HK1036569A - Method and device for recycling and decontaminating bag type objects such as disposable gloves for white rooms - Google Patents

Description

Method and apparatus for recycling and cleaning bags for clean room

The present invention relates generally to the decontamination of pouches made of natural materials (latex), or plastics such as polyethylene or polypropylene, or non-porous or microporous polymers, which are typically discarded after use, and more particularly, they are used in a controlled atmosphere environment.

In particular, the invention relates to a method and apparatus for recovering and decontaminating said disposable bags for use in clean rooms.

Thus, the object of interest may be a plastic bag formed of natural or synthetic latex, vinyl, or any other polymer. It is also possible to include all articles which are present in the form of pouches whose water permeability is very low or zero.

In fact, the only exceptions are those items that are water permeable, such as textiles or any other item that can be washed and dried effectively, typically in domestic or industrial washing and drying machines.

Drying the non-porous pouch is difficult because the water introduced into the pouch during washing is very difficult to remove. The main factor preventing drying is that the surface tension between the two thin inner layers due to the non-porosity of the relevant material will "catch" water and not allow them to evaporate through the pouch.

This applies to gloves currently used in clean rooms, which are discarded each time the wearer leaves the clean room, that is to say approximately every second clock.

The document DE1642128 discloses a method for recycling and decontaminating e.g. disposable gloves.

The method according to the invention enables gloves to be recycled several times and reused like new, non-degraded gloves, thus reducing their average cost and the proportion of waste items.

It can be seen that the method and apparatus according to the invention relate to an article particularly intended for use in a controlled atmosphere, for which the nature of the decontamination solution and cleaning agent used is of great importance. Some decontamination solutions are prone to damage to the material and residual contamination of the articles by the cleaning agents may occur which is incompatible with their role in the controlled atmosphere.

Up to now, purification has been performed on industrial machines having deionized, filtered water and a detergent containing nonionic. Washing parameters such as time, temperature, spin-drying speed and number of cycles are varied depending on the volume of water and the amount of detergent used.

Furthermore, to prevent water from entering the pouches, so as not to cause drying problems, the pouches are tied into a bundle so that they are sealed.

In this case, the drying is carried out in a conventional industrial dryer. The only factors that determine the drying time are the temperature and the amount of material placed in the drum.

The treatment results directly from the cleaning of the textile articles used in a controlled environment, whereas the treatment will be suitable for cleaning only the outer surface of the bag.

Now, in the case of gloves or bags that were once used in a controlled atmosphere, it is no longer satisfactory to wash only one of the two surfaces, it being necessary to remove from the other the sweat left behind by the user and soiled as a result of the operation carried out, since the glove must be restored to its original shape, both physically and without particles and bacteria.

The present invention makes it possible to avoid these drawbacks by providing a method and a device by which both surfaces, inside and outside, can be washed, thus making it possible to obtain a re-used and/or purified product, but at a lower cost than the same product when new, and at the same time it is possible to limit the industrial waste of the materials concerned.

Accordingly, a first object of the present invention is a method for recycling and decontaminating pouches, such as disposable gloves for use in clean rooms, comprising:

sorting out the bags without marks, counting and performing computer processing tracking;

the bag-shaped objects are washed and purified by washing and rinsing water and utilizing equipment, and the bag-shaped objects are processed into pollutants-free objects;

transferring the washed bag in a sealed, modified container to a dryer in which a product contamination prevention device is installed;

transferring the dry pouches to a packaging station in a sealed container where they are introduced into a packaging bag;

and outputting the packaged bag-shaped object to a sealed container.

Another main object of the present invention is to provide a device that allows the recovery and cleaning of bags, such as disposable gloves, used in clean rooms, for carrying out the above method, in which a washing machine, placed downstream of the sorting station, has a discharge opening in the sealed container, in which the air is up to specification, while the bags move in the direction of the dryer, also located in the sealed container.

Other particular features and advantages of the invention will appear from the following description of an exemplary embodiment, in which reference numerals indicate schematically a recovery and purification device according to the invention.

Figure 1 shows schematically a glove recovery and cleaning apparatus.

The gloves with the adhered labels that are not washed off with water and solvent are collected in a sorting station 1. Gloves are manually or automatically fed out to the right and sorted by size, in the event that unwashed stains, or nicks or tears are not considered. Gloves considered non-recyclable were discarded. Because of the computerized tracking of the indicia, the number of items of each size, the number of discarded items, and the number of recycles of sorted and deemed appropriate items may be calculated.

The monitoring with computer processing can also be determined in real time: who the customer is used, and how the size used will develop, thereby enabling the manufacturer to perform production activities at the actual consumption. Furthermore, it makes it possible to process the documents in the distribution sector and to automatically readjust the new items for each customer, so as to meet their industrial requirements and to monitor them in modules, whether static or dynamic, all the parameters required and necessary for the correct operation of the module, which will be stopped when one of them no longer meets the specifications that allow decontamination, which correspond to the industrial requirements of the destination of the recycled product.

At the outlet of the sorting station 1, the gloves 2 are guided (dashed arrow) towards a washing machine 3 and enter therein through a door 4. The washing machine disposed downstream of the sorting station is supplied with water from the ultrapure water production apparatus 5. The water is obtained by filtration in activated charcoal of at least 5 microns. The washing water is charged with a detergent which has at least one of the nonionic or cationic surfactants of the quaternary ammonium type, or a mixture of these surfactants. At least one disinfectant may also be added, the disinfectant having bactericidal, virucidal, fungicidal and oxidizing properties. The water is deionized or permeated.

The rinse water directed to the washing machine is preferably filtered to at least one micron. The purified water is deionized and filtered to at least 0.45 microns.

The washing machine 3 is equipped with a non-return valve 6 on the waste water discharge valve 7 and at least one filter element (not shown) at the machine outlet, in order to filter to at least one micron. All the elements for fluid circulation are made of non-polluting materials, that is to say, they allow only a very small release of metal ions or particles in the water when the different parts come into contact with it.

The washing machine is also provided with a discharge door 8 open towards the sealed container 9, which will limit the particulate pollution generated by the ambient gases.

Gloves placed in a washing machine are subjected to at least one washing operation, at least one rinsing operation, at least one cleaning operation, and at least one spin-drying operation.

After the gloves have been retrieved through the discharge door 8, they are moved through the container 9, as indicated by the solid arrow, towards the dryer 10, inside which the access door 11 of the dryer is located.

The dryer 10, placed in a sealed device, allows mechanical agitation of the product. Wherein also recycled clean hot gas from the supply 12 is provided, filtered to at least 1 micron and generating a negative pressure of at least 50 millibar (mbar). In this way it is possible to dry pouches with no or little porosity for a certain time and to maintain a competitive product. It is also possible to provide a device for ionizing air that makes it possible to reduce the residual particulate contamination on the pouch or glove, in particular to significantly reduce the number of particles with a size of less than 1 micron, or possibly to modify the electrostatic charge of the pouch or glove, according to the established industrial requirements.

After the drying operation, the gloves are still introduced (along the dashed arrow) in the sealed container 9 into a packaging station 13 downstream of the dryer 10 in said container. Thus, the bag or glove is introduced into a bag or blister pack made, for example, of polyethylene or polypropylene, which is clean in terms of particles, which is made of disposable or reusable packaging, and which uses sealing welding and under partial vacuum.

Once packaged, the product is fed out of the sealed container 9.

In the container, where washing, drying and packaging operations are carried out and transfer between stations is carried out in sequence, where the equipment necessary for carrying out the different manual operations and jobs is also installed, the air should be controlled and supplied at a rate of at least 10 changes per hour as clean and fresh air. This environment, commonly called an "absolute clean room," is necessary to ensure that the product, especially the product being processed by the apparatus, is clean in terms of particulates. The operators responsible for these operations therefore wear at least gloves, special hats and single-piece coats, and they have features similar to those used by persons in absolute clean rooms according to the regulations in force. If some operations are performed by automated systems, they should also have these characteristics so as not to be contaminated.

Thus, the method according to the invention provides a technically and industrially competitive solution, enabling the recycling of pouches or gloves with no or little holes.

In fact, the present invention enables to effectively wash both sides of the product by some means, in particular by a specific drying technique, i.e. allowing the evaporation of the liquid phase present in the pouch or glove, compared to the methods used up to now, while reducing the cost price of the product due to the recycling operations carried out compared to the new products.

This method also reduces the waste of dumping the products in the ground or in incinerators, allowing their recycling, so that their reuse by said method is somewhat at a low cost price as is currently carried out on a large scale in the case of porous materials, such as textiles.

Claims (10)

1. A method for recycling and decontaminating pouches (2), such as disposable gloves, used in clean rooms, characterized in that it comprises:

sorting out the bags without marks, counting and performing computer processing tracking;

the bag-shaped objects are washed and purified by washing and rinsing water and utilizing equipment, and the bag-shaped objects are processed into pollutants-free objects;

transferring the washed bag in a sealed, modified container (9) to a dryer in which means (11) for preventing contamination of the product are installed;

transferring the dried pouches to a packaging station (13) in a sealed container where they are introduced into a package;

the packaged bag is delivered out of the sealed container (9).

2. A method of recycling and purification according to claim 1, characterized in that the bag (2) is delivered and sorted to the right according to size, after being individually marked and not washed out by water and solvents.

3. A recovery and purification process according to claim 1, wherein washing water and a detergent are added, the detergent having at least one of a nonionic or cationic surfactant, or a mixture of such surfactants; and at least one disinfectant having germicidal, virucidal, fungal and oxidative properties.

4. A recovery and purification method, as in claim 1, characterized in that the bag (2) is subjected to at least one washing operation, at least one rinsing operation, at least one purification operation, and at least one spin-drying operation.

5. A recovery and purification method according to claim 1, characterized in that the circulating hot gases filtered to at least 1 micron and the underpressure of at least 50 mbar are provided in the dryer (10).

6. A recycling and purification method according to claim 1, characterized in that the particulate contamination of the bag (2) is reduced by changing the electrostatic charge.

7. A recycling and purification method according to claim 1, characterized in that the bag (2) is introduced into a bag made of a hermetically welded and disposable or reusable packaging under partial vacuum.

8. An apparatus for recycling and cleaning bags, such as disposable gloves, used in clean rooms, which implements the method according to claims 1-7, characterized in that a washing machine (3) arranged downstream of the sorting station (1) has a discharge door (8) in a sealed container, in which the air is to be brought to the requirements, in which the bag (2) is moved in the direction of the dryer (10), and in which a packaging station (13) downstream of the dryer is also located.

9. A recovery and purification device, according to claim 8, characterized in that the washing machine (3) is equipped with a non-return valve (6) on the waste water discharge valve (7) and has at least one filter cartridge, at the drum outlet of the machine, capable of filtering to at least 1 micron.

10. A recovery and purification apparatus according to claim 9, characterised in that the clean hot air circulated through the dryer (10) comes from a supply source (12) outside the sealed container (9).