[0001] The present invention refers to a method and a device for treating such, comparatively
solid waste that accompanies waste water, which for purification flows through a chute
or the like to a purification plant.
Background of the invention
[0002] It is earlier known by means of elements projecting down into such a chute to catch
solid waste and to transport it from the chute, which waste is thereupon subjected
to a pressing operation for removal of the water The residual products that have been
pressed out often contain fæces, which results in that these waste products are very
nasty-smelling, bacterious and unpleasant to handle.
Purpose and most essential features of the invention
[0003] The purpose of the invention is therefore first to remedy these inconveniences and
to provide an automatic process for treatment of waste of the above mentioned type
in such a manner that the solid waste as far as possible can leave the plant for further
destruction or for other treatment, whereas the biologically destructable products
may be brought back to the waste water. These tasks have been solved in that said
waste is conveyed up form the chute or the like and into a compacting and dewatering
plant, where it is at one hand compressed while giving off liquid and on the other
hand is washed out in that water under high pressure is forced through it, whereby
the liquid and the washing water are preferably brought back to the chute for purification,
while the compacted waste is shaped into cakes, briquettes or the like, and is fed
out from the plant.
[0004] The invention also refers to a device for accomplishing the method and having the
features defined in claim 4.
Description of the drawings
[0005] In the accompanying drawings is shown an embodiment as an example of the invention,
whereby the drawings schematically show a plant for treatment of the waste transported
in the manner mentioned above and where the different drawing figures illustrate different
steps of the treatment process.
Fig. 1 thereby shows schematically and partially in section a plant according to the
invention in a ready position,
Fig. 2 shows the same plant but in a treatment step, where a certain compression of
the waste has been made and where water under high pressure is forced through it,
Fig. 3 shows the plant according to Fig. 1 and Fig. 2 but at termination of the compression
step, and
Fig. 4 finally shows the plant after completed compression and in position for feeding
out the treated waste from the plant.
Description of the invention
[0006] Such as mentioned in the introduction the invention refers to a method and a device
for further treating such a mainly solid waste, which shall not be fed to the very
purification plant and which therefore before reaching this is caught and conveyed
up to the plant shown in the drawings.
[0007] As the invention does not concern the catching or conveying of the waste and as devices
for such purpose are earlier known, that part of the process will not be further described.
It shall only be mentioned that such devices generally comprise some member, which
may be lowered into the chute, and through which the waste water may pass, but not
the solid waste here concerned. This member is further combined with a conveyor, e.g.
a bucket chain, which conveys the collected waste to the device shown in the drawings,
which in the figures have been given the general designation 1.
[0008] At the embodiment shown the plant incorporates a compactor 1 formed as a cylinder
2, in which is displaceably arranged a feed piston 3, which as can be seen in fig.
1 is tubular, thus that it can house a pressure medium actuated cylinder 4, which
at 5 is articulatedly connected to the rearmost end of the compactor cylinder 2. The
piston bar of the cylinder 4 is at 6 articulatedly connected to the feed piston 3.
Through this extends one or more channels, which terminate with nozzles 7 opening
in the end surface of the feed piston 3. At the upper side of the compactor cylinder
2 is connected a feeding portion 8, which has a preferably hopper-formed opening 9,
through which the waste is introduced into the cylinder 2.
[0009] To the cylinder 2 is further connected a chamber 10 arranged perpendicularly thereto
in which is displaceably arranged a slide 11, which has a wall portion 11′ with a
shape and size adapted so to the cross section of the cylinder 2, that it covers the
through opening of the cylinder when the slide 11 is in the positon shown in fig.
1
[0010] A cylinder 12, which is actuated by pressure medium, is at 13 articulatedly connected
to an attachment in the chamber 10 and the piston bar 14 of the cylinder is articulatedly
connected to the slide 11. In the wall portion 11′ thereof is provided a number of
channels or grooves 15, which communicate with openings 16 situated outside the compactor
cylinder 2.
[0011] 17 designates a high pressure pump formed as a piston pump, incorporating a cylinder
18 with a tandem piston 19, which is displaceable, on one hand in the cylinder 18,
and on the other hand in a pressure medium actuated cylinder 20. Through a conduit
21 provided with a non-return valve 23 the cylinder 18 is connected to a water reservoar
22 and from the cylinder 18 extends a conduit 24 provided with a non-return valve
23, which is in direct connection with the channel or those channels in the feed piston
3, which lead to the nozzles 7.
[0012] By means of actuators known per se the now described pressure medium actuated units
are acutated in such a manner that the operation processes, which will now be described,
can be accomplished automatically.
[0013] In the position of the active members shown in fig. 1, these members can be defined
as situated in an inactive ready position. In this position the feed piston 3 is retracted
thus, that waste can fall down freely into the compactor cylinder 2 via the hopper-formed
opening 9. The cylinder 4, which is double acting, thereby has its piston bar in a
retracted position. The piston bar of the cylinder 12, which is likewise double acting,
is however in extended position, whereby the slide 11 separates the compactor cylinder
2 from a pipe socket formed as an extension of the cylinder.
[0014] The cylinder 19, which also is double acting has its piston bar withdrawn, whereby
also the piston 18 is in its retracted position in the cylinder 17. This is filled
with water, which has earlier been sucked up from the water reservoar 22. As the non-return
valves 23 are adapted to open for flow upwards in Fig. 1 but to block flow in opposite
direction, it is understood that the sucking up of water is effected at the movement
of the piston 18 to the right in the figure, whereas the water under pressure flows
through the conduit 24, when the piston 18 moves in opposite direction.
[0015] According to fig. 2 the feed piston has moved the waste introduced through the opening
9 in a direction against the slide 11, by activating the cylinder 4. In this connection
it should be mentioned that the cylinder 4 and its piston bar never will come in contact
with the waste or the waste water, which has accompanied this as the cylinder 4 acts
inside the feed piston 3, which last-mentioned therefore must stand all contact with
the waste and the water. As the slide 11 is situated in its lowermost blocking position,
it is evident that the waste, during this feed movement, has been compressed to some
extent. Simultaneously with this pressing movement the cylinder 20 is activated, whereby
the piston 19 under high pressure presses water via the conduit 24 and the channels
in the feed piston 3 to nozzles 7 under generation of strong water jets. The waste
will thereby be washed, which means, that the main part of the nasty-smelling matters
present in the waste, will be mixed with the water and be displaced with this. Such
as earlier mentioned the wall portion of the slide 11 has a number of channels, grooves
or the like 15, through which the water is distributed to the openings 16 from which
it is brought back to the chute, which leads the water to the purifying plant.
[0016] At the following compression of the waste the piston 3 of course can make a number
of reciprocating strokes in order to collect a bigger quantity of waste whereby is
effected, depending on the circumstances, such as the nature of the material and the
amount of compacting, a more or less dry and rather solid consistency of the press-cake
formed from the waste residuals.
[0017] In fig. 4 is shown a situation where the cylinder 12 is in its raised position thus
that the passage to the adjoining pipe socket is free. For terminating an operation
cycle cylinder 4 is then again actuated, thus that the feed piston 3 can continue
its movement to the left, thus that the compressed waste mass B is moved past the
chamber 10, where it bumps into a mass A which has been compacted during an earlier
operation cycle.
[0018] The waste mass which leaves the cylinder 2 has mainly lost its nasty-smelling tone
and can be in form of a stiff cake or be formed as briquettes, which can be supplied
to a destruction plant, e.g. an incineration station or be taken care of in another
manner.
[0019] It is evident that the steps now described in a operation cycle can be distinct or
more or less successively change over into each other. Compression and water injection
can be performed several times within the same cycle.
[0020] In practice the supply of waste takes place from the chute generally at non-regular
interwalls and with varying quantities. It can then be chosen to let the operation
cycle start first after the part of the cylinder 2 situated between the feed piston
3 and the wall portion 11 in fig. 1 is entirely or partly filled with waste or it
is possible to let the feed piston make several strokes for successively forwarding
the waste prior to the performing of the actual compression step. For this purpose
is of course used conventional sensing and actuating means.
[0021] Instead of the feed piston 3 which is displaceable in the cylinder 2 it is possible
to use a compacting screw, e.g. of the type which nowadays is used for injection moulding
of thermal plastic materials. Beside or instead of the nozzles 7 provided at a feed
piston for injection of water it is also possible to effect a water injection through
the part of the cylinder wall 2 which is situated between the feeding part 8 and the
slide 11. At least one of the channels 15 should extend outside the cylinder for discharge
of the liquid. It is also possible to open and close the channels 15 and/or the openings
16 alternatingly for obtaining a chock-formed liquid through flow. Such a chock-formed
effect can of course also be obtained by corresponding control of the cylinder 19
or by particular valve provisions. The wall portion 11′ can also consist of a rotatable
disc or the like provided in slots in the cylinder, and which in turn can have nozzles
7 connected to the high pressure pump 17.
[0022] It is evident that the operation process with conventional means can be made entirely
automatic.
1. A method for treating such comparatively solid waste, which for purification in
a purifying plant is conveyed in a chute or the like,
characterized therein,
that said waste is conveyed up form the chute or the like and into a compacting and
dewatering plant (1), where it is at one hand compressed while giving off liquid and
on the other hand is washed out in that water under high pressure is forced through
it, whereby the liquid and the washing water are preferably brought back to the chute
for purification, while the compacted waste is shaped into cakes, briquettes or the
like, and is fed out from the plant.
2. A method as claimed in claim 1,
characterized therein,
that the waste in a first step is compressed so much, that a part of its liquid content
is removed, that water under pressure in a second step is forced through the waste
and that it in third step is compressed while giving off the main part of its liquid
content, whereby the discharging liquids are brought back to the waste water.
3. A method as claimed in claims 1-2,
characterized therein,
that at least the compacting and dewatering steps entirely or partly coincide.
4. A device for performing the method as claimed in claim 1,
characterized therein,
that it has a cylinder (2), a feeding-in part (8), which is preferably hopper-formed
and connected to said cylinder, and through which waste can be introduced in the cylinder,
a displaceable wall portion (11), which from an active position, in which it mainly
covers the cylinder cross section, can be displaced to an inactive position, in which
it exposes said cross section, a compacting member (3) arranged in the cylinder and
which at actuation has the ability, with said wall portion (11) as a counterstay,
to compress waste introduced in the cylinder, one or more nozzles (7) or openings
for introduction in said cylinder of water unbder high pressure and one or more openings
(15,16) for discharge of liquid from the cylinder (2).
5. A device as claimed in claim 4,
characterized therein,
that the compacting member consists of a feed piston (3) displaceably aranged in the
compacting cylinder (2), which piston in is end surface has at least some of the nozzles
(7), through which waten is sprayed into the cylinder.
6. A device as claimed in claim 4,
characterized therein,
that the displaceable wall (11) forms part of a slide (11a), which is displaceable
perpendicularly to the cylinder.
7. A device as claimed in claim 4,
characterized therein,
that the displaceable wall (11) in its end surface facing the compacting member (3)
has e number of grooves or channels (15) of which at least one extends outside the
cylinder (2) for liquid discharge from the cylinder.
8. A device as claimed in claims 4-5,
characterized therein,
that the feed piston (3) has a length exceeding the axial length of the opening (9)
of the feeding-in part (8) so much, that the feed piston covers said opening during
its entire compacting and feeding-out stroke, and that the feed piston has an axial
recess starting from one of its ends and having such dimensions that the pressure
medium actuated cylinder-piston unit (4) can be housed therein for the displacement
of the feed piston.