Facility for the disinfestation of harvested cereals and method for the disinfestation of harvested cereals

Abstract

The invention relates to a disinfestation facility (1) for eradicating pest insects present in cereals, which comprises an enclosure (4) that receives cereals, a device (2) for creating a vacuum in the enclosure (4) containing cereals, a stirring device setting the cereals in motion inside the enclosure (4), a device (5) for injecting into the enclosure (4) a gaseous fluid that is harmful to the pest insects, the harmful gaseous fluid being injected after the vacuum has been applied, a device (15) for extracting and neutralising the gaseous fluid present in the enclosure (4), and a device for separating the eradicated pest insects from the cereals after treatment by means of the gaseous fluid. The invention also relates to a method for the disinfestation of the cereals, which comprises steps for eradicating the pest insects present in the cereals using an enclosure (4), the vacuum in this enclosure (4) and a gaseous fluid that is harmful to these pest insects.

Description

[0001] Description

[0002] Title

[0003] Plant for the disinfestation of harvested cereals and process for the disinfestation of harvested cereals

[0004] technical field

[0005] The present invention relates to the field of cereal treatment for the eradication of insect pests, for example Lepidoptera and Coleoptera, which remain present and develop in cereal crops stored in silos. The invention relates particularly to an installation for the disinfestation of harvested cereals and to a method for disinfestation of harvested cereals.

[0006] State of the art

[0007] Treating cereals is essential to limit the development of insect pests that infest harvested grains during silo storage and cause significant yield losses. Examples of affected cereals include, but are not limited to, wheat, oats, rye, barley, millet, maize, canary seed, rice, sorghum, teff, and buckwheat. Examples of insect pests include, but are not limited to, lepidopteran larvae and beetles, such as scarabs, ladybugs, stag beetles, leaf beetles, cockchafers, weevils, ground beetles, wood beetles, and flour beetles. Insecticides have been used for many years to control stored grains, but residues of these insecticides remain on the grains and are found in processed products. Regulations require that a threshold of insecticide residues in grains not be exceeded.Eventually, these insecticides will be banned for health and environmental reasons.

[0008] Preventive and curative solutions are being implemented to protect against insect pests during grain storage. To reduce the risk of infestation, a first step is to sanitize the premises, equipment, and harvesting machinery to ensure optimal working conditions (cleanliness, airtightness, air conditioning, heating, etc.). It is also possible to apply mineral powders to harvesting equipment and machinery, such as diatomaceous earth, and / or to disinfect silos and harvested grain by fumigation with hydrogen phosphide (PH3). Another measure involves preserving the stored grain from quality degradation, for example, by cooling the ambient air in the grain storage silo to inhibit insect development within the stored grain.Another measure involves continuously monitoring the risk of infestation, for example, by monitoring the appearance of insects at shallow depths in grain stocks using traps and / or automatic acoustic probes. Another measure is to treat the grain at harvest time, just before the storage period, prior to shipment, by fumigating the grain with hydrogen phosphide or phosphine (PH3) or by applying a mineral powder to the surface of the stored grain pile, such as diatomaceous earth.

[0009] The Applicant notes that the measures currently deployed are insufficient to eradicate the insect pests present in the grain stocks, still resulting in considerable yield losses.

[0010] The Applicant is aware of prior art JP409047211A, US20050112209A1, and US2021161179A1, which relate to facilities and / or methods for treating cereals to eradicate insect pests present in them. The Applicant notes, however, that these facilities and methods for treating cereals are not entirely effective and safe, and that they still result in considerable yield losses in stored grain.

[0011] Summary of the invention

[0012] The present invention aims to partially overcome this drawback and, to this end, proposes an insect control system for eradicating insect pests present in cereals after harvest. According to the invention, the insect control system comprises an enclosure configured to hold cereals. The capacity of the enclosure can vary considerably, for example, from a few hundred kilograms to several tons, or even several tens of tons, of cereals, which can influence the duration of the treatment in order to eradicate the maximum number of insect pests present in the cereals.

[0013] According to the invention, the pest control system also includes a vacuum device configured to create a vacuum within the enclosure when the grain is placed inside. Preferably, the vacuum device will be configured to provide a vacuum of less than four Torrs, and more preferably less than three Torrs. Creating a vacuum within the enclosure advantageously removes the air from the bodies of the insect pests present in the grain. According to the invention, the pest control system also includes an agitator configured to move the grain within the enclosure. This movement of the grain within the enclosure facilitates the removal of insect pests hidden within the grain and also promotes the detachment of insect pests that cling to the grain while still alive, as well as during or after eradication.According to the invention, the term agitation covers both agitation of the cereals, mixing of the cereals or vibration of the cereals, or even any other movement of the cereals in the enclosure, this movement making it possible to promote the exit of the insect pests of the grains where they are positioned, in particular when said insect pests are in lethargy and remain in the cereal grains, feeding on these cereal grains and possibly laying eggs there, which is in particular the case when the cereals are stored at low temperature.

[0014] According to the invention, the pest control system also includes an injection device configured to inject a gaseous fluid harmful to insect pests into the enclosure, said injection of the harmful gaseous fluid occurring after a vacuum has been created. The term "harmful gaseous fluid" covers any gaseous fluid capable of harming the health of insect pests during their treatment by the pest control system. The harmful gaseous fluid will preferably be ozone, but it could be carbon dioxide, hot air, or any other gaseous fluid harmful to insect pests and, preferably, capable of being easily neutralized after the eradication of the insect pests. Injecting the harmful gaseous fluid after a vacuum has been created advantageously allows the insect pests to be attacked from within the system by means of the harmful gaseous fluid.Unlike mammals, insects do not have a centralized respiratory system, but rather several respiratory systems composed of vacuoles, tracheae, and tracheoles. Vacuoles are located along their abdomen and consist of openings lined with myofibrils, forming valve-like structures. These vacuoles can remain closed for anywhere from a few minutes to several hours, depending on the insect pest. Tracheae are internal tubes that distribute air to the organs and appendages of the insect's body. The outermost branches of these tracheae are the tracheoles, which are on the order of micrometers in diameter and transport oxygen to the cells and muscles. Creating a vacuum in the enclosure induces anoxia, forcing the insects out of the grain in search of oxygen. Furthermore, this vacuum forces the vacuoles of the insect pests to remain open.Initially, the insect pests will enter a state of torpor and then die. Beetle-type insect pests have an exoskeleton made primarily of chitin, which is virtually rustproof. Due to the vacuum, the harmful gaseous fluid will penetrate the insect pests and irritate, then destroy, their tracheoles, causing their death either immediately after treatment or later, at most within 24 to 36 hours. Thanks to the prior action of agitating the grain, which helps to expel the insect pests from the cereal grains, and the vacuum created within the chamber, which also helps to expel the insect pests from the cereal grains while keeping their respiratory systems open, the harmful gaseous fluid can then act effectively on the insect pests to eradicate them almost completely.Whereas chemical treatments, such as those carried out according to the prior art, kill insect pests in cereal grains which, consequently, remain included in the cereals and cannot be separated from them after treatment.

[0015] According to the invention, the pest control system includes an extraction device configured to extract and neutralize the harmful gaseous fluid present in the enclosure. This prevents any release of the harmful gaseous fluid into the environment once it has been extracted from the enclosure. When the harmful gaseous fluid is hot air, the neutralization of the extracted hot air can occur naturally by release into the atmosphere or by means of a condenser to cool the air before its release into the atmosphere, for example. This air cooled by the condenser could also be reintroduced into the enclosure to cool the treated grain present there before its removal.

[0016] According to the invention, the pest control system includes a separation device configured to separate eradicated insect pests from the grain after treatment with the harmful gaseous fluid. This allows the grain to be cleaned of the eradicated insect pests, and the grain can then be returned to the silo or used for consumption or processing, for example into flour, while the eradicated insect pests can be destroyed, for example by incineration.

[0017] According to the invention, the term "includes an enclosure" means that the pest control system may consist of a single enclosure or several enclosures, each equipped with an agitation device, a vacuum device, an injection device, an extraction device, and a separation device, such as those mentioned above. The agitation device, vacuum device, injection device, extraction device, and / or separation device may be common to all or part of these enclosures. In other words, the pest control system may duplicate the enclosure one or more times, with the possibility of sharing or duplicating the agitation device, vacuum device, injection device, and / or extraction device one or more times.

[0018] According to one embodiment of the disinfestation installation of the invention, the enclosure comprises a drum mounted to rotate about a horizontal axis and configured to receive and contain grain. Furthermore, the installation includes a drive device for rotating the drum about the horizontal axis to agitate the grain within the drum. This allows the grain to be agitated within the drum by rotating said drum about the horizontal axis. "Horizontal" is understood to mean a strictly horizontal position of the axis, but also slight inclinations of this axis relative to the horizontal, for example, to facilitate the descent of the grain towards a lateral side of the drum during its removal after treatment. Additionally, according to a possible embodiment, the inner perimeter wall of the drum will include blades extending inwards towards the drum, these blades facilitating the mixing of the grain during the drum's rotation.A version of the drum without these blades is possible. Other versions of the installation remain possible for agitating the grain, for example, a container that is subjected to vibrations or in which arms are arranged to move and stir the grain within the container.

[0019] Preferably, according to this drum-based insect control system, the drum has a perimeter wall with perforations designed to allow the passage of air and the harmful gaseous fluid. This advantageously allows for the creation of a vacuum and the injection of the harmful gaseous fluid into a chamber containing the drum. The perforations allow the air inside the drum to escape, and once the drum is evacuated, the harmful gaseous fluid enters the drum to come into contact with the grain containing the insect pests. Alternatively, a solid drum, i.e., without perforations, could be used. In this case, the vacuum would be created directly within the drum by suction nozzles arranged on the drum, and the harmful gaseous fluid would be injected directly into the drum, for example, by means of harmful gaseous fluid injection nozzles arranged on the drum.Preferably, according to the aforementioned embodiment with a perforated drum, the perforations are configured to retain the grain within the enclosure and to allow the passage of insect pests after their eradication by means of the harmful gaseous fluid. Thus, once the insect pests present in the grain are eradicated, the drum can be rotated around the horizontal axis, which allows the eradicated insect pests to be brought against the inner contour wall of the drum. These insect pests, being smaller than the perforations, then pass through the drum, while the grain, whose kernels are larger than the perforations, remains inside the drum.The installation could separate the grain from the eradicated insect pests in a different way, for example, by emptying the grain that still contains the eradicated insect pests from the drum or other container and placing it on a screen to separate it from the eradicated insect pests. This separation of the treated grain from the eradicated insect pests could be carried out on-site or remotely from the facility, for example, at a different location than where the treatment is being performed to eradicate the insect pests present in the grain.

[0020] Preferably, according to this embodiment, the disinfestation installation includes a drum, said drum comprising an access hatch configured for inserting the grain to be treated into said drum and an extraction hatch configured for removing the grain after treatment and separation of the eradicated insect pests. A variant is conceivable with a drum comprising a single hatch allowing both the insertion of the grain into the drum and the extraction of the treated grain from the drum.

[0021] Preferably, according to an embodiment of the pest control installation in which the enclosure includes a drum, said enclosure includes a chamber configured to contain the drum, the chamber being configured to be sealed. Furthermore, the vacuum device includes a vacuum pump connected to the chamber to evacuate the air from said chamber. Preferably, according to this embodiment, the chamber includes an inlet door configured to open or close the chamber in a sealed manner, said inlet door allowing the grain to be treated to be inserted into the enclosure, and an outlet door configured to open or close the chamber in a sealed manner, said outlet door allowing the grain to be removed from the enclosure after treatment. However, an alternative remains possible with a single sealed door allowing the grain to be inserted into the enclosure and removed from the enclosure once said door is opened.Preferably, according to this embodiment, the chamber includes another exit door configured to open or close the chamber hermetically, said other exit door allowing the extraction of the eradicated insect pests from the enclosure, after the separation of the treated cereals and the eradicated insect pests.

[0022] According to one embodiment of the pest control plant of the invention, said pest control plant includes a grain conveying and removal device configured to insert grain to be treated into the chamber and to remove the treated grain, separated from the eradicated insects, from the chamber. This will facilitate the handling of the grain for treatment. When the pest control plant duplicates the chamber one or more times, the grain conveying and removal device may be common to all chambers or also duplicated one or more times.

[0023] According to one embodiment of the pest control installation of the invention, said pest control installation includes a device for removing eradicated insect pests after their separation from the grain. Preferably, this removal device is a screw conveyor onto which the eradicated insect pests fall after their separation from the grain, once the treatment with the harmful gaseous fluid has been carried out. The rotation of the screw conveyor moves the eradicated insect pests to an exit of the enclosure. However, a conveyor belt could be provided to transport the eradicated insect pests to an exit of the enclosure, or even other means of moving the eradicated insect pests to an exit of the enclosure.

[0024] According to one embodiment of the pest control installation of the invention, the injection device comprises an ozone production system, the harmful gaseous fluid being ozone. Furthermore, according to the invention, the extraction device comprises a suction system configured to draw the ozone contained in the enclosure and a catalyst configured to neutralize the ozone drawn from the enclosure. In an alternative embodiment, when the harmful gaseous fluid is hot air, the injection device comprises a hot air production system, for example, a hot air generator, configured to heat air to a temperature preferably reaching at least 80°C. In this case, the extraction device comprises a suction system configured to draw the hot air and, preferably, a condenser for cooling the air before releasing it into the atmosphere.By varying the settings, the air cooled by the condenser can be reinjected into the enclosure to cool the mass of grain being processed within it.

[0025] According to one embodiment of the pest control installation of the invention, the vacuum device comprises a vacuum pump. Preferably, the vacuum device also includes a steam ejector and a boiler, which will allow for faster vacuuming of a large-volume enclosure.

[0026] The invention also relates to a method for disinfesting cereals, which includes the following steps: conveying cereals into an enclosure; creating a vacuum in the enclosure; injecting a harmful gaseous fluid into the enclosure; agitating the cereals in the enclosure; extracting the harmful gaseous fluid from the enclosure after treatment of the cereals and eradication of the insect pests and neutralizing said harmful gaseous fluid extracted from the enclosure; separating the treated cereals from the eradicated insect pests.

[0027] Some of the aforementioned steps may be implemented successively or simultaneously, possibly in reverse order or repeated several times. For example, it would be possible to agitate the grain in the chamber, create a vacuum in the chamber, inject the harmful gaseous fluid into the chamber, then agitate the grain again, and finally extract the harmful gaseous fluid from the chamber. As another example, it would be possible to agitate the grain in the chamber and, simultaneously, create a vacuum in the chamber, inject the harmful gaseous fluid, and then continue agitating the grain in the chamber for a certain period before extracting the harmful gaseous fluid. Conversely, the harmful gaseous fluid could be extracted from the chamber while the grain is being agitated for a certain period.

[0028] Of course, it is possible to delay some of the steps or to keep some of the steps active for a certain period of time, especially after injection of the harmful gaseous fluid into the enclosure, in order to allow it to act on the pest insects.

[0029] Preferably, the process includes an additional step of removing the eradicated insect pests after their separation from the treated cereals.

[0030] Preferably, the process includes an additional step of extracting the treated cereals from the enclosure after their separation from the eradicated insect pests.

[0031] Brief description of the figures

[0032] The features and advantages of the invention will become apparent from the following description, which is supported by figures, including:

[0033] [Fig. 1]: Figure 1 schematically illustrates a non-limiting embodiment of a cereal disinsection installation according to the present invention;

[0034] [Fig. 2] and [Fig. 3]: Figures 2 and 3 schematically illustrate, from different viewpoints, an embodiment of an enclosure on a cereal disinsection installation according to the present invention;

[0035] [Fig. 4], [Fig. 5] and [Fig. 6]: Figures 4 to 6 schematically illustrate, from different viewpoints, another embodiment of an enclosure on a cereal disinsection installation according to the present invention; [Fig. 7]: Figure 7 schematically illustrates another non-limiting embodiment of a cereal disinsection installation according to the present invention;

[0036] [Fig. 8]: Figure 8 schematically illustrates another non-limiting embodiment of a cereal disinsection installation according to the present invention, the harmful gaseous fluid being hot air;

[0037] [Fig. 9] and [Fig. 10]: Figures 9 and 10 schematically illustrate another embodiment of a cereal disinsection installation according to the present invention, which comprises several chambers, each capable of treating cereals infected with insect pests.

[0038] Detailed description

[0039] In the following description: the term installation refers to the cereal disinsection installation that is the subject of the invention, unless otherwise indicated in the text; the same references are used to describe the same characteristics on the different embodiments of the cereal disinsection installation and the enclosure of this installation, unless otherwise indicated in the text; terms such as "high", "low", "lower", "upper", ... which may be used, will be used in consideration of the normal operating position of the disinsection installation resting on a horizontal support surface, for example a slab or a base.

[0040] Figure 1 schematically depicts an installation 1 comprising a vacuum device 2, a reactor 3 defining a chamber 4, and an injection device 5 for injecting a gaseous fluid harmful, particularly to insect pests present in cereals, preferably ozone. For this purpose, the injection device 5 includes an ozone production system 6 comprising an oxygen concentrator 7 and an ozonator 8, a first ozone reservoir 9, a compressor 10, and a second reservoir 11 containing compressed ozone, preferably at two bar. The injection device 5 also includes a first suction system 12 and a first catalyst 13 which allow the first reservoir 9 and the second reservoir 11 to be purged and the ozone to be converted back into oxygen before being released into the atmosphere.The vacuum device 2 includes a vacuum pump 14 which is connected to the enclosure 4 of the reactor 3 and will allow the air to be evacuated from this enclosure 4. The injection device 5 is also connected to the enclosure 4 of the reactor 3 and will allow ozone to be injected into this enclosure 4, once the vacuum has been achieved in this enclosure 4.

[0041] In Figure 1, installation 1 also includes an extraction device 15 connected to containment 4 of reactor 3. This device extracts ozone from containment 4, which has been injected into it for treatment of the grain. The grain has been previously placed in containment 4 and then evacuated. The extraction device 15 includes a second suction system 16 and a second catalyst 17, which extract the ozone from containment 4 and neutralize it, converting it back into oxygen before release into the atmosphere.

[0042] As shown schematically in Figure 1, a hydraulic circuit 18 and a plurality of valves 19i to 19io manage the circulation of air and ozone in the system 1 for creating a vacuum in chamber 4, filling chamber 4 with ozone, extracting the ozone from chamber 4 and the two reservoirs 9 and 11, and refilling chamber 4 with air after treatment. A programmable logic controller (PLC) (not shown) will manage the opening and closing of these valves 19i to 19io and also the activation of the other actuators in the system 1, for example, the motors mentioned below.

[0043] Figures 2 and 3 schematically illustrate a possible embodiment of reactor 3 in which containment 4 includes a chamber 20 with a door 20a providing access to the interior of containment 4, the door 20a being fitted with a sealing gasket 20b to close said chamber

[0044] 20 is sealed. The vacuum device 2 is connected to this chamber 20 in order to create a vacuum within it. For this purpose, the chamber 20 will be designed to withstand a vacuum exerting on the wall of the chamber 20 a pressure that is preferably less than four Torrs, and preferably less than three Torrs.

[0045] The enclosure 4 also includes a drum 21 which is mounted for rotation inside the chamber 20, about a first axis XI, which is preferably horizontal, although a slight inclination of this first axis XI with respect to the horizontal is possible. The reactor 3 includes a motor 22 which drives the drum 21 in rotation about the first axis XI via a drive shaft 23 which is mounted in a pivot joint about the first axis XI on the chamber 20, by means of a sealed bearing 24. Rollers 25 arranged in the chamber 20 also receive the contour wall 26 of the drum 21, the actuation of the motor 22 thus enabling the drum to be driven in rotation

[0046] 21 around the first axis XL. The drum 21 includes an access hatch 27 through which a conduit 28 passes. This conduit allows the grain to be injected into the drum 21 or, conversely, the grain to be extracted after ozone treatment. Preferably, the conduit for injecting the grain and the conduit for extracting the treated grain will be separate to avoid any risk of contamination of the treated grain by insect pests that may remain in the conduit used for injecting the grain. The access hatch 27 can be placed either in an open position for inserting the conduit 28 into the drum 21 or in a closed position to contain the grain within the drum 21.

[0047] The drum 21 is perforated and, for this purpose and preferably, includes perforations 29 arranged on the contour wall 26, as partially illustrated in Figure 2. These perforations 29 allow air to be evacuated from the drum 21 when air is evacuated from the chamber 20. These perforations 29 are sized to prevent the grain placed in the drum 21 from passing through the contour wall 26 of said drum 21 and, on the contrary, to allow the passage of pest insects which will be eradicated, as will be explained later.

[0048] During grain processing, the door 20a of chamber 20 is first opened, and the access hatch 27 of drum 21 is also opened to fill drum 21 with grain to be processed. Then, the access hatch 27 and door 20a are closed, sealing chamber 20. The vacuum pump 14 is then activated to create a vacuum in chamber 4, and the motor 22 is activated to agitate the grain in drum 21. This agitation of drum 21 can be achieved by rotating motor 22 in a single direction or by successively reversing the direction of rotation of motor 22. To facilitate this agitation of the grain in drum 21, the contour wall 26 may have blades 30 on its inner face 26a, as illustrated in Figure 3. This vacuum in drum 21 and this agitation of drum 21 will allow the grains and insects to be removed from the grain. pests that remained there in a state of lethargy.Preferably, the agitation of drum 21 should begin before the evacuation of chamber 20 to encourage the expulsion of cereal pests before the vacuum is created in chamber 20, but these steps could be carried out simultaneously. The vacuum in chamber 20 of enclosure 4 creates anoxic conditions in the enclosure, which also helps to expel pests embedded in the cereal grains in search of oxygen and, furthermore, keeps the vacuoles of the pests' respiratory system open. Injecting ozone into chamber 20 repressurizes enclosure 4 and forces the pests to breathe the ozone, which then penetrates their entire bodies, thus eradicating them from within in less than thirty-six hours.The agitation of drum 21, which continues after the chamber 20 is evacuated, detaches the eradicated insect pests from the cereal grains and allows these pests to pass through the perforations 29 on the contour wall 26 of drum 21, thus separating them from the treated grain. Activation of the second suction system 16 removes the ozone from chamber 4 and neutralizes it by passing it through the second catalyst 17, at which point chamber 20 of chamber 4 is filled with air. The door 20a of chamber 20, and the access hatch 27 of drum 21, can then be opened to remove the treated grain. Eradicated pest insects can also be removed from chamber 20, for example by means of a suction device which will store the eradicated pest insects in a container, before their destruction, for example in an incinerator.

[0049] A variant of reactor 3 is illustrated opposite Figures 4 to 6; this variant can be implemented on installation 1 shown in Figure 1 or on the variants of installation 1 shown in Figures 7 to 10 and described below. This reactor 3 comprises, as previously shown in Figures 2 and 3, a containment 4 which includes a chamber 20 in which is arranged a drum 21 with perforations 29. The drum 21 is mounted to rotate about a first axis XI, which is preferably horizontal, by means of rollers 25 arranged in the chamber 20. A motor 22 drives the rotation of said drum 21 via a drive shaft 23 which is mounted in a pivot joint along the first axis XI on the chamber 20, by means of a sealed bearing 24.

[0050] In Figure 4, chamber 20 includes, in its upper part, an entrance door 31 providing access to the interior of enclosure 4, the entrance door 31 being, for example, a sliding door, and a first sealing gasket 32 ​​allowing the entrance door 31 to be closed airtight. Chamber 20 includes, in its lower part, a first exit door 33 providing access to the interior of enclosure 4, the first exit door 33 being, for example, a sliding door, and a second sealing gasket 34 allowing the first exit door 33 to be closed airtight.Chamber 20 also includes, in its lower part and below the first exit door 33, a second exit door 35 providing access to the interior of the enclosure 4. This second exit door 35 may, for example, be a sliding door, and a third seal 34 allows the second exit door 35 to be closed airtight. These sliding doors could be replaced by hinged pivot doors. In Figure 4, the drum 21 includes a first access hatch 37 and a second access hatch 38, which are preferably sliding hatches. The chamber 20 and the drum 21 are configured so that the entrance door 31 and the first access hatch 37 can correspond in such a way as to introduce a first conduit 39 through the entrance door 31 and to house the end 39a of this first conduit 39 in the drum 21, by introducing it through the first access hatch 37.This first conduit 39 allows the drum 21 to be filled with grain to be processed. The chamber 20 and the drum 21 are also configured so that the first outlet door 33 and the second access hatch 38 can align to allow a second conduit 40 to be introduced through the first outlet door 33 and its end 40a to be inserted into the drum 21 through the second access hatch 38. This second conduit 40 allows the processed grain to be extracted from the drum 21.

[0051] In this figure 4, the reactor 3 also includes a device for removing eradicated pest insects 41, located under the drum 21, which may for example consist of a worm screw 42 driven in rotation about a second axis X2, preferably parallel to the first axis XI, by means of a second motor 43 and a second transmission shaft 44, this second transmission shaft 44 also being mounted on the chamber 20 by means of a sealed bearing 45 in order to be able to seal the chamber 20. The removal device 41 could be a conveyor belt, according to another embodiment not illustrated.A third conduit 46 is inserted into the chamber 20, through the second outlet door 35, so as to place the end 46a of this third conduit 46 in correspondence with the end 42a of the auger 42, in order to collect the eradicated pest insects that fall onto the auger 42 when the drum 21 is rotated and once the ozone treatment has been carried out, said eradicated pest insects passing through said drum 21, through the perforations 29. As illustrated in figures 5 and 6, the chamber 20 has a funnel shape 51 arranged between the drum 21 and the discharge device 41, in order to concentrate the eradicated pest insects that fall from the drum 21, above the auger 42.

[0052] The vacuum device 2 is connected to this chamber 20 in order to create a vacuum within it. For this purpose, the chamber 20 will be designed to withstand a vacuum exerting on the wall of the chamber 20 a pressure that is preferably less than four Torrs, preferably three Torrs.

[0053] During grain processing, the inlet door 31 of chamber 20 is first opened, and the first access hatch 37 of drum 21 is also opened to insert the first conduit 39 and fill drum 21 with grain to be processed. Then, the first access hatch 37 and the inlet door 31 are closed, thus sealing chamber 20. The vacuum pump 14 is then activated to generate a vacuum in enclosure 4, and the motor 22 is activated to agitate the grain in drum 21. Preferably, the agitation of drum 21 begins before the chamber 20 is evacuated and continues with it, then resumes after the vacuum in chamber 20 is released. To facilitate this agitation of the grain in drum 21, the contour wall 26 may have blades 30 on its inner face 26a, as illustrated in Figure 6.This agitation of the drum 21 will force the dormant insect pests from the cereal grains. The vacuum in chamber 4, and therefore in drum 21, also keeps the vacuoles of the insect pests' respiratory system open. Injecting ozone into chamber 20 repressurizes drum 21 and forces the insect pests to breathe the ozone, which penetrates their entire bodies, thus eradicating them from within in less than thirty-six hours. Activating the second suction system 16 removes the ozone from chamber 4 and neutralizes it by passing it through the second catalyst 17, at which point chamber 4 is filled with air. The second outlet 35 of chamber 20 can then be opened to introduce the third conduit 46.The rotation of the drum 21, by means of the motor 22, then makes it possible to detach the eradicated insect pests from the cereal grains and to pass these eradicated insect pests through the perforations 29 on the contour wall 26 of the drum 21, the eradicated insect pests being thus separated from the treated cereals and falling onto the evacuation device 41 which is simultaneously activated to evacuate these eradicated insect pests into the third conduit 46. Once the separation of the treated cereals and the eradicated insect pests has been carried out, the drum 21 stops rotating and the first exit door 33 of the chamber 20 can be opened as well as the second access hatch 38 on said drum 21, in order to introduce the second conduit 40 and to extract the treated cereals from the drum 21.

[0054] The first conduit 39 can be a conduit as such, forming an expulsion outlet, or a gutter, depending on the method of conveying the grain to chamber 4. For example, the grain may be conveyed naturally by gravity, via a conveyor belt, via a blower system, or by any other means of conveying suitable for transporting grain. Similarly, the second conduit 40 can be a conduit as such, forming an extraction outlet, or a gutter, depending on the method of extracting the grain from chamber 4. For example, extraction may be carried out using a suction system or naturally by gravity. The arrangement, shape, and dimensions of the first access hatch 37 and the second access hatch 38 can also be adapted to the drum 21, according to the chosen method of conveying the grain to be treated and the method of extracting the treated grain.Similarly, the third conduit 46 could be a conduit in itself, for example an extraction vent, or a gutter, depending on the method of removing the eradicated insect pests chosen, for example a suction system or a conveyor belt. The eradicated insect pests will then be transported to a destruction device, for example an incinerator.

[0055] In Figure 7, the variant of installation 1 differs slightly from that illustrated in Figure 1 and described previously. In this Figure 7, the vacuum device 2 includes, in addition to the vacuum pump 14, a steam ejector 47 and a boiler 48, which allow for faster vacuuming of the chamber 4, thus providing a larger capacity for processing grain. As with Figure 1, in Figure 7, installation 1 includes an injection device 5 for injecting a harmful gaseous fluid into the chamber 4. The injection device 5 includes an ozone production system 6, which comprises an oxygen concentrator 6 and an ozonator 7, and an ozone concentration chamber 49, which includes a homogenizing aspirator 50.The injection device 5 also includes a first suction system 12 and a first catalyst 13 which allow the concentration chamber 49 to be purged and the ozone to be neutralized in order to transform it back into di oxygen, before release into the atmosphere. Installation 1 also includes an extraction device 15 for extracting ozone from enclosure 4, after ozone treatment of cereals, and for neutralizing this ozone extracted from enclosure 4, said extraction device 15 comprising a second suction system 16 and a second catalyst 17. As schematically shown in this figure 7, a hydraulic circuit 18 and a plurality of valves 19i to 199 allow the circulation of air and ozone on installation 1 to be managed for creating a vacuum in enclosure 4, filling enclosure 4 with ozone, extracting ozone from enclosure 4 and from the ozone concentration chamber 49 and for filling enclosure 4 with air after treatment.A programmable logic controller (not shown) will manage the openings of these valves 19i to 199 and also the other actuators of the installation 1.

[0056] Alternative embodiments of the installation 1 and the enclosure 4 may be considered. For example, the injection device 5 may be designed to produce and inject into the enclosure a harmful gaseous fluid, other than ozone, for example carbon dioxide, hydrogen phosphide (PH3) or hot air, the extraction device 15 then being adapted accordingly in order to neutralize said harmful gaseous fluid after its extraction from the enclosure 4.The enclosure 4 could comprise a container designed to be opened to allow the direct introduction of grain to be treated, then hermetically sealed to create a vacuum directly within it. A vibrating or stirring system agitates the grain within the container. The vacuum device 2, the injection device 5, and the extraction device 15 are directly connected to this container. The container is emptied of the treated grain, which still contains the eradicated insect pests. The separation of the treated grain and the eradicated insect pests is carried out on a separation device configured for this purpose, located at a distance from the container or at a different site than where the container is located. Other embodiments of the enclosure 4 or of the installation 1 remain conceivable within the scope of the invention as defined by the following claims.

[0057] Alternatively, installation 1 could, for example, incorporate the characteristics described previously with reference to Figure 1 or Figure 4, with an adaptation of the injection device 5 and the extraction device 15, the harmful gaseous fluid being hot air, preferably hot air capable of reaching a temperature of at least 80°C, depending on the treatment process selected. In this case, as schematically illustrated in Figure 8, the injection device 5 will include a hot air production system 52, for example a hot air generator, configured to heat air to a temperature of up to 80°C, and a first hot air extraction system 53 and a first condenser 54 configured to remove and lower the temperature of excess hot air produced by the hot air production system 52.The extraction device 15 will, for example, include a second hot air intake system 55 and a second condenser 56 configured to remove hot air from enclosure 4 and lower its temperature before release into the atmosphere. Alternatively, instead of releasing the air cooled by the second condenser 56 into the atmosphere, this cooled air could be reinjected into enclosure 4 of reactor 3 to mix the grain after its hot air treatment, thereby cooling the treated grain mass before its removal from enclosure 4.As shown schematically in Figure 8, a hydraulic circuit 18 and a plurality of valves 19i to 19? manage the circulation of ambient air and hot air in the installation 1 for creating a vacuum in chamber 4, filling chamber 4 with hot air, extracting hot air from chamber 4 and the hot air production system 52, and filling chamber 4 with ambient air, or even cold air, after treatment. A programmable logic controller (PLC) (not shown) will manage the opening and closing of these valves 19i to 19? and also the activation of other actuators in installation 1, such as motors.

[0058] Regarding the cycle of treating cereals with hot air, this can for example be carried out in the following way: partial or maximum vacuuming to remove insect pests from the contaminated cereals, with mixing of the mass of cereals previously placed in chamber 4; returning chamber 4 to atmospheric pressure with hot air at a preferred temperature of 80°C; maintaining the entire mass of cereals in chamber 4 with hot air at a temperature of 80°C for a preferred duration of 5 minutes minimum; evacuation of the hot air from chamber 4 and separation of the eradicated insect pests and the treated cereals.

[0059] Alternatively, this cycle for treating cereals with hot air can be as follows: partial vacuuming of chamber 4 to remove insect pests from the contaminated cereals, with mixing of the mass of cereals previously placed in chamber 4; returning chamber 4 to atmospheric pressure by drawing in hot air at a preferred temperature of 50 °C, then maintaining the mass of cereals at a temperature of 50 °C; returning chamber 4 to maximum vacuum at approximately 20 millibars, allowing the water of constitution of any larvae and eggs still included in the cereals to boil, thus eradicating them; evacuation of the hot air from chamber 4 and separation of the eradicated insect pests and the treated cereals.

[0060] For these two alternatives of the hot air grain treatment cycle, the hot air evacuated from the enclosure can be cooled, the cooled air can either be released into the atmosphere or reinjected into the enclosure for cooling the treated grains, before their extraction from enclosure 4.

[0061] Of course, the hot air treatment cycles can be repeated several times if necessary, before emptying the treated grain from chamber 4. In addition, the steps of conveying grain into chamber 4 and separating the treated grain from the eradicated insect pests will always be carried out.

[0062] Figures 9 and 10 illustrate a variant of installation 1, which includes several reactors 3, each defining a containment chamber 4a, 4b, 4c. In these figures, three reactors 3 are shown, but this number could be greater than three, or even as few as two. The presence of several reactors 3 advantageously increases the processing rate of grain infected with the harmful gaseous fluid. In particular, the presence of three reactors 3 advantageously allows one of the three chambers 4a, 4b, 4c to be filled while grain is being treated in a second of the three chambers 4a, 4b, 4c, and while already treated grain is being unloaded from a third of the three chambers 4a, 4b, 4c. Preferably, the vacuum device 2, the injection device 5 and the extraction device 15 will be common for these three enclosures 4a, 4b, 4c, as illustrated in Figure 9.Similarly, as illustrated in Figure 10, the grain to be treated is conveyed to one of the three chambers 4a, 4b, 4c by a conveying system 57, which could be, for example, a conveyor belt or a screw conveyor. The treated grain, once extracted from one of the three chambers 4a, 4b, 4c, is removed by a discharge system 58, which could be, for example, a conveyor belt or a screw conveyor. In Figure 10, the reactors 3 correspond, for example, to the one illustrated in Figure 4. Each reactor 3 includes a discharge device 41a, 41b, 41c for transferring the eradicated insect pests to another discharge system 59 common to the three reactors 3, which could be, for example, a conveyor belt or a screw conveyor.In this figure 10: the inlet gate 31a is open and the outlet gate 33a is closed (schematic closure by a cross) on the enclosure 4a of the first reactor 3 which is being loaded (schematically by arrow 60) with infected cereals to be treated; the inlet gate 31b is closed (schematic closure by a cross) and the outlet gate 33b is closed (schematic closure by a cross) on the enclosure 4b of the second reactor 3 which is carrying out a treatment on infected cereals, with harmful gaseous fluid being injected into the enclosure (schematically by arrow 61); and the entry gate 31c is closed (closure schematically represented by a cross) and the exit gate 33c is open onto the enclosure 4c of the third reactor 3 which is being unloaded with treated cereals (schematized by arrow 62) and the eradicated pest insects are being removed (schematized by arrow 63).

[0063] Thus, the installation 1 and the disinsection process, which are the subject of the invention, advantageously allow for the near-total extraction of all insects embedded in cereal grains before eradicating them using a harmful gaseous fluid, thus enabling the easy separation of the treated cereals from the eradicated pests. Whereas prior art installations merely chemically treat the cereals and kill the insects embedded in the grains, no effective separation is possible.

Claims

Demands 1. Disinsection installation (1) for the eradication of insect pests present in cereals, characterized in that it comprises an enclosure (4) configured to receive cereals, a vacuum device (2) configured to create a vacuum in the enclosure (4) when the cereals are placed in said enclosure (4), an agitation device configured to move the cereals in the enclosure (4), an injection device (5) configured to inject into the enclosure (4) a gaseous fluid harmful to insect pests, said injection of the harmful gaseous fluid taking place after the vacuum has been created, an extraction device (15) configured to extract and neutralize the gaseous fluid present in the enclosure (4) and a separation device configured to separate the eradicated insect pests from the cereals after treatment with the gaseous fluid.

2. Disinsection installation (1) according to claim 1, in which the enclosure (4) comprises a drum (21) mounted to rotate about a horizontal axis and configured to receive and contain cereals, said installation (1) comprising a device for rotating the drum (21) about the horizontal axis to agitate the cereals in the drum (21).

3. Insect control installation (1) according to claim 2, in which the drum (21) has a contour wall (26) provided with perforations (29) configured to allow the passage of air and harmful gaseous fluid.

4. Insect control installation (1) according to claim 3, wherein the perforations (29) are configured to retain the grain within the enclosure and to allow the passage of pest insects after their eradication by means of the harmful gaseous fluid.

5. Disinsection installation (1) according to any one of claims 2 to 4, wherein the drum (21) includes an access hatch (37) configured for inserting the grain to be treated into said drum (21) and an extraction hatch (38) configured for evacuating the grain after treatment and separation of the eradicated pest insects.

6. Insect control installation (1) according to any one of claims 2 to 5, wherein the enclosure (4) comprises a chamber (20) configured to contain the drum (21), the chamber (20) being configured to be sealed, the vacuum device (2) comprising a vacuum pump (14) connected to the chamber (20) to remove the air from said chamber (20).

7. Insect control installation (1) according to claim 6, wherein the chamber (20) comprises an entrance door (31) configured to open or close tightly the chamber (20), said inlet door (31) allowing the insertion into the enclosure (4) of the cereals to be treated and an outlet door (33) configured to open or close the chamber (20) in a sealed manner, said outlet door (33) allowing the extraction of the cereals from the enclosure after treatment.

8. Insect control installation (1) according to claim 7, wherein the chamber (20) includes another exit door (35) configured to open or close the chamber (20) hermetically, said other exit door (35) allowing the extraction of the eradicated pest insects from the enclosure (4).

9. Disinsection installation (1) according to any one of claims 1 to 8, which includes a grain conveying and evacuation device configured to insert grain to be treated into the enclosure (4) and to evacuate from the enclosure the treated grain separated from the eradicated insects.

10. Disinsection installation (1) according to any one of claims 1 to 9, which includes a device for removing eradicated pest insects after their separation from the cereals.

11. Insect control installation (1) according to any one of claims 1 to 10, wherein the injection device (5) comprises an ozone production system (6), the harmful gaseous fluid being ozone.

12. Insect control installation (1) according to claim 11, wherein the extraction device (15) comprises a suction system (16) configured to suction the ozone contained in the enclosure (4) and a catalyst (17) configured to neutralize the ozone suctioned from the enclosure (4).

13. Insect control installation (1) according to any one of claims 1 to 10, wherein the injection device (5) comprises a hot air production system (52), the harmful gaseous fluid being hot air.

14. Insect control installation (1) according to any one of claims 1 to 13, wherein the vacuum device (2) comprises a vacuum pump (14).

15. Insect control installation (1) according to claim 14, wherein the vacuum device (2) additionally comprises a steam ejector (47) and a boiler (48).

16. A process for the disinfestation of cereals, characterized in that it comprises the following steps: conveying cereals into an enclosure (4); creating a vacuum in the enclosure (4); injecting a harmful gaseous fluid into the enclosure (4); agitate the cereals in the enclosure (4); extract the harmful gaseous fluid from the enclosure (4) after treatment of the cereals and eradication of the insect pests and neutralize said harmful gaseous fluid extracted from the enclosure (4); - separate the treated cereals from the eradicated insect pests.

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