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US 4,989,363 AGranted
Bulk material treatment and apparatus
AssigneeDegesch GmbH
InventorManfred Doernemann
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AssigneeDegesch GmbH
InventorManfred Doernemann
Estimating the term…
Process and apparatus for protecting or preserving stored commodities, in particular bulk commodities such as agricultural produce, e.g. grain, against deterioration by pest action, comprising the introduction into and maintenance in the commodity in a substantially gas-tight enclosure of a pesticidal atmosphere comprising carbon dioxide. The carbon dioxide is admitted to the bottom of the storage space so slowly that it spreads out as evenly as possible in the bottom region, being mixed as little as possible with the air or like gas originally contained in the storage space and then displacing that air or gas progressively in an upward direction, to be vented to the atmosphere from the top of the space until the space is filled entirely with carbon dioxide in a predetermined concentration range. This range can be monitored and regulated automatically. Excess gas is vented through vent pipes, a slight back pressure being created by non-return flaps or throttles.
In a process for eradicating or controlling pests in bulk commodities, respectively for protecting or preserving stored commodities, against deterioration by pest action, comprising the introduction into and maintenance in the commodity in a substantially gas-tight enclosure of a pesticidal atmosphere comprising carbon dioxide, the improvement which comprises introducing and releasing a gas comprising carbon dioxide in a pesticidal concentration in excess of about 50% by volume to the bottom region of an enclosed space containing the commodity at a rate slow enough as to substantially avoid turbulence and thereby progressively filling the space with such gas from the bottom upwards, whilst displacing gas previously contained in the space upwardly towards the top of the space and from there discharging the displaced gas.
A pest control installation, comprising a storage space for a commodity, sealed in substantially gas-tight manner in relation to the atmosphere and means for supplying a gas comprising CO.sub.2 in a pesticidal concentration into the space, comprising duct and regulator means for the gas arranged to release the gas into the bottom region of the space in substantially non-turbulent manner and vent duct means adapted to release progressively displaced gas from the top region of the space, comprising means for creating a back pressure in the vent duct means, in the form of a non-return flap responsive to light excess pressure inside the space or a throttle, optionally adjustable, for creating the back pressure.
A pest control installation, comprising a storage space for a commodity, sealed in a substantially gas-tight manner in relation to the atmosphere and means for supplying a gas comprising CO.sub.2 in a pesticidal concentration into the space, comprising duct and regulator means for the gas arranged to release the gas into the bottom region of the space in a substantially non-turbulent manner and vent duct means adapted to release progressively displaced gas from the top region of the space, comprising sensor means for registering the carbon dioxide concentration at different localities of the space.
A pest control installation, comprising a storage space for a commodity, sealed in a substantially gas-tight manner in relation to the atmosphere and means for supplying a gas comprising CO.sub.2 in a pesticidal concentration into the space, comprising duct and regulator means for the gas arranged to release the gas into the bottom region of the space in a substantially non-turbulent manner and vent duct means adapted to release progressively displaced gas from the top region of the space, comprising a liquid carbon dioxide tank or bottle or battery of bottles, connected to a pipe leading to the duct leading to the bottom region of the space and valve means for controlling the feeding of carbon dioxide from the tanks, bottle or bottles.
A pest control installation, comprising a storage space for a commodity, sealed in a substantially gas-tight manner in relation to the atmosphere and means for supplying a gas comprising CO.sub.2 in a pesticidal concentration into the space, comprising duct and regulator means for the gas into the bottom region of the space in a substantially non-turbulent manner and vent duct means adapted to release progressively displaced gas from the top region of the space, comprising a tank for holding liquid carbon dioxide, a pipe for withdrawing the liquid carbon dioxide leading to an evaporator for vaporizing the carbon dioxide and pipe or pipes leading from the evaporator to the duct means leading to the bottom region of the space.
A pest control installation, comprising a storage space for a commodity, sealed in substantially gas-tight manner in relation to the atmosphere and means for supplying a gas comprising CO.sub.2 in a pesticidal concentration into the space, comprising duct and regulator means for the gas arranged to release the gas into the bottom region of the space in a substantially non-turbulent manner and vent duct means adapted to release progressively displaced gas from the top region of the space, comprising feed dust means with the gas outlet means, leading to the bottom region of the space adapted to receive solid carbon dioxide (dry ice) for gradual in situ vaporization and release of carbon dioxide gas formed thereby into the bottom region.
A pest control installation, comprising a storage space for a commodity, sealed in a substantially gas-tight manner in relation to the atmosphere and means for supplying a gas comprising CO.sub.2 in a pesticidal concentration into the space, comprising duct and regulator means for the gas arranged to release the gas into the bottom region of the space in a substantially non-turbulent manner and vent duct means adapted to release progressively displaced gas from the top region of the space, including a gas tight flexible foil for covering a commodity store to be disinfested and sealing the store from the atmosphere, comprising apertures through the foil adapted for the duct means for the gas to pass therethrough in a sealing relationship to the bottom ends of upwardly directed vent duct means.
Dependencies are inferred from the claim text.