GB2615288A

GB2615288A - Oxidising system

Info

Publication number: GB2615288A
Application number: GB2111671.0A
Authority: GB
Inventors: Shamus Sullivan Jonathan
Original assignee: O3biotech Ltd
Current assignee: O3biotech Ltd
Priority date: 2021-08-13
Filing date: 2021-08-13
Publication date: 2023-08-09
Anticipated expiration: 2041-08-13
Also published as: WO2023017496A1; GB2615288B; GB202111671D0

Abstract

A system for oxidising a granular organic material comprising a vessel having baffle(s) 12 that disrupt the material falling from an inlet towards an outlet. A pressurised supply of ozone gas passes through mixer 46 aperture(s). The baffle(s) may have aperture(s) 36 in a surface. Preferably, the mixer is an auger or Archimedean screw and is part of the baffle(s). The baffle(s) may be parabola-shaped and have moveable portions driven by a motor. Preferably, pairs of baffles direct the material towards the auger. The system may comprise a gas joint connector that has a dual lip seal to prevent leakage from the port. Preferably a level sensor connects to a controller for opening and shutting the inlet. Preferably, a cyclone removes particles smaller than 400 μm. There may be an agitating plate and a vertical re-circulator 56 with an auger that transports material from the outlet to the inlet of the vessel, which may be a silo. There may be a blast panel 70. Also claimed is a method and a system that is deployed between a grain store and animal feeding system.

Description

OXIDISING SYSTEM

Field

The present invention provides a system for oxidising a granular organic material, and a method of oxidising a granular organic material.

Background

Grain, feedstock and other granular organic material is prone to adulteration by fungal and bacterial growth. Often such granular organic materials are high value, and they are intended for use in human or animal food supply chains. Therefore, damage to a bulk store of such granular organic materials can result in significant financial losses to a manufacturer, supplier or farmer, as well as disruption to a supply chain for important feedstock for human or animal consumption.

There is therefore a need to maintain strict standards of hygiene throughout all stages of material handling, processing and in storage systems for granular organic materials.

There is a particular need to maintain granular organic materials dry and within specific temperature ranges in order to prevent bacterial or fungal growth which can spoil the granular organic materials. Often food grains obtained by harvesting crops, such as wheat, are dried in sunshine before storing to reduce their moisture content.

The higher the moisture content in food grains tends to promote the growth of fungi and moulds on the stored grains which damages them. Therefore, as well as drying, it is often necessary to treat such granular organic materials further in order to prevent them from spoiling.

There is therefore a need for a system, and a method, capable of efficiently treating granular organic materials in order to prevent them from spoiling.

Prior Art

Canadian patent application CA 2 980 091 (ETIA) discloses a method for the continuous treatment of a product in the form of particulate solids, comprising the steps of: introducing the product into a chamber with a pressurised ozone atmosphere; conveying the product through the chamber in a continuous movement such that the product is continuously in the ozone atmosphere as it is being conveyed through the chamber. The product is conveyed by means of a screw conveyor mounted to rotate in the chamber about a given axis. Treated product is ejected from the chamber through an outlet after it has passed once through the chamber.

European patent 2 785 474 (Association de Gestion de l'Institut Polytechnique) discloses a system which uses of ozone for the elimination of persistent phytosanitary molecules contained in plant seeds. Plant seeds contaminated with persistent phytosanitary molecules are treated in a process which comprises: providing plant seeds contaminated with persistent phytosanitary molecules into an atmosphere whose humidity is adjusted from at least 10% and at most 21% with respect to the dry matter.

The contaminated plant seeds are then brought into contact with ozone and residual ozone is then evacuated. The treated plant seed may be wheat, corn or rape seed.

FR 2 811 745 (ETIA Evaluation Technologique) describes a method of refrigerating particulate solids which involves convectively permanently cooling the centre of mass of particulate on a cold wall which extends in a conveying direction. The mass is simultaneously subjected to a through flow of a cooling gas to fluidize it without use of a condenser. The gas also increases the heat exchange rate of the cold wall.

US 2011/0151080 (Kevin Johnson) describes a system for treatment of grain in a storage container using ozone. The system treats grain for toxins, insects, mould, and/or odour. Downdraft methods apply high concentrations of ozone to grain in a storage container without generating ozone-related objectionable odours or with generation of only minimal ozone-related objectionable odours.

The method involves providing a negative air pressure at a bottom of a volume of grain in a storage container. A high ozone concentration is generated in air above an upper surface of the volume of grain. The ozone is drawn down into the volume of grain using the negative air pressure for a treatment time sufficient to effectively treat the grain without causing significant ozone-related commercially-objectionable foreign odours in the grain.

It is apparent therefore that there is a need for an improved system which treats grain or granular materials, such as feedstuff for livestock, in an efficient manner in order to remove contaminants.

The invention arose in order to overcome problems associated with existing oxidation systems.

Summary of the Invention

According to a first aspect of the present invention, there is provided a system for oxidising a granular organic material comprising: a processing vessel having an upper end and an opposed lower end, in which the vessel comprises an inlet which is located at the upper end of the vessel, the inlet is configured to supply material from a delivery system to the vessel, and an outlet which is located at the lower end of the vessel; at least one baffle is provided within the vessel, the at least one baffle being dimensioned and arranged to disrupt the passage of the material falling from the inlet towards an outlet; and a pressurised supply of ozone gas is configured to pass ozone gas through at least one mixer aperture of the at least one mixer to oxidise the material.

The term baffle includes anything which mixes, promotes mixing, causes a disturbance or disruption in a flow of the granular organic material and includes any device which maximises a contact area as a consequence of agitation and/or fluidisation and/or disruption of flow of the granular organic material within the silo.

Optionally the at least one mixer is formed integrally with the, or each, baffle. In some embodiments the at least one baffle has a plurality of apertures defined in at least a part of its surface through which granular organic material passes or is directed.

The, or each, mixer preferably comprises an auger or Archimedean screw which rotates about an axis.

In some embodiments the baffles are separate from the mixer and are arranged symmetrically either side of the axis.

In some embodiments the baffles are supported on hinges and are adapted to be raised and lowered, tipping up or down about the axis, within the vessel so that the angle they enclose either side of the axis is variable. Baffles may be moved independently one from another or they may be connected so that they move together. Variation of the angle of inclination of baffles causes a pathway to be opened or closed between their edges and walls of the silo. This feature may be used to vary internal characterises such as pressure differentials or the amount of fluidisation that is achieved when treating the material.

Also the fact that the baffles are capable of being raised to a steeper angle, reduces the effective friction presented by their surfaces. This configuration may be adopted when the system is used to treat lighter materials. In addition the baffles may be lowered when the system is used to treat denser materials, or those with a different flowability, for example.

In a preferred embodiment of the system an auger is disposed along the axis and is operative to introduce ozone gas into the bulk of material as it falls towards the outlet and as material is guided by baffles. Ideally a suitable space is defined between linear edges of two baffles either side of the auger.

Ideally the baffles are shaped as pairs of parabolic sheets which are disposed at an angle within the body of the silo to resemble a pair of butterfly wings.

In another embodiment, baffles may include a hollow portion through which ozone gas passes and is delivered to an array of small holes formed in the baffle wall leading from its outer surface (skin) to its hollow portion. These holes allow injection of a pressurised gas mix, which ideally includes a proportion of ozone, in order to agitate the granular material as it passes over the external outer surface of the baffle and to expose the material to ozone. When the gas is introduced under pressure, mixing of the granular material also occurs.

Optionally the gas mixture may be warmed in order to promote drying.

The material is preferably organic material, for example granular organic material, such as grain, flour or human or animal feedstuff.

In one embodiment, the vessel comprises a closable outlet providing a discharge point for removing material from the vessel, through which treated material passes for immediate use, for storage or for recirculation.

The system may further comprise a vertical re-circulator or a cyclone, configured to collect and transport material from the outlet of the vessel to the inlet of the vessel.

In a preferred embodiment the combined features of agitation, drying and oxidation help to avoid flocculation of the granular organic material.

In one embodiment, a vertical re-circulator comprises a first end providing an inlet in communication with the outlet of the vessel, and a second opposed end providing an outlet in communication with inlet of the vessel.

Treated material is ideally removed from the vessel, via the outlet, and optionally via the vertical re-circulator and transported to the upper inlet, via the outlet of the vertical re-circulator.

The vertical re-circulator may include a blower, or a series of buckets or preferably a delivery system with a motor driven auger which receives material at its lower end and deposits the material at an upper inlet port.

The system preferably further comprises a drive means associated with the at least one baffle. The drive means is preferably configured to displace the baffle relative to the vessel. Displacement of the baffle, relative to the vessel, improves disruption of the passage of falling material within the vessel and thereby improves efficiency of mixing and exposure to gaseous treatment of the material.

Displacement of baffles may be achieved by application of vibration to the baffles or by raising or lowering portions of the baffles.

The drive means may include a motor associated with the at least one baffle. The drive means is preferably configured to rotate the at least one baffle with respect to the vessel.

In one embodiment, the system comprises a plurality of baffles within the vessel which direct and deflect the material to prevent material from falling vertically from the inlet to the outlet, thereby prolonging the dwell time that material is exposed to gaseous treatment.

Baffles may be movable by actuators which are controlled automatically by a drive means or by a human operator. The drive means may be associated with one or more of a plurality of baffles. In one embodiment, a separate drive means may be associated with each of the baffles.

Mixing may be improved by applying a pressurised fluid source, such as air or a mixture of air with at least one other gas, such as ozone.

The vessel may have any suitable shape and/or dimension. In one embodiment, the vessel comprises a frusto-conical section located at or adjacent the lower end of a generally cylindrical vessel. Typically the height of the vessel is in excess of 5 metres and preferably in excess of 10 metres.

The system may comprise a discharge agitator located at or adjacent the lower end of vessel and/or the outlet of the vessel.

In a preferred embodiment a gas joint connector has a flexible seal which accommodates movement between and resists shocks and vibration to ensure that ozone is delivered in a safe manner from an ozone supply to the silo without leakage.

Ozone gas is delivered via the connector to a static injection port and then to a mixing member, such as a rotating auger, without any loss of gas to the surroundings. This is important to avoid leakage of ozone to the environment which may be dangerous.

Ozone gas is delivered via hose and an injection port. The gas joint connection is ideally mounted on a bearing mounting housing. A dual lip seal ensures there is no ozone leakage.

In one embodiment, the system may comprise a discharge agitator comprising an actuator connected to a frusto-conical section of the vessel, and in which the agitator is displaced with respect to the vessel in a gyrating manner in order to prevent bridging of flowing material.

The discharge agitator may include a gyrator and/or agitator and/or auger which are operative to impose vibrations to moving granular material and are optimised to prevent blockages of treated material.

The system may further comprise at least one level sensor configured to detect a level of an amount of stored material within the vessel.

Systems ideally further comprise a processing means configured to receive a signal from the at least one level sensor, and a controller operative to modify supply of material to the inlet of the vessel in the event of the processing means detecting that the level of material within the vessel has reached a predetermined maximum level for the material.

The controller may be configured to receive a command signal from the processing means in dependence on the signal from the at least one level sensor.

The system may further comprise a cyclone for removing particles of material from the vessel. Preferably, the cyclone is operative to remove particles having a particle size less than a predetermined maximum level, for example the cyclone is configured to remove particles having a particle size of less than 400 pm, preferably less than 300 pm.

The system may further comprise a dehumidifier operative to extract moisture from within the vessel.

The system may further comprise at least one agitating plate located in the vessel operative to promote mixing of the material.

The system may further comprise at least one heat transfer means operative to extract heat from the material as it passes through the vessel.

The system may further comprise a monitoring system operative to sense and monitor at least once material characteristic of the material and/or an at least once vessel characteristic of an internal volume of the vessel.

In one embodiment, the monitoring system is operative to sense and monitor an amount of colony forming units (CFU/g) on non-oxidised and oxidised material.

The system may further comprise a control system operative to vary at least one of the following factors in dependence upon the material characteristic and/or the vessel characteristic, the factors from the group comprising: average particle size, mass flow of the material through the vessel, dwell time of the material in the vessel, concentration of ozone gas introduced into the vessel, moisture content of the material, humidity within the vessel, temperature of the vessel, temperature of the material exiting the vessel and amount of colony forming units (CFU/g) detected on a sample of the material.

According to a second aspect of the invention there is provided a system for oxidising a granular organic material, which is deployed between a silo/grain store in which a granular organic material is stored and an animal feeding system, the system comprising: a rotating auger supported in a hollow housing and a drive means which is operative to rotate the auger; a first end of the housing has a gas tight seal for connection to the silo/grain store and a second end of the housing has a gas tight seal for connection to the animal feeding system; an inlet port on the housing receives a supply of gas which includes ozone, and defines a gas tight pathway to a hollow interior section of the auger and holes formed in the auger allow passage of the gas to contact the granular organic material.

At least one sensor provides a signal to a processing means which is configured to operate a controller for modifying the drive means so as to alter the mass flow rate of supply of the granular organic material to the housing.

The system provides a 'retro-fit auger' which could be connected from a silo/grain store on a farm to a feed supply, for local use in treating animal feed.

According to a third aspect of the present invention, there is provided a method of oxidising a granular organic material comprising the steps of: introducing the material into a processing vessel; cascading the material over at least part of a surface of at least one baffle provided within the vessel; and passing ozone through at least one mixer aperture of the at least one mixer to oxidise the material as the material falls towards an outlet of the vessel.

Embodiments of the present invention will now be described in detail and with reference to the Figures in which:

Brief Description of Figures

Figure 1 is a schematic illustration of a system for oxidising a granular organic material according to one embodiment of the present invention; Figure 2 is a photograph of a portion of the system for oxidising a granular organic material of Figure 1; Figure 3 is a schematic illustration of an apparatus comprising a system for oxidising a granular organic material according to a further embodiment of the present invention; Figure 4 is a schematic illustration of a system for oxidising a granular organic material according to a further embodiment of the present invention; Figures 5 to 7 show side views of an alternative embodiment of a system for oxidising a granular organic material; Figure 8 shows a diagrammatical view of the system shown in Figures 5 to 7; Figures 9, 10 and 11 show overall, part sectional views of a silo depicting cross augurs and butterfly flaps; Figure 12 shows a view of a lower part of the silo which shows an exit port, with a gyrator and a recirculation valve; Figure 13 shows an overall view of a system which includes an embodiment of the processing vessel or silo, a bulk storage hopper or silo and a bag unloader; and Figure 14 is an overall sectional view through a gas joint connector. Detailed Description of Preferred Embodiments With reference to Figures 1 to 4, the system 1, 1' for oxidising a granular organic material comprises a processing vessel 2, 2'. The processing vessel 2, 2' has an upper end 4, 4' and an opposed lower end 6. 6'. The vessel 2, 2' comprises an inlet 8, 8' located at the upper end 4, 4' of the vessel 2, 2'.

It is to be understood that although the illustrated embodiment shows the inlet 8, 8' to be at the upper end 4,4' of the vessel 2, 2' that the inlet 8, 8' may be located at any location adjacent the upper end 4, 4' of the vessel 2, 2'. The inlet 8, 8' is configured to supply material from a delivery system to the vessel 2, 2'. The vessel 2, 2' further comprises an outlet 10, 10' located at the lower end 6, 6' of the vessel 2, 2'.

It is to be understood that although the illustrated embodiment shows the outlet 10, 10' to be at the lower end 6, 6' of the vessel 2, 2' that the outlet 10, 10' may be located at any location adjacent the lower end 6, 6' of the vessel 2, 2'.

The system 1, 1' further comprises a plurality of baffles 12, 12' provided within the vessel 2, 2'. The baffles 12, 12' are dimensioned and arranged to disrupt the passage of the material falling from the inlet 8 towards the outlet 10, 10'. Baffles 12, 12' are in the form of a butterfly wing and provides at least one aperture defined in a surface thereof.

The system 1, 1' further comprises a pressurised supply of ozone gas 14, 14' configured to pass through the apertures of each baffle 12, 12' to oxidise the granular organic material.

The outlet 10, 10' is closable and in communication with a vertical re-circulator 16, 16'. The outlet 10, 10' is operable to provide a discharge point for removing material from the vessel 2, 2' for storage, or for recirculation via the vertical re-circulator 16, 16'.

The vertical re-circulator 16, 16' is configured to collect and transport material from the outlet 10, 10' of the vessel 2, 2' to the inlet 8, 8' of the vessel 2, 2'. The vertical re-circulator 16, 16' has a first end 18, 18' providing an inlet 20, 20' in communication with the outlet 10, 10' of vessel 2, 2' and an opposed second end 22, 22' providing an outlet 24, 24' in communication with the inlet 8, 8' of the vessel 2, 2'. The vertical re-circulator 16, 16' includes a delivery system with a motor driven auger.

The system 1, 1' comprises a drive means (not shown) associated with each of the baffles. The drive means is configured to rotate the baffles 12, 12' relative to the vessel 2, 2' so as to improve disruption of the passage of the falling material and thereby improve efficiency of oxidation of the material.

The lower end of the vessel 2, 2' comprises a frusto-conical section 26, 26'. The system may comprise a frusto-conical section 26, 26' having any suitable shape and/or dimensions. The system 1, 1' further comprises a discharge agitator 28, 28' including a gyrator, located towards the lower end 6, 6' of vessel 2, 2'. The discharge agitator 28, 28' includes an actuator connected to a frusto-conical section 26, 26' of the vessel 2, 2' and in which the agitator 28, 28' is displaced with respect to the vessel 2, 2'.

The system 1, 1' further comprises a level sensor 30, 30' configured to detect a level of material within the vessel 2, 2'. The level sensor 30, 30' is located adjacent the upper end 4, 4' of the vessel 2, 2'.

The system 1, 1' further comprises a processing means (not shown) configured to receive a signal from the level sensor 30, 30' and a controller (not shown) operative to shut off supply of material to the inlet 8, 8' of the vessel in the event of the processing means detecting that the level of material within the vessel has reached a predetermined maximum level for the material.

The system 1, 1' further comprises three spaced apart agitating plates 32, 32' located in the vessel 2, 2' operative to promote mixing of the material.

The system 1, 1' further comprises a monitoring system (not shown) to sense and monitor an amount of colony forming units (CFU/g) on non-oxidised and oxidised material. The system 1, 1' also comprises a control system operative to vary at least one of the following factors in dependence upon the material characteristic and/or the vessel characteristic, the factors from the group comprising: average particle size, mass flow of the material through the vessel, dwell time of the material in the vessel, concentration of ozone gas introduced into the vessel, moisture content of the material, humidity within the vessel, temperature of the vessel, temperature of the material exiting the vessel and amount of colony forming units (CFU/g) detected on a sample of the material.

In one embodiment, as shown in Figure 4, the system 1' comprises heat transfer means, in the form of air fans 34', operative to extract heat from the material as it passes through the vessel 2'. The air fans 34' are provided in the frusto-conical section 26' to provide a drying zone.

In the embodiment of Figure 4, the ozone is provided via an injection plenum collar 36' located adjacent the upper end 4' of the vessel 2'.

As shown in Figure 3, the system 1, 1' is part of an apparatus 40 for oxidising a granular organic material. The apparatus 40 comprises a bag unloader 42 in communication with a buffer hopper 44 which in turn is in communication with the system 1, 1' as described above.

The bag unloader 42 and buffer hopper 44 are operative to provide the granular organic material to system 1.

In use, granular organic material is provided into vessel 2, 2' via inlet 8,8' at the upper end 4, 4' of the vessel 2, 2'. As the material falls through the vessel 2, 2' from the upper end 4, 4' towards the lower end 6, 6' of the vessel 2, 2', the system 1, 1' material is agitated by the agitating plates 32, 32' and the discharge agitator 28, 28' and exposed to a pressurised supply of ozone provided by an ozone injection means 14, 14'. The drive means rotates the baffles 12, and together with the agitation, improves efficiency of oxidation of the material on exposure to ozone.

As the material enters the frusto-conical section 26, 26' of the vessel 2, 2', air is forced into the vessel 2, 2' by air fans 34' and passes through the granular material. The number, combination and location of fans may vary depending on the requirements for the vessel and/or granular material. The airflow from the air fans 34' is typically within the range of 15 to 20 litres per second per tonne or material. In one embodiment, the air within the vessel 2, 2' is changed, by the air fans 34', every 25 to 50 seconds. The air flow provided by the air fans 34' has been found to be between 10 to 15 times greater than that achieved using conventional aeration.

The vessel, and in particular the frusto-conical section of the vessel, is configured to ensure a uniform air flow is achieved through the granular material.

The monitoring system monitors and senses the oxidation of the material such that the control system can vary one or more factors (as discussed above) to optimise oxidation of the material within the vessel 2, 2'. The heat transfer means is operated by the control system to ensure that heat is efficiently extracted from the material within the vessel 2, 2'. As the material reaches the lower end 6, 6' of the vessel 2, 2' the outlet 10 may be operated to either discharge the material, store the material or recirculate the material using the vertical re-circulator 16, 16' as required and in dependence on factors monitored by the monitoring system.

The monitoring system may for example determine that the amount of oxidised material within the material of the vessel 2, 2' is less than a predetermined minimum level and as such the control system may open the outlet 10, 10' and supply the material to the vertical re-circulator 16, 16' to ensure the material is re-supplied to the vessel 2, 2' for additional exposure to ozone.

Once the monitoring system has determined that the material within the vessel 2, 2' has reached sufficient oxidation levels, the outlet 10, 10' may be opened by the control system to discharge the material from the vessel 2, 2'. When the level sensor 30 determines that the volume of material within the vessel 2, 2' has reached or is in excess of a predetermined level, the outlet 10, 10' may be opened to discharge material.

The system 1, 1' of the present invention provides an efficient means for providing efficient oxidation of granular organic material.

Figures 9, 10 and 11 show an overall view of a silo and a depicts cross augurs 46 which promote recirculation of material as well as mixing. In combination with the angled butterfly wings 12. Each butterfly wing 12 angles the feast up past the cross augers 46. Cross augers 46 are hollow to inject ozone. Cross augurs 46 may counter rotate in order to promote mixing of material. Alternatively cross augers 46 may rotate in the same direction so as to ensure material (not shown) flows in a preferred direction through the processing vessel 2.

Upper and lower augers may operate at different speeds, however in order to avoid depletion or build-up of material it is important that throughput of material paste each auger, from above to below the respective auger 46A, 46 B is controlled so that the mass flow of material past each auger is substantially constant.

Butterfly flaps 12 have apertures 36 through which airflows to improve our circulation through the silo.

Apertures 36 have been found to improve mixing and overall efficiency of injection of ozone.

Apertures 36 may be arranged in a line or offset in a grid or array pattern. The example shown in figure 11 has five apertures in each butterfly wing. The example shown in figures 9 to 11 has four apertures in each butterfly wing. Apertures 36 in upper and lower butterfly wings 12 are offset one from another so as to be staggered, as can be seen in Figure 10, to promote mixing and sideways movement of material.

Butterfly wings are space to part one above one pair above another pair typically of a distance between 1 m and 4 m. This has been found to promote mixing and to improve airflow through the silo.

Material enters through the silo via entry port at upper end 4 of the processor vessel 2 and material is scattered via a dispersing scatterer 38. The scatterer 38 helps promote an even distribution of material so that it is forced sideways across as large an area of the butterfly wing 12 as possible thereby avoiding a build-up or agglomeration of material underneath entrance port. The scatterer 38 may include a rotating portion with serrations or ridges which helps to disperse the material over a larger area so that material is distributed more evenly, rather than fall over a smaller area.

Optionally the scatterer 38 has holes through which injection of a pressurised gas, which includes ozone, in order to expose the material to ozone, as well as promote mixing due to convective forces.

As a lower portion of the silo a gyrator 40 is provided which avoids clumping and coagulation and ensures a fluidic flow of treated product from the lower end 6 of the silo 2.

A recirculator 24 is provided for material which requires further treatment or post-processing, and this is introduced during the recycling phase at recirculator entrance port 48.

A diverter valve 58 selects a pathway for direction of treated material, and a sensing system determines whether the material requires further processing or whether it is suitable for use or storage or transport. If further treatment is required, the diverter diverts the material to the recirculator.

In one embodiment only the lower portion of the silo is deployed which may enable upper parts to be accessed for maintenance or repair.

Figure 14 shows a sectional view through a gas joint connector 80. Ozone gas is delivered via the connector to the upper cross auger 46A and lo lower cross auger 46B. Ozone gas is introduced under pressure to the rotating augers, at one end thereof, so that the ozone is distributed evenly along the length of the rotating member.

Ozone gas is delivered via hose and inject port 80. The gas joint connect 80 is mounted on a bearing mounting housing 82. A dual lip seal 92 ensures no ozone leaks from the port during operation. A transfer port 86 provides a pathway from the supply (not shown) to the internal silo. A double row of self-aligning bearings 88 ensure that, irrespective of any weight variation or variations in loading or vibration which are encountered by the silo, the there is no leakage from the delivery port.

Material is mixed and ozone injectors may also be provided in a lower portion of the silo between the lower butterfly baffles and exit port of the silo 2.

As the system operates under pressure closure caps 50 are provided so as to ensure the system is compliant for purposes of safety, especially from a point of view of explosions and ozone contamination.

Sensors are provided in different parts of the silo in order to monitor variables such as humidity and temperature and payload of material.

Blast panels, in the form of upper 52 and lower 54 burst hatches, are formed from a relatively weaker material such as polycarbonate serve as safety release dump valves in the event of an explosion, thereby avoiding the entire silo being damaged.

The invention has been described by way of example only and it will be appreciated tat variation to the aforementioned embodiments may be made without departing from the scope of invention as defined by the claims.

Parts List 1 system 2 processing vessel or silo 4 upper end 6 lower end 8 main feed inlet from bulk silo outlet 12 baffle or butterfly wing 14 pressurised supply of ozone 16 vertical recirculator 18 recirculator first end recirculator second end 22 opposed second end 24 recirculator 26 frusto-conical section 28 discharge agitator level sensor 32 agitating plates 34 air fan 36 apertures 38 dispersing scatterer gyrator 42 bag unloader 44 buffer hopper 46A upper cross auger 46B lower cross auger 48 recycling entrance port closure caps 52 upper burst hatch 54 lower burst hatch 56 rotating vertical lift 58 diverter valve sluice valve 62 bin agitator 64 ozone injector 66 double handed lower mixer 68 recycle feed motor inspection hatch or blast panel 72 flexible coupling 74 load cell a gas joint connector 82 bearing housing mounting 84 ozone injector port 86 transfer port 88 self-aligning bearing connector to cross screw 92 dual lip seal 94 retention circlip

Claims

Claims 1. A system for oxidising a granular organic material comprises: a system for oxidising a granular organic material comprising: a processing vessel having an upper end and an opposed lower end, in which the vessel comprises an inlet which is located at the upper end of the vessel, the inlet is configured to supply material from a delivery system to the vessel, and an outlet which is located at the lower end of the vessel; at least one baffle is provided within the vessel, the at least one baffle being dimensioned and arranged to disrupt the passage of the material falling from the inlet towards an outlet; and a pressurised supply of ozone gas is configured to pass ozone gas through at least one mixer aperture of at least one mixer to oxidise the material.
2. A system according to claim 1, wherein the vessel comprises a closable outlet providing a discharge point for removing material from the vessel, for storage or recirculation.
3. A system according to claim 2, comprising a vertical re-circulator configured to collect and transport material from the outlet of the vessel to the inlet of the vessel.
4. A system according to claim 3, wherein the vertical re-circulator includes a delivery system with a motor driven auger.
5. A system according to claim 3, wherein at least one mixer is defined in, or formed integrally with, the, or each, baffle.
6. A system according to claim 5, wherein at least one baffle has a plurality of apertures defined in a surface thereof through which, in use, granular organic material passes.
7. A system according to any preceding claim wherein at least one mixer comprises an auger or Archimedean screw which rotates about an axis and is operative so that material passes thereover.
8. A system according to any preceding claim wherein the vessel includes a substantially cylindrical silo.
9. A system according to claim 8, wherein a baffle is substantially planar and has a parabolic form and an edge which lies in a horizontal plane within the cylindrical silo.
10. A system according to claim 9, wherein a baffle is displaceable by way of at least one actuator which is operative to raise and lower a portion of the baffle, within the vessel, so that an angle enclosed between a plane, in which the baffle is defined, and the horizontal plane within the cylindrical silo, is variable.
11. A system according to any preceding claim, wherein two baffles are provided about an axis which is coincident with a diameter of the cylindrical silo.
12. A system according to claim 11, wherein an auger is disposed along the axis and is operative to introduce ozone gas into the bulk of material directed towards the auger by the baffles and falling towards the outlet.
13. A system according to any preceding claim, further comprising a drive means associated with the at least one baffle, the drive means configured to displace the baffle relative to the vessel.
14. A system according to claim 13, wherein the drive means includes a motor associated with the at least one baffle, the drive means being configured to rotate the at least one baffle with respect to the vessel.
15. A system according to claim 13 or 14, in which a plurality of baffles are provided in the vessel.
16. A system according to any preceding claim, in which the vessel comprises a frusto-conical section located at or adjacent the lower end of the vessel.
17. A system according to any preceding claim, further comprising a discharge agitator located at or adjacent the lower end of vessel and/or the outlet of the vessel.
18. A system according to any preceding claim, wherein the processing vessel has an upper end and an opposed lower end, in which the vessel comprises an outlet located at or adjacent the lower end of the vessel and a recirculator for recirculating material to the inlet.
19. A system according to claim 18 wherein a diverter is selectively operative, in dependence upon a control signal, to divert unprocessed material to the recirculator for recirculating material to the inlet or processed material to a storage hopper or material feeder.
20. A system according to any preceding claim, wherein a discharge agitator includes an actuator connected to a frusto-conical section of the vessel, and in which the agitator is displaced with respect to the vessel.22. A system according to claim 21, in which the discharge agitator includes a gyrator.23. A system according to any preceding claim, further comprising at least one level sensor configured to detect a level of material within the vessel.24. A system according to claim 23, further comprising a processing means configured to receive a signal from the at least one level sensor, and a controller operative to shut off supply of material to the inlet of the vessel, in response to the processing means detecting that a level of material within the vessel has reached a predetermined level.25. A system according to any preceding claim further comprising a cyclone which is provided for removing particles of material from the vessel having a particle size of smaller than 400 pm.26. A system according to any preceding claim, further comprising a dehumidifier which operative to extract moisture from within the vessel.27. A system according to any preceding claim, further comprising at least one agitating plate located in the vessel operative to promote mixing of the material.28. A system according to any preceding claim, further comprising at least one heat transfer means operative to extract heat from the material as it passes through the vessel.29. A system according to any preceding claim, further comprising a monitoring system operative to sense and monitor at least once material characteristic of the material and/or an at least once vessel characteristic of an internal volume of the vessel.30. A system according to claim 29, wherein the monitoring system is operative to sense and monitor an amount of colony forming units (CFU/g) on non-oxidised and oxidised material.31. A system according to claim 28 or 29, further comprising a control system operative to vary at least one of the following factors in dependence upon the material characteristic and/or the vessel characteristic, the factors from the group comprising: average particle size, mass flow of the material through the vessel, dwell time of the material in the vessel, concentration of ozone gas introduced into the vessel, moisture content of the material, humidity within the vessel, temperature of the vessel, temperature of the material exiting the vessel and amount of colony forming units (CFU/g) detected on a sample of the material.32. A system according to claim 31 further comprising a gas joint connector, for connection to a port, the connector is supported on a bearing mounting and has a dual lip seal configured to prevent leakage from the port.33. A method of oxidising a granular organic material comprising the steps of: introducing the material into a processing vessel; cascading the material over at least part of a surface of at least one baffle provided within the vessel; and passing ozone through apertures defined in the surface of the at least one baffle to oxidise the material as the material falls towards an outlet of the vessel.34. A system for oxidising a granular organic material, which is deployed between a silo/grain store in which a granular organic material is stored and an animal feeding system, comprises: a rotating auger supported in a hollow housing and a drive means which is operative to rotate the auger; a first end of the housing has a gas tight seal for connection to the silo/grain store and a second end of the housing has a gas tight seal for connection to the animal feeding system; an inlet port on the housing receives a supply of gas which includes ozone, and defines a gas tight pathway to a hollow interior section of the auger and holes formed in the auger allow passage of the gas to contact the granular organic material.