WO2016157086A1

WO2016157086A1 - Compact and transportable system for the production of pellets

Info

Publication number: WO2016157086A1
Application number: PCT/IB2016/051783
Authority: WO
Inventors: Alesssandro STRAGLIOTTO
Original assignee: Atena Solution Srl
Priority date: 2015-04-01
Filing date: 2016-03-30
Publication date: 2016-10-06

Abstract

The invention is a system (1) for the production of pellets, comprising a lower platform (2) on which the following are positioned and housed: a grinding station (3) for grinding the material to be treated, a first conveyor belt (4) provided with means for removing at least the metallic impurities from the ground material, a refining station (5), a cyclone (6) for separating the lightest fraction, a pellet machine (7), and wherein said platform (2) is of the unloadable type and in turn comprises one or more stabilizer and/or self-lifting feet (22).

Description

COMPACT AND TRANSPORTABLE SYSTEM FOR THE PRODUCTION OF PELLETS

DESCRIPTION

The present patent concerns the systems for producing pellets and in particular it concerns a new compact and transportable system for producing pellets.

Systems are known that are suited to produce pellets, meaning solid fuel obtained from material generally derived from wood, which is ground, dried, compressed and extruded in order to obtain small cylindrical bodies.

Said systems for the production of pellets require the use of several pieces of equipment used in sequence.

The raw material used for the production of pellets substantially consists of wood scraps, usually deriving from woodworking lines, which first of all are reduced in small-sized pieces by means of grinding devices.

Said ground material can also be dried in driers, generally hot air driers, and any parts that are not made of wood, for example metal parts, must be removed from said ground material.

The ground material must be further reduced to saw dust. Said operation is generally performed by refining devices, which grind the material even further.

The saw dust obtained in this way is conveyed into a pellet machine, in turn comprising rollers suited to transport the material and force it through at least one extruder in order to obtain an extruded cylinder that is successively cut by means of at least one knife unit, thus obtaining the pellets.

Said systems require wide spaces, both due to the overall dimensions of each one of the necessary pieces of equipment, and in order to leave a manoeuvring space around the machine for the operators, the conveyor belts that transport the material from a machine to another and/or for the movement of the means that transport the material from a machine to another.

Woodworking systems are known that produce a high quantity of wood waste. These systems need a suitable waste disposal apparatus for the disposal of said waste and therefore it is necessary to use a certain number of vehicles in continuous operation to remove the waste and transport it to another disposal location, or it is necessary to install pellet production systems that, as already explained, require wide spaces and money investments.

Woodworking systems are also known that produce a reduced and discontinuous quantity of wood waste, so that such limited quantity of waste does not justify the installation of systems for the production of pellets.

In this case, therefore, the material must be accumulated and its removal must be organized once a sufficient quantity has been reached.

In order to overcome the drawbacks illustrated above, a new type of compact and transportable system has been designed and produced that can be used for the disposal of waste preferably deriving from wood and for the production of pellets.

The object of the present invention is to provide a system that has a compact structure, so that it can be entirely housed on a frame of the transportable type, for example in or as a normal container.

It is another object of the present invention to provide a system that is always in perfect operating conditions after transport, with no need for any reinstallation or retesting.

It is another object of the present invention to provide a system that can be moved to different places of use, so that it can temporarily serve woodworking systems having a limited production of wood waste that can be used for the production of pellets.

It is another object of the present invention to provide a system that has reduced overall dimensions.

It is another object of the present invention to provide a system that can be installed anywhere, being furthermore provided with an independent generator.

These and other direct and complementary objects are achieved by the new compact and transportable system for the production of pellets, which among its main parts comprises the following:

• at least one grinding station for grinding the material to be treated; • at least one first conveyor belt provided with means for removing any impurities from the ground material, such as, for example, metal parts, said first belt being furthermore suited to transport the material leaving said grinding station to at least one refining station;

· said at least one refining station;

• at least one first centrifugal dust separator or cyclone, comprising at least one silo provided with means for the forced tangential introduction of air and of the material coming from said at least one refining station into the silo itself, and suited to separate the lightest fraction from the fraction that has to be conveyed to at least one pellet machine;

• said at least one pellet machine suited to receive said material coming from said cyclone and to produce pellets;

• means for transporting the pellets from said pellet machine to a cooling station;

• at least one pellet cooling station, possibly provided with one or more further screens for separating fine fractions and means for transporting the pellets;

• means for transporting the pellets from said cooling station to said sack-filling station;

• said at least one sack-filling station, where the pellets fall or are introduced, in general, into one or more sacks or containers;

· at least one lower platform on which at least said grinding station, said first conveyor belt, said refining station, said centrifugal dust separator, said pellet machine, said cooling station and said sack-filling station are positioned and housed,

and wherein said platform is of the unloadable type and in turn comprises one or more stabilizer and/or self-lifting feet.

Said system may also comprise a lateral containment structure suited to be installed on said platform, wherein said containment structure may comprise a frame and one or more side and/or top walls mounted on said frame. Said system preferably comprises also an independent generator, for example powered with fuel, suited to power said equipment.

Said system may also comprise at least one drying station, for example positioned downstream of said grinding station.

Said system may also comprise at least one filtering device suited to filter the air drawn by said cyclone for abating the dust that is generated in particular during the refining step. Said centrifugal dust separator, in greater detail, comprises a substantially cylindrical silo or container suited to be positioned with substantially vertical axis, at least one fan for the forced tangential introduction of air and of the refined material in said silo, at least one air outlet duct, if necessary connected to a suction system that may also filter the air, at least one material discharge opening, said discharge opening being made on the bottom of said silo, at least one auger or transport device suited to transport the material leaving the silo to said pellet machine.

In proximity to the top of said silo there is at least one baffle plate, in turn comprising a substantially truncated cone-shaped wall with vertex directed upwards, and one or more partitions mounted on the external surface of said truncated cone-shaped wall and arranged radially.

Said baffle plate has the function to separate the finer fraction of the material introduced from the heavier fraction that falls on the bottom of the silo due to gravity.

Once having been assembled the new system, made up as described above, is ready to be used and can also be installed in a normal container or transported as a normal container and, once having been unloaded in the designated place, it can be used immediately, with no need for installation and testing operations.

The overall dimensions of the system, once this has been installed in the designated place, are thus limited to the dimensions of the platform and the containment frame, in addition to the space necessary for performing the operations required to load the material to be treated.

Said new system can thus be rapidly transported and installed, so that it can be temporarily used in woodworking systems with a reduced production of waste, while it can be installed permanently in woodworking systems with a high production of waste occupying minimal space.

The characteristics of the new system will be highlighted in greater detail in the following description with reference to the attached drawings that are enclosed hereto by way of non- limiting example.

Figure 1 shows a schematic front view of the new system (1), while Figure 2 shows a schematic plan view of the new system (1).

Figure 3 shows a front view of the platform (2) with a frame structure (21) and stabilizer and/or self-lifting feet (22).

Figure 4 shows a plan view only of the platform (2) with the stabilizer feet (22).

Figure 5 shows a side view of the centrifugal dust separator (6), while Figure 6 shows a three-dimensional view of the centrifugal dust separator (6).

The invention is a compact and transportable system (1) for the production of pellets that is entirely positioned on a platform (2) of the unloadable type, for example having the size of a container or suited to be transported as a container.

Said platform (2) preferably comprises one or more stabilizer and/or self-lifting feet (22) and one or more systems for controlling the correct horizontal position of the platform (2). Said system (1) comprises, installed on said platform (2), at least one grinding station (3) suited to grind the material to be treated, comprising at least one feedbox (31) suited to load the material, preferably from above, at least one chamber (32) and at least one outlet or discharge duct (33) for the ground material.

Said system (1) also comprises at least one first conveyor belt (4) suited to transport the material flowing out of said discharge duct (33) of said grinding station (3) and at least one refining station (5).

Said first conveyor belt (4) preferably comprises means for removing any impurities from the ground material, for example metal parts.

Said at least one refining station (5) is suited to receive the ground material and in turn comprises at least one inlet opening (51) from which the material is introduced, preferably from above, cutting members and at least one outlet opening (52), preferably located in a lower position.

The refined material is drawn by means of at least one fan (53) suited to force said material and air into at least one centrifugal dust separator or cyclone (6) through at least one inlet duct (63).

Said cyclone is suited to separate the lightest, and dust-like fraction from the fraction to be conveyed to at least one pellet machine (7).

Said cyclone (6) comprises at least one substantially cylindrical silo or container (61) provided with a cylindrical wall (611), with a preferably inclined bottom (612) and an upper cover (613), said cyclone (6) being suited to be positioned with substantially vertical axis (6x).

Said cylindrical wall (611), in proximity to said cover (613), is provided with at least one opening (62) for the introduction of said refined material and air, and wherein said opening (62) is provided with said inlet duct (63) oriented tangentially to the cylindrical wall (611). Said cyclone (6) comprises also at least one duct (64) suited to suck the air contained in said silo (61) and connected to a dedicated suction system, said suction duct (64) being, for example, in a substantially axial position on said cover (613) of said silo (61).

Said bottom (612) of the silo (61) is provided with at least one discharge opening (65) that is suited to discharge the material and is connected to at least one auger (71) or another device for extracting the material and transporting it to said pellet machine (7).

Inside said silo (61), on the bottom (612), there is preferably at least one moving paddle device (66), for example with three paddles and of the rotary type, suited to move the material that accumulates on the bottom (612) and to transport it towards said discharge opening (65).

In proximity to the top of said silo (61) there is at least one baffle plate (67) that in turn comprises a substantially truncated cone-shaped wall (671) that is preferably coaxial with said silo (61), with vertex directed upwards. One or more partitions (672) substantially arranged radially are mounted on the outside of said truncated cone-shaped wall (671).

The material leaving said cyclone (6) is transported by means of the auger (71) to said at least one pellet machine (7), where said material is extruded and cut, thus obtaining the pellets.

The pellets leaving said pellet machine (7) are transported through at least one second conveyor belt (72) to at least one cooling station (8), for example comprising a silo (81), possibly provided with one or more further underlying screens (82) suited to separate the light and dust-like fractions or residues in general from the pellets.

Said silo (81) of the cooling station (8) is suited to contain the pellets leaving said pellet machine (7) for a time of permanence calculated according to the weight and/or the temperature of the material and sufficient to cool the pellets, which must reach a suitable temperature for the successive sack-filling or packaging process.

The pellets leaving said cooling station (8) are transported through at least one conveyor belt (91) to at least one sack- filling station (9), from which the pellets fall or are introduced, in general, in one or more sacks or containers (92).

In the preferred embodiment, said system (1) also comprises at least one filtering device (10) suited to filter the air sucked by said cyclone (6), in order to abate the dust that is generated especially during the refining step.

According to the invention, in order to optimize the available spaces and thus make the system more compact, said stations and pieces of equipment are arranged along a substantially U-shaped line, starting from a first end or short side (23) of said platform (2), in the order specified below:

1) said grinding station (3), in proximity to said first end (23) of said platform (2); the drying station, if any, is positioned near said grinding station (3) and aligned with respect to the long sides (24, 26) of said platform (2);

2) said first conveyor belt (4), arranged in a first advance direction (X) substantially parallel and close to a first long side (24) of said platform (2); 3) said refining station (5), aligned along said first advance direction (X) of said first conveyor belt (4);

4) said cyclone (6), close to said refining station (5) and aligned along said first advance direction (X) of said first conveyor belt (4);

5) said pellet machine (7), close to the opposite end or second short side (25) of said platform (2);

6) said cooling station (8) close to said pellet machine (7) and to the second long side (26) of said platform (2);

7) said sack-filling station (9) aligned with said cooling station (8) along a second advance direction (Y) of the material substantially parallel to said first advance direction (X), but in the opposite sense, and to said long sides (24, 26) of the platform (2).

The remaining space on said platform (2) can be usefully exploited, for example, for the installation of said air filtering device (10).

Said system may also comprise a lateral containment structure (21) suited to be installed on said platform (2).

Therefore, with reference to the above description and to the attached drawings, the following claims are expressed.

Claims

1. System (1) for the production of pellets, characterized in that it comprises:

• at least one grinding station (3) for grinding the material to be treated;

• at least one first conveyor belt (4) provided with means for removing at least the metallic impurities from the ground material, said first belt (4) being furthermore suited to transport the material leaving said grinding station (3) towards at least one refining station (5);

• said at least one refining station (5);

• at least one first centrifugal dust separator or cyclone (6), comprising at least one silo (61) provided with means (53, 63) for the forced tangential introduction of air and of the material coming from said at least one refining station (5) into the silo itself, and suited to separate the lightest fraction from the fraction that has to be conveyed to at least one pellet machine (7);

• said at least one pellet machine (7) suited to receive said material coming from said cyclone (6) and to produce pellets;

• at least one lower platform (2) on which at least said grinding station (3), said first conveyor belt (4), said refining station (5), said centrifugal dust separator (6), said pellet machine (7) are positioned and housed,

and wherein said platform (2) is of the unloadable type and in turn comprises one or more stabilizer and/or self-lifting feet (22).

2. System (1) according to claim 1, characterized in that it also comprises at least one independent generator installed on said at least one platform (2) and suited to power all the other pieces of equipment (3, 4, 5, 6, 7, 9, 10).

3. System (1) according to claims 1 or 2, characterized in that it also comprises, downstream of said pellet machine (7):

• transport means (72) suited to transport the pellets from said pellet machine (7) to at least one cooling station (8);

• said at least one pellet cooling station (8), possibly provided with one or more further screens (82) for screening fine fractions;

• transport means (91) suited to transport the pellets from said cooling station (8) to said sack filling station (9);

• said at least one sack filling station (9), where the pellets fall or are introduced, in general, into one or more sacks or containers (92).

4. System (1) according to the preceding claims, characterized in that it comprises also a lateral containment structure (21) suited to be installed on said platform (2), wherein said containment structure (21) comprises a frame and one or more side and/or upper walls.

5. System (1) according to the preceding claims, characterized in that it comprises also at least one drying station located downstream of said grinding station (3).

6. System (1) according to the preceding claims, characterized in that it comprises also at least one filtering device (10) suited to filter the air drawn by said cyclone (6) for dust abatement.

7. System (1) according to the preceding claims, characterized in that said platform (2) also comprises one or more control systems suited to control the correct horizontal position of the platform (2) itself.

8. System (1) according to the preceding claims, characterized in that it comprises at least one suction fan (53) suited to suck the refined material leaving said at least one refining station (5) and suited to forcedly introduce said material and air into said at least one centrifugal dust separator or cyclone (6) by means of at least one inlet duct (63).

9. System (1) according to the preceding claims, characterized in that said cyclone (6) comprises:

• at least one substantially cylindrical silo or container (61) provided with a cylindrical wall (611), a bottom (612) and an upper cover (613), said cyclone (6) being suited to be positioned with substantially vertical axis (6x); • at least one opening (62) for the introduction of said refined material and air, created in said cylindrical wall (611), and wherein said inlet duct (63) is installed on said opening (62), oriented tangentially with respect to the cylindrical wall (611) itself;

· at least one duct (64) suited to draw the air contained in said silo (61) and connected to a suction system;

• at least one discharge opening (65) suited to discharge the material and created on said bottom (612) of the silo (61), to which at least one auger (71) or other device for extracting said material and coveying it to said pellet machine (7) is connected;

• at least one baffle plate (67) mounted inside said silo (61) in proximity to its top, said baffle plate (67) in turn comprising a substantially truncated cone-shaped wall (671) with its vertex directed upwards and one or more substantially radial partitions (672) mounted on the outside of said truncated cone-shaped wall (671).

10. System (1) according to the preceding claims, characterized in that said stations (3, 5, 8, 9) and pieces of equipment (4, 6, 7) are arranged on said platform (2) along a substantially U-shaped line in the following order, starting from one end (23) or first short side of said platform (2):

• said grinding station (3), in proximity to said end or first short side (23) of said platform (2);

• said first conveyor belt (4), arranged in a first advance direction (X) substantially parallel and close to a first long side (24) of said platform (2);

• said refining station (5), aligned along said first advance direction (X) of said first conveyor belt (4);

· said cyclone (6), close to said refining station (5) and aligned along said first advance direction (X) of said first conveyor belt (4);

• said pellet machine (7), close to the opposite end or second short side (25) of said platform (2); said cooling station (8), close to said pellet machine (6) and to the second long side (26) of said platform (2);

said sack filling station (9), aligned with said cooling station (8) along a second advance direction (Y) of the material that is substantially parallel to said first advance direction (X), but in the opposite sense, and to said long sides (25, 26) of the platform (2).