WO2001040058A2 - Method and device for emptying pressure packs - Google Patents

Abstract

The invention relates to a method and device for carrying out the controlled emptying of at least one constituent of the contents from pressure packs (2) comprising the following method stations: in an intense cooling station (10), the pressure packs (2) are subjected to an intense cooling below a temperature that is lower than the solidification temperatures of the constituent of the contents contained in the pressure pack; in an opening station (18), the pressure packs (2) are opened, whereby the constituent is in a solidified state of aggregation, and; in an ejection and sorting station (20, 24), the solidified constituent is removed from the pressure pack (2) and is transferred separately from the remnants of the pack into a collecting container (36).

Description

Method and device for the controlled emptying of at least one component of the contents from compressed gas packs

The invention relates to a method and a device for the controlled emptying of at least one component of the content from compressed gas packs.

With regard to the background of the invention, it should be noted that compressed gas packs in accordance with the relevant technical rules of the Association of Technical Surveillance Associations, Essen, are understood to mean certain containers for single use, including their filling and their removal device. These are typically everyday products, such as aerosol cans, so-called sprays or spray cans, which contain a wide variety of contents from deodorants to insecticides and lubricants to spray cream, and the like. The content components consist on the one hand of a blowing agent and on the other hand a generally so-called "active ingredient. The blowing agents can be compressed gaseous blowing agents, liquid gas blowing agents, multi-component blowing agents, etc. The blowing agents can also act as a solvent for the actual active ingredient content fulfill.

The active substance content in the compressed gas pack can be present, for example, as a pure liquid, as a liquid mixture, or as a solution, suspension, dispersion, emulsion of an actual active substance in a solvent or carrier. Depending on the product, there is a wide range of possible variations. The problem regularly arises of having to regain or dispose of the entire content or at least individual components of it in a controlled manner. This is the case, for example, if completely filled compressed gas packs cannot reach the market due to overcapacities, overlay or production errors. There is also the problem of compressed gas packs coming back from the trade, the contents of which have exceeded the shelf life.

So far, attempts have been made to spray the contents of the pack under pressure more or less in a controlled manner and, if necessary, the components. to catch with the blowing agent. This is highly problematic in terms of disposal technology and environmental compatibility, so that these compressed gas packs are generally not emptied, but treated as special waste and thermally removed.

The invention is therefore based on the object of specifying a method and a device for emptying compressed gas packs, with controlled and environmentally friendly work.

This task is solved by a process with the following process steps:

Freezing the compressed gas pack to a temperature which is below the solidification temperature of the content component (s) to be emptied,

open the aerosol can, this content component being in a solidified state, - Removing the solidified content component from the aerosol can and

- Transfer the content component and the remnants of the compressed gas pack into separate collection containers.

Accordingly, a device according to the invention for the controlled emptying of at least one component of the contents from compressed gas packs is provided with:

a conveying device for conveying the compressed gas packs between and through the individual stations,

a freezer station for freezing the compressed gas pack to a temperature which is below the solidification temperature of the content component to be removed, an opening station for opening the pressurized gas packs when the content component has solidified,

an ejection station for removing the solidified content component from the respective compressed gas pack, and

- A sorting station for transferring the remnants of the compressed gas packs and the solidified content component into separate collecting containers.

The key point of the method according to the invention and the corresponding device lies in the deep-freezing of the compressed gas pack, as a result of which the content can be manipulated without problems for the further treatment steps. In particular, these treatment steps after opening the pressurized gas pack can be essentially mechanical, so that the content components to be emptied and the pack remnants are simple can be separated by appropriate handling steps. The active ingredient and propellant content of the can are preferably frozen at a corresponding temperature by freezing. It can then be handled as a common mass block with the active ingredient content, regardless of whether the various components are attributable to the liquid or gaseous phase of the content.

Preferred process and device features are specified in the subclaims, such as the freezing of the compressed gas packs in a continuous freezer bath of liquid nitrogen. In the present context, liquid nitrogen is a very suitable coolant, since it is available on an industrial scale and is therefore inexpensive. Nitrogen also has protective gas properties, which considerably simplifies the handling of the often flammable active ingredient contents of compressed gas packs.

A particularly preferred trick is also given by the wall-side heating of the frozen compressed gas packs, which leads to thawing of the solidified content components at their interface with the pack wall and thus to the formation of a sliding film for the content block. This means that after opening the package it slides out of the package particularly easily and reliably due to its own weight.

Further features, details and advantages of the method according to the invention and the device provided therefor can be found in the following description, in which an exemplary embodiment of the invention is explained in more detail with reference to the accompanying drawings. Show it: 1 shows a schematic overall diagram of a system for the controlled emptying of an active substance content from aerosol cans,

2 is an enlarged side view of a conveyor belt device for aerosol cans running in the deep-freeze bath of the system,

3 is a view of the conveyor belt device according to FIG. 2 in the conveying direction, and

4 is a view of the ejection and sorting station of the system from viewing direction IV according to FIG. 1.

The general structure of the invention is to be explained with reference to FIG. 1 using an aerosol can disposal system. Thus, the system with the essential parts is encapsulated in a system housing 1, designated as a whole as 1, which is thermally insulated and essentially gas-tight. The aerosol cans 2 belonging to the compressed gas packs are charged via a charging station 3, in which the cans 2 are fed onto a first conveyor belt 5 from a presorting 4 (not shown). From there, the cans 2 enter a blow-through rotary valve 6, at the outlet opening 7 of which a guide track 8 for the cans 2, which is to be described in more detail with reference to FIGS. 2 and 3, connects. In Fig. 1, moreover, the loading station 3 is shown rotated again by 90 ° with respect to the main view in this figure in the area delineated by dashed lines.

The blow-through rotary valve 6 is supplied with a stream of nitrogen from a nitrogen stream on the side opposite the discharge opening 7. Gas supply 9 is acted upon in such a way that a can 2 lying in the discharge opening 7 is blown out of the rotary valve 6 and pushed onto the guide track 8. This leads into the system housing 1 and there into the freezer station 10 via a type of chute 11. The freezer station 10 has a freezer bath 12 made of liquid nitrogen, the temperature of which is -196 ° C. Liquid nitrogen is supplied from a corresponding storage container or a refrigerator via a nitrogen connection 13. The level of the liquid nitrogen in the deep-freeze bath 2 is monitored by a level sensor 14. In the freezer station 10, an endless conveyor belt device 15 is provided, which is assigned to the guideway 8 and ensures that the aerosol cans 2 are transported through the freezer bath 12. Here, too, the more precise structure will be explained in more detail with reference to FIGS. 2 and 3.

At the end of the deep-freeze bath 12, the cans are transferred to a third conveyor belt device 16, which only serves as an intermediate store for the frozen cans. From there, the cans arrive at a further conveyor belt device 17, which provides for further transport of the cans 2 through an opening station 18 via a heating station 19 to the ejection and sorting station 20 located at the end of the system. All conveyor belt devices 15, 16, 17 are otherwise equipped as endless conveyor belts with corresponding deflection rollers 21 and drive motors 22. Your conveyor belts 23 carry gripping elements 24, each holding a can 2 and conveying further.

In the opening station 18, a circular saw 25 with a saw blade 26, drive motor 27 and holding punch 28 for the cans 2 is provided. The circular saw 25, the saw blade 26, for example, in the center of the conveyor belt device 16 is arranged, the can 2 fixed by the holding stamp 28, together with its contents, sawn up in the middle and separate into two parts. It is understood that in the arrangement of the saw blade 26 shown, the conveyor belt 23 of the conveyor belt device 16 is divided in two in the longitudinal direction and has a gap in the center.

After the opening station 18, a sealing lock 29 is provided, with which the cold zone of the system housing 1 with freezer station 10, conveyor belt device 16 and opening station 18 is thermally separated from the heating station 19 designed as a warm zone and ejection and sorting station 20, that the heat transport from the heating station 19 in the opening station 18 is largely contained under practical aspects.

The heating station 19 has an infrared radiator 30, the heating power of which is set in such a way that the solidified contents of the can are heated via the can wall in such a way that a lubricating film is formed by thawing at the interface with the can wall. If the warm zone has a sufficiently large temperature difference from the cold zone, an IR radiator can also be omitted if necessary and only thawed the solidified active ingredient content due to the temperature prevailing there.

At the end of the conveyor belt device 17, the sorting station 20 is arranged, which in FIGS. 1 and 4 only has grippers 31, which are arranged only schematically, for the can halves 52 created by sawing the cans 2. In Fig. 1, these grippers 31 are below the conveyor belt device

17 - in other words, with regard to the flow diagram for aerosol can treatment according to the conveyor belt device 17 - is shown. The real che mechanical structure is however apparent from Fig. 4, where the grippers 31 are shown above the conveyor belt device 17. As can also be seen from this FIG. 4, the sorting station 20 has a central drop funnel 32 and further drop funnels 33 on each side thereof. The downward-facing openings of these drop funnels 32, 33 can each be closed by means of a lock flap 34 designed as a slide.

Finally, collecting containers 36, 36 ″ which can be moved with a lifting truck 35 are provided and can be connected below to the fall funnels 32, 33. The collecting containers 36, 36 'and the fall funnels 32, 33 are to be connected to one another in a sealed manner with respect to the environment.

The system housing 1 is also provided at various positions with various connections and a nitrogen system coupled to it. Thus, at the end of the cold zone in the area of the opening station 18, a suction device 37 is provided for the cold nitrogen gas that evaporates over time from the freezer bath 20. A blower 39 with a motor 40 sucks off the gas via a sluice flap 38 and conveys it via a connecting line 41 on the loading side into the feed line 42 leading from the nitrogen gas supply 9 to the cellular wheel sluice 6 a nitrogen outlet 44 is provided in the atmosphere. The lock flap 43 is closed and opened by a motor 45, which is actuated by a pressure control, not shown. The gas pressure determined by a pressure sensor 46 above the deep-freeze bath 12 is used as the control variable for the pressure control. Before the process sequence for aerosol can disposal is described, the structure of the guideway 8 in the deep-freeze bath 12 must be explained with reference to FIGS. 2 and 3. This guideway 8 consists of a plurality of rods 47, each running parallel to and at a distance from the conveying direction 11, which are arranged on an imaginary circle 48. The diameter of the latter corresponds essentially to the specified maximum diameter of aerosol cans 2 which are to be handled in the system. The rods 47 are supported on the outside by part-ring-shaped holders 49. The holders 49 are broken through between the two uppermost rods 47 ', so that fork-shaped feed elements 50 can engage in the area between the rods 47 from above. These feed elements 50 are attached to the conveyor belt device. With their fork ends 51 they strike the upper shoulder around the head of aerosol can 2 and push it further on rods 47. Due to the open rod construction, the liquid nitrogen in the deep-freeze bath 12 can reach the can unhindered and ensure its deep-freezing. The rod guide construction 8, 47, 47 'shown furthermore, in conjunction with the feed elements 50 and the conveyor belt device 15, prevents the cans 2 from floating in the deep-freeze bath.

In the following, the disposal method is briefly explained as it takes place in the device shown in FIG. 1.

About the blow-through rotary valve 6, the can 2 located in the discharge opening 7 is moved by blowing nitrogen out of the gas supply 9 onto the guideway 8, on which the respective can is moved forward on the slide 11 due to gravity until it comes into contact with the conveyor belt device 15. This takes over the guideway 8 each can and guides them through the deep-freeze bath 12 with the aid of the feed elements. The throughput time through the liquid nitrogen is dimensioned such that the liquid and gaseous phase - ie the active substance content together with the propellant - solidify to form a mass block 53. After exiting the freezer bath 12, the atmosphere in the system housing 1 in the area of the following conveyor belt device 16 and the opening station 18 is so cold that the contents of the cans 2 remain frozen. The cans placed on the conveyor belt device 16 are completely separated into two can halves 52 with the aid of the circular saw 25, in which half a mass block 53 of solidified active substance content and propellant is then contained.

As already mentioned, the can halves 52 are heated in the heating station 19 in such a way that the respective mass block 53 thaws at the interface with the can wall and forms a lubricating film from its liquid active substance content.

In the sorting station 20, the can halves 52 with the mass blocks 53 are packed by the grippers 31, lifted off the conveyor belt device 17 and rotated, as shown in the middle in FIG. 4. The grippers 31 thus serve as an ejection device for the mass blocks 53 from the can halves 52. The mass blocks 53 namely fall past the conveyor belt device 17 into the central drop funnel 32 and further into the central collecting container 36. Then the grippers 31 each follow spent outside until they are arranged above the side drop funnels 33. There the can halves 52 can be released. These fall into the respective external collecting container 36 '. Since the collecting containers 36, 36 'and the sorting station 20 belong to the warm zone of the plant, the mass blocks 53 thaw in the central collecting container 36, as a result of which the active substance content becomes liquid and the propellant evaporates. This separates the content components back into the liquid and gaseous phases. The propellant can be fed to a corresponding preparation via a propellant suction 54 connected to the sorting station 20. The propellant suction 54 consists of a suction 56 which opens into the sorting station 20 via a lock flap 55. A motor blower 57 is provided in the suction line 56, which ensures that the propellant is drawn off.

It should be mentioned that the collecting container 36 has a flushing connection 58, through which pure nitrogen can be blown in before the docking of the collecting container 36 to the drop funnels 32, 33 for flushing in order to render the interior of the collecting container inert.

Claims

claims 1. Method for the controlled emptying of at least one component of the content from compressed gas packs, characterized by the following method steps: Freezing the compressed gas pack (2) to a temperature which is below the solidification temperature of the content component of the pressurized gas pack (2) to be emptied, Opening the compressed gas pack (2), this content component being in a solidified state, - Removing the solidified content component (53) from the compressed gas pack (2) and - Transfer the solidified content component (53) and the remnants of the compressed gas pack (52) into separate collecting containers (36). 2. The method according to Anspmch 1, characterized in that the compressed gas pack (2) is frozen in a continuous deep-freeze bath (12), in particular in a bath of liquid nitrogen. 3. The method according to Anspmch 1 or 2, characterized in that the compressed gas pack (2) is sawn open. 4. The method according to any one of claims 1 to 3, characterized in that the compressed gas package is heated on its wall before the content component (53) is removed in such a way that the solidified content component (53) thaws at its interface with the can wall to form a lubricating film. 5. The method according to any one of claims 1 to 4, characterized in that the entire process takes place under a nitrogen atmosphere in a practically closed system (1). 6. The method according to any one of claims 1 to 6, characterized in that during freezing together with the at least one content component also solidify one or more propellant components in the can, the content components and propellant thawing in the collecting container (36) by liquefying the active ingredient - Separate the content and the evaporation of the blowing agent. 7. Device for the controlled emptying of at least one component of the content from a compressed gas pack with: a conveying device (5, 8, 15, 16, 17) for conveying the compressed gas packs (2) between and through the individual stations (3, 10, 18, 19, 20), - a freezer station (10) for freezing the compressed gas packs (2) to a temperature which is below the solidification temperature of the content component to be removed, - an opening station (18) for opening the compressed gas pack (2) when the content component (53) has solidified, - An ejection station (31) for removing the solidified content component (53) from the compressed gas pack (2), and - A sorting station (20) for transferring the remnants (52) of the compressed gas pack and the solidified content component (53) into separate ones Collecting container (36). 8. The device according to Anspmch 6, characterized in that the conveying device has a plurality of endless conveyor belt devices (5, 15, 16, 17) connected in series. 9. Apparatus according to Anspmch 6 or 7, characterized in that the freezer station has a nitrogen bath (12) through which the compressed gas packs (2) can be conveyed by means of a conveyor belt device (15). 10. The device according to Anspmch 8, characterized in that the conveyor belt device in the deep-freeze bath (12) has a coolant-permeable guide track (8) on which the pressure gas packs (2) by means of feed elements (50) engaging in the guide track (8) on an endless conveyor belt (15) can be transported further. 11. Device according to one of claims 6 to 9, characterized in that the opening station (18) has a sawing device, in particular circular sawing device (25). 12. The device according to one of claims 6 to 10, characterized in that a heating station (19), in particular an infrared radiator device (30) is arranged after the opening station (18). 13. Device according to one of claims 6 to 11, characterized in that the ejection and sorting stations (31, 20) have a gripper-like manipulation device (31) for the remnants (52) of the compressed gas pack, by means of which the solidified content component (53 ) the compressed gas pack (2) in a first collecting container (36) and the Remains (52) of the compressed gas pack can be sorted into at least one second collecting container (36 '). 14. Device according to one of claims 6 to 13, characterized in that the collecting containers (36, 36 ') are gas-tight with the sorting station (20) can be coupled. 15. Device according to one of claims 6 to 14, characterized in that in the region of the sorting station (20) a propellant suction device (54) is connected, by means of which the evaporated Blowing agent component can be removed to a blowing agent treatment device.