WO2015019305A1

WO2015019305A1 - Plant and method of treatment of organic waste

Info

Publication number: WO2015019305A1
Application number: PCT/IB2014/063745
Authority: WO
Inventors: Loris Bressan
Original assignee: AMBIENTALIA Srl
Current assignee: AMBIENTALIA Srl
Priority date: 2013-08-07
Filing date: 2014-08-06
Publication date: 2015-02-12
Anticipated expiration: 2016-02-07
Also published as: ITBO20130453A1

Abstract

Described is a plant for treating organic waste for producing compost, comprising an area (2) for storing organic waste (4), means (22) for introducing and extracting air to and from the storage area (2), means (19) for filtering the air extracted from the storage area (2), a plurality of removable containers (3) for accumulating the organic waste (4), the containers (3) being manoeuvrable individually for being filled with organic waste (4) and inserted in succession inside the storage area (2).

Description

DESCRIPTION

PLANT AND METHOD OF TREATMENT OF ORGANIC WASTE Technical field

This invention relates to a plant for treating organic waste.

More specifically, this invention relates to a plant for treating organic waste for producing compost.

Moreover, this invention relates to a method for producing compost. Background art

The term "compost" generally indicates the result of the decomposition of a mixture of organic materials (such as pruning waste, kitchen waste, manure, garden waste such as leaves and cut grass) by macro and microorganisms under certain conditions, firstly the presence of oxygen.

Technically, the treatment of organic waste for producing compost, also called "composting", is an aerobic biological process producing a mixture of humified substances (the compost) starting from plant residue, both green and woody, or even animal waste using the action of bacteria and fungi.

The prior art composting plants, at an industrial level, are very large and in order to be economically competitive they must embrace a very large catchment of users.

There are prior art plants equipped with very large organic waste storage areas, with a total capacity in the order of tens or tonnes per year.

The movement of these masses of organic waste requires the use of mechanical means and numerous operators as well as a considerable size of the total area occupied by the plant.

The prior art organic waste treatment plants therefore have the drawback of not finding application in small communities, such as, for example, villages with a few thousand inhabitants. These villages must therefore organise a costly network for transferring the organic waste to the larger plants.

This circumstance, even though it is not particularly onerous for villages close to urban areas or not far from existing composting plants, appears, on the other hand, particularly penalising in the case of villages far from these plants and even more so for isolated villages such as those in mountainous area or on islands. In these cases, the transport of the organic waste becomes particularly onerous and sometimes even impossible, such as, for example, during the winter months, when snow or rough seas render these villages even more isolated.

Even tourist resorts find themselves in difficulty, during the high season, in dealing with costly seasonal transport services which, on the contrary, during the low season cannot be justified, thereby causing an over-sizing of the service and the means used for this purpose.

Disclosure of the invention

The aim of this invention is therefore to provide a plant for treating organic waste for producing compost which allows the drawbacks of the prior art plants to be overcome.

This aim is fully achieved by the waste treatment plant according to this invention as characterised in the appended claims.

A further aim of this invention is to provide a method for producing compost inside the above-mentioned plant.

Brief description of drawings

The technical characteristics of the invention, with reference to the above aims, are clearly described in the claims below and its advantages are more apparent from the detailed description which follows, with reference to the accompanying drawings which illustrate a preferred embodiment of the invention provided merely by way of example without limiting the scope of the inventive concept, and in which: Figure 1 is a schematic perspective view from above of a first embodiment of the waste treatment plant according to this invention;

Figure 2 is a schematic front elevation view of the plant of Figure 1 ;

Figure 3 is a schematic plan view from above of the plant of the previous figures;

Figure 4 is a section view through the line IV-IV of Figure 3;

Figure 5 is a perspective view from above of a detail of the plant of the previous figures;

Figure 5a is side cross section elevation view of the detail of Figure

5.

Figure 6 is a perspective view from above of the detail of Figure 5 in a different configuration;

Figure 7 is a perspective view from above of another embodiment of the detail of Figures 5 and 6;

Figure 8 is a schematic perspective view from above with some parts cut away to better illustrate others of a second embodiment of the waste treatment plant according to this invention;

Figure 9 is a schematic perspective view from above of a third embodiment of the waste treatment plant according to this invention;

Figure 10 is a schematic plan view from above of another embodiment of the detail of Figures 5 to 7;

Figures 11 and 12 illustrate respective perspective views from different angles of a further embodiment of the detail of Figures 5 to 7.

Detailed description of preferred embodiments of the invention

As shown in Figures 1 to 4, the reference numeral 1 denotes in its entirety a first embodiment of a plant for treating organic waste for producing compost according to this invention.

As illustrated in particular in Figures 1 and 2, the plant 1 for treatment of organic waste for producing compost comprises a plurality of area 2 for storing organic waste. Advantageously, each storage area 2 in the plant 1 is separated from the adjacent one.

As illustrated in Figure 3, each storage area 2 has a main longitudinal direction of extension D1.

Each storage area 2 is designed to house a plurality of removable containers 3 for accumulating the organic waste 4, the containers 3 being designed to be inserted in succession inside the storage area 2.

More specifically, as illustrated in the accompanying drawings, the removable containers 3 are positioned in succession inside the storage area 2 along the above-mentioned direction D1.

The containers 3 are advantageously limited in size, in such a way that they can be manoeuvred individually, once filled with organic waste 4, even with common, manually operated pallet transporters, which are not illustrated or, in the case of container 3 illustrated in Figure 11 , by suitable vehicles designed for pulling.

Advantageously, the container 3 has the shape of a parallelepiped and its substantially quadrangular base has sides not longer than 2 metres.

Again with reference to Figures 1 to 4, the plant 1 comprises a station 5 for pumping air to be introduced inside the organic waste 4 so as to facilitate the oxidisation process of the organic material.

A first pipe 6, which reaches each storage area 2, extends from the pumping station 5.

At each storage area 2, a manifold pipe 7 for introducing air inside the storage area 2 extends from the first pipe 6.

In turn, a plurality of first conduits 8 extend from the manifold pipe 7, designed to be connected to respective removable containers 3, when these are inserted, full of waste 4, inside the storage area 2.

Each first conduit 8 is connected to the respective container 3 at a relative lower area 3a, where a special opening 9 is made, as illustrated in Figures 5 and 6.

Preferably, the first conduit 8 is of the flexible type. Advantageously, each first conduit 8 has a respective on-off valve, not illustrated, to allow the passage of air only in the presence of a relative container 3.

As illustrated in Figure 5, which is shown full of organic waste 4, the container 3 is shaped substantially like a parallelepiped and has four feet 10 positioned at the corners of the relative base 11.

The feet 10 allow the container 3 to remain above the ground, so as to be easily moved with a common pallet transporter the forks of which can therefore be inserted in the space between the base 11 and the ground. At the above-mentioned lower area 3a, the container 3 comprises a bottom wall 12, supporting the waste accumulated therein.

The bottom wall 12 has a plurality of through holes 13.

The bottom wall 12 and the above-mentioned base 11 delimit, above and below, respectively, a hollow space 14 for collecting percolate forming during treatment of the organic waste.

The base 11 is advantageously made with a concave shape in such a way as to convey the above-mentioned percolate towards a single point, at which an opening 15 is made for draining the percolate towards the outside.

The above-mentioned opening 9 is connected to the hollow space 14. The air introduced inside the hollow space 14 through the opening 9, passing through the holes 13 made in the bottom wall 12 reaches the waste 4 accumulated in the container 3.

The opening 9, the hollow space 14 and the through holes 13 made in the bottom wall 12 form, in their entirety, means 16 for distributing the air inside each removable container 3.

As clearly illustrated in Figure 6, the removable container 3 comprises a swinging door 17 for unloading the compost.

With reference to Figures 1 to 4, the plant 1 comprises a suction station 18 for extracting from the storage areas 2 the substantially polluted and evil- smelling air generated during treatment of the organic waste 4. The air is then sent to filtering means 19 designed both to reduce polluting agents and remove further possible causes of the bas smell.

As shown in Figure 1 , a second pipe 20 connected to each storage area 2 extends from the above-mentioned suction station 18, for extracting air from the storage areas 2.

At the outlet of the second pipe 20, in each storage area 2, there is a choke valve 21 designed to adjust the flow rate of air sucked as a function of the various steps for treating the waste 4 during production of the compost.

Usefully, but not necessarily, the action for pumping the air and the action for extracting the air are performed using the same air processing machine.

The above-mentioned pumping station 5 and suction station 18, first and second pipe 6, 20, manifold pipe 7, first conduits 8, choke valves 21 form, in their entirety, for the plant 1 , means 22 for introducing and extracting air to and from the storage areas 2.

With reference to the first embodiment of the plant 1 illustrated in Figures 1 to 4, each storage area 2 comprises a cover 23, perimeter walls 24 which delimit the space, an access door 25 and a flooring 26.

The flooring 26 of the storage area 2 is watertight.

The flooring 26 of the storage area 2 is shaped for conveying the percolate discharged from the removable containers 3 to a collection pit 27.

As illustrated in Figure 4, the flooring 26 of each storage area 2 has a central tank 28 with a longitudinal extension inside of which the containers

3 are positioned in succession along the above-mentioned direction D1.

The tank 28 advantageously has two sloping sections converging towards the centre to form a channel 29 for drainage of the percolate, the channel

29 in turn having a slope, along the direction D1 , such as to convey the percolate towards the above-mentioned drainage pit 27.

The flooring 26 is advantageously made from concrete.

The collection pit 27 is advantageously located below ground level, so as to allow collection of the percolate by gravity, without requiring any pumping device.

The above-mentioned opening 15 made in the base 11 of the removable container 3, together with the concave base 11 , form, for the container 3, respective means 30 for draining the percolate.

Figure 8 shows an alternative embodiment, denoted by the reference numeral 1 ', of the treatment plant illustrated in Figures 1 to 4 and up to now indicated with the reference numeral 1.

The plant V differs from the plant 1 described above basically in that it comprises the extraction of the air directly from each container 3 rather than from the storage area 2 as a whole.

In this regard, as illustrated in Figure 8, wherein, for clarity, no cover of the storage area 2 has been shown, the storage area is not delimited by lateral walls and/or bottom walls and/or doors as each removable container is substantially isolated from the outside environment.

In effect, as can be also seen in Figures 7 and 1 1 , in which containers 3 especially dedicated to the plant V are shown (in different embodiments), the containers 3 have a cover 31 for conveying towards a second extraction conduit 32 the substantially polluted and evil-smelling air which is generated inside.

In detail, in Figures 8 and 9, the plant V is illustrated comprising removable containers 3 in the embodiment of Figure 7.

The second extraction conduit 32 is connected, by a respective manifold pipe 33, to the second pipe 20 extending from the storage area 2 for extracting air.

The construction of the plant 1 ' allows, by adopting the above-mentioned covers 31 and relative second conduits 32 and manifold pipe 33, the infrastructures such as lateral walls, bottom walls and doors, designed to render each storage area 2 substantially gas tight, to be eliminated.

Figure 9 shows an embodiment of the plant V of Figure 8, equipped with a plurality of storage areas 2 positioned side by side. For the above-mentioned reasons, the absence of lateral walls delimiting the storage areas 2 makes two adjacent storage areas 2 substantially communicating.

With regard to features not explicitly described of the plants 1' of Figures 8 and 9, reference is made to the above description of the plant 1 of Figures 1 to 4.

In use, as shown in Figures 1 to 6, the organic waste treatment plant 1 comprises the successive filling of the containers 3 and their insertion in the storage area 2.

In other words, an operator fills a container 3 of organic waste 4 at a predetermined rate as a function of the average production of the community which supplies its waste to the plant 1.

Before filling the container 3, the organic waste 4 undergoes mixing and, if necessary, integration with wooden material (chippings or the like) according to known technical methods in the sector.

The container 3 full of waste 4 is then inserted inside a storage area 2 in such a way as to fill the areas 2 in succession.

Advantageously, in view of the reduced dimensions of each container 3, the container, as mentioned, is easily moved even by a single operator by using a common pallet transporter.

Once the removable container 3 has been inserted inside the storage area 2, a first conduit 8, present inside the storage area 2, must be connected to the opening 9 present in the lower area 3a of the container 3, to allow the introduction of air inside using the methods described above.

In this way, the process of accelerated oxidisation of the organic waste 4, which is a crucial step in the composting process, is activated inside each container 3.

Once the operations for inserting the removable container 3 inside the relative storage area 2 have been completed the operator closes the access door 25 to the storage area.

When, with at least one container 3 positioned inside the storage area 2 and already in the treatment step, the operator must open the access door 25, for example to insert a new removable container 3, the means 22 for introducing and extracting air quickly change the air inside the storage area 2, in such a way as to avoid any risk of intoxication for the operator. Advantageously, this function activates automatically with the opening of the access door 25.

Advantageously, the means 22 for introducing and extracting air comprise, for each storage area 2, a special fan, not illustrated, designed for the air change operation.

Each removable container 3 must remain inside the storage area 2 for a predetermined time, usually in the order of thirty days, so that the composting process can be completed.

The period of time indicated clearly depends on many factors and it is therefore to considered purely as an example.

During the above-mentioned period, the percolate formed inside the mass of organic waste 4 falls into the hollow space 14 through the holes 13 made in the bottom wall 2 and, from the hollow space 14, reaches the flooring 26 through the drainage opening 15.

As described above, due to the slope of the drainage channel 29, the percolate is then conveyed towards the collection pit 27.

Similarly to what was described above for the plant 1 , also in the case of the plants 1' illustrated in Figures 8 and 9, there is the successive filling of the containers 3 (for example of the type illustrated in Figures 7 and 11) and their insertion in the storage area 2.

Also here, an operator fills a container 3' with organic waste 4, at a predetermined rate, before mixing and, if necessary, integration with wooden material (chippings or the like) according to known technical methods in the sector.

The container 3 full of waste 4 is then covered with a respective cover 31 and inserted inside the storage area 2 in such a way as to fill the area(s) 2 in succession. Once the removable container 3' has been inserted inside the storage area 2, a first conduit 8, present inside the storage area 2, is connected to the opening 9 present in the lower area 3a of the container 3', to allow the introduction of air inside using the methods described above. Simultaneously, the second extraction conduit 32 must be connected, by a manifold pipe 33, to the second pipe 20 for extracting air.

In both the plants 1 , 1 ' described above, the air extracted from the storage areas 2 or directly from the removable containers 3' is directed to the filtering means 19.

As already indicated above, the operation of the plant V is explained with reference to Figures 8 and 9 in which containers 3 are shown in accordance with the embodiment of Figure 7. Similarly, even though with limited modifications not illustrated in the detail, the operation of the plant 1 ' is to be considered extended to the containers 3 according to the embodiment illustrated in Figures 11 and 12.

Advantageously, a temperature detector, not illustrated in the accompanying drawings, is positioned inside each removable container 3. The plant 1 , 1' according to this invention comprises a control unit, not illustrated, for controlling all the steps for treating the organic waste 4 inside each removable container 3, by checking the temperature of the waste 4 placed inside each container 3, adjusting the introduction of air inside each container 3 and also adjusting the extraction of air produced in the composting process.

The control of the introduction and extraction of the air and the relative adjustment over time, together with the control of the temperature, allow, using the above-mentioned control unit, the timing and the quality of the result to be optimised.

As illustrated in Figure 10, in an alternative embodiment, the removable container 3 comprises a blade 34 for moving the organic waste 4 inside it during the composting treatment, in such a way as to amalgamate the waste and facilitate the distribution of the air. Experiments have shown that such a turning action reduces the time for treatment of the organic waste inside the plant according to this invention, as well as allowing the production of a compost with homogeneous characteristics.

As shown in Figure 10, the blade 34 is moved by a motor unit 35, advantageously of the hydraulic or electric type.

The blade 34 illustrated in Figure 10 is helical in shape and is pivoted on two opposite walls of the container 3.

According to alternative embodiments not illustrated, the blade 34 is made in a cantilever-style fashion.

As illustrated in Figure 11 , in an alternative embodiment, the removable container 3 comprises, in a similar manner to that described with reference to Figure 10, a blade 34 for moving the organic waste 4 inside it during the composting treatment, in such a way as to amalgamate the waste and facilitate the distribution of the air.

As shown in Figure 12, the blade 34 is moved (that is, rotated about its axis X) by a motor unit, preferably of the hydraulic type, which is not visible as it is concealed from view.

The blade 34 illustrated in Figure 11 is helical in shape and is pivoted on two opposite walls of the container 3.

In detail, the blade 34 has two portions 34a, 34b shaped in the form of a spiral with opposite windings, one to the right and the other to the left, in such a way as to create a movement of the mass of waste 4 guided towards the central part of the blade 34.

In other words, each spiral-shaped portion 34a, 34b defines a screw conveyor.

With reference to the different embodiments illustrated of the container 3, the blade 34 and the motor unit 35 form, in their entirety, for the container 3, respective means 36 for turning the organic waste 4 contained therein. As illustrated in Figures 11 and 12, an opening 37 for unloading the compost obtained from the waste 4 is made on a side wall 3L of the removable container 3.

The opening 37 can be opened and closed by means of a respective cover 38.

The cover 38 is slidable and actuated by a respective actuator cylinder 38a.

The opening 37 is made facing the above-mentioned central part of the blade 34, in such a way that the movement of the waste 4, not illustrated in Figures 11 and 12, generated by the blade 34, is such as to push the compost, with the opening 37 actually open, towards the outside of the container 3.

The removable container 3 also has a belt conveyor 39 connected below to the opening 37.

The conveyor 39 has a conveyor belt 40 looped around respective pulleys, non illustrated, of which one is motorised by means of a respective hydraulic motor 41.

The opening 37, the cover 38 and the conveyor belt 39 define as a whole, for the container 3, means 47 for unloading the compost towards the outside of the container 3.

As illustrated in Figure 12, the removable container 3 is equipped with, mounted on its front wall, a control unit 42 for the measurement, processing and transmission of operational parameters of the composting process inside the container 3.

The control unit 42 processes values acquired by means of sensors, illustrated, designed to measure inside the container 3 parameters such as, for example, temperature, oxygen concentration etc..

Again with reference to Figures 11 and 12, the container 3 is advantageously associated with a carriage 43.

The carriage 43 is positioned beneath the actual container 3 and supports the latter, facilitating the movement.

The carriage 43 has a metal frame 44, two wheels 45 advantageously fitted with tyres and coupling means 46 for pulling by a vehicle not illustrated.

Unlike the containers 3 illustrated in Figures 4 to 9, for the movement of which a special forklift truck equipped with forks or the like is necessary, the container 3 of Figures 11 and 12 can also be moved and manoeuvred by hand or with the use of a simple tractor.

Advantageously, the invention described above achieves the preset aims, providing a plant with simplified control and requiring minimum intervention, even by a single operator.

Claims

1. A plant for treating organic waste for the production of compost, comprising:

- an area (2) for storing organic waste (4),

- means (22) for introducing and extracting air to and from the storage area (2),

- means (19) for filtering the air extracted from the storage area (2),

- a plurality of removable containers (3) for accumulating the organic waste (4), the containers (3) being manoeuvrable individually for being filled with organic waste (4) and inserted in succession inside the storage area (2), characterised in that it comprises means for turning the organic waste (4) contained inside the removable container (3).

2. The plant according to claim 1 , characterised in that the means for turning the waste (4) comprise a blade (34) inserted in the container (3) and a motor unit (36) for moving the blade (34).

3. The plant according to claim 2, characterised in that the blade (35) has at least one spiral-shaped portion (34a, 34b).

4. The plant according to any one of claims 1 to 3, characterised in that it comprises means (47) of unloading the compost obtained from the waste (4) contained inside the removable container.

5. The plant according to claim 4, characterised in that the means (47) of unloading the compost comprise a conveyor unit (39) mounted on the removable container.

6. The plant according to claim 5, characterised in that the unloading means comprise an unloading opening (37), which can be closed, facing the conveyor unit (39), the at least one portion (34a, 34b) of the blade (34) shaped in the form of a spiral being designed to push the compost at the unloading opening (37) to actuate the unloading of the container (3) by means of the conveyor unit (39).

7. The plant according to any one of claims 1 to 6, characterised in that it comprises a carriage (43) associated with the removable container (3), the carriage (43) supporting the container (3) and having at least two wheels (45) for moving the container (3).

8. The plant according to claim 7, characterised in that the carriage (43) comprises coupling means (47) for pulling by a vehicle.

9. The plant according to any one of claims 1 to 8, characterised in that the means (22) for introducing and extracting air comprise, for each of the removable containers (3), a respective first conduit (8) designed to be connected to the container (3) for introducing air inside it when the container (3) is positioned in the area (2) for storing organic waste (4).

10. The plant according to claim 9, characterised in that means (22) for introducing and extracting air comprise a manifold pipe (7) for introducing air and a plurality of first conduits (8) designed to be connected to respective removable containers (3), the first conduits (8) originating from the manifold pipe (7).

11. The plant according to any one of claims 1 to 10, wherein each of the removable containers (3) has respective means (30) for draining percolate, characterised in that the storage area (2) has a watertight flooring (26), the flooring (26) being designed to convey the percolate discharged from the removable containers (3) to a respective collection pit (27).

12. The plant according to any one of claims 1 to 11 , characterised in that the storage area (2) has a main longitudinal direction of extension (D1) along which direction (D1) the removable containers (3; 3') are positioned in succession.

13. The plant according to any one of claims 1 to 12, characterised in that it comprises a cover (23), perimeter walls (24) for delimiting the storage area (2), and at least one access door (25) for introducing and extracting the removable containers (3) to and from the storage area (2).

14. The plant according to any one of claims 1 to 13, characterised in that it comprises a plurality of the storage area (2) positioned side by side.

15. The plant according to any one of claims 1 to 14, characterised in that each removable container (3) comprises means (16) for distributing air introduced inside.

16. The plant according to claim 8, wherein each removable container (3) comprises a bottom wall (12) supporting the organic waste (4) accumulated therein, characterised in that the air distribution means (16) comprise a plurality of holes (13) made in the bottom wall (12), for introducing air towards the waste (4).

17. The plant according to claim 16, characterised in that each container (3; 3') comprises a hollow space (14), delimited above by the bottom wall (12), the hollow space (14) being designed to collect the percolate coming from the organic waste (4) present in the container (3), and in that the hollow space (14) has a drainage opening (15) for conveying the percolate to the outside of the container (3).

18. The plant according to any one of claims 1 to 17, characterised in that the removable container (3) has a swinging door (17) for unloading the compost.

19. The plant according to any one of claims 1 to 18, characterised in that means (22) for introducing and extracting air comprise, for each of the removable containers (3'), a respective second conduit (32) designed to be connected to the container (3') to extract air from inside when the container (3') is positioned inside the area (2) for storing organic waste (4).

20. The method for producing compost inside a plant (1 , 1 ') for treating organic waste according to any one of claims 1 to 19, characterised in that it comprises the steps of:

- preparing an area (2) for storing organic waste,

- preparing a plurality of removable containers (3) for accumulating organic waste (4),

- filling in succession each container (3) and inserting it inside the area (2),

- introducing air inside the container (3) present in the area (2).

21. The method according to claim 20, characterised in that the step of introducing air inside the container (3) present in the area (2) comprises the step of connecting each container (3; 3') to means (22) for introducing air through a respective first conduit (8).

22. The method according to claim 16 or 17, characterised in that it comprises the steps of sucking the air close to the containers (3) and treating the air by special filtering means (19).