FR3066128A1 - METHOD FOR ENHANCING CIGARETTE MEGOTS - Google Patents

Abstract

The invention relates to a process for the recovery of cigarette butts (40), composed of a filter (41) and organic material (32) composed of ash, sheets of paper and tobacco, said filter (41) being composed of 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 for recovering 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 material or organic waste is transformed for the purpose of a specific use such as recycling, in order to ultimately generate income. Cellulose acetate is a plastic material and comes in the form of fibers.

Collection areas are installed in businesses, public places, streets, beaches, ski resorts, campsites ...

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

STATE OF THE ART

The recovery process is suitable for recycling the cigarette butt remaining after use. The cigarette butt consists of a filter, including cellulose acetate and a paper envelope. The filters making up the cigarette butt absorb more than four thousand harmful chemicals which have an irritant, harmful, toxic, mutagenic and carcinogenic action in the surrounding environment as they enter the respiratory system of the smoker.

For the reasons presented above, each cigarette is therefore provided with a filter at one of its ends making it possible to retain a portion of the abovementioned harmful chemicals. When the cigarette is consumed, the filter is therefore placed so that the smoke passes through the filter before reaching the smoker's lungs.

Consequently, part of these harmful substances is therefore trapped in the filter and contaminates the part of smokeless cigarette, otherwise called 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 filter is done.

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

Cigarette butts are considered environmentally hazardous waste, they represent 40% of the waste present in the Mediterranean Sea. Birds and sea animals die from the direct ingestion of cigarette butts.

Certain methods of treating cigarette butts exist and make it possible to obtain a product based on plastic and on a percentage of cigarette butts and plastic. However, there are traces of toxic residues in cigarette butts and therefore the product from this type of process.

One of the objectives of the invention is to provide a process allowing the recycling of 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 process that is simple to implement while respecting ecological constraints.

OBJECT OF THE INVENTION

The present invention aims to remedy these drawbacks. To this end, the present invention relates to a process for recovering cigarette butts, composed of a filter and of organic material composed of ashes, sheets of paper and tobacco, said filter being composed of cellulose acetate and of paper, characterized in that the method comprises the following steps of: - a) first grinding from cigarette butts in a first grinder to separate the filter from the organic matter; - b) sieving of the filter and of the organic matter, originating from the first grinding stage to recover the cellulose acetate contained in the filter; - c) washing the filter for separation of the cellulose acetate and the paper after sieving with water, in a washing tank; - d) depollution washing of cellulose acetate with water in a depollution tank to obtain depolluted cellulose acetate; - e) recycling of water from steps c) and d) by a water recycler; - f) drying by pre-cooking from decontaminated cellulose acetate to obtain dried cellulose acetate; - g) second grinding from dried cellulose acetate to obtain fine fibrous particles of cellulose acetate.

The process for upgrading cigarette butts makes it possible to produce fine, fibrous particles of cellulose acetate, which are depolluted and can be used for the manufacture of various objects.

Thanks to these provisions, the sieving step allows the gradual separation of the waste. Tobacco, ash, sheets of paper and filter are separated as you go, making it easier and simpler to recover cellulose acetate.

The filter washing step separates the cellulose acetate from the paper, allowing only the cellulose acetate to be recovered.

Washing in the pollution control tank removes harmful pollutants retained by cellulose acetate. Analysis of the water contained in the washing tank and the pollution control tank shows a decrease in the quantities of harmful polluting substances. Recycling water makes it possible to have water already used without harmful substances. The invention is advantageously implemented according to the embodiments and the variants set out below, which are to be considered individually or according to any technically effective combination.

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

In one embodiment, step d) is repeated three times. The triple repetition of washing in the three pollution control 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 depollution washing of step d) is carried out with a solvent, preferably water.

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

In one embodiment, the water recycler, from step e) comprises a coagulation step and a flocculation step. The water recycler treats up to 1000 liters per cycle in order to recycle the water from the washing and depollution tanks. The water recycler allows the regeneration of water by locative clarification.

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 handling pallets and / or urban furniture. Many objects can thus be created from the plastic plates obtained such as coasters, parquet, furniture, advertising media, outdoor ashtrays and flower pots ...

BRIEF DESCRIPTION OF THE FIGURES Other advantages, aims and characteristics of the present invention will emerge from the description which follows, given for explanatory purposes and in no way limiting, 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 of the steps of the method according to another embodiment,

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

DESCRIPTION OF EXAMPLES OF EMBODIMENT OF THE INVENTION

Figure 1 shows the steps in a process to recover cigarette butts.

The method uses cigarette butts 40, composed of a filter 41 and organic material 32. The organic material 32 is composed of ashes, sheets of paper 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 in passing the cigarette butts 40 in a first mill in continuous flow. The first shredder chisels cigarette butts 40 at a rate of 1 kg of cigarette butts 40 per minute. The first crusher makes it possible to separate the filter 41 from the organic material 32. At the outlet of the first grinding 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 into which the filter 41 and the organic material 32 are sent. The sieving step 23 consists in the separation of 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 vibrating motor which vibrates the sieve until the filters 41 are completely separated from the organic material 32. This sieving system 23 causes the various arrivals of filters 41 and organic material 32 to be separated by progressively separating the organic material 32 and the filter 41 by a gradient of three levels. In an exemplary embodiment, the speed is 1 kg per minute. Organic matter 32 is retained at this stage of the process. The organic material 32 is stored in order to be partially decontaminated subsequently in a water bath, not shown.

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

In a variant, steps 22 and 23 are carried out together. The washing step 24 of the filter 41 separates the paper 34 from the cellulose acetate 33 in a washing tank. The washing tank has the purpose of cleaning the filters 41. In an exemplary embodiment, the solvent used in the washing tank is water. In another exemplary embodiment, acetone is used as solvent. The separation is based on the density of the paper 34 and the cellulose acetate 33 present in the wash tub. The duration is at least twenty minutes, preferably thirty minutes. Indeed, 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 washing tub. The papers 41 are eliminated from the washing tank and directed to the recycling sector, not shown. The product from this step is cellulose acetate 33.

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

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

In another exemplary embodiment, there are several pollution control tanks as described below, FIG. 3.

The product resulting from the depollution washing step 25 is decontaminated cellulose acetate 37.

After the depollution washing step 25, the method comprises a step of recycling the water 26 from the depollution tank. The step of recycling the water 26 from the depollution tank into a dirty water recycler has a system operating on chemical and physical clarification processes applied to the water to treat and purify it. The clariflocculation treatment is based on a first phase known as coagulation corresponding to a destabilization of the colloidal substances present (suspended substance which does not diffuse through a semi-permeable membrane) and a second phase called flocculation with the agglomeration of particles in the form of micro-flakes and flakes gradually magnifying until a clear separation called decantation is obtained, not shown. The chemical reaction takes place inside a tank, not shown. In one example, the tank is made of plastic. In an exemplary embodiment, the dosing of the chemicals as well as the carrying out of the flocculation and decantation processes take place in the tank, completely automatically. The water recycler 26 is capable of treating up to a thousand liters of water per cycle, each cycle lasting approximately two hours. The energy cost of this recycling is low because the water recycler 26 uses only one kilowatt per hour knowing that the duration of a cycle is approximately two hours, only two kilowatt are necessary. The water thus recycled is then stored in a recycled water tank 36 before being sent again to the washing tank and the depollution tank.

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

After the pre-baking drying step 27, the method comprises a second grinding step 28. The second grinding step 28 from dried cellulose acetate 38 is carried out in order to obtain fine fibrous particles of acetate from 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 method of recycling cigarette butts.

Steps 22, 23, 24, 25, 26, 27 and 28 correspond to the description above. The step of collecting and storing 20 cigarette butts 40 is done for example in businesses, with 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 recovery and treatment. Once collected, the cigarette butts are transported to the recovery site for storage. The sorting step 21 is carried out manually and makes it possible to eliminate unwanted waste intended for recycling 31 such as chewing gum, matches, aluminum cigarette packs or any other object other than cigarette butts. At the end of 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 fine fibrous particles of cellulose 39 and making cellulose acetate plates 30 of the desired thickness according to the cuts and the 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 tonnes, working surface of 80x60cm, heating to 350 ° C. Plates of cellulose acetate 30 of precise thickness are possible by virtue of its mechanical stops integrated into the two hydraulic pressure cylinders.

FIG. 3 shows an embodiment of the recycling of the water 26 integrated into the process for upgrading cigarette butts. Step 29 corresponds to the description above. The depollution washing step 25 in three depollution tanks, removes cellulose acetate 33 from harmful polluting substances which are encrusted therein during the combustion of tobacco. The solvent used in the pollution control tanks is water.

The passage from one depollution tank to another 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 Screening 24 Filter washing 25 Pollution cleaning 26 Water recycling 27 Pre-baking drying 28 Second grinding 29 Thermo compression 30 Plates of cellulose acetate 31 Miscellaneous waste 32 Material organic: ash, sheet of paper and tobacco 33 Cellulose acetate 34 Paper 36 Recycled water tank 37 Polluted cellulose acetate 38 Dried cellulose acetate 39 Fine fibrous particles of cellulose acetate 40 Cigarette butts 41 Filter

Claims (8)

1. Method for upgrading cigarette butts (40), composed of a filter (41) and organic material (32) composed of ash, sheets of paper and tobacco, said filter (41) being composed of acetate cellulose (33) and paper (34), characterized in that the process comprises the following steps: - a) first grinding (22) from cigarette butts (40) in a first grinder to separate the filter ( 41) organic matter (32); - b) sieving (23) of the filter (41) and of the organic matter (32), originating from the first grinding step (22) to recover the cellulose acetate (33) contained in the filter; - c) washing (24) of the filter (41) for separation of the cellulose acetate (33) and the paper (34) from the sieving (23) with water, in a washing tank; - d) depollution washing (25) of cellulose acetate (33) with water in a depollution tank to obtain depolluted cellulose acetate (37); - e) recycling of the water (26) from steps c) and d) by a water recycler; - f) drying by pre-cooking (27) from depolluted cellulose acetate (37) to obtain dried cellulose acetate (38); g) second grinding (28) from dried cellulose acetate (38) to obtain fine fibrous particles of cellulose acetate (39). 2. The method of claim 1, wherein step d) comprises two other pollution control tanks for depolluting cellulose acetate (33), cellulose acetate (33) passes from a pollution control tank to the other. 3. 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 depollution washing (25) of step d) is done with a solvent, preferably water. 5. Method according to claim 1, wherein the recycling of the water (26) of step e) is carried out in a closed circuit. 6. The method of claim 1, wherein the water recycler, from 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. The method of claim 1 for the manufacture of cellulose acetate plates (30) based on fine fibrous particles of cellulose acetate (33).