AU2018333842A1

AU2018333842A1 - A phosphene gas fumigation system, rectangular prism shaped aluminium phosphate charge, applicator and storage magazine therefor

Info

Publication number: AU2018333842A1
Application number: AU2018333842A
Authority: AU
Inventors: Roger Carrigan
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-09-15
Filing date: 2018-09-14
Publication date: 2020-03-26
Also published as: WO2019051552A1

Abstract

A phosphene gas fumigation system may comprise an Aluminium Phosphide rectangular prism charge, storage magazine and/or applicator which may address problems of user safety, correct application rates, flammability, volumetric efficiencies and/or commercial viability. The present Aluminum Phosphide charges are rectangular prism shaped, so as to prevent their rolling about and dangerously stacking together in use. Furthermore, the present applicator holds the charges immobile and apart. Wire mesh cages expose the charges to air and may flex to accommodate the charges which may expand while reacting. The charges and entrance ports of the applicator may be sized to prevent use of conventionally sized charges. The applicator may safely collect residue therein. Furthermore, the present storage magazine conveniently stores and loads and ejects charges and minimises air spacing therein, thereby reducing risk of flashback ignition.

Description

A phosphene gas fumigation system, rectangular prism shaped

Aluminium Phosphate charge, applicator and storage magazine therefor

Field of the Invention [1] This invention relates generally to a phosphene gas fumigation system comprising a rectangular prism shaped Aluminium Phosphate charge, applicator and storage magazine for storage infrastructure of commodities for rodent and insect control.

Background of the Invention [2] Aluminium Phosphide is a highly toxic inorganic compound that once exposed to atmospheric conditions will breakdown to Hydrogen Phosphide (phosphine or PH3).

[3] The gas is produced by a reaction with Aluminium phosphide in contact with moisture, even at ambient humidity levels. Phosphine gas is also highly toxic and flammable.

[4] Aluminium Phosphide is currently available in differently shaped pellets and powders. The most form is common takes the form either of a round marble like sphere or a round flat tablet shape having an average diameter of 16.5 mm diameter.

[5] However, the currently available shapes of Aluminium Phosphide are problematic in the application thereof.

[6] In the case of cereal grain commodity applications, one 16.5mm spherical tablet typically weighs 3 grams and contains lmg of Phosphine (PH3). The application rate is 1.5gms of Phosphine/m³ or 3 tablets per 2m³.

[7] The tablet is typically used in two application methods. A first application method may comprise application to grain as it is being augured into a sealed silo for storage, making it almost impossible to achieve the correct application rate to the moving commodity.

[8] This method can result in an over application of PH3 and most often leaves unacceptable residue levels in the commodity, or under application which can leave target species still alive and create resistance strains of insects. Both examples can result in significant financial losses.

[9] A second method may comprise suspending a flat tray from the ceiling of the silo having tablets/pellets thereon once the storage infrastructure has been filled and the tonnage of contents is better able to be estimated.

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PCT/AU2018/051001 [10] The issue however with this second method is that when the tray is being lowered inside the infrastructure, the contacting tablets may spontaneously combust. Additionally, burnt product may result in under application of PH3.

[11] Whilst this second method is very dangerous, it is still very common today.

[12] Moreover, current methods suffer from problems of the flammability of the PH3 Gas. Specifically, exothermically generated heat from tablets in close contact may be able to ignite the PH3 gas being generated.

[13] Indeed, Aluminium Phosphide tablets are commonly packaged in sealed cylindrical canisters which may result in a common phenomenon referred to within the industry as 'flash'.

[14] Flash is caused by the inrush of oxygen into the PH3 saturated unoccupied spacing between the Aluminium Phosphide spheres (the reaction causes a vacuum within the container) which can eject a sudden flash of flame, sometimes burning the handler, being particularly dangerous for a person being atop a 20 meter of higher silo.

[15] The present invention seeks to provide a way that will overcome or substantially ameliorate at least some of the deficiencies of the prior art, or to at least provide an alternative.

[16] It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country.

Summary of the Disclosure [17] There is provided herein a phosphene gas fumigation system comprising an Aluminium Phosphide rectangular prism charge, storage magazine and applicator which addresses problems of user safety, correct application rates, flammability, volumetric efficiencies and/or commercial viability or at least provides an alternative.

[18] The charge comprises a rectangular prism shape which addresses the multiple flaws of the current shaped pellets and tables available on the market.

[19] Specifically, conventional spherical shaped Aluminium Phosphide tablets have the ability to travel/rolI and bunch up on top of each other and therefore pose a risk of ignition.

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PCT/AU2018/051001 [20] The present charge however has a rectangular prism shape, which once inserted into the present applicator is immobile, unless the applicator is inverted upside down. Additionally, the shape of the present rectangular prism shaped charges reduces the likelihood of their rolling when been handled or stored.

[21] Within the applicator, as the rectangular prism charge breaks down, no part of the charge comes into contact with adjacent charges.

[22] Furthermore, by-product falls to the bottom of the applicator and by-product is unlikely to ignite.

[23] The by-product typically contains 2% - 3% unreacted Aluminium Phosphide in the byproduct. However, this small amount of active ingredient is stabilized in the crystalline lattice of the waste. As such, the by-product has very low oral and dermal toxicity and is not a significant fire hazard. Furthermore, spent and partially spent dust are rather dense and ordinarily do not represent an inhalation hazard.

[24] Furthermore, the present rectangular prism charge is 1.2cm x 1.2cm x 8.2cm in a preferred embodiment and therefore has a 11.80cm³volumetric area.

[25] As there is an average of lmg of PH3 gas per 2.35cm3, each rectangular prism therefore contains an average of 5.02mg of PH3 gas.

[26] Furthermore, wheat has a bulk density of 750kg-850kg/m3 and each m³ requires 1.5mg of PH3 for a successful fumigation.

[27] As such, a rectangular prism charge is able to treat approximately 2.5T of grain.

[28] The rectangular prism shape of the present charge allows the charge to be inserted into square entrance ports atop the present applicator.

[29] Inside each port the present applicator comprises a shaped 5x5mm wire mesh holding basket to subject the charge to atmospheric conditions, even while expanding slightly when reacting. This allows the user the ability to load and place the correct amount of charges into the applicator and to hang the applicator from the ceiling of a silo with the charges being immobilised as compared to the prior art spherical charges which are able to roll against each other, contacting and bunching up, causing ignition or an under applied rate of fumigation.

[30] A 1.65cm diameter spherical product has a volume of 2.35cm³ and a 1.65cm cube equivalent has a volume of 4.49cm³.

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PCT/AU2018/051001 [31] Furthermore, each charge 1 comprises a length of approximately 82 mm. Therefore, the prism shape of the charge 1 may represent a 47% increased area efficiency available for packaging and transportation and application.

[32] The present storage magazine was developed to safely store the charge and to protect the user from 'flash'. The shape of the charge and the corresponding interior shape of the storage magazine restricts unoccupied space within the storage magazine which would otherwise cause flash.

[33] The magazine also reduces the Aluminium Phosphide application time and requires handling only of charges required for the specified dosage.

[34] The storage magazine may be made from aluminium or tin and may hold up to 5 rectangular prism charges, enough to treat 12.5T of wheat.

[35] The storage magazine may be spring loaded to push rectangular prism charges to the exit.

[36] The magazine cap may be made of a heavy single moulded plastic that can seal to the holding canister by a series of five rubber finned gaskets moulded to the inside of the cap. Once the cap is forced onto the magazine, an airtight seal around the storage magazine is achieved and is held in place by locking clips on the top and the bottom of the unit.

[37] The applicator has been designed to overcome the hazard of round or flat shaped Aluminium Phosphide products having the ability to bunch up around each other during application, and either not being able to break down properly, causing an under application rate of PH3 gas, or igniting the remaining flammable PH3 gas which can also result in an under application as well as the loss and destruction of commodities and infrastructure. The applicator also allows for the correct application rate and minimal exposure to the charges during application.

[38] The applicator may be made out of thin tin for structural integrity, resistance against fire and manufacturing affordability.

[39] The top of the applicator may have up to 60 x 1.5cm x 1.5cm square ports for receipt of the 1.2cm x 1.2cm x 8.2cm rectangular prism charges.

[40] Each holding basket may hold two rectangular prism charges at one time in line.

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PCT/AU2018/051001 [41] Furthermore, the restriction of the entrance port sizing to 1.5cm x 1.5cm prevents users from trying to insert the commonly available 1.65cm diameter spherical tablets into the applicator.

[42] Each entrance port of the applicator leads to a 5mm x 5mm square wire mesh rectangular prism holding basket to hold the rectangular prism charge securely in place as the Aluminium Phosphide breaks down to Aluminium Phosphine gas (PH3).

[43] The by-product of the rectangular prism charge breaks down through the sides of the mesh holding basket and is held in a gap at the bottom of the applicator as waste.

[44] On each corner of the applicator may have apertures for attachment of D-shackle suspension chain to attach/suspend the applicator from the ceiling of the infrastructure (if required). Suspending the applicator to the ceiling of infrastructure will prevent the applicator from being (in the case of a grain silo) dragged down through the grain to the bottom of the silo whilst the silo is being emptied.

[45] Suspension of the applicator also enables the user to retrieve the applicator after fumigation is complete to re-use.

[46] According to one aspect, there is provided a phosphene gas fumigation system comprising: a plurality of Aluminium Phosphate charges, each charge having a rectangular prism shape; and an applicator, the applicator comprising an upper surface comprising a plurality of entrance ports each leading to rectangular prism shaped mesh charge engagement baskets such that, in use, at least one charge may be inserted lengthwise into a respective entrance port to expose the charge to air within the applicator.

[47] The rectangular prism may have a width, breadth and length and wherein the width and breadth may be less than 16 mm.

[48] The width and breadth of the rectangular prism may be each approximately 12 mm.

[49] The length of the rectangular prism may be approximately 82 mm.

[50] The wire mesh charge engagement baskets may be spaced apart from each other.

[51] The width may be less than 16 mm.

[52] The width and the breadth may be each approximately 15 mm.

[53] The applicator may comprise greater than 50 entrance ports and charge engagement baskets.

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PCT/AU2018/051001 [54] The applicator may comprise 60 entrance ports and mesh charge engagement baskets.

[55] The applicator may comprise a body having a floor and wherein byproduct falling from the charge engagement baskets collects on the floor in use.

[56] The body may comprise suspension chain apertures for suspension of the applicator in use.

[57] Side walls of the body may comprise vents.

[58] The vents may be located above and away from the floor.

[59] The system may further comprise a storage magazine, and the storage magazine may comprise a container for the charges, the container having a width, breadth and depth; and the container may be configured for reducing unoccupied volume within the container in that the width and breadth of the container may be configured according to the respective dimensions of the plurality of Aluminium Phosphate charges therein.

[60] The depth may be configured for the storage of 5 adjacently stacked charges.

[61] The container may define an entrance and may further comprise a midway located entrance sleeve open at either end for the lateral insertion and removal of the charges.

[62] The system may further comprise a biasing spring for pushing the charges towards the entrance sleeve.

[63] The system mayfurthercomprise airtight gasketing between the lid and the container.

[64] According to another aspect, there is provided an Aluminium Phosphate charge for phosphine gas fumigation, the charge having a rectangular prism shape.

[65] The rectangular prism may have a width and breadth each less than 16 mm.

[66] The width and breadth may be each approximately 12 mm.

[67] The length may be approximately 82 mm.

[68] According to another aspect, there is provided an applicator for phosphine gas fumigation, the applicator comprising an upper surface comprising a plurality of entrance ports for a respective plurality of rectangular prism shaped mesh charge engagement baskets.

[69] The mesh charge engagement baskets may be spaced apart from each other.

[70] Each entrance port may comprise a cross-section having a width and a breadth less than 16 mm.

[71] The width and the breadth may be each approximately 15 mm.

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PCT/AU2018/051001 [72] The applicator may comprise greater than 50 entrance ports and respective mesh charge engagement baskets.

[73] The applicator may comprise 60 entrance ports and respective mesh charge engagement baskets.

[74] The applicator may comprise a body having a floor and wherein byproduct falling from the wire mesh charge engagement baskets collects on the floor in use.

[75] The body may comprise suspension chain apertures for suspension of the applicator in use.

[76] Side walls of the body comprise vents.

[77] The vents may be located above and away from the floor.

[78] According to another aspect, there is provided a storage magazine for rectangular prism shaped Aluminium Phosphate charges, the storage magazine comprising: a container for the charges, the container having a width, breadth and depth; and a lid for closing off the container and wherein the container is configured for reducing unoccupied volume within the container in that the width and breadth of the container are configured according to the respective dimensions of the prism shaped Phosphate charges therein.

[79] The depth may be configured for the storage of 5 adjacently stacked charges.

[80] The container defines an entrance and further comprising a midway located entrance sleeve open at either end for the lateral insertion and removal of charges.

[81] The storage magazine may further comprise a biasing spring for pushing the charges towards the entrance sleeve.

[82] The storage magazine may further comprise airtight gasketing between the lid and the container.

[83] Other aspects of the invention are also disclosed.

Brief Description of the Drawings [84] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:

[85] Figure 1 shows a plurality of adjacently stacked rectangular prism shaped Aluminium Phosphate charges in accordance with an embodiment;

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PCT/AU2018/051001 [86] Figure 2 shows a storage magazine for the rectangular prism shaped Phosphate charges in accordance with an embodiment;

[87] Figure 3 shows a plurality of Aluminium Phosphate charges located within the storage magazine;

[88] Figure 4 shows an applicator for the prism shaped Aluminium Phosphate charges in accordance with an embodiment; and [89] Figure 5 shows an interior view of the applicator.

Description of Embodiments [90] Figure 1 shows a plurality of adjacent rectangular prism shaped Aluminium Phosphate charges 1.

[91] The charges 1 are rectangular prism shaped so as to prevent their rolling about and bunching up upon each other as do the spherical or annular shaped prior art arrangements, thereby reducing the likelihood of the aforedescribed problems of spontaneous combustion, inadequate location and the like. Other shaped charges 1 that prevent or minimise rolling about are envisaged within the scope of other embodiments such as charges having trianglar cross-sections and the like.

[92] Preferably, each charge 1 comprises a width, breadth and length and wherein the width and breadth are approximately 12 mm, being less than the 16.5 mm diameter of commonly available spherical or annular Aluminium Phosphate charges.

[93] In this way, the charges 1 may be inserted into the approximately 15 mm² entrance port of the applicator 9 as is substantially shown in Figures 4 and 5 whereas the prior art 16.5 mm diameter spherical or annular Aluminium Phosphate charges cannot.

[94] Figure 4 shows an applicator 9 for housing of the charges 1 during fumigation. The applicator 9 may comprise an upper surface comprising a plurality of entrance ports 11. As alluded to above, each entrance port 11 may be approximately 15 mm² so as to allow the insertion of the approximately 12mm² cross-sections of the charges 1.

[95] Figure 5 shows an interior view of the applicator 9 wherein beneath each entrance port 11 is a rectangular wire mesh retention basket 14.

[96] Each wire mesh retention basket 14 securely holds a respective charge 1 having been inserted through the entrance ports 11 and exposes the charge 1 to air.

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PCT/AU2018/051001 [97] Furthermore, the retention baskets 14 are spaced away from each other so as to prevent contact between the charges 1. In embodiments, each retention basket 14 may be spaced away from each adjacent retention basket 14 by 10 mm or more.

[98] The wire mesh of the retention baskets 14 may expand to accommodate the swelling of the charges 1 when reacting.

[99] Each retention basket 14 may comprise a length of approximately 160 mm or greater so as to accommodate at least two charges 1 in line.

[100] Byproduct falls from the retention baskets 14 to the floor of the applicator 9.

[101] The side walls of the applicator 9 may comprise vents 13 for escape of phosphine gas therefrom. The vents 13 may be located away from the floor of the applicator 9 so as to prevent byproduct escaping therefrom.

[102] Accommodation apertures 12 may be provided for the securement of suspension chains thereto.

[103] Figure 2 shows a storage magazine 2 for the Aluminium Phosphate rectangular prism shaped charges 1.

[104] The storage magazine 2 comprises a storage compartment 4 and a lid 3.

[105] The storage compartment 4 may be substantially rectangular so as to be able to accommodate a plurality of adjacently stacked charges 1 as a substantially shown in figure 3.

[106] As such, the storage compartment 4 may have a breadth of approximately 15 mm and a width of approximately 85 mm so as to be able to accommodate the lengthwise crosssection of the charges 1 while minimising unoccupied space.

[107] Furthermore, the storage compartment 4 may comprise a depth sufficient to store up to 5 charges.

[108] The storage compartment 4 may comprise an entrance retention sleeve 6 closing off the entrance.

[109] The configuration of the entrance retention sleeve 6 allows the lateral insertion and removal of charges 1 and prevents charges 1 from falling feely from the container 4.

[110] The magazine 2 may comprise a biasing spring 8 which pushes the charges 1 towards the entrance retention sleeve 6.

[111] As such, as a charge 1 is pushed laterally from the sleeve 1 into an entrance port 11 of the applicator, the next adjacent charge 1 is pushed by the biasing spring 8 into the sleeve 6.

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PCT/AU2018/051001 [112] The lid 3 and the compartment 4 may comprise interlocks 6 which are shown as complimentary arrowhead bosses 5 in figure 2.

[113] The interior of the lid 3 may comprise sealing gaskets 7 for air tightness.

[114] In embodiments, the compartment 4 may be manufactured from tin and the lid 3 from plastic.

[115] The container 4 may be configured for storing five charges therein, including within the sleeve 6 such that, when the lid 3 is located of the container 4, unoccupied area is minimised.

[116] The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required in order to practice the invention. Thus, the foregoing descriptions of specific embodiments of the invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed; obviously, many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, they thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the following claims and their equivalents define the scope of the invention.

Claims

Claims

1. A phosphene gas fumigation system comprising:

a plurality of Aluminium Phosphate charges, each charge having a rectangular prism shape; and an applicator, the applicator comprising an upper surface comprising a plurality of entrance ports each leading to rectangular prism shaped mesh charge engagement baskets such that, in use, at least one charge may be inserted lengthwise into a respective entrance port to expose the charge to air within the applicator.
2. A system as claimed in claim 1, wherein the rectangular prism has a width, breadth and length and wherein the width and breadth are less than 16 mm.
3. A system as claimed in claim 2, wherein the width and breadth of the rectangular prism are each approximately 12 mm.
4. A system as claimed in claim 1, wherein the length of the rectangular prism is approximately 82 mm.
5. A system as claimed in claim 1, wherein the wire mesh charge engagement baskets are spaced apart from each other.
6. A system as claimed in claim 1, wherein each entrance port comprises a crosssection having a width and a breadth and wherein the width is less than 16 mm.
7. A system as claimed in claim 6, wherein the width and the breadth are each approximately 15 mm.
8. A system as claimed in claim 1, wherein the applicator comprises greater than 50 entrance ports and charge engagement baskets.
9. A system as claimed in claim 8, wherein the applicator comprises 60 entrance ports and mesh charge engagement baskets.
10. A system as claimed in claim 1, wherein the applicator comprises a body having a floor and wherein byproduct falling from the charge engagement baskets collects on the floor in use.
11. A system as claimed in claim 10, wherein the body comprises suspension chain apertures for suspension of the applicator in use.
12. A system as claimed in claim 10, wherein side walls of the body comprises vents.

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13. A system as claimed in claim 12, wherein the vents are located above and away from the floor.
14. A system as claimed in claim 1, further comprising a storage magazine, the storage magazine comprising:

a container for the charges, the container having a width, breadth and depth; and a lid for closing off the container and wherein the container is configured for reducing unoccupied volume within the container in that the width and breadth of the container are configured according to the respective dimensions of the plurality of Aluminium Phosphate charges therein.
15. A system as claimed in claim 14, wherein the depth is configured for the storage of 5 adjacently stacked charges.
16. A system as claimed in claim 14, wherein the container defines an entrance and further comprising a midway located entrance sleeve open at either end for the lateral insertion and removal of the charges.
17. A system as claimed in claim 16, further comprising a biasing spring for pushing the charges towards the entrance sleeve.
18. A system as claimed in claim 14, further comprising airtight gasketing between the lid and the container.
19. An Aluminium Phosphate charge for phosphine gas fumigation, the charge having a rectangular prism shape, wherein the rectangular prism has a width, breadth and length and wherein the width and breadth are less than 16 mm.
20. A charge as claimed in claim 19, wherein the width and breadth are each approximately 12 mm.
21. A charge as claimed in claim 19, wherein the length is approximately 82 mm.
22. An applicator for phosphine gas fumigation, the applicator comprising an upper surface comprising a plurality of entrance ports for a respective plurality of rectangular prism shaped mesh charge engagement baskets.
23. An applicator as claimed in claim 22, wherein the mesh charge engagement baskets are spaced apart from each other.
24. An applicator as claimed in claim 22, wherein each entrance port comprises a crosssection having a width and a breadth less than 16 mm.

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25. An applicator as claimed in claim 24, wherein the width and the breadth are each approximately 15 mm.
26. An applicator as claimed in claim 22, wherein the applicator comprises greater than 50 entrance ports and respective mesh charge engagement baskets.
27. An applicator as claimed in claim 26, wherein the applicator comprises 60 entrance ports and respective mesh charge engagement baskets.
28. An applicator as claimed in claim 22, wherein the applicator comprises a body having a floor and wherein byproduct falling from the wire mesh charge engagement baskets collects on the floor in use.
29. An applicator as claimed in claim 28, wherein the body comprises suspension chain apertures for suspension of the applicator in use.
30. An applicator as claimed in claim 28, wherein side walls of the body comprise vents.
31. An applicator as claimed in claim 30, wherein the vents are located above and away from the floor.
32. A storage magazine for rectangular prism shaped Aluminium Phosphate charges, the storage magazine comprising:

a container for the charges, the container having a width, breadth and depth; and a lid for closing off the container and wherein the container is configured for reducing unoccupied volume within the container in that the width and breadth of the container are configured according to the respective dimensions of the prism shaped Phosphate charges therein.
33. A storage magazine as claimed in claim 32, wherein the depth is configured for the storage of 5 adjacently stacked charges.
34. A storage magazine as claimed in claim 32, wherein the container defines an entrance and further comprising a midway located entrance sleeve open at either end for the lateral insertion and removal of charges.
35. A storage magazine as claimed in claim 34, further comprising a biasing spring for pushing the charges towards the entrance sleeve.
36. A storage magazine as claimed in claim 32, further comprising airtight gasketing between the lid and the container.