should be designed in such a way that, by using the counter-flow
principle, the treated material comes into contact with cold fresh
air whereas the material in the vicinity of the supply side comes
into contact with used warm air.
FEATURES OF THE INVENTION
[0012] According to the invention, the pourable solid that is to be
fed-in is kept in a chamber and is only delivered in that area
thereof in which no solid is present. The crucial element is a flap
provided in the chamber which opens only within the area and
closes. If any solid is resting on the outside thereof, the flap
cannot open.
[0013] For the purposes of carrying out this operation, the
pourable solid at the inlet side of the rotary drum passes through
a funnel and a central opening into an antechamber bounded by an
outer side wall of the drum and an inner side wall located behind
and spaced from the outer side wall. An inlet channel provided on
the wall of the drum and located between these walls picks up the
solid in the direction of rotation. An opening in the inner side
wall leads to a release chamber located in the interior of the
drum.
[0014] The release chamber is covered by a flap which opens into
the interior of the drum but which does not open until, due to the
rotation of the drum, the release chamber is in an area where there
is no solid present. In the course of further rotation, the flap
closes again before it re-enters the solid.
[0015] Depending on the quantity of solid that is to be introduced,
several such devices for inserting the pourable solid can be
located around the periphery of the drum.
[0016] Supply air is sucked in through a ring-shaped weir required
for the discharge of the solid in a direction opposed to that in
which the solid is being advanced. Sucking off the air is effected
through a fixed axially located pipeline which is extended radially
into the solid-free portion of the drum in the vicinity of the
filling side for the solid. A downwardly arranged elbow portion is
attached here for preventing solids from falling into the pipe. The
suction pipe is fixed to the funnel. A fan produces a negative
pressure required for the movement of the air.
EXEMPLARY EMBODIMENT
[0017] FIG. 1 shows a longitudinal section through a rotary drum
(1) which is installed in an insulated container (2). Goods to be
treated (3) are introduced into the interior of the rotary drum (1)
through a filling device (4). The rotary drum (1) is set into
rotation by a drive (5). The pourable solid (6) is constantly moved
toward the discharge side by blades (7) attached to the surface of
the drum. Guide plates (8) effective in opposite direction are
located in the vicinity of the discharge side and are fixed at a
distance of approximately half a radius from the surface of the
drum. They dam up the solid in front of the ring-shaped discharge
weir (9). In consequence, a large portion of the drum volume
remains filled with 65-75% solid. Only that much solid as is
supplied by way of the filling device (4) is discharged from the
drum through the discharge weir (9).
[0018] The air flowing through the discharge weir (9) in a
direction counter to that of the flow of the solid, over the
filling volume (6), is sucked out of the system by means of a fan
(13) through a fixed ventilation pipe (11) and the following axial
pipe (12). If necessary, a filter system corresponding to the state
of the art can be connected here at the outlet side thereof.
[0019] FIG. 2 is an axial section of the drum (1) showing the
filling device (4) at the intake side and the positions of the
sections A-A and B-B shown in the following figures. The damp solid
that is to be composted passes through the funnel (4.1) and the
central opening (4.2) and enters the antechamber (4.3) which is
formed by the face wall (4.4) and the inner side wall (4.5).
[0020] In this embodiment, two oppositely located identical filler
systems are provided for feeding purposes.
[0021] During rotation of the drum, the pourable solid is picked up
by the inlet channel (4.6) that is open in the direction of
rotation, and is carried into the rear portion of this channel
during further rotation of the drum. Here, there is an opening
(4.7) in the inner side wall (4.5) through which the solid enters
the release chamber (4.8) in the course of further rotation.
[0022] At the appropriate side thereof, this chamber has a flap
(4.9) which will only open when the chamber reaches that portion of
the drum in which no solid is present so that the flap can only
open here. A further condition for the position of the flap (4.9)
is that it closes before it re-enters the solid and remains closed
whilst in the solid.
[0023] For the purposes of a better overview, the reference symbols
are only provided at a few locations of the following figures.
[0024] FIGS. 3, 4 and 5 show the section A-A through the
antechamber (4) illustrated in FIG. 1. The drum is rotated through
approximately 33.degree. in FIG. 4 and through a further 45.degree.
in FIG. 5. In FIG. 3, the solid begins to flow into the inlet
channel (4.6) in the lower filler device. In the upper filler
device, the process of emptying the channel through the opening
(4.7) is already completed. In FIG. 4, the process of filling the
inlet channel (4.6) is almost completed and the solid is already
entering the release chamber (4.8) represented by dashed lines
through the opening (4.7) in the inner side wall (4.5). In FIG. 5,
just so much solid as the release chamber (4.8) can accommodate now
slides through the opening (4.7) from the inlet channel (4.6).
[0025] FIGS. 6, 7 and 8 show the section B-B represented in FIG. 2.
Hereby, the drum is likewise rotated through approximately
33.degree. in FIG. 7 and through a further 45.degree. in FIG. 8. In
FIG. 6, the flap (4.9) of the release chamber (4.8) of the now
upwardly located filler device has just opened and the solid has
slid down into the drum. The flap of the filler device in the lower
position is held in a closed position by the solid abutting the
flap.
[0026] In FIG. 7, the flap (4.9) of the filler device now located
in the upper position has reached its largest opening angle and
then begins to close again under its own dead weight. In FIG. 8,
the outpouring solid begins to cover the already closed flap (4.9).
In the oppositely located filler device, the associated flap would
open under its own dead weight if there were no solid in the drum.
However, it cannot open up because the still immoveable solid is
preventing this action. In consequence, its contents are carried
into the area in which the flap can reopen due to the flow-off of
the solid thereby enabling 60-70% filling of the drum.
[0027] In this figure furthermore, the fixed ventilation pipe (11)
is shown together with its elbow portion which leads away from the
solid-free part of the drum.
* * * * *