Embodiments of the present invention relate to equipment for producing granules from plants coming, in particular, in the form of slash, trunks, or branches.
French patent FR-A-2491491 describes equipment for transforming ligneous wastes into combustible granules which comprises: a boiler fed with grinded barks from a silo of grinded barks; a dryer fed with combustion gas of the boiler and/or cooling air of the boiler exchanger, and with humid sawdust, from a humid sawdust silo; a cyclone separator of sawdust and smoke; a dry sawdust silo linked through a dosing box, a grinder, an a mixer to a granule press, the output of which opens onto a cooling and screening machine pouring the granules into an elevator; and silos for storing the granules.
A drawback of such equipment is the significant dimensions thereof.
A mobile system for producing granules from branches and leaves has been described in Japanese patent JP-A-2006231712, which comprises a grinder, a dryer, and a device for producing granules. To the inventor's knowledge, this system does not make it possible however to process highly humid plants, or to process plants comprising flammable compounds such as “spirits of turpentine.”
It is desirable to provide equipment for transforming plants into granules, the compactness of which is improved.
It is further desirable to provide equipment for producing granules from plants which is improved and/or solves, at least partially, the deficiencies or drawbacks of known devices for producing vegetal granules.
According to one aspect of the invention, equipment is provided for processing a ligneous material and includes a unit for the production of agglomerated particles of the ligneous material as well as a unit for the production of hot air from the ligneous material. The hot air is used for drying the particles of the ligneous material. The two production units are mounted on one (or more) mobile elongated load-bearing structure(s).
According to another aspect of the invention, equipment is provided for processing plants and includes a dryer arranged to provide dry sawdust and a compactor arranged to provide dry sawdust granules, in which the input of the compactor is directly linked, i.e. without an intermediate silo, to the output of the dryer to receive therefrom the dry sawdust, and in which the dryer and the compactor are mounted on at least one mobile chassis arranged to rest—or resting—on the ground. The equipment for processing plants further includes a hot air generator having a source of heat, such as a furnace, and a structure for carrying air, such as a beam of tubes, which is arranged to be heated by the source of heat while isolating from this source the air it carries, so as to avoid bringing particles or flammable compounds with the air carried by this structure.
In other words and according to another aspect of the invention, equipment is provided for the production of granules from plants that includes a dryer able to provide dry sawdust and a compactor able to provide dry sawdust granules, in which the dryer is arranged to substantially continuously provide the dry sawdust to the compactor, and in which the dryer and the compactor are mounted on at least one chassis able to rest—or resting—on the ground by means of feet or wheels.
In particular and according to another aspect of the invention, equipment is provided for the production of granules from slash, trunks, or branches. The equipment includes a first dryer able to dry chips, a grinder able to grind dried chips to provide sawdust, a second dryer able to dry sawdust and provide dry sawdust, and a compactor able to compact the dried sawdust and provide granules of dry sawdust, in which the first dryer performs a substantially continuous transfer of dried chips to the grinder, in which the grinder performs a substantially continuous transfer of grinded chips (sawdust) to the second dryer, in which the second dryer performs a substantially continuous transfer of dry sawdust to the compactor, and in which the first and second dryers, the grinder, and the compactor are mounted on at least one chassis able to rest—or resting—on the ground by means of retractable stabilizers or wheels.
According to another aspect of the invention, equipment according to claim 1 is provided.
Certain preferred embodiments of the invention are described below.
The equipment may further include a shredder able to shred slash, trunks, or branches, and to produce chips. The shredder is preferably mounted on the chassis.
The equipment may further include a granule cooler which is fed by the compactor and allows cooled granules to be provided to a packing or evacuation station. The cooler is preferably mounted on the chassis.
The dryer(s), and in that event the cooler, may include an elongated hollow cylinder body rotatively mounted (in relation to the chassis) according to its longitudinal axis which is substantially horizontal, i.e. slightly leaning in relation to a horizontal plane. The hollow body delineates a transfer tubular enclosure able to contain the chips—or sawdust—to be dried (respectively the granules to be cooled). The internal face of the wall of the hollow body delineating the tubular enclosure is preferably provided with projecting portions spreading along a line in helix which axis is substantially the same as the longitudinal axis of the hollow body. These projecting portions make it possible to cause, by the rotation of the hollow body according to its axis, the transfer along this axis of the particles—chips, sawdust, or granules—contained in the tubular enclosure. Thus, the dryer(s), and in that event the cooler, form one of the conveyors for transferring the products (particles) they contain.
The first and second dryers, and in that event the cooler, may substantially spread parallel to the longitudinal axis of the chassis, one above the other—or one near the other.
The equipment may further include a hot air generator connected to the dryer(s) to make hot air circulate therein and dry the chips—respectively the sawdust. The hot air generator is preferably mounted on the chassis. The hot air generator may include a hollow cylinder body elongated according to a substantially horizontal longitudinal axis. The hot air generator may spread substantially parallel to the longitudinal axis of the chassis, below the dryer(s)—or near it (them). The hot air generator may include a beam of tubes parallel to its longitudinal axis, a first end of each tube communicating with ambient air, and a second end of each tube communicating with the (second) dryer to make the air heated in the generator circulate therein.
The hot air generator may include a hearth having a shape elongated along its longitudinal axis. The hearth may receive a conveyor for carrying a solid combustible. The solid combustible may consist of wood chips provided by the shredder (or a second shredder).
The unit for the production of hot air may include a duct for carrying air from the cooler to the generator, which is equipped with a fan, a duct for carrying hot air from the generator to the second dryer, and a duct for carrying hot air from the second dryer to the first dryer.
The unit for the production of hot air may include a second shredder.
The shredder(s), the grinder, and the compactor may be arranged on a chassis common to the dryers, the cooler, and the generator, on each side of them.
The hot air production unit may include a separator for retaining cinders and separate them from smoke and combustion gas.
The equipment may include a unit for the production of electrical energy from a combustible, this unit being arranged on the load-bearing structure(s).
The load-bearing structure may include a false chassis which can be removed from a rolling support such as a road trailer, by way of fast unlock fasteners and stabilizing cylinders allowing the false chassis to be lifted and moved away from the rolling support.
The equipment may include a control unit (UC) linked to a weight sensor for continuously weighing shredded wood particles, to a sensor sensitive to the humidity of wood particles, and to a sensor sensitive to the temperature of the dryer(s). The control unit is arranged, in particular programmed, to modify an operating parameter of the unit (LPGcont) for the production of granules, such as the rate of advance of a conveyor (C1, S1, S2, REF) for carrying wood particles, and/or an operating parameter of the unit (GAC) for the production of hot air such as hot air speed or temperature, as a function of signals—or data—provided by the weight sensor, the humidity sensor, and the temperature sensor;
The equipment may include a fire detection and sprinkling control unit, this unit being arranged on the load-bearing structure(s).
Embodiments of the invention make it possible to easily and efficiently process various types of plants, in particular plants for which humidity is around 60 to 75%.
Other aspects, features, and advantages of the invention will be described in the following description in relation with, but not limited to the appended figures which show preferred embodiments of the invention.
The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
In the drawings:
The equipment according to the invention preferably integrates all the elements/components allowing granules to be produced, from the reception of slash, trunks and branches, to the granules packed in bags, big-bags, or in bulk.
Embodiments of the invention allow the equipment for producing granules to be mobile, the compactness and small size of the equipment allowing its components to be integrated on a mobile chassis and/or a road trailer.
Embodiments of the invention make it possible to reduce transport costs while allowing the equipment according to the embodiments of the invention to be installed near a plant collection area, for example in a clearing.
The equipment according to embodiments of the invention may, for example, have a productive capacity of 1 ton of granules per hour.
In the diagram shown in
One—and only one—unidirectional double arrow in continuous line represents the water going out of a condenser COND.
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With reference to
Each shredder D1, D2 respectively feeds an intermediate storage container T1, T2.
These intermediate storage containers T1, T2 allow the continuous production of granules to be stabilized, in cooperation with two motorized and regulated conveyors C1, C2, located at the output of these containers, and controlled by the control unit UC.
The shredded wood used for the production of granules must be clean from “impurities” (dust, sand, stones, and the like), to guarantee its quality and avoid damaging the equipment mechanism.
To that end, the wood can be filtered, for example by vibrating and screening, and/or can be separated from impurities by flotation and agitation in a settling basin (reference 4,
The operations of grinding the chips and agglomerating/granulating sawdust are helped by drying the wood particles which is performed between each step, avoiding “filling” cutting/compacting tools.
Drying the wood particles is performed in two drying tunnels S1, S2 equipped with “worms” and performing four simultaneous actions: conveying, agitating, drying, and containment of wood particles.
Before being conditioned, the granules produced must be cooled; the equipment comprises to that end a cooling tunnel REF (
The air intended to be heated by the furnace GAC (
The components of the mobile equipment according to an embodiment of the invention, in particular the dryers, the cooler and the generator GAC are arranged on a common chassis 38, 39 so as to create, for hot air and wood particles, a “zigzag” travel according to a “back and forth” pattern. This arrangement allows the inputs and outputs of the elements performing the successive operations of the process method to be brought nearer.
The heated air circulates from one tunnel to another thanks to transfer chambers/ducts which channel the air with little loss. This configuration allows one hot air current to be used.
Although the hot air required for drying can be produced by a conventional generator operating on gas, fuel oil, or electrical energy, hot air is advantageously produced by a furnace (GAC) in which slash of low value is burnt.
The hot air generator includes an air carrying structure having a beam of tubes, which is heated by the source of heat and which isolates the air it carries from this source, so as to avoid carrying flammable particles or compounds.
This furnace has an elongated shape and dimensions which are near those of the three conveyor tunnels S1, S2, REF, which helps the integration side by side of these compounds onto a common mobile chassis.
So as to avoid cinders produced by the furnace GAC from being susceptible of causing fires, the smoke exhaust duct of the generator GAC may be equipped with a separator LAV for example performing cyclonic sucking and centrifugal water film.
The residual humidity of the wood particles varies, from a drying tunnel to the other, in particular according to the conveying speed of wood particles in the tunnels.
For example, for an air temperature of around 350° C. and an air circulating speed in the tunnels of around 0.5 m/s, the transit time of wood particles in each tunnel may be around one hour.
The conveying speed of particles in the tunnels may be set by the unit UC controlling the tunnels driving motors, to guarantee a residual humidity of the granules in a range comprised between around 10% to around 15%, and thus help granule cohesion.
According to one embodiment, the conveying speed of the chips in the first dryer S1 is adjusted to guarantee a relative humidity of dried chips of around 20%, which then allows dried chips to be finely grinded without causing filling, and the conveying speed of sawdust in the second dryer S2 is adjusted to guarantee a relative humidity of dried sawdust of around 8 to 12%, which facilitates the subsequent compaction thereof.
The equipment according to an embodiment of the invention is preferably equipped with an electrical generator powering the elements (grinders, compactor, tunnels) of the equipment.
The electrical energy is produced by a generator using the heat generated by the furnace, for example in the form of water vapor.
The chassis of the equipment is equipped with platforms facilitating maintenance and troubleshooting operations at “shoulder height”. These platforms equipped with guardrails may be retractable to limit the width of the equipment to the road clearance.
The granule conditioning elements are adapted to the format of the desired packing, or to the transfer by blowing to a storage container in bulk installed on a truck or a second trailer.
The load-bearing structure 38, 39 of the equipment comprises a retractable platform of the tailgate type, placed at one end of the chassis, to facilitate handling and packing operations.
The equipment according to the invention may comprise a fire suppression system mainly consisting of a stock of water, a pump and a sprinkling circuit. The pump may be driven by a thermal motor and connected on the one hand to a semi-rigid hose-reel, on the other hand to sprinklers.
The stock of water may be used to feed the settling basin, the smoke washer, and the fire suppression system.
All the elements of the equipment according to an embodiment of the invention may be fixed onto a false chassis 39 (
The false chassis may be equipped with stabilizing feet 40 (
The false chassis can be removed from its rolling support, thanks to fast unlock fasteners and stabilizing cylinders allowing it to be lifted and moved away from its rolling support, a trailer for example. The fact that the equipment can be removed from its support allows the mobile support to be used for other purposes.
On the contrary, for small duration operations, the equipment according to the invention may be operated on its mobile support. In that case, the tires may be protected from heat by thermal shields.
With reference to
A discharge ramp of the shredder D1 opens onto an intermediate storage container T1, the volume of which may be around 1 m3, i.e. around 30 minutes of consumption of the line LPGcont.
Disintegrated wood is partially extracted from this sink by a conveyor 3 (
The conveyor 3 feeds a sedimentation tank 4 equipped with an agitator (not shown) which precipitates the dense particles (stone, sand, metals, and the like) to separate them from the chips.
The sedimentation tank has a worm (not shown) scraping the bottom to evacuate dense particles.
An open work conveyor C1 used as drainer transfers the chips to the first drying tunnel S1.
The dryer/conveyor tunnel S1, which is substantially identical to the tunnels S2 and REF, includes a conveying worm conveying and agitating the wood particles.
To that end, the dryers S1, S2, and the cooler REF each include an elongated hollow cylinder body rotatively mounted according to their respective horizontal longitudinal axes 50, 51, 52. Each hollow body delineates a tubular transfer enclosure able to contain the chips—or the sawdust—to be dried, respectively the granules to be cooled.
The internal face of the wall of the hollow body is provided with projecting portions 53 (
The dryers and cooler spread substantially parallel to the longitudinal axis 54 of the chassis, one above the other—or one near the other.
The length of the cylinder hollow body (or drum) of the dryers and its adjustable rotation speed allow the transit time and therefore the drying duration to be set.
The first tunnel S1 opens onto a refining grinder BR (
The output of this grinder is equipped with a cyclone with exhaust duct introducing the sawdust into the second tunnel S2.
The tunnel S2 agitates and dries sawdust at an adjustable temperature from 200 to 700° C., and conveys it up to the granulator/compactor COM.
The compactor COM is equipped with compression rollers and can agglomerate sawdust into granules from 8 to 10 mm of diameter and 15 to 20 mm of length, for example.
A discharge ramp of the compactor introduces the granules into the cooling tunnel REF.
The tunnel REF agitates the granules and cools them by evacuating the calories by contact with the air sucked by the fan V1. The air sucked circulating against the granules cools them efficiently and separates dust from the granules—and brings dust with it.
The tunnel REF opens onto a dispenser allowing the conditioning to be selected by means of a rotating deflector (not shown) manually operated for example, which makes it possible to direct the granules, into a bag-filling machine 12, or in a “Big-Bag.”
The bag-filling machine 12 (
The handling platform 13 is part of the conditioning station EMB allowing an operator to perform/control several additional operations: shaping and closing the bags, filling in a first bag controlled by a weighing machine so as to calibrate filling-in, the weighing machine being integrated to a support frame of the station EMB; preparing and supporting a second bag receiving the granules after filling in the first bag.
A handling arm equipped with a handling element with a suction cup may be provided to help the operator stacking the bags onto a pallet.
A rotating plate 15 (
With reference to
This unit comprises the second shredder D2 of a capacity lower than that of the shredder D1, which reduces slash into disintegrated chips.
A discharge ramp of this shredder opens onto the intermediate storage container T2 allowing the heat energy produced by the furnace to be stabilized.
Disintegrated wood is extracted, in the lower part of this container T2 by a conveyor C2, to feed the furnace.
The rate of advance of the conveyor C2 is adjusted by the unit UC to maintain the temperature of the drying air going out of the furnace at a value for example near 350° C., in particular at a value slightly lower than 350° C. when the plants to be dried contain easily flammable compounds.
With reference to
The hot air generator includes a hollow cylinder body elongated according to a horizontal longitudinal axis 55 (
The hot air generator includes a beam 23 of tubes parallel to its longitudinal axis, a first end of each tube communicating with ambient air, and a second end of each tube communicating with the second dryer to make the air heated in the generator penetrate therein.
The hot air generator includes a hearth which shape is elongated along its longitudinal axis, the hearth receiving a carrying conveyor Ctrans which spreads parallel to this axis, which passes through the generator GAC and receives the shredded wood provided by the conveyor C2.
The conveyors C2 and Ctrans allow the intermediate storage T2 of the furnace to be isolated to avoid transmitting the fire.
The conveyor Ctrans moves “back and forth” respectively to distribute the combustible on the whole length of the hearth, by its upper face, and scrap ashes CEN to evacuate them, by its lower face.
The conveyors C2 and Ctrans are driven by the control unit UC with the same rate of advance.
The furnace GAC has in its lower part, on its whole length, a combustion chamber. This chamber has holes spaced out at equal distance from one another to stir up the fire, through the conveyor which moves the combustible.
An activation fan V2 pulsates fresh air into the combustion chamber at a speed optimizing the combustion of slash and reducing the volume of ashes.
The drying air fan V1 feeds the “organ” or beam 23 of longitudinal tubes offering a great surface of thermal exchange, which is placed in the higher part of the furnace.
The smokes produced by the furnace are channeled into a stack which evacuates them in the upper part of the equipment.
The cinders carried away with the smoke are eliminated and precipitated by a separator (washer) LAV. The washer and the fan V2 may be connected to a common drive shaft.
Extracting the smoke is performed in a chamber located above the organ, on the whole length of the furnace.
The fan V1 located at the output of the tunnel REF, sucks the air preheated in the tunnel, producing a depression helping to cool the granules.
A transfer chamber 26 includes the fan V1 injecting air into the furnace organ.
A transfer chamber 27 channels the hot air coming out from the organ of the furnace GAC to the tunnel S2.
A transfer chamber 28 channels the hot air coming out from the tunnel S2 to the tunnel S1. In its lower part, the chamber is provided with a hatch for evacuating sawdust to feed the compactor COM.
A chamber 29 evacuates the hot and humid air from the tunnel S1 toward outside, through a condenser COND. In its lower part, the chamber is provided with a hatch for evacuating shredded wood to feed the refining grinder BR.
With reference to
A control panel (not shown) linked to the control and command electronic unit UC displays: an overview diagram of the equipment identifying the location of the electrical elements and their controls; the safety indicators (temperature, water level, fuel level, faults); the electronic measurement results (weight of the materials processed at the input and the output in particular).
The production regulating automatism UC controls the rates of advance of the conveyors and tunnels so as to maintain the productive capacity per hour at the desired value.
For the granule production line LPGcont, the rate of advance may be slaved at the continuous weighing of shredded wood, measured on the conveyor C1 at the output of the sedimentation tank.
For the line of hot air production, the rate of advance may be slaved at the drying air temperature, in particular during transient phases of starting and stopping the equipment.
Regulating the drying air temperature allows a regular temperature to be maintained in the drying tunnels S1 and S2.
In parallel, the humidity rate required for good granule cohesion is measured in sawdust before compacting, by measuring the electrical conductivity of sawdust between metal electrodes in contact with the sawdust contained in the tunnel S2.
Maintaining this humidity rate in a range of desired values may for example be obtained by driving a power-operated valve for setting the evacuation of water vapor contained in the tunnel S2, and/or by automatically varying the temperature setpoint in the tunnel(s), and therefore the temperature of the drying air produced by the furnace.
With reference to
The pump 34 may supply a water discharge rate of around 250 l/mn under a pressure around 6 bars to simultaneously feed one or more ramps of sprinklers, if need be with the injection of an additive.
A water tank 35 of a volume around 3 m3 may be divided to avoid unbalance during the equipment travel.
Ramps equipped with sprinkling nozzles 36 may be fed by manual valves or electrically-operated valves controlled by thermal sensors.
With reference to
This false chassis is provided with hydraulic cylinders 40 allowing it to rest stable on the ground. The stabilizers 40 may be coupled one to the others by a central part to make the load uniform and correct the attitude of the equipment.
The false chassis is encircled by retractable platforms 41 for maintenance operations. The platforms have guardrails and access stairs. The set folds up vertically to match the road clearance.
A tailgate 42 constitutes a conditioning platform provided with guardrails and a retractable access stairway.
The tailgate comprises a turning plate 15 receiving a loading pallet for granule bags. The rotation of the plate allows a plastic film to be easily put on the pallet.
The structure comprises lateral canopies 43 which can be horizontally spread by cylinders to shelter operators and equipment from bad weather.
They may be used as intake areas when, as shown in
The canopies may include a circuit for the condensation of water vapor produced by drying wood particles. For example, the canopy walls may include a sandwich of 2 metal plates, one of which has a series of slanted folds, helping vapor condensation—in addition to strengthening the canopy, water flowing and collecting at the end of the canopy front and back. Feeding the canopies with water vapor may be made by the middle of the canopies, thus defining 4 condensation areas.
The water vapor condensated in the canopies, in particular when the canopies are also in the position shown in
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.
Number | Date | Country | Kind |
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08 03747 | Jul 2008 | FR | national |
This application is a Section 371 of International Application No. PCT/FR2009/000820, filed Jul. 2, 2009, which was published in the French language on Jan. 7, 2010, under International Publication No. WO 2010/000982 A2 and the disclosure of which is incorporated herein by reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/FR2009/000820 | 7/2/2009 | WO | 00 | 4/1/2011 |