FR3066128B1 - METHOD FOR ENHANCING CIGARETTE MEGOTS - Google Patents

Abstract

The invention relates to a method of upgrading cigarette butts (40), composed of a filter (41) and organic material (32) composed of ash, paper sheets and tobacco, said filter (41) being composed cellulose acetate (33) and paper (34), characterized in that the method comprises the following steps of: a) first grinding (22) from cigarette butts (40) in a first mill to separate the filter (41) of the organic material (32); b) sieving (23) the filter (41) and the organic material (32) to recover the cellulose acetate (33) contained in the filter; c) washing (24) the filter (41) to separate the cellulose acetate (33) and the paper (34) with water in a wash tank; d) decontamination washing (25) of the cellulose acetate (33) with water in a decontamination tank to obtain the cleaned cellulose acetate (37); e) recycling the water (26) of steps c) and d) by a water recycler; f) pre-cooking drying (27) to obtain dried cellulose acetate (38); g) second milling (28) to obtain fibrous fine particles of cellulose acetate (39).

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a method of upgrading cigarette butts. It applies, in particular, to the recovery of toxic waste contained in cigarette butts and in particular to the recycling of cellulose acetate.

Waste recovery is a set of processes by which a material or organic waste is transformed into the purpose of a specific use such as recycling, in the long term to produce an income. Cellulose acetate is a plastic material and is in the form of fibers.

Collection areas are set up in companies, public places, streets, beaches, ski resorts, campsites ...

In one example, the collection areas are storage columns of cigarette butts. Thus, the collection is carried out for the recovery process.

STATE OF THE ART

The upgrading process is suitable for recycling the remaining cigarette butt after use. The cigarette butt consists of a filter composed in particular of cellulose acetate and a paper envelope. The cigarette butt filters absorb more than four thousand harmful chemicals with irritating, harmful, toxic, mutagenic and carcinogenic effects in the surrounding environment as they enter the smoker's respiratory system.

For the reasons presented above, each cigarette is therefore provided with a filter at one of its ends to retain some of the harmful chemical substances mentioned above. When the cigarette is consumed, the filter is placed in such a way that the smoke passes through the filter before reaching the smoker's lungs.

As a result, some of these harmful substances are trapped in the filter and contaminate the non-smoking cigarette part, otherwise known as a cigarette butt. Among the contaminants in cigarette butts are nicotine, benzene, toxic gases, ethylphenol, hydrocyanic acid, radioactive compounds and cellulose acetate, which is defined as the plastic material from which the filter is done.

The decomposition time of a cigarette butt is several years, up to fifteen years.

Cigarette butts are considered as hazardous for the environment, accounting for 40% of the waste in the Mediterranean Sea. Birds and marine animals die as a result of the direct indigestion of cigarette butts.

Some cigarette butts processing methods exist and provide a plastic product and a percentage of cigarette butts and plastics. However, there are traces of toxic residues in cigarette butts and therefore the product of this type of process.

One of the objectives of the invention is to provide a method for recycling cigarette butts in order to avoid having toxic residues in the product resulting from the process.

Another object of the present invention is to create a simple process to implement while respecting ecological constraints.

OBJECT OF THE INVENTION

The present invention aims to remedy these disadvantages. For this purpose, the present invention aims at a process for the recovery of cigarette butts, composed of a filter and of organic material composed of ash, sheets of paper and tobacco, said filter being composed of cellulose acetate and paper, characterized in that the method comprises the following steps of: - a) first grinding from cigarette butts in a first mill to separate the filter from the organic material; b) sieving the filter and the organic material from the first grinding step to recover the cellulose acetate contained in the filter; c) washing the filter for separating the cellulose acetate and the paper from the sieving with water in a washing tank; d) decontamination washing of the cellulose acetate with water in a decontamination tank to obtain the cleaned cellulose acetate; e) recycling the water of steps c) and d) by a water recycler; f) drying by precooking from the cleaned cellulose acetate to obtain dried cellulose acetate; - g) second milling from the dried cellulose acetate to obtain fibrous fine particles of cellulose acetate.

The process of upgrading cigarette butts makes it possible to produce fibrous fine particles of cellulose acetate that have been decontaminated and that can be used for the manufacture of various objects.

Thanks to these provisions, the sieving step allows the gradual separation of the waste. Indeed, tobacco, ash, paper sheets and filter are separated as and when, so it is easier and simple to recover cellulose acetate.

Through the filter washing step, the cellulose acetate is separated from the paper, allowing only the cellulose acetate to be recovered.

Washing in the decontamination tank causes the elimination of harmful pollutants retained by cellulose acetate. The analysis of the water contained in the washing tub and the decontamination tank shows a decrease in the quantities of harmful polluting substances. The recycling of water allows to have water already used without harmful substances. The invention is advantageously implemented according to the embodiments and variants described below, which are to be considered individually or in any technically operative combination.

In one embodiment, step d) comprises two other depollution tanks for decolluting the cellulose acetate, the cellulose acetate passes from one decontamination tank to another.

In one embodiment, step d) is repeated three times. The triple repetition of washing in the three depollution tanks leads to an improvement in the quality and cleanliness of the finished product.

In one embodiment, the washing of the filter of step c) and the scrubbing wash of step d) is done with a solvent, preferably water.

In one embodiment, the recycling of the water of step e) is carried out in a closed circuit.

In one embodiment, the water rebreather of step e) comprises a coagulation step and a flocculation step. The water recycler processes up to 1000 liters per cycle in order to recycle the water from the washing and decontamination tanks. The water rebreather allows the regeneration of water by clarifying loculation.

In one embodiment, the method comprises a step h) of thermo-compression in a thermo-compression press. The cellulose acetate is melted to make plates of the desired thickness thanks to the two hydraulic cylinders, this method combines a heating station and a cooling station. The working cycle of the thermo-compression press is automatic and programmable. The invention also relates to a process for the production of cellulose acetate plates based on cellulose acetate.

Thus, the plastic plates are reusable and allow the manufacture of pallet handling and / or street furniture. Many objects can be created from plastic sheets such as under glass, parquet, furniture, advertising media, outdoor ashtrays and flower pots ...

BRIEF DESCRIPTION OF THE FIGURES Other advantages, objects and features of the present invention will become apparent from the description which follows, given for explanatory and non-limiting purposes, with reference to the appended drawings, in which:

FIG. 1 represents the steps of the method according to the invention according to a first embodiment,

FIG. 2 represents all the steps of the method according to another embodiment,

FIG. 3 represents a similar view of the process according to the invention, showing the recycling cycle of the water 26 of the tanks.

DESCRIPTION OF EXAMPLES OF EMBODIMENT OF THE INVENTION

Figure 1 shows the steps of a process for valuing cigarette butts.

The method uses cigarette butts 40, composed of a filter 41 and organic material 32. The organic material 32 is composed of ash, paper sheets and tobacco. The filter 41 is composed of cellulose acetate 33 and paper 34.

The method comprises a step of first grinding 22 from cigarette butts 40 which consists of passing through a first mill cigarette butts 40 in continuous flow. The first mill chisels cigarette butts 40 at a rate of 1kg of cigarette butts per minute. The first mill separates the filter 41 from the organic material 32. At the outlet of the first milling 22, there is the organic material 32 separated from the filter 41.

After the first grinding step 22, the method comprises a sieving step 23. The sieving step 23 comprises a sieve in which the filter 41 and the organic material 32 are sent. The sieving step 23 consists of the separation the filter 41 of the organic material 32, to recover only the filter 41. The sieve used in the sieving step 23 operates using a vibrator motor that vibrates the sieve until the filters 41 are completely separated from the organic material 32. This sieving system 23 causes the separation of the various arrivals of filters 41 and organic material 32 by separating progressively, the organic material 32 and the filter 41 by a gradient of three levels. In an exemplary embodiment, the speed is 1kg per minute. Organic matter 32 is retained at this stage of the process. The organic material 32 is stored to be partially subsequently decolluted in a water bath, not shown.

After the sieving step 23, the method comprises a step of washing the filter 24.

In an alternative, steps 22 and 23 are performed together. The washing step 24 of the filter 41 separates the paper 34 from the cellulose acetate 33 in a washing tub. The washing tub has a purpose of cleaning the filters 41. In an exemplary embodiment, the solvent used in the wash tub is water. In another embodiment, acetone is used as a solvent. The separation is based on the density of the paper 34 and cellulose acetate 33 present in the wash tub. The duration is at least twenty minutes, preferably thirty minutes. In fact, the paper 41 and the cellulose acetate 33 do not have the same density, the paper 41 has a higher density than the cellulose acetate 33, the paper 41 is therefore found at the bottom of the tank and the acetate Cellulose 33 is found on the surface of the wash tub. The papers 41 are removed from the wash tub and directed to the not shown recycling die. The product resulting from this step is cellulose acetate 33.

After the washing step 24 of the filter 41, the method comprises a decollution washing step 25 of the cellulose acetate 33. The decontamination washing step 25 depollutes in a decontamination tank the cellulose acetate 33 of the substances harmful pollutants. The solvent used in the decontamination tank is water. In another embodiment, acetone or any other type of solvent is used to remove harmful substances. This cleaning uses the closed flow technique to significantly clean the cellulose acetate 33, the amounts of polluting harmful substances decrease drastically and because some residues such as nicotine present in the cellulose acetate 33 dissolve in the water. 'water. The cellulose acetate 33 remains at least twenty minutes in the decontamination tank, preferably thirty minutes. The product of the depollution wash step 25 is depolluted cellulose acetate 37.

In an exemplary embodiment, the pollution control tank is used several times. The depollution operation in the pollution control tank is repeated three times. Repetition improves the quality and cleanliness of the final product, as some pollutants such as tar require another type of solvent.

In another embodiment, there are several depollution tanks as described below, FIG.

The product resulting from the scrubbing wash step 25 is of the cleaned cellulose acetate 37.

After the decontamination washing step 25, the method comprises a step of recycling the water 26 of the decontamination tank. The step of recycling the water 26 of the decontamination tank in a dirty water rebreather has a system operating on chemical and physical clariflulation processes applied to the water to treat and purify it. Clarifloculation treatment is based on a first so-called coagulation phase corresponding to a destabilization of the colloidal substances present (suspended substance that does not diffuse through a semi-permeable membrane) and a second so-called flocculation phase with particle agglomeration. in the form of micro-flakes and flakes gradually enlarging until a clear separation is obtained called decantation, not shown. The chemical reaction takes place inside a tank, not shown. In one example, the tank is plastic. In an exemplary embodiment, the dosing of the chemicals as well as the completion of the flocculation and settling processes take place in the tank, completely automatically. The water rebreather 26 is capable of treating up to 1000 liters of water per cycle, each cycle lasts about two hours. The energy cost of this recycling is low because the water rebreather 26 uses only one kilowatt per hour knowing that the duration of a cycle is about two hours, only two kilowatts are necessary. The water thus recycled is then stored in a recycled water tank 36 before being sent back to the washing tub and the decontamination tank.

After the scrubbing washing step 25, the method comprises a pre-cooking drying step 27. The pre-cooking drying step 27 is performed from the cleaned cellulose acetate 37 resulting from the step 25. The pre-cooking drying step 27 is carried out in a pre-cooking oven to obtain dried cellulose acetate 38. The pre-cooking drying step 27 is carried out at least at 100 ° C. preferably 120 ° C. The pre-cooking drying step is complete when the water vapor is no longer present at the air outlet.

After the pre-cooking drying step 27, the method comprises a second milling step 28. The second milling stage 28 from the dried cellulose acetate 38 is carried out to obtain fine fibrous particles of cellulose 39. The second grinding step 28 ends when the dried cellulose acetate 38 is shredded into fine particles. The term "fine particles" means particles with a diameter of less than 1500 μm, but preferably close to 1000 μm.

Figure 2 shows another process for valuing cigarette butts.

Steps 22, 23, 24, 25, 26, 27 and 28 correspond to the description above. The step of collecting and storing cigarette butts 40 is done, for example, in companies, in communities. The collection must be selective, that is to say that the cigarette butts must be collected in a container recovering only these in order to facilitate the recovery and treatment. Once collected, the cigarette butts are routed to the recovery site for storage. The sorting step 21 is carried out manually and makes it possible to eliminate unwanted waste destined for recycling 31 such as chewing gum, matches, aluminum from cigarette packs or any other object other than cigarette butts. At the end of the sorting step 21, only cigarette butts are obtained. The thermo-compression step 29 of the fine fibrous particles of cellulose acetate 39 in a thermo-compression press. The thermo compression press is used for the purpose of melting the fibrous fine cellulose particles 39 and making them cellulose acetate plates 30 of the desired thickness depending on the cuts and objects to be manufactured. The thermo-compression press combines a heating station and a cooling station. In one example, the thermo compression press has the following characteristics: power 314 tons, work surface 80x60cm, heating 350 ° C. The production of cellulose acetate plates 30 of precise thickness is possible because of its mechanical stops incorporated in the two hydraulic pressure cylinders.

Figure 3 shows a realization of the recycling of water 26 integrated in the process of upgrading cigarette butts. Step 29 corresponds to the description above. The decontamination washing step 25 in three depollution tanks depollutes the cellulose acetate 33 polluting harmful substances that are embedded in the combustion of tobacco. The solvent used in the depollution tanks is water.

The passage from one pollution control tank to the other is done using a pump. The depollution operation in the three depollution tanks is repeated three times. Repetition improves the quality and cleanliness of the final product.

NOMENCLATURE 20 Collection and storage 21 Sorting 22 First grinding 23 Sieving 24 Washing the filter 25 Pollution washing 26 Water recycling 27 Pre-cooking drying 28 Second grinding 29 Thermo-compression 30 Cellulose acetate plates 31 Miscellaneous waste 32 Material organic: ash, sheet of paper and tobacco 33 Cellulose acetate 34 Paper 36 Recycled water tank 37 Cleaned cellulose acetate 38 Dried cellulose acetate 39 Fine cellulose fiber particles 40 Cigarette butts 41 Filter

Claims (8)

A method of upgrading cigarette butts (40), comprising a filter (41) and organic material (32) composed of ash, paper sheets and tobacco, said filter (41) being composed of acetate of cellulose (33) and paper (34), characterized in that the method comprises the following steps of: - a) first grinding (22) from cigarette butts (40) in a first mill to separate the filter ( 41) organic matter (32); - b) sieving (23) of the filter (41) and the organic material (32) from the first grinding stage (22) to recover the cellulose acetate (33) contained in the filter; - c) washing (24) of the filter (41) for separating the cellulose acetate (33) and the paper (34) from the sieving (23) with water in a washing tank; d) decontamination washing (25) of the cellulose acetate (33) with water in a decontamination tank to obtain cleaned cellulose acetate (37); e) recycling the water (26) of steps c) and d) by a water recycler; f) pre-cooking drying (27) from the cleaned cellulose acetate (37) to obtain dried cellulose acetate (38); - g) second milling (28) from the dried cellulose acetate (38) to obtain fibrous fine particles of cellulose acetate (39). 2. The method of claim 1, wherein step d) comprises two other decontamination tanks for cleaning the cellulose acetate (33), the cellulose acetate (33) passes from a decontamination tank to the other. The method of claim 1, wherein step d) is repeated three times. 4. The method of claim 1, wherein the washing (24) of the filter (41) of step c) and the scrubbing wash (25) of step d) is done with a solvent, preferably the water. 5. The method of claim 1, wherein the recycling of water (26) of step e) is carried out in a closed circuit. 6. The method of claim 1, wherein the water rebreather of step e) comprises a coagulation step and a flocculation step. 7. The method of claim 1, wherein the method comprises a step h) of thermo compression (29) in a thermo compression press. 8. Process according to claim 1 for the manufacture of cellulose acetate plates (30) based on fine fibrous particles of cellulose acetate (33).