DE69518412T2 - SYSTEM AND METHOD FOR FILLING AND SEALING CONTAINERS IN A CONTROLLED ENVIRONMENT - Google Patents

Abstract

An open-architecture system for filling and sealing containers (52) in controlled environments. The system provides easy access to containers being processed, and minimizes start-up times and waste. Containers are processed by gas distributors (which may comprise gassing rails (10)) provided in segments and individually movable between operating and service positions. Exhaust plenums (11) are described for improving function of the gas distributors when processing containers. Gas exchange systems including on-demand processors (5) and improved gassing elements are provided. An independent processor (5) is provided to receive, correct and environmentally process defective (e.g. underfilled or overfilled) containers (52).

Description

TECHNICAL AREA

The invention relates to devices and methods for packaging materials in selected alternative environments and in particular for packaging food products in containers in a substantially oxygen-free manner.

TECHNICAL BACKGROUND

In the food packaging industry, there are numerous methods for sequentially packing containers of food products in alternative environments, such as an inert atmosphere, to significantly reduce oxygen levels and thereby preserve freshness. Such operations are advantageous for packing various food products, including edible nuts, coffee, powdered milk, infant formula powder, among others. Existing systems have limitations that reduce the efficiency and speed of the packaging process. In addition, certain packaging system designs eliminate the choice of using various advanced filling and seaming equipment.

For example, methods are known to flush the interior of empty containers before filling them with contents to reduce residual oxygen. Methods are also known to reduce the oxygen content in food materials before packaging, as well as to transport the filled containers. However, devices for performing these functions have disadvantages that have prevented their widespread adoption. These include excessive gas consumption, inflexible construction which restricts operator access, lower operating speeds, a need for vacuum sources or cumbersome fixtures, and long delays during start-up and restart.

For example, U.S. Patent Nos. 3,871,157, 3,942,301 and 4,140,159 and German OS 3323710 disclose various devices for low oxygen packaging, including certain forms of gas distributors and cleaning bulk products. U.S. Patent No. 3,860,047 discloses a device for purging oxygen from a bulk product to be packaged, including gas supply pipes. U.S. Patent No. 4,094,121 discloses another device for packaging products in a substantially oxygen-free atmosphere, comprising a simple inlet for introducing inert gas which is to be forced upwards through a filling pipe and a filling funnel. These known systems all have the disadvantage of an inflexible structure, an undesirably high gas consumption, a possible disadvantageous stratification of the bulk product as a result of purge gas flows, and limited speed.

British Patent No. 551271 discloses a system and method according to the preambles of claims 1 and 47 respectively and provides means for evacuation of air from the headspace of containers and for sterilizing closures for the containers. Means are provided for directing steam into the containers moving through a tunnel in which jets of steam are directed into the headspaces of the containers to flush air out of them immediately before the containers reach a turret which effects a closure. Another system comprising jets of steam for removing air from the container prior to sealing the container is described in U.S. Patent No. 2,534,305.

It is therefore desirable to provide a system and method for packaging products in selected (e.g., inert) environments using generally open and accessible structures. It is further desirable to provide such a system which will enable very low residual oxygen levels in the packaged product while consuming less inert gas and avoiding stratification of the bulk product. Finally, it is highly desirable to provide such an integrated gassing system which is adaptable to multiple size containers and which is operable at high throughputs.

DISCLOSURE OF THE INVENTION

The invention relates to a system for flushing oxygen from open containers according to claim 1 and a method according to claim 47.

An integrated, open architecture container filling and sealing system is provided, which includes a pre-cleaning system (e.g., rail), a filling station including means to remove oxygen from a bulk material prior to packaging, a headspace cleaning rail, and a permanent sealing station. In a particular embodiment, the system essentially consists of only these main processing elements, with no need for other inert gas or vacuum processors, and is already capable of commercially packaging, for example, infant formula powder at high rates (e.g., 200 pounds (90.7 kg) per minute and higher) with residual oxygen levels of 1% or less.

In a preferred embodiment, empty containers are transported beneath a specially designed cleaning rail, then filled with a product which has itself been processed to remove substantially all oxygen, and finally the filled containers are transported beneath a gas space cleaning rail to a device for sealing the container. Preferably, both the container cleaning rail and and the gas space cleaning rail comprises one or more channels which are mounted above open containers on a conveyor in close proximity to the container openings. The channel is supplied with a desired alternative environment, such as inert gas. A longitudinally extending distributor for the controlled/regulated passage of gas from the interior of the channel towards the container openings is provided in the surface of the channel near the containers, which distributor is narrower than the container opening and which preferably has less than or equal to one half the width of the container opening, and in a particularly preferred embodiment has a quarter of the width of the container opening or less.

The rails preferably comprise a plurality of segments which are mounted in such a way as to allow individual segments to be easily removed from the associated conveyors and containers to allow access to a portion of the system and to containers being processed. In particular embodiments, segments may be hingedly or slidably mounted to allow rotational and/or translational movement from a first operating position to a second maintenance position.

Exhaust channels may be provided in conjunction with a gas distributor (such as a gassing rail) to receive the exhausted gas and oxygen. In preferred embodiments, the exhaust channels comprise an extended distributor for controlled/regulated (preferably laminar) gas introduction.

A filling station comprises means for removing substantially all oxygen from a product to be packaged prior to filling the container. Preferably, the filling station comprises a silo, a demand gas exchanger and a filling device. The silo (if used) may comprise at least one gassing area to provide a controlled/regulated and preferably to provide laminarized inert gas flow into the silo. The on-demand gas exchanger (if used) provides a more compact vessel (leading to greater installation flexibility) comprising an enclosed volume through which the product flows just prior to packaging, and includes gassing elements to provide a controlled inert gas flow through the product to displace oxygen in real time as the product flows through the filler for filling. In some embodiments, the silo and gas exchanger may be integral. The filler may be of any conventional type, but modified (if necessary) to prevent oxygen ingress as the processed product enters the processed containers and as the containers enter and exit the filler.

In preferred embodiments, the silo (or gas exchanger) is provided with a plurality of individual gassing elements arranged to create overlapping gassing areas. In a preferred embodiment, the elements are substantially coplanar and spaced throughout the internal volume of a vessel. In particularly preferred embodiments, more than one level of gassing elements is provided to create multiple oxygen exclusion zones as the product moves through the associated silo or gas exchanger. For example, two levels are preferred, each having three or four gassing elements offset relative to one another. The gassing elements preferably comprise an extensive distribution surface for injecting gas in a controlled (preferably laminar) manner over a substantial surface area, thereby preventing excessive velocity or turbulence. In preferred embodiments, a rigid support frame supports an extensive wire mesh distribution surface defining an internal channel which receives an inert gas supply. Preferably, the wire mesh distributor has an upper section (in the direction of the incoming product) which is tapered. A lower A generally parallel sided portion may also be present to provide additional surface area without adversely affecting particulate material flow through the vessel.

In certain embodiments, converging rails (such as headroom purge rails) may be provided near the main rail(s) to introduce containers into the container stream. In a system, a secondary oxygen purge station may be included for processing containers which may then be transported under a converging rail for introduction into a stream of containers without risk of oxygen contamination.

Further features and advantages of the invention will become more apparent from the following detailed description of the presently preferred embodiments, which is read in conjunction with the accompanying drawings. The detailed description and drawings are merely exemplary of the invention rather than limiting it, the scope of the invention being defined by the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic view of an integrated container filling and sealing system.

Fig. 2 is a bottom view of a gassing rail showing the outer surface of a preferred gas distribution manifold.

Fig. 3 is a sectional view taken along line 3-3 in Fig. 2 of a single container being cleaned by a pre-cleaning rail.

Fig. 4 is a sectional view taken along line 3-3 in Fig. 2 of a single container being cleaned by a headspace cleaning rail.

Fig. 5 is a bottom view of another gassing rail showing two embodiments of exhaust ducts.

Figure 6 is a side sectional view of a preferred rail and distribution structure.

Figure 7 is a partial sectional view of preferred conveyor and rail support means including pivot joints.

Figure 8 is a side view of a representative commercial embodiment of the present invention including a feed silo with a plurality of gassing elements, as well as an optional secondary processor and converging rails.

Fig. 9 is a top view of the embodiment shown in Fig. 8.

Fig. 10 is a top view of the fumigation silo shown in Figs. 8 to 9.

Figure 11 is a diagrammatic representation of an alternative commercial embodiment comprising a demand gas exchanger.

Fig. 12 is a side view of one embodiment of a demand gas exchanger.

Fig. 13 is a top view of the gas exchanger shown in Fig. 12.

Fig. 14 is a partially sectioned side view of a representative gassing element for use with a gassing silo or gas exchanger.

Fig. 15 is an end view of the gassing element taken along line 15-15 in Fig. 14.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring to Fig. 1, there is shown a schematic view of an integrated controlled environment filling and sealing system having gas purge rails 10 comprising a pre-purge rail 1 and a gas space purge rail 3, a filling station 2 between rails 1 and 3, and a sealing station 6 (such as a double seamer). The filling station 2 preferably includes a controlled environment processor 5.

The gas purification rails 10 comprise a longitudinal channel 11 with one or more inlets 12, for example, to receive inert gas from a source (not shown), and a distribution manifold 13 for distributing the gas into the open containers. The distribution manifold 13 is located on a surface of the rail 10 facing the containers. Where extended rails are desired (e.g., to increase the residence time of the containers beneath the rail to allow adequate time at a given line speed for sufficient oxygen displacement), the gas purification rail 10 may comprise a plurality of individual segments (e.g., 7, 8), each having its own channel 11 and gas inlet(s) 12. Preferably, the manifolds 13 of adjacent segments are located very close to each other (i.e., most preferably within 1/8 inch) to minimize any disruption of the longitudinally quiescent gas flow from the manifolds. For a preferred line speed of about 400 size 401 containers per minute, a total preclean rail length of about 12 feet and a dwell time below the rail of 4 to 6 seconds is desirable.

The vertical distance between the manifold 13 and the tops of the open topped containers is preferably small and should ideally not exceed about 0.953 cm (0.375 inches) for the illustrated embodiments. Preferably, for a pre-cleaning rail 1, this distance is between about 0.1588 and 0.635 cm (0.0625 and about 0.25 inches), not exceeding about 0.79 cm (0.31 inches), and optimally is about 0.32 cm (0.125 inches). For a headspace rail, the distance is preferably between about 0.047 and 0.483 cm (0.016 and about 0.19 inches), not exceeding about 0.953 cm (0.375 inches), and optimally is as small as possible without physical interference between the rail and the containers. For 401 size cans, a segment of the channel 11 may have a height of about 2.54 cm (1 inch), a length of about 122 cm (4 feet), and a width of about 12.7 cm (5.0 inches). A standard 401 container has a height of 13.813 cm (5.438 inches) and an outside diameter of 10.4 cm (4.1 inches). The inert gas has an inlet and outlet flow rate of about 0.057 to 0.425 cubic meters per minute (2 to about 15 standard cubic feet per minute (2-15 scfm)), preferably about 0.283 cubic meters per minute (10 scfm) per 122 cm (4 foot) segment at 100% flow when packing 401 x 502 size containers at a line speed of 300 containers per minute. For a gas space rail segment, the optimum rate is about 0.142 cubic meters per minute (5 scfm) per segment at 100% flow rate. The optimum inert gas flow rate will vary depending on line speed and container dimensions and can be determined by wind tunnel testing of containers of different sizes.

Preferably, the channel 11 is closed except for the inert gas inlet(s) 12 and the distribution manifold 13. The channel 11 may be rectangular as shown and may be constructed of stainless steel, aluminum, rigid plastic or any other rigid material. The channel 11 should preferably be at least as wide as, and more preferably slightly wider than, the Diameter of the open top of the containers. In a preferred embodiment, a 6.35 cm (2.5 inch) strip of 5-layer 40 micron stainless steel screen 23 is attached to a 6.35 cm (2.5 inch) strip of 2-layer 80 micron stainless steel screen 24 and partially forms the gas distributor provided. By providing opening areas in one or both grid layers (preferably non-overlapping), different flow resistance areas are provided.

In operation of a preferred embodiment, an open empty container 50 may be subjected to a controlled (preferably laminarized) flow of inert gas from the preclean rail 1 while being transported by the conveyor 59 which reduces the oxygen levels within the container from 20.9% to less than 2.0% residual oxygen. It has been found that oxygen residuals as low as a few hundred parts per million oxygen or less are possible with residence times of 4 to 6 seconds. Since the rails 1 as described herein do not require a vacuum, side plates or a sealed enclosure to process the empty containers 50, an open architecture is provided which allows easy access to the containers when necessary. Preferably, the preclean rails 1 include at least one longitudinally oriented gas distribution manifold section which is aligned substantially in the direction of travel of the containers being transported in association with the preclean rail. The distributor provides a controlled flow of, e.g., inert gas into the open containers, which flow is substantially continuous and uniform in the container movement direction. Preferably, the distributor provides at least two extended longitudinal regions of differing gas flow resistance. Preferably, the distributor has a width which is less than the width of the container opening, and most preferably is one-half or one-quarter or less of the container opening width. It should be understood that "longitudinal" direction is used herein to refer to the container movement direction, which may be linear or non-linear (e.g., curved), flat or non-flat, depending on the conveyor or transport system associated with the gas rail.

The filling station 2 comprises devices for portioning the bulk material 9 to be packaged and feeding it to the empty containers 50. In addition, device 5 is provided for removing oxygen from the bulk material 9 prior to filling the containers 50. This alternative environment processor 5 preferably has a plurality of gassing elements in the flow path of the bulk material 9 to provide a laminarized inert gas flow through the bulk material to substantially reduce oxygen levels in the product and prevent reintroduction of oxygen during filling of the pre-cleaned container.

The filled containers 52 then exit the filling station 2 beneath a headspace purge rail 3. The headspace purge rail 3 purges the headspace of the filled container 52 with a controlled/regulated inert gas flow pattern to eliminate any oxygen contamination that may occur when the containers exit the filling station, as well as to maintain the inert environment while the containers are transported. Like the pre-purge rail 1, the headspace rail 3 may preferably have an open architecture to allow access to filled containers 52, as well as manifolds of the type described above.

It has been discovered that high efficiency, very low oxygen residues at high speed can be achieved by a system consisting essentially only of the processing elements discussed. In other embodiments, the vessel 52 may enter another environmental processing station(s) (not shown), such as a vacuum chamber or an additional gassing station. A lid placement system 4 may be provided. The vessel 52 may be transported to a permanent sealing station 6. where a closure is secured. The sealed container 58 can then be removed.

This unique combination of vessel processing elements, including pre-cleaning and gas space cleaning via gassing rails and open architecture manifolds as described herein, provides for low residual oxygen in the filled vessel as well as very efficient (minimized) use of inert gas. The resulting open architecture allows easy access to the vessels 50, 52 and avoids complex tunnels, gas seals, vacuum processors and other interfering structures. Segmented rails and articulating segments, as discussed below, further enhance the openness of the resulting system and contribute to its excellent operation.

Referring to Figures 2-4, a preferred distribution manifold 13 for the pre-cleaning rail and headspace cleaning rail includes a longitudinally oriented central region 15 of lower flow resistance between and adjacent to two longitudinally oriented regions 16 and 17 of higher flow resistance. Each of the flow regions 15, 16 and 17 extends along the lower surface of the channel 11, is located above the open tops of the containers 50, 52, and is oriented in the direction of travel of the containers. In a preferred embodiment, the overall width of the distribution manifold 13 is less than the diameter of the openings of the containers, and most preferably is less than one quarter of the width of the container opening.

For example, the manifold 13 may have an overall width of about 19 to 25.4 mm (0.75 to 1.0 inches) for containers with opening diameters of about 10.2 to 15.3 cm (4 to 6 inches). The central region 15 with lower flow resistance may have a width of about 0.64 cm (0.25 inches) and the surrounding regions 16 and 17 with higher flow resistance may each have a width of about 0.64 to 1.28 cm (0.25 to 0.5 inches). Smaller vessels may use smaller optimum manifold widths. For vessels with opening diameters of approximately 2 to 3 inches (5.08 to 7.62 cm), the manifold may have an overall width of 0.5 inches (1.27 cm), with correspondingly smaller widths for the higher and lower flow resistance areas.

The distribution manifold 13 is preferably arranged longitudinally in the lower center surface of the channel 11 and above the centers of the moving containers 50, 52. In the pre-cleaning rails 1, the inert gas passing through the lower flow resistance center region 15 has a relatively high velocity sufficient to carry the gas to the bottom of each container 50. In the headspace cleaning rails 3, the velocity of the inert gas passing through the center region 15 is sufficient to carry it to the upper surface of the packaged product in the filled containers 52 and overcome any air infiltration during container transport. The arrows in Figures 3 and 4 show the preferred direction of travel of a preferably laminarized inert gas flow. Inert gas passing through adjacent regions 16 and 17 with higher flow resistance may be partially carried into the vessels 50, 52 by a "venturi" effect from the higher velocity gas. Otherwise, the gas passing through regions 16 and 17 has a lower velocity. Since regions 15, 16 and 17 are oriented parallel to the direction of travel of the vessels, the gas flow patterns (including outflow) are continuous and essentially at a steady state for the entire time each vessel remains below the surface of channel 11. Therefore, there is no opportunity for oxygen to enter the vessels from outside. The oxygen content within the vessels continually decreases as each vessel moves below manifold 13 until the oxygen content is reduced to target levels or below, thereby completing cleaning.

The high and low flow resistance regions 15, 16 and 17 can be created by using adjacent welded screens with different opening sizes, selectively layered screens, porous plastic (e.g. porous high density high molecular weight polyethylene), porous plates or any selectively porous material that acts like a diffuser.

In preferred embodiments of both the preclean rail 1 and the headspace clean rail 3, the manifold 13 may include a series of 0.64 cm (0.25 inch) wide and 7.62 cm (3 inch) long slots 25 formed in the center of a 5-layer 40 micron screen parallel to the vessel travel direction (Fig. 2). The slots may be spaced approximately 1.9 cm (0.75 inch) apart and provide an area of lower resistance to allow for higher velocity flow. The 1.9 cm (0.75 inch) spacing of the slots provides greater structural integrity to the rail, however a long continuous slot may be preferable. The screened areas on either side of the slots provide the higher resistance areas 16, 17 which allow a lower velocity flow parallel to the low resistance area 15 and to the direction of the vessel run 7. In an alternative embodiment where there is a reduced need for inert gas, the slots (Fig. 5) can be replaced by smaller holes 26.

Fig. 4 also shows two embodiments of exhaust channels 37a, b. Such exhaust channels can be provided in conjunction with a gas distributor, such as (but not limited to) a gassing rail 10, to receive all or part of the exiting gas as well as the displaced oxygen-containing atmosphere. This can be advantageous, for example, where it is desired to minimize accumulation of spent inert gas, or where more precise control of the gas flow pattern in the channels connected to the container openings adjacent areas is desirable. A source of exhaust (e.g., high or low vacuum) may be provided at outlets 38. The channel 37 is then provided with one or more ports 39 through which the spent gases are drawn. Ports 39 may in some embodiments comprise an elongated manifold and may preferably extend substantially coextensively with the distribution manifold 13. In preferred embodiments, the ports may comprise a longitudinally extended opening and may be covered by a fine wire mesh (see Fig. 5). In this manner, the gas flow patterns in the vicinity of the port(s) are calmed and preferably laminarized to further reduce stall flows in the region of the vessel openings.

In the embodiment shown to the left of channel 11 in Figure 4, an exhaust channel 37a is substantially adjacent to gas channel 11 and may share common elements with channel 11. Gas ports 39a, which may include individual openings, slots, a grid-covered manifold, or other configurations, are coplanar with distribution manifold 13 and the lower surface of the rail, respectively. In the alternative embodiment shown to the right of channel 11, exhaust ports 39b are provided at a level below the rail, at or below the open surface of the vessel. These and other physical embodiments are possible without departing from the scope of the present invention. Furthermore, although exhaust channels have been described in connection with certain preferred forms of gas distributors (such as gassing rails), they may also be advantageous in connection with other known types of gas distributors or purge systems.

Fig. 6 illustrates a particularly preferred configuration for the gas rail 10 and the manifold 13. In particular, the rail comprises two main elements, an upper assembly 91 and a lower assembly 92. Assembly 91 may comprise an upper plate 20 having a generally U-shaped cross-section. All relatively permanent connections to the gas rail are preferably made on the upper assembly 91, which for this reason preferably comprises a gas inlet 12 and means for mechanically supporting the assembled gas rail.

The lower assembly 92 is designed to be easily removable for cleaning, maintenance or replacement of the manifold. In the illustrated embodiment, side members 21, 22 form a box which, when connected to the upper assembly 91, defines a closed channel 11. Quick-fit clamps 30 are provided to selectively secure the lower assembly 92 to the upper assembly 91. In the illustrated embodiment, buttons or slotted members 30 are provided which are attached to helical brackets 32 such that the brackets 32, when rotated, engage and secure a portion of the side members 21, 22 against a cooperating portion of the upper member 20. Seals 33 may be provided to ensure a gas-tight seal. It will be understood that alternative means for connecting the assemblies 91, 92 may instead be used without departing from the scope of the present invention, as may alternative constructions for the various elements comprising the channel.

The lower assembly 92 can therefore be quickly separated from the more permanently attached upper assembly 91. In this way, the lower elements can be quickly exchanged for others, such as when it is necessary to provide a clean distributor, this can be particularly important where different products are packaged at different times and contamination must be carefully prevented.

Also shown in Figure 6 is preferred means for attaching the manifold screens or elements to the lower assembly 92 to allow improved access for maintenance and cleaning. In particular, threaded bosses 34 are provided on the sides 21, 22. Cooperating openings are provided in the manifold elements which are then slid over the bosses 34. Smoothing rods or clips 35 may be provided to ensure a longitudinal seal on the manifold elements which may be secured by, for example, wing nuts 36. This provides a quick-assembly structure 72. It will be understood that other attachment structures 72 may alternatively be used, such as spring or friction mounts. Alternatively, the manifold elements may be permanently attached to the supporting channel structures.

As shown in Figure 7, a baffle plate 71 may be located below the gas inlet 12 to disperse the incoming gas in the channel 11 and minimize noise. Although preferably solid, other embodiments may use permeable baffles, such as a grid or a perforated stainless steel plate.

Fig. 7 further illustrates a preferred open architecture for the gassing rail systems. A conveyor 59 is provided to transport the containers (50, 52). Conveyor 59 may be any suitable type including linear, curvilinear, circular, screw feeder, roller or other systems. In a preferred embodiment, support channel 54 supports interconnected conveyor elements 55 which are driven by drive means (not shown).

Proper orientation of the containers relative to the conveyor 59 may be assisted by optional guides 76. Preferably, the guides 76 are adjustable as shown (e.g. supported by adjustment rods 77 and secured by quick-mount knobs 78). This allows containers to be different sizes can be accommodated quickly and promotes the desired open architecture by allowing access to the conveyor stream when required.

The gas purge rail segments 10 are preferably, importantly, mounted in a manner that allows easy adjustment to accommodate differently sized containers and to allow easy access to containers with minimal disruption to a packaging operation. For example, support members 73, 74 may be secured by quick-adjustment clamps 75. In this manner, the rail 10 can be adjusted laterally at a location centered with respect to the containers and can be adjusted in height relative to the conveyor members 55 to ensure proper location and clearance above the open container tops.

In a particularly preferred embodiment, the upper (horizontal) support member 74 is movable relative to the lower (vertical) support member 73, which in turn is connected to the conveyor 59 (e.g., the support structures). The two members are connected by a selectively displaceable connector, such as a pivot or swivel 89, or by a translatory slider. Accordingly, the gas rail 10 and associated support structures can be quickly moved from a first operating position near the containers to a second servicing position away from the container stream. As shown, the swivels 89 can have a generally horizontal axis of rotation, being offset from the rail such that the rail structure can be moved away from the containers without interference. Alternatively, the rail segments 10 can be hinged to pivot about a vertical or angular axis or can be attached to sliders for translatory movement. Composite swivels or hinged structures can also be used. In particularly preferred embodiments, the pivot joints 89 or other support structures which allow movement of the Rail 10 allows for movement generally away from the remaining elements of a packaging apparatus so that the rail segments can be moved from an operating position to a maintenance position without disturbing other elements of the packaging apparatus.

Use of the present structure provides a highly accessible and open architecture which minimizes downtime when a container needs to be introduced or removed from the system. By merely pivoting (and/or sliding) the relevant segment of the affected rail away from the conveyor, an operator can immediately gain access to specific containers being processed. However, the majority of the containers may remain unaffected since in preferred embodiments only a portion of the rail needs to be disturbed. Furthermore, when the gassing rail segment is returned to its operating position, the system will return to normal operating conditions since the volume of space contaminated by ambient oxygen is kept relatively small compared to the large volume of, for example, known gas-filled conveyor tunnels. Although these advantageous mounting structures have been described in connection with preferred forms of gas distributors (e.g., gassing rails), they may also be advantageous in combination with other known forms of gas distributors.

A representative commercial system utilizing the present invention is diagrammatically illustrated in Figures 8 to 10. A series of empty containers 50 are fed by conveyor 59 to a filling station 2 beneath a segmented and articulated pre-cleaning rail 1. Nitrogen gas is supplied to the channel of each rail segment through hoses (not shown) attached to the gas inlets. The gas supply to each rail segment may preferably be individually controlled so that interruptions of gas to an individual segment (ie when the segment has to be removed for maintenance) does not necessarily require the interruption of gas flow to the remaining segments. This ensures that only a minimum number of containers are contaminated. For this purpose, a position detector (e.g., a proximity detector 120, Fig. 7) can provide a signal indicating whether the rail segment is in its operating position.

The conveyor 59 feeds empty containers 50 to a filling station 2 which may comprise any of a number of known product filling devices. For example, checkweighers, augers, rotary valves, in-line indexing, net weights and other known devices may be used to portion product and fill containers. The system shown comprises a circular turret filling head 29 for feeding product to the containers and a filling bowl 28 for portioning and dispensing the bulk feed material to the turret filling head.

The filling bowl 28 and other elements of the filling apparatus are preferably sealed and supplied with an alternative environment (e.g. inert gas). For example, gas inlets 46 may be provided. By properly enclosing the necessary sections of the filling apparatus, oxygen contamination can be prevented as the processed product enters the containers 50 from the silo 40. An oxygen sensor 47 may also be provided in the filling bowl or at other locations in the filling apparatus.

The bulk material 9 is fed to the filling bowl 28 through a storage or flow buffer silo 40. The silo is provided with a plurality of gassing element inlets 42, 43. In preferred embodiments, an oxygen sensor 44 is provided at the outlet of the silo 40 to allow monitoring of the residual oxygen in the material fed to the filling device. Preferably, a vent 45 is provided to to vent excess purge gas as well as the displaced oxygen atmosphere. The vent 45 may be mounted, for example, on a roof ventilation outlet, as may the exhaust ducts 37, if used. The vent may include a pressure relief valve to maintain a slight positive pressure (e.g., 2.54 to 5.08 cm (1 to 2 inches) of water) inside the filling apparatus. This helps to eliminate oxygen infiltration, particularly during idle periods when the bulk material outlets (through which the containers are filled) are potentially exposed.

In a preferred embodiment, the pressure relief valve may comprise a valve chamber having an internal bore with a lower shoulder, and a "floating" valve element supported on the shoulder. When excess pressure builds up in the filling cup, this pressure acting against the face area of the valve element will lift it from the shoulder, providing a path to vent gases. By adjusting the weight of the valve element (or by providing other biasing means), the set point of the pressure relief valve can be adjusted for a particular filling device and bulk material. The pressure relief valve may be formed with quick connect clamp ferrules at one or both ends to enable it to be quickly attached to a cooperating ferrule on the filling device. A ferrule at the outlet of the valve allows for quick connection to, for example, an exhaust system. A filter element is preferably included to prevent particulate matter from entering the exhaust system or fouling the valve.

In typical rotary fillers, star wheels 48 or other similar systems are used to pick up containers from a linear conveyor and place them in the rotary filler and similarly remove filled containers from the rotary and feed them to an output linear conveyor. Where such structures are part of the particular filling station 2 used, corresponding gas purge rails may be provided to correspond to the curvilinear container path. For example, the pre-purge rail segment 48 includes a curved portion dimensioned to accommodate the path of container travel as empty containers are loaded into the illustrated filling apparatus. Similarly, the gas space rail segment 49 includes a curved portion which corresponds to the path of travel of filled containers as they exit the filling apparatus. It will be understood that other shapes and dimensions of gas purge rails may be provided to accommodate the particular can paths of numerous filling apparatus.

Headspace cleaning rails 3 are shown in connection with conveyor 59 to transport the filled containers 52 to a sealing device 6. This may, in preferred embodiments, comprise a rotary double seam seaming machine for use with cans and lids having pre-formed seams. It should be understood that other forms of sealing devices may be used in a similar manner in connection with cans and other forms of containers. Furthermore, the headspace cleaning rails should take up substantially the entire travel of the can to and into the sealing device. If necessary, gassing elements may also be provided in the sealing device to prevent oxygen contamination during the sealing process.

In the embodiment of Fig. 8, the silo 40 and the gassing elements 42, 43 comprise the controlled environment processor 5 (see Fig. 1) to displace oxygen from the bulk material 9. Two levels of gassing elements (42, 43) are shown. As shown in Fig. 10, in each level there are preferably four elements approximately 90° relative to each other and the two levels are offset 45° relative to each other. The gassing elements are dimensioned and arranged such that the Areas of gas exchange produced by each element overlap with those of adjacent elements. It has been found that this results in an oxygen exclusion zone which is effectively continuous across the vessel cross-section. Oxygen-containing gases entrained in the bulk material passing through the zone are therefore effectively displaced by inert gas and the material leaves the zone with a substantially lower residual oxygen content. By providing elements at more than one level relative to the product flow, two or more exclusion zones can be created and the bulk material will pass in the vicinity of at least one and in most cases two gassing elements. The amount of oxygen removal can be influenced by, for example, the number of gassing elements, their location, the flow rate and type of material through the processor, and the gas flow rate through the elements. For some products a single level of gassing elements is sufficient, although two are preferred.

During start-up, a flow of gas through the manifolds of the pre-cleaning rails 1 will rapidly drive off oxygen that may be present in the empty containers 50. Nitrogen is a preferred inert environment, although others may be used. Once the various elements are adequately cleaned, the containers may be processed as previously described. The unique combination of advantageous elements provided by the present invention provides for a very rapid start-up with minimal loss.

Fig. 8 and 9 further diagrammatically illustrate certain optimal stations which can advantageously be incorporated into an overall system. For example, checkweighers can be included, either after the filling device 2, before the filling device, or both. By monitoring the weight of the filled containers 52, any over- or under-filled container can be identified. Preferably, an ejector 110 can then remove the incorrectly filled container from the container 59, for example by ejecting the can laterally away from the conveyor. Likewise, incompletely processed containers (e.g., those containing potentially undesirable oxygen levels) may be ejected. Such functions are facilitated by the open architecture of the present invention described above.

Previously, containers rejected in this manner were typically discarded, resulting in product and container waste. To overcome this disadvantage, preferred embodiments of the present invention may include a secondary environmental processor 112. Incompletely processed containers ejected from conveyor 59 may be transported to a work and buffer table 113. An operator may then manually adjust the fill of the containers to a proper weight (if necessary) and then process the container through the secondary environmental processor 112 to expel oxygen from the container and its contents. For example, an apparatus such as described in U.S. Patent No. 5,228,269, owned by the present applicants, may be used. Once processed, the container may then be transported under a secondary gas space rail 114 which merges into the main gas space rail 3 (e.g., is parallel to and adjacent to rail 3 for a distance). By using a gas space purge rail in this way, any oxygen entering the vessel as it is removed from the secondary processing station is quickly expelled and contaminating oxygen is excluded from the vessel while being reintroduced into the main vessel stream prior to the sealing station 6. Again, this advantageous function is optimized by the open architecture design described above. Although the use of a secondary environmental processor has been described in the context of preferred embodiments including certain forms of gassing rails, it should be understood that these aspects of the present invention are not limited to the present invention. Invention are equally useful in combination with other environmental processing and/or transport systems.

11-13 illustrate alternative and generally preferred embodiments for the controlled environment processor 5. In particular, an on-demand gas exchanger 60 is illustrated including a plurality of gassing element inlets 61, 62. Although the operation of the gas exchanger 60 is somewhat similar to that of the previously discussed silo 40, the exchanger 60 is optimized for rapid, on-demand processing of a relatively fast moving product. In a preferred embodiment, the gas exchanger 60 includes a processing area 63 and preferably two levels of three gassing elements each, staggered as shown. The central processing area 63 provides sufficient internal volume to accommodate gassing elements of sufficient surface area to provide the necessary gas volumes while maintaining a controlled and preferably laminarized flow. The residence time of the product passing through the gassing area can also be optimized. However, the volume of area 63 is preferably small enough to allow rapid, intensive, real-time processing of material as it flows through for packaging.

An outlet section 66 is shown which may preferably have a conical profile to facilitate particulate material flow. In some embodiments, the gassing elements may be located entirely within a main body of the vessel (e.g., Fig. 11), while in other more compact embodiments, some of the elements may also be located in the outlet section 66 (e.g., Fig. 12). A corresponding conical inlet section 68 attached to the inlet 66 may also be provided, as well as a vent 45 for displaced gases.

An oxygen sensor 64 is preferably provided in the outlet section 67 to monitor the residual oxygen of the material as it is fed to the filling station 2 and one may further be provided at the inlet. Optionally, an isolation or control valve 69 may be provided between the gas exchanger 60 (or silo 40 of Figure 8) or other connection means may be used to selectively isolate the filling device from the processor 5 with the controlled environment.

In use, each gassing element 80 will establish a surrounding gassing zone, with the inert gas introduced through the manifold displacing the oxygen-containing ambient atmosphere from the incoming bulk material. By locating the gassing elements with respect to a relatively compact processing zone 63 within the interior of the gas exchanger 60, the gassing zones of adjacent elements can be designed to overlap such that an effectively continuous gas replacement (oxygen exclusion) zone is established across the entire cross-section of the processing zone 63 perpendicular to the direction of bulk material flow. Because of the relatively compact dimensions of the preferred gas exchanger, particulate material passing through the processing zone 63 will pass very closely past at least one, and preferably more than one, gassing element.

It has been discovered that by creating an oxygen exclusion zone in this way, a surprisingly efficient gas exchange ratio can be achieved. For example, it has been found that nearly 98% efficient inert gas utilization can be achieved, whereby each volume of incoming inert gas displaces a substantially equal volume of entrained oxygen-containing atmosphere. It was previously thought that significant countercurrents of excess inert gas flowing back through the incoming material were necessary or advantageous for efficient gas displacement. Surprisingly, applicants have discovered that such countercurrent flow is not necessary and is actually not desirable, especially for products that are sensitive to flavor separation.

To facilitate desirable operation, the vent 45 may preferably include an extended removable filter element to prevent particulate matter from entering the exhaust system. For example, a collar with quick connect ferrules may be provided at each end including means inside thereof for receiving a filter element. The filter element may, for example, comprise a 6.35 cm (2.5 inch) diameter, about 22.86 cm (9 inch) long cylinder of 5-ply 40 micron screen. The preferred filter element may then be attached to a vent outlet with a cooperating ferrule or removed for maintenance or cleaning. An exhaust system may be attached to the ferrule at the outlet end.

In some configurations, it may also be desirable to provide a check valve or pressure relief valve in conjunction with the vent. For example, a valve having ferrules on its inlet and outlets, as previously described in conjunction with a filler, may be provided and mounted between the filter collar and an exhaust system. By providing each cooperating element (e.g., vent outlet, filter collar, pressure valve, and exhaust connection) with cooperating ferrules, a system is provided that can accommodate multiple configurations and rapid assembly/disassembly. In certain embodiments, the filter and valve may be provided in a unified element.

When material enters the demand gas exchanger 60 and encounters the oxygen exclusion zone created by the gassing elements 80, entrained oxygen-containing gases will be displaced. This volume of displaced gas can lead to an increased pressure in the inlet region 68, which in turn can create a counterflow of displaced gases. A such counterflow may interrupt the desired flow of particulate material (e.g., cause bridging or product stratification). To prevent such interruptions, a large inlet channel may be used which is sized to accommodate the increased pressure and counterflow. Preferably, however, the pressure relief valve and vent 45 are provided in an inlet region above the gas exclusion zone. The displaced gases can then exit without developing harmful increased pressure or gas counterflow, allowing the use of more compact transport channels.

Bulk material may be supplied to the inlet 66 of the gas exchanger 60 by any suitable means. In preferred embodiments, the product is supplied from the silo 40, which also contains gassing elements. In this manner, the bulk material can be preprocessed in the silo and maintained at a relatively low oxygen level, with the final oxygen reduction being completed in the gas exchanger 60 as needed. It should be understood, however, that the use of gassed silos is optional. In fact, in many preferred systems, the on-demand gas exchanger 60 provides all or substantially all of the inert gas processing required for the incoming product, reducing or eliminating the need for slower preprocessing in silos. Using the on-demand gas exchanger in this way has the advantage of minimizing the residence time of the bulk material within the inert purge atmosphere. For certain products (e.g. coffee), this rinsing is supposed to remove desirable volatile aromas or flavors that are detrimental to the product. By minimizing such contact while providing highly effective oxygen displacement, adverse effects are minimized or avoided.

Figures 14-15 illustrate a presently preferred embodiment of a gassing element 80 which may be used in conjunction with silos 40 or a gas exchanger 60. The gassing elements preferably have an extended length and a porous but rigid construction. A preferred cross-section includes a tapered upper section 81 to displace flowing material around the sides of the gassing element. This minimizes forces acting on the gassing element and has been found to prevent bridging or interruption in the flow of particulate material. To provide a larger surface area for preferential smooth passage of an appropriate volume of inert gas through the gassing element, generally parallel side sections 82 may also be provided. These provide support for the tapered top section 81 and contribute significant additional surface area for gas passage, but do not create significant additional friction with respect to the particulate material passing therethrough. Both the top section 81 and the sides 82 are preferably formed from a stainless steel grid selected to provide controlled and preferably laminarized gas flow into the bulk material, such as a 5-layer 20 micron laminated stainless steel grid. This provides adequate resistance to distribute the inert gas over the entire surface area of the element distributor and provides uniform, constant laminar flow while also providing appropriate mechanical strength to the element. It has been discovered that substantially laminar flow is desirable to avoid stratification or separation of particles of the product having different sizes. It has been further discovered that use of the present invention minimizes or eliminates collapse of fragile particles during deoxygenation, such as instantized coffee or an agglomerated product.

To provide mechanical support to the grid, a base bearing 83 and an end cap 84 may be provided. Preferably formed of stainless steel, the base bearing and end cap may include recesses for receiving a removable grid member, and also fabrics, if desired, which increase internal strength. By providing a removable grid, the manifold may be removed for replacement or cleaning, and all internal portions of the channel are easily accessible for cleaning.

The gassing elements preferably extend sufficiently inwardly from the inner wall of a vessel so that the ends of the plurality of gassing elements are close to one another, close enough to provide a uniform oxygen-excluding inert gas barrier, but without impeding particulate matter flow between the elements. The gassing element 80 may preferably be disposed at a downwardly sloping angle of about 5° from the horizontal. To permit removal of the elements for cleaning or replacement, they may preferably be medically welded or otherwise secured to the vessel through inlets 85. A seal 86 is disposed between mating surfaces of the gassing element 80 and the inlet 85. Gassing elements 80 are preferably secured to the inlet 85 by a removable clip 87, such as a clip 88. B. a quick-release pipe clamp made of stainless steel (health-safe 3A rating).

Inert gas is supplied to the gassing element 80 through the inlet 88. In conjunction with a silo, a flow rate in the range of about 0.028 to 0.566 cubic meters per minute (1 to 20 scfm) per element, and preferably 0.085 to 0.113 cubic meters per minute (3 to 4 scfm) has been found to be advantageous for elements which are about 38.1 cm (15 inches) long and 1.9 cm (3/4 inch) wide at the base. As previously noted, the flow rate depends on, for example, the type of material being processed, the rate and type of material passing through the silo, the physical dimensions of the silo and the oxygen content of the input material. For example, bulk products that include gases (such as in-shell peanuts) may require a higher residence time and/or a higher inert gas flow rate. In contrast, relatively large, solid products (such as shelled and de-shelled peanuts) may require less residence time and/or gas. By monitoring the residual oxygen content at the silo output, an operator can easily determine an approximate flow rate for a particular product and a setting.

The gassing elements in gas exchanger 60 are preferably identical to those previously described, although the overall dimensions differ to accommodate the smaller size of gassing area 63. Flow rates per element of about 0.028 to 0.142 cubic meters per minute (1 to 5 scfm) per element are desirable and particularly 0.042 to 0.057 cubic meters per minute (1.5 to 2 scfm) have been found to be advantageous. In a particularly preferred embodiment, six elements in two staggered levels (as shown), each about 17.78 cm (7 inches) long and 1.9 cm (3/4 inch) wide at the base, are provided with 0.011 to 0.05 cubic meters per minute (0.4 to 1.75 scfm) for processing infant formula powder at 90.7 kg (200 pounds) per minute and higher. It should be understood that other shapes may be employed in a similar manner, such as elliptical or other cross-sections.

While the embodiments of the invention disclosed herein are presently considered to be preferred, various changes and modifications may be made without departing from the scope of the invention. The scope of the invention is set forth in the appended claims.

Claims (55)

1. A system for purging oxygen from open containers (50, 52) moving along a conveyor (59), comprising: a gas distribution chamber (11) extending longitudinally along the conveyor, the gas distribution chamber including an inlet (12) for receiving an alternative ambient gas from a source; the gas distribution chamber comprising a distribution manifold (13), the distribution manifold comprising at least one longitudinal flow resistance region which allows a flow of the alternative ambient gas to pass through the flow resistance region and enter the container, characterized in that the flow resistance region has a flow resistance which varies across its width to provide a different flow rate of the alternative ambient gas into the container (50, 52), whereby the flow of the alternative ambient gas creates a gas inflow and outflow pattern which is substantially continuous and substantially at a steady state for the entire time the container is being purged. 2. A system according to claim 1, wherein in use the width of the distribution manifold (13) is about one-half the width of the container opening or less. 3. A system according to claim 1, wherein in use the width of the distribution manifold (13) is about one quarter of the width of the container opening or less. 4. System according to claim 1, wherein the distributor (13) and the flow resistance region along the distribution chamber (11) are substantially continuous. 5. System according to claim 1, further comprising a return gas chamber (37a, b) which is arranged adjacent to the longitudinal sides of the distribution chamber (11) and which receives the gas leaving the container (50, 52). 6. The system of claim 1, wherein the at least one longitudinally oriented flow resistance region comprises at least one longitudinally oriented region of higher flow resistance and at least one longitudinally oriented region of lower flow resistance. 7. The system of claim 1, further comprising at least one exhaust duct (37a, b) proximate the gas distribution chamber (11) for receiving and conveying exhaust gases including at least a portion of the alternative ambient gas, the exhaust duct comprising ports (39a, b) for admitting the exhaust gases and an outlet (38) for attaching the exhaust duct to the exhaust system. 8. The system of claim 7, wherein the ports (39a, b) comprise a longitudinally extending exhaust manifold which is generally parallel to the distribution manifold (13) and coextensive therewith. 9. System according to claim 8, wherein the exhaust manifold (37a, b) enables a substantially laminarized flow of gases in the region between the exhaust manifold and the gas supply region. 10. System according to claim 9, wherein the exhaust manifold (37a, b) comprises a fine wire mesh. 11. The system of claim 7, wherein the ports (39a, b) are substantially coplanar with a surface of the manifold facing the containers, in a direction toward the containers. 12. The system of claim 1, wherein the system includes bearings (73, 74) for suspending the gas distribution chamber (11), characterized in that: the gas distribution chamber has at least one operating position near the container openings and a service position displaced away from the containers (50, 52), the bearings comprising adjustable bearings having a first portion (73) connected to a base and a second portion (74) connected to the gas distribution chamber and movable relative to the conveyor (59) between at least two positions corresponding to the operating and service positions; the first and second positions being mechanically connected by a selectively displaceable connecting element (89). 13. System according to claim 12, wherein the selectively displaceable connecting element comprises a rotary joint (89), and wherein the gas distribution chamber (11) is rotatably displaceable between the operating and the maintenance position about an axis defined by the rotary joint. 14. The system of claim 12, wherein the selectively displaceable connecting element (89) comprises a slide, and wherein the gas dis distribution chamber (11) can be translated between the operating and the maintenance position. 15. The system of claim 12, wherein at least the second portion (74) of the adjustable bearing is further adjustable to provide a selectable distance between the conveyor surface and the opposing surface of the gas distribution chamber (11) when the gas distribution chamber is in the operative position. 16. The system of claim 12, wherein the distribution chamber (11) comprises a plurality of individual distributor segments, at least some of the distributor segments comprising individual adjustable bearings such that one segment can be moved to its respective service position while at least one other segment remains in its respective operating position. 17. System according to claim 1, wherein the system comprises a filling station (2) for filling the containers (50) with at least one bulk material and a sealing station (6) for permanently sealing the containers after they have been filled, characterized by: a pre-cleaning rail (1) comprising at least one longitudinally oriented gas distribution chamber (11) which is aligned substantially in the direction of movement of the open containers (50) being transported along the conveyor (59), wherein the distribution manifold (13) provides a controlled flow of a selected alternative ambient gas into the open containers, the flow being substantially continuous and uniform in the longitudinal direction; a filling station (2) comprising a processor (5) with a controlled environment to remove oxygen from the bulk material (9) before the open containers (50) are filled with the material; and a gas space cleaning rail (3) and a conveyor (59) for transporting the filled containers (52) from the filling station to the sealing station, the gas space cleaning rail comprising at least one longitudinally oriented gas distribution chamber which is substantially aligned with the direction of movement of the filled containers, the distribution manifold providing a controlled flow of a selected alternative environment into the open containers, the flow being substantially continuous and uniform in the longitudinal direction. 18. System according to claim 17, wherein the processor (5) with the controlled/regulated environment comprises a gas exchanger for receiving the bulk material (9) while it is transported to the filling station (2) for filling, the gas exchanger comprising a gassing area including gassing elements (42, 43). 19. The system of claim 18, wherein the processor (5) with the controlled/regulated environment comprises at least one buffer silo (40) with a plurality of gassing elements (42) in a lower region for injecting the alternative environment into a bulk material in the silo, and a demand gas exchanger for receiving material discharged from the silo as it is transported to the filling station for filling, the demand gas exchanger comprising a gassing region with additional gassing elements. 20. System according to claim 1, further comprising a gassing rail (10) comprising a first assembly (91) and a second assembly (92): wherein the first assembly (91) is adapted to be mounted relative to the conveyor (59) and to releasably support the second assembly; and wherein the second assembly (92) is designed to be detachably supported by the first assembly and wherein it comprises the distribution manifold (13). 21. The system of claim 20, further comprising quick-disconnect clamps (75) which cooperate with and releasably connect the first and second assemblies (91, 92). 22. A system according to claim 20, wherein in use the width of the distribution manifold (13) is about half the width of the container opening or less. 23. The system of claim 20, wherein the distribution chamber (11) comprises cooperating portions of the first and second assemblies (91, 92) when the second assembly (92) is mounted such that the interior of the distribution chamber is accessible when the second assembly is dismantled. 24. The system of claim 20, wherein the distribution manifold (13) is removably attached to the second assembly (92). 25. System according to claim 20, further characterized by at least one longitudinally extending exhaust duct (37a, b) for receiving and conveying exhaust gases, the exhaust duct comprising connections (39a, b) for admitting the exhaust gases and an outlet (83) for attaching the exhaust duct to an exhaust system. 26. The system of claim 20, wherein the distribution manifold (13) comprises openings. 27. The system of claim 20, wherein the distribution manifold (13) comprises a wire grid. 28. The system of claim 1, wherein the system comprises a vessel (40; 60) for processing a particular material by means of an alternative ambient gas, characterized by: a plurality of gassing elements (80) with elongated distribution surfaces for passing the alternative ambient gas into the areas surrounding the distributors; and wherein the gassing elements are distributed around the circumference of the vessel, wherein the elongated distribution surfaces extend into the interior of the vessel in such a way that the end of each elongated distribution surface is located in the vicinity of at least one other gassing element with an elongated distribution surface. 29. The system of claim 28, further characterized by: an on-demand processor for removing the first entrained atmosphere from a particulate material flow in real time, the on-demand processor comprising a vessel having a restricted internal volume for receiving a flow of the particulate material as part of a processing system. 30. The system of claim 29, further characterized in that each elongate distribution surface of each gassing element (80) creates a gassing region within which the selected alternative environment displaces the first entrained atmosphere from a portion of the incoming particulate material flow; and that the gassing elements are arranged such that the gassing regions associated with adjacent distributors overlap, resulting in an effectively continuous environment displacement zone extending across the entire width of the vessel interior perpendicular to the direction of flow of the particulate material. 31. The system of claim 28, further characterized in that: each elongated distribution surface of each gassing element (80) creates a gassing area within which the inert[*]gas displaces entrained oxygen from the incoming particulate material; and that the gassing elements are arranged in such a way that the gassing areas assigned to adjacent distributors overlap, resulting in an effectively continuous displacement zone which extends over the entire width of the vessel interior perpendicular to the direction of movement of the particulate material. 32. The system of claim 28, further characterized by two or more substantially coplanar levels of gassing elements (80), each comprising a plurality of gassing elements. 33. The system of claim 28, wherein the elongated manifolds are substantially radial with respect to an axis of the vessel. 34. The system of claim 33, wherein the elongated manifolds are angled to the direction of flow of the particulate matter through the vessel. 35. The system of claim 28, wherein the vessel is a silo (40) having sufficient internal volume configured to store large quantities of the particulate material and to expose the particulate material to the inert gas for extended periods of time to displace oxygen. 36. The system of claim 28, wherein the vessel is a limited volume on-demand processor configured to convey flowing particulate material in close proximity to the manifolds with minimal residence time within the vessel, while in the essentially all of the oxygen is displaced from the material as it flows through the vessel. 37. The system of claim 35, further comprising a vent to vent at least a portion of the displaced gases. 38. The system of claim 36, further comprising a vent to vent at least a portion of the displaced gases. 39. The system of claim 1, comprising: a pre-cleaning system (1) for providing a controlled flow of a selected alternative environment into a series of open containers (50) to thereby displace oxygen-containing atmosphere within the containers with the alternative environment, a filling station (2) to receive the open containers from the pre-cleaning system and to fill the containers with portions of at least one bulk material (9), and a sealing station (6) to permanently seal the filled containers (52), characterized in that the filling station comprises a demand processor (5) with a controlled environment to remove oxygen from the bulk material in real time as it flows to a filling device to fill the open containers (50), and characterized by a gas space cleaning rail (3) and a conveyor (59) for transporting filled containers (52) from the filling station to the sealing station, the gas space cleaning rail comprising at least one gas distribution chamber (11). 40. The system of claim 28, wherein each gassing element (80) comprises: a mounting collar to cooperate with an opening; a gas inlet port supported by and on a first side of the mounting collar; an elongated gas distributor on a second side of the mounting collar, the gas distributor comprising a support frame extending from the mounting collar and a gas permeable member supported by the frame and partially defining a distribution channel operatively connected to the gas inlet; wherein the gas permeable element comprises at least an upper portion which is generally tapered in a direction transverse to the extended axis of the gas distributor; and wherein the elongated gas distributor has a cross-section that allows the distributor to pass through the opening. 41. The system of claim 40, wherein the gas permeable element comprises a fine wire mesh, and wherein gas flow from the manifold is substantially laminar. 42. The system of claim 40, wherein the gas permeable element is removable from the support frame to allow access to the interior of the distribution channel. 43. The system of claim 40, wherein the gas permeable element further comprises a lower portion providing an additional gas permeable surface area having generally parallel sides. 44. The system of claim 1, further comprising: a main device with a filling station (2) and an environment processor (5) for packaging a predetermined amount of material in each container (50) such that the container interior and the packaged material have a reduced oxygen environment, a sealing station (6) to permanently seal the filled containers, and a main transport system with a controlled/regulated environment for transporting filled containers (52) to the sealing station, characterized by: an independent environmental processing station for separately processing a smaller number of containers to remove substantially all of the oxygen from the interior of the containers; and a further transport system to transport processed containers from the independent environment processing station, the further transport system merging into the main transport system with controlled/regulated environment. 45. A system according to claim 44, wherein the main transport system with controlled environment comprises a conveyor (59) and a main gas space cleaning rail (3) with at least one gas distribution chamber (11) which is substantially aligned in the direction of movement of the filled containers (52), the distributor (13) providing a controlled flow of a selected alternative environment into the containers; and wherein the further transport system comprises a further gas space cleaning rail (14) with a portion thereof located in the vicinity of the main gas space cleaning rail. 46. The system of claim 44, further comprising: Devices to detect underfilled containers with less than the predetermined quantity of bulk material; means (110) for separating the underfilled containers from the conveyor (59) to the independent environmental processing station and for covering the underfilled containers; and wherein the underfilled containers can be filled to the predetermined amount, wherein the containers are processed by the independent environmental processing station to remove substantially all of the oxygen from the interior of the covered container, and wherein the containers are at least partially transported by the further transport system to the sealing station (6). 47. A method for flushing oxygen from open containers (50, 52) moving along a conveyor (59) in a running direction, comprising the steps of: providing a gas distribution chamber (11) extending longitudinally along the conveyor, the gas distribution chamber comprising an inlet (12) receiving an alternative ambient gas from a source and a distribution manifold (13), the distribution manifold comprising at least one flow resistance region; Passing the containers along the gas distribution manifold for a period of time; Flow of an alternative ambient gas through the flow resistance region and into the container; supplying a flow of alternative ambient gas through the longitudinally oriented distribution manifold having a width less than the width of the vessel opening, the incoming flow of alternative ambient gas entering the vessel; characterized in that the flow resistance region has a different flow resistance across its width to provide a different flow rate of the alternative ambient gas into the container (50, 52), the flow of the alternative ambient gas creating an inflow and outflow gas pattern which is constant for the entire time the container is being purged in essentially continuous and essentially in a permanent state. 48. The method of claim 47, wherein the width of the distribution manifold (13) is about one-half or less than the width of the container opening. 49. The method of claim 47, wherein the width of the distribution manifold (13) is about one quarter or less than the width of the container opening. 50. The method of claim 47, wherein supplying a flow comprises: supplying a higher velocity flow of alternative ambient gas through the gas distribution manifold (13) and through the open tops into the containers (50, 52) through a region of lower flow resistance oriented parallel to the direction of travel while the containers are located along the gas distribution manifold, and supplying a flow of alternative ambient gas at lower velocity through the gas distribution manifold and along the vessels, through a region of higher flow resistance, which is oriented parallel to the direction of travel, while the vessels are located along the gas distribution manifold. 51. A method according to claim 47, comprising receiving gas leaving the containers (50, 52) through ports (39a, b) in a return gas chamber (37a, b) arranged along the distribution manifold (13). 52. The method of claim 47, wherein the distribution manifold (13) is covered by a screen providing a substantially laminarized flow. 53. A method according to claim 47, comprising providing a longitudinally extended exhaust duct (37a, b) near the gas distribution manifold (13), with connections (39a, b) to admit gases into the exhaust duct and with an outlet (38) to attach the exhaust duct to an exhaust system, and receiving and conveying away at least a portion of the gases blown out from the container interiors through the exhaust duct. 54. The method of claim 53, comprising generating a different velocity inert gas flow by means of the distribution manifold (13) having a different flow resistance across its width to provide at least two different flow rates of an alternative environment into the containers (50, 52). 55. A method according to claim 47, comprising providing a processor for receiving particulate material (9), comprising: causing the particulate material to flow through a processor (5) having a processing region; Providing a plurality of gassing elements (42, 43) having elongated distributor surfaces for directing the alternative ambient gas into the regions of the particulate material flow adjacent to the distributors, the elongated distributor surfaces extending into the processing region of the processor such that the end of each distributor is located near at least one other gassing element distributor; wherein each elongated distribution surface of each gassing element which creates a gassing area within which the Alterna tive ambient gas displaces the first entrained atmosphere from a portion of the particulate material flow, and wherein the gassing elements are arranged such that the gassing areas associated with adjacent distributors overlap, resulting in an effectively continuous ambient displacement zone extending across the entire width of the processing area perpendicular to the flow direction of the particulate material.