Note: Descriptions are shown in the official language in which they were submitted.
37~
This invention relates to a process and an apparatus
for the mechanical detouring of peat More particularly, the
invention is directed to the progressive compression of peat
for a certain distance, such as about six feet, by allowing
two conveyors to converge towards one another. One of the
conveyors may carry molds to contain raw peat while the other
has pressure elements, both working in pairs.
There is presently a marked interest to use peat
as a binding agent for poulticing iron ore, as a substitute
for bentenite. Although this latter mentioned material gives
pellets of excellent quality, it is a substance which is
expensive mainly because it is only available from specific
areas of the world, such as the state of Wyoming in the
U.S.A. and Greece. Furthermore, it contains silica which
has the disadvantage of mixing with the iron ore when
preparing the pellets. Tests made with peat have given
good results and as long as a good supply can be found
it is only necessary to give it a suitable treatment to
make it readily acceptable as a binder.
When carrying out tests with peat it was found
that shredded peat containing between about 70 - OWE water,
preferably 72%, was highly suitable as a binder. Since the
deposits of peat always contain a large amount of water and
because this amount is not consistent, there is a need for
an apparatus which can debater peat on a continuous basis
and to a specific degree of humidity
any forms of mechanical detouring have been
disclosed in the prior art: roll and belt presses, filter
presses, screw presses, centrifuges and screens. High
pressure is required to reduce the water to a level of
about OWE. An optimum combination of high capacity and
pressure is therefore needed.
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I
'row well known presses are the Ingersoll-Rand
Vari-NipTM press and the Solacer Belt Press. Both can
reduce water content to the 65%-70/~ level.
The Vari-Nip press consists of two horizontal
rolls mounted in a sealed vat. One roll is fixed, and
the other is movable to allow for variable nip openings.
If the mat thickness varies, the variable roll automatically-
lye follows this change and maintains a constant nip load,
resulting in a constant discharge of solids.
The slurry, at an incoming solids concentration
of approximately 3% to 5%, enters the sealed vat at a
pressure of approximately 3 to 5 prig. The slurry then
drains by pressure filtration and forms a mat on the roll
surfaces, which is carried forward into the nip by the
rotation of the rolls. In the nip, the mat is further
detoured to the desired dryness of up to OWE solids.
Immediately beyond the nip, the solids are scraped
off the rolls and guided into a top-mounted, screw-type
shredder conveyor. The detoured material is then gravity-
discharged at the rear end of the machine for ultimate disposal. The priest flows through the roll faces and is
discharged at the bottom of the press.
In the Solacer "multi-nip" press, the peat is moved
through the machine on belts. The press has a large number
of pairs of rollers, which apply progressively increasing
pressure as the peat passes through the machine. In the
inlet zone the peat is stabilized by application of moderate
pressures. This feature minimizes rejection of the peat at
the nip of the rolls In the later stages, higher pressures
(approximately 600 psi) are applied to maximize the extract-
ion of water from the stabilized "cake" of peat.
The belt system consists of a total of four belts.
-- 2 --
Two are polyester sieves between which the peat travels
through the machine. Above the upper sieve belt is a
resilient rubber belt, a key element in stabilizing the
peat in the pressing zone, which allows for foreign
material that might find its way into the press with the
feed. Below the lower sieve belt is a harder rubber belt
provided with diagonal channels on a herringbone pattern,
through which the water is expelled. Both presses are
expensive and complicated to operate.
According to the present invention, there is
provided an apparatus for the mechanical detouring of peat
to a predetermined degree of humidity which comprises con-
voyeur means, means for continuously feeding peat to the
conveyor means' pressure means engage able with the conveyor
means when the latter are subjected to continuous circular
lion, means enabling the pressure means to cause the peat to
undergo a gradual increase of pressure while it travels along
an initial part of the conveyor means to thereby remove water
from the peat' means for gradually decreasing the pressure
while the peat travels along a remaining part of the conveyor
means, means for continuously removing peat dried to the pro-
determined degree from the conveyor means; and means for
collecting the dried peat.
Preferably, there are provided means for keeping
the peat at a constant pressure at the end of said gradual
increase of pressure and before decreasing the pressure.
The conveyor means preferably comprises a chain
of receptacles.
According to the invention, there is also provided
a process which comprises providing a continuous circulation
of receptacles on a conveyor, continuously feeding raw peat
to the receptacles, subjecting peat contained in the
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receptacles to a gradual increase of pressure along an
initial part of the conveyor, gradually decreasing the
pressure while the peat travels along a remaining part
of the conveyor, continuously removing peat dried to the
predetermined degree of humidity from said conveyor, and
collecting the dried peat.
Preferably, there is an intermediate step after
the gradual increase of pressure and before decreasing the
pressure, during which peat is kept at a constant pressure.
The invention will now be illustrated by means
of the annexed drawings which are only given for the purpose
of illustration and are not intended to be limiting.
In the drawings:
EGO. 1 is an elevation view of an apparatus for
detouring peat according to the invention,
FIG, 2 is a view taken along line 2-2 of Fig l;
FIG. 3 is a view in elevation showing the feeding
as well as the first stage of drying of the same apparatus
FIG. 4 is a view in elevation showing the last
stages of drying as well as the peat collector of the
same apparatus,
FIG. 5 is a view showing the pressure members in
pressing position while fully engaged in the receptacles
of the lower conveyor,
FIG. 6 is a view taken along line 6-6 of FIG 5,
FIG. 7 is a view taken along line 7-7 of FIG. 1,
FIG. is an end view of a mold receptacle,
FIG. 9 is a side view of the same mold, and
FIG. 10 is a partial view taken along line 10-10
of FIG. 9,
Foxily and 12 show alternatives for the receptacles.
~797~
The second sheet of drawings contains FOX, 8, 9, 10,
11 and 12.
Referring to the drawings, there is shown a peat
press 1 which is mounted on a trailer 3. The press 1,
which is an apparatus for the mechanical detouring of
peat to a predetermined degree of humidity, essentially
consists of a feeder 5, a lower conveyor 7, an upper con-
voyeur 9, a peat collector 11, the whole being mounted on
a frame 13.
The frame 13 can be designed in any manner which
is suitable to mount the two conveyors 7 and 9 as well as
the feeder 5 and the collector 11. In the model which has
been illustrated, it merely consists of a pair of Beams
15, 17, which are disposed over a plurality of transverse
I-beams 19, all as particularly shown in Fig. 1 of the
drawings. The transverse beams 19 sit on corresponding
bases 21 which rest on the trailer 3.
As illustrated, the rear end of the trailer 3 is
the forward end of the apparatus 1 and the front end of the
trailer constitutes the rear end of the apparatus 1. At
the front end of the apparatus 1, there is a sprocket wheel
23 which is mounted on a suitable shaft 25 while at the
rear end of the apparatus there is a sprocket wheel 27
which is mounted on a corresponding shaft 29. A sprocket
chain 31 carrying receptacles 33, which will be described
more fully hereinafter, is rotatable mounted around both
sprocket wheels 23 and 27. It should be noted that while
the sprocket wheel 23 is freely rotatable around its shaft
25, the sprocket wheel 27 is, on the other hand, operatively
connected to a motor (not shown in the drunks In opera-
-- 5 --
I I
lion, the motor will cause rotation of the sprocket chain around both sprocket wheels 23 and 27.
As shown in FOX and 7, over the pair of I-beams
15, 17, which are mounted in parallel fashion and extend sub-
staunchly along the entire length of the apparatus, there
are a series of staggered roller bearings 35, 379 which
are mounted over each lower I-beam. It will be noted that
a roller bearing 35, which is mounted on one I-beam,
corresponds to a roller bearing 37, which is mounted on the
other lower I-beam. These roller bearings are staggered-
lye arranged and are mounted on the beams 15, 17, in a manner
known to those skilled in the art. Each pair of bearings 35,
37, receives a roller 39, and because of the staggered
arrangement of the roller bearings, the rollers are staggeredly
arranged on the frame constituted by the I-beams 15, 17.
As shown, the staggeredly mounted rollers 39 are
evenly distributed along the entire length of the frame so
as to constitute a support for the receptacle containing
sprocket chain 31. The staggered arrangement of the
rotatable rollers 39 enables to maintain a constant and
non-pulsating pressure in the sprocket chain 31 as the
latter rotates along the frame, around both sprocket wheels
23, 27.
For a better description of the receptacles 33,
and the mounting thereof on the sprocket chain 31, refer-
once is made to Figs. 4 and 6 to 10 inclusive. As shown,
each receptacle 33 comprises two vertical sides 41, 43,
which are parallel to each other, and a bottom 45 which
connects the two sides 41, 43, in the particular manner
shown in Fig. 6 of the drawings. Preferably, the bottom
45 is welded to the sides 41, 43. Also as shown 9 the
bottom 45 is provided with perforations 47 to permit water
I
to escape from the receptacle 33 when the peat is under
pressure as will be discussed later. Each perforation 47
has a first portion 49 of smaller cross-section followed by
a second portion 51 of larger cross-section. This particular
arrangement is intended to prevent the peat from escaping
through the perforations.
Returning to the two sides 41, 43, each has a
downward extension 53, 55 past the bottom 45, thereby
defining parallel flanges. Bolts 57, 59, are disposed, as
shown in the bottom 45, for mounting the receptacle on the
chain 31 as will now be explained. AS shown in Fig. 6,
the receptacle 33 sits over the sprocket chain 31 by means
of its flanges 53, 55, and the receptacles 33 are attached
to the chain by means of the bolts 57, 59. For this
purpose, the bolts 57, 59 extend through links 61 of the
sprocket chain 31 and are screwed tightly thereon by means
of nuts 63, 65.
In the embodiment illustrated, the sides 41, 43,
have been shown with perforations 67 which are identical
to perforations 47 provided in the bottom 45 of the
receptacle 33. However, in most cases, it has been found
that the perforations 67 in the sides 41, 43, are not
necessary and, therefore, it may be completely satisfactory
to have receptacles wherein the perforations are only provided
in the bottom 45.
Turning now to the second conveyor 9, there are
provided sprocket wheels 69 and 71 which are respectively
mounted at both. ends of the frame 1, at a higher level than
the sprocket wheels 23 and 27. In the case of conveyor 9,
both sprocket wheels 69, 71 are freely rotatable. A sprocket
chain 73 is rotatable mounted around both sprocket wheels 69,
71 in the particular manner shown in Figs. 3 and 4 of the
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drawings, and a series of pressure members 75 are attached
in a manner which will be described later to the sprocket
chain 73.
It was mentioned above that the idea of the invention
is to create an increasing pressure on the peat as it advances
on the lower conveyor, optionally followed by a treatment at
constant pressure, and, finally, by a period wherein the
pressure of the peat is gradually decreased. This is made
possible by causing the chain 73 to first of all gradually
approach sprocket chain 31 followed by a stage wherein the
sprocket chain 73 causes the pressure in the receptacle 33
to be constant for a certain distance along the conveyor
31; after which the pressure is gradually decreased by
allowing the sprocket chain 73 to gradually move away from
the sprocket chain 31. For this purpose, the chain 73 is
guided by three guides 77, 79 and 81. Referring to Fig. 3,
it will be seen that guide 77, which is in the form of an
I-beam, is adjustable connected to guide 79 to be downwardly
inclinable in order to gradually bring the sprocket chain 73
from the sprocket wheel 69 closer to the first sprocket
chain 31, thereby, as a result of the contact of the two
conveyors 7 and 9, inducing rotation of the sprocket chain
73 and enabling the pressure members 75 to penetrate deeper
and deeper into the receptacles 33, as particularly shown
in Figs. 6 and 7 of the drawings, to gradually increase the
pressure of the peat contained in the receptacles 33. The
guide 79 is nearly horizontal and is mounted to provide a
very slowly decreasing distance between the sprocket chain
31 and the sprocket chain 73, consequently causing such a
perpetration of the pressure members 75 in the receptacles 33
as to keep the peat under constant pressure while the platter
is traveling underneath the guide 79. Finally there is a
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guide 81 which is connected to the guide 79 to be upwardly
inclinable in order to gradually bring the sprocket chain 73
further away from the sprocket chain 31 until the sprocket
chain 73 reaches the sprocket wheel 71. This will cause the
pressure members 75 to penetrate less and less into
receptacles 33, thereby gradually decreasing the pressure
of the peat contained in the receptacles. It will be
noted that the connection between the guides 77, 79 and 81
does not form part of the invention and can be carried out
in any manner known to those skilled in the art. The way
shown in the drawings is only for illustrative purposes
Of course, the chain 73 cannot be allowed to slide
along the guides 77, 79, 81, per so. Suitable sliding means
must be provided end in the embodiment illustrated, this is
made possible by using transverse rollers 83. These rollers
are held by the guides 77~ 79 and 819 as shown in the draw-
ins and as will be explained in more detail hereinafter.
For the time being, it is merely sufficient to mention that
the chain 73 rests against the rotatable rollers 83 and that
the latter are staggeredly arranged to maintain a constant
and non-pulsating pressure in the chain 73.
It was mentioned above that the guides 77 and 81
are adjustable with respect to the guide 79. This is
essential in order to be able to vary the angles of incline-
lion of the guides 77, 79, depending on the nature of the
peat to be detoured, especially if the water content of
the raw peat varies to a large extent.
Returning to the upper conveyor 9, we shall now
describe the pressure members 75 in greater detail. Each
pressure member 75 comprises a base plate 85, a holding
plate 87 which is spaced from the base plate 85 and is
parallel thereto, and two side plates 89, 91, which are
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joined together by means of the base plate 85 and the hold-
in plate 87, all as shown in FIG. 6 of the drawings. The
pressure member 75 is obviously shaped to sit substantially
exactly in the receptacle 33. It will be noted that the lower
edges of the side plates 89, 91, are pointed as at 93, 95,
in order to prevent peat from accumulating between the
sides 41, 43, of the receptacle 33 and the side plates 89,
91, of the pressure member 85. The two side plates 89, 91,
each have an upward extension 97, 99, past the holding
plate 87, to define parallel flanges. It will be noted
that bullet, 103 are provided in the holding plate 87
for connection of the pressure member 75 to the sprocket
chain 73. For this purpose, the sprocket chain 73 is
disposed above the pressure members US between the flanges
defined by the extensions 97, 9g, and the pressure members
are attached to links 105 of the sprocket chain 73 by means
of nuts 107, 109, screwed onto the bolts 101, 103.
It has been pointed out before, that the sprocket
chain 73 is allowed to slide along the guides 77, 79 and 81
by means of the rollers 83. Before further describing the
arrangement of the rollers, it should first of all be
pointed out that, as in the case o-f the lower I-beams 15~
17, the guides 77, 79 and 81 also appear as pairs of I-beams
which are parallel to one another. Underneath each pair of
I-beams 77, 79 and 81, there is a series of staggeredly
arranged roller bearings 111, 113, so that a roller bearing
111 underneath one specific I-beam 77, 79 or 81, corresponds
to another roller bearing 113 which is disposed underneath
the other parallel upper I-beam 77, 79 or 81 of a specific
pair. As the rollers 83 are mounted in the roller bearings
111, 113, in known manner, there is provided a staggered
arrangement of the rollers 83 on the upper I-beams 77, 79
-- 10 --
iota
or 81, which will make sure that there will be constant and
non-pulsating pressure in the chain 73.
The mounting of the guides 77, 79 and 81 on the
frame will now be described. A number of transverse members
19 are disposed underneath the lower I-beams 15, 17, to
maintain the latter mentioned I-beams in horizontal post-
lion. In other words, the parallel longitudinal beams
15, 17 rest on a plurality of I-beams 19. Bases 21, as
mentioned above, are provided on the frame to mount the
transverse members 19. A number of additional transverse
members 115 are disposed above each pair of upper I-bearns
77, 79 and 81 in the particular manner shown in Fig. 1 of
the drawings. As shown, some of the transverse members 19 are
connected to corresponding transverse members 115 by means
of holding rods 117. Preferably, there is a first pair of
holding rods to hold the first pair of downwardly inclinable
I-beams 77, there is a plurality of holding rods 117 to hold
the second pair of horizontal I-beams 79, and there is a
last pair of holding rods 117 to hold the third pair of
upwardly inclinable I-beams 81.
In order to make sure that the upper turn of the
sprocket chain 73 remains horizontal without touching the
upper ends of some of the holding rods 117 and the guides
77, 79 and 81, a roller 119 is mounted in known
manner between the upper end of the first pair of holding
rods 117 and a second roller 121 is mounted between the
upper ends of the last pair of holding rods 117. As shown,
these two rollers 119, 121, will be used to support the
sprocket chain 73 during its return pass.
As mentioned above, feeding of the apparatus
according to the invention is carried out by means of a
hopper 5, of known construction, into which peat is loaded
-- 11 --
3LZ17~7~
for filling the receptacles 33 as they pass underneath the
hopper 5. The collector 11 is made of a hood 123 and an
impeller 125 which is operatively connected to a driving means
(not shown) so as to remove the peat dried to a predetermined
degree and throw it to a suitable container trot shown).
Preferably, the pressure members 75 are made
of two identical steel blocks which are welded side to
side, as shown in Fig. I
In order to make sure that the pressure remains
constant while the lower conveyor passes underneath the
guide 79, the distance between the upper and the lower roller
increases at the rate of I inch on a distance of 12 feet.
The preferred distance between the perforations
to make sure that there is a satisfactory escape of water
is between 1/2 to 1 inch, or less than 1 inch.
The operation of the device is of course self-
understood. It is merely sufficient to mention that the
motor is operated to drive the sprocket wheel 27 so that
the lower conveyor moves in the direction indicated by
the arrow 133. As the upper conveyor becomes closer to the
lower conveyor, the upper conveyor will be moved along by
the action of the lower conveyor.
The peat which is filled into the receptacles 33
is gradually pressed by the pressure members 75 until it
is discharged from the apparatus by moans of the impeller
125.
The perforations 47, can also be in the form of conic
eel holes not shown in the drawings alternatively, with role-
fence to FIGURES 11 and 12, there may be provided tapered slots
127 which permit the evacuation of water. In addition the both
Tom 45 may be covered with a screen 129 to prevent small part-
ales from escaping through the perforation or through the
- 12 -
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tapered slots.
Other rollers 131 may also be associated with rods
117 to further help in keeping the chain 73 horizontal.
