Method for producing collection devices based on recycled rubber

Abstract

The present application relates to a method for producing collection devices based on recycled rubber, which comprises five steps: kneading; mixing; moulding; drying and resting. The method results in a material composed of a mixture of polymers derived from end-of-life tyres (EOLTs) and thermoplastic waste derived from expanded or extruded polystyrene (E / X-PS), in addition to an organic solvent. The method, based on recycled rubber from EOLTs and thermoplastic waste derived from E / X-PS, provides a series of advantages: ability of the material to repel moisture; a lower weight with respect to other devices made using other materials; lower energy use in the production thereof; and compliance with circular economy guidelines, which contributes to caring for the environment.

Description

[0001] MANUFACTURING PROCEDURE FOR COLLECTION DEVICES BASED ON RECYCLED RUBBER

[0002] FIELD OF INVENTION

[0003] This innovation relates to a manufacturing process for Collection Devices (CD) using recycled rubber from End-of-Life Tires (ELTs) as the main component. This innovation primarily seeks to transform ELTs into products useful for various productive sectors, while also contributing to reducing environmental pollution caused by waste derived from ELTs and thermoplastics derived from E / X-PS.

[0004] BACKGROUND OF THE INVENTION

[0005] Citing Chile as an example, the agricultural and manufacturing sectors contribute significantly to the national GDP (approximately 15% of the Gross Domestic Product according to figures from the Office of Agrarian Studies and Policies and the Central Bank of Chile). In these sectors, the use of Collection Devices (CDs) such as bins, harvest boxes, containers, pallets, drums, composters, among others, is the primary way to collect, transport, and handle agricultural, manufactured, and industrial products. These devices are produced from wood, and for reasons of certification, hygiene, and durability, some devices are also made from plastic or metal. The importance of plastic CDs translates into annual revenues of more than $165 million. This precedent is proportionately and generally replicated worldwide.

[0006] However, even though the current state of the art regarding materials for the manufacture of various elements is broad and considers a series of new inputs that aim to comply with the principles that support the Economy

[0007] 1

[0008] SUBSTITUTE SHEET (RULE 26) Circular, the advances made in these devices continue to use, mainly, new plastic and, to a lesser extent, recycled plastic.

[0009] Today, concepts such as the Circular Economy, recycling, upcycling, and carbon footprint reduction are common and transversal terms across various sectors. Various reports show that carbon footprint reduction is a necessity in all markets, including agriculture and manufacturing. This has resulted in many countries, for example, European countries, increasingly requiring environmental certifications (ISO 14000 Series, BRC of Great Britain) and products with a lower carbon footprint. This opens up an opportunity to generate products and services that contribute to the environmental sustainability of production processes in the broad agricultural products market.

[0010] On the other hand, following Chile's example, a government-level process began in 2019 and is currently underway: the Circular Economy Roadmap. Its vision is "that, by 2040, the regenerative circular economy will drive Chile toward sustainable, fair, and participatory development that puts people's well-being at its center; this will be achieved through caring for nature and its living beings, the responsible and efficient management of natural resources, and a society that uses, consumes, and produces sustainably and consciously, fostering the creation of green jobs and opportunities for people and organizations throughout the country." This roadmap, consequently, opens up a significant opportunity for all science- and technology-based ventures that design new products, for example, using waste as manufacturing inputs, thereby complying with the principles of the circular economy.Considering the inadequate waste management in Chile, the Extended Producer Responsibility and Recycling Promotion Law, known as the EPR Law, was enacted in 2016. It seeks to reduce and reclaim six priority waste products, including: lubricating oils, electrical appliances, batteries, containers and packaging, and tires. According to data from the Ministry of the Environment, approximately 6.6 million tires are discarded in Chile, and only 17% are managed in an environmentally sound manner. This, therefore, translated into recovery and reclaiming goals established in the decrees derived from the EPR Law, which stipulate that by 2023, 25% of the NFU entering the market must be reclaimed, reaching a 90% reclaimed value by 2030.This law, like the Circular Economy Roadmap, opened up the opportunity to generate new products through innovations in waste, particularly waste tires.

[0011] Currently, there are several technologies available that address the technical field of waste treatment and resource utilization through recycling and revalorization of non-liquid waste. For example, publication W02017157180A1 proposes a non-liquid waste treatment technology, specifically a tire rubber cracking method. The aforementioned publication provides a method for the pyrolysis of tire rubber, which, through a series of stages, produces a liquid hydrocarbon mixture. This method contributes to effectively reducing energy consumption and pyrolysis time, and saves costs.

[0012] In addition to the previous publication, there is patent EP2794766B1, which refers to a method for recycling rubber waste. This method includes, among its steps, the pyrolysis of rubber to obtain a carbonized material, which is subsequently ground. This patent also refers to the products obtained, such as carbon black powder and granulated carbon black, and in particular, to the use of said products.

[0013] On the other hand, publication US11753530B2 proposes a method in which crumb rubber obtained from recycled tires undergoes an interconnected replacement process. This process uses a reactive component that interferes with sulfur bonds, resulting in the treated rubber having properties similar to those of the virgin compound rubber structure before granulation. The publication shows that this product is suitable for use in the manufacture of new tires, engineered rubber articles, and asphalt rubber for use in waterproofing and paving applications.

[0014] In addition to the aforementioned publications, there is patent US91 14580B2, which proposes an invention aimed at producing manufactured articles that have at least one part made from recycled material, including, among others, recycled rubber or other polymeric materials. The proposed invention also provides methods for preparing articles formed from granulated materials, such as, for example, a shoe, which can have all or part of it manufactured using the granulated material. To bond these granules together, it is proposed to use a binder material such as a polyurethane, preferably a single-component, moisture-curing polyurethane binder. The proposed inventive methods are characterized by their economic benefits, ease of use, and environmental benefits.

[0015] The state of the art shows that there are inventions that propose the manufacture of products using rubber as one of the inputs. However, in many of these innovations, the intensive use of energy to reach high temperatures in multiple processes, for example, pyrolysis, is a disadvantage due to the economic and environmental costs involved. Another distinguishing feature compared to the existing state of the art is that the present proposal does not use binders or adhesives, but rather uses a mixture based on thermoplastics with organic solvents.

[0016] Finally, the state of the art shows that items belonging to the Collection Devices category are primarily made from plastic materials, including HDPE or PET. And while devices have begun to be manufactured using recycled plastics, the amount of this used in new items is lower, unlike the proposal presented here. In this sense, the items produced using this innovation are made from 100% recycled waste, both from recycled plastics and thermoplastics.

[0017] PURPOSE OF THE INVENTION

[0018] The objective of the invention is to develop collection devices made from a mixture containing, primarily, recycled rubber from end-of-life tires and other components such as thermoplastic waste derived from expanded or extruded polystyrene. All this is achieved through a high-performance process that contributes to overcoming the disadvantages of current rubber recycling and recovery technology, that is, by reducing intensive energy use and increasing the proportion of recycled waste used in the production of the devices.

[0019] Thus, the objective of the invention is not only to propose a new method for making devices that are widely used in multiple sectors, for example, agricultural, manufacturing and industrial, but also to significantly contribute to reducing the amount of waste (NFU and thermoplastics derived from E / X-PS) that at the end of their useful life end up polluting the environment or ending up in landfills without generating added value.

[0020] ADVANTAGES OF INNOVATION SUBJECT OF THIS APPLICATION

[0021] The material made from recycled NFU rubber and E / X-PS-derived thermoplastic waste has multiple potential uses, including the manufacture of collection devices such as: Bins; Storage baskets; Pallets; Composters; Harvesting mats, among others. Each of these collection devices is widely and intensively used in various sectors, including agriculture, manufacturing, industry, and residential. These collection devices made from recycled NFU rubber and E / X-PS-derived thermoplastic waste have several advantages over other products currently on the market.Among these advantages is the material's ability to repel moisture, which, compared to other wooden items such as bins, pallets, or storage baskets, prevents the storage device from gaining extra weight or deteriorating due to the intense action of water. This ability to repel water consequently makes the storage devices lighter than wood products that absorb moisture from the environment, increasing their weight.

[0022] Furthermore, the chemical and physical characteristics of the material made from recycled rubber from non-recycled materials and thermoplastic waste derived from E / X-PS mean that the collection devices produced use little energy. This, compared to other products on the market made from plastic, represents an advantage, as the reduction in energy costs can translate into lower prices for future customers and a lower carbon footprint.

[0023] Along with the above, it is important to mention that the Collection Devices designed and manufactured comply with the guidelines of the Circular Economy. This, considering that the process for preparing the mixture and the Devices themselves, allows the inputs to be reintegrated into the production cycle even when the useful life of the Devices has ended. This allows the inputs, which had originally been waste, to be maintained for a longer time within the production cycles without being finally disposed of as waste that ends up in a landfill with no added value. This advantage is significant since many of the current Collection Devices available on the market do not comply with the guidelines of the Circular Economy, thereby generating waste that is not reintegrated into the production cycle once the useful life of the items has ended. DETAILED DESCRIPTION OF THE INVENTION

[0024] General procedure for manufacturing storage devices.

[0025] For the production of Collection Devices, it has been proposed to design and implement a “Standardized and optimized Collection Device manufacturing procedure through the use of recycled rubber from NFU and thermoplastic waste derived from E / X-PS”.

[0026] To determine and characterize the physical properties of the base material used in the manufacture of the Storage Devices, a series of tests were performed, defined based on the type of functions that the DAs would perform in the different sectors. Consequently, the tests performed corresponded to those that allowed determining the tensile strength and percentage of elongation of the material, as well as its impact resistance. These tests were carried out using protocols established in ASTM D638-14: "Standard Test Method for Tensile of Plastic" and ASTM E2486 / E2486M-13: "Standard Test Method for Impact Resistance of Class PB and PI Exterior Insulation and Finish Systems (EIFS)".With these tests, it was possible to determine the proportions of inputs needed to prepare the mixture needed for each of the devices.

[0027] In addition to the tests to evaluate impact and tensile strength, the multiple functionalities of the Collection Devices require considering other relevant properties that the material with which the devices are manufactured may have. In this sense, the base material used in the manufacture of the Collection Devices was subjected to water containment tests, which is subsequently subjected to moisture content tests, adapted from the AOAC 925.45 standard; AOAC 925.10; AOAC 927.05; AOAC 926.08 AOAC 934.06: This, in order to determine the material's ability to absorb or repel water after the devices are manufactured. Along with the above, the ash content of the material was also evaluated, through tests adapted from the AOAC 923.03 standard; AOAC 930.22; AOAC 920.181; AOAC 935.42; AOAC 940.26; AOAC 940.26; AOAC 945.46; AOAC 930.30.This allows us to establish, in general terms, the percentage of inorganic compounds present that could be released during the use of the collection devices. Both tests are performed in analytical laboratories accredited under the ISO / IEC 17025 / 2017 standard.

[0028] Based on the physical properties of the mixtures and their different proportions of inputs, it was possible to design and implement the steps required to create the Storage Devices. These steps are: Kneading; Mixing; Forming; Drying; and Resting.

[0029] Kneading: The kneading stage corresponds to the one in which the inputs are arranged in the specific proportions to develop a mixture that has the adequate flexibility and resistance properties for the required Collection Device. In this stage, the inputs of NFU, Thermoplastics and chemical solvents are kneaded and then incorporated into the mixing system. In this sense, it is necessary to establish that the components that form part of the material are: Thermoplastic Waste (E / X-PS), organic solvents and End-of-Life Tires (END-Tyres). The latter can be used in its different forms, that is, depending on the size it has: Large (Size greater than 1.2 mm); Small (Size between 0.8 and 1.2 mm) and Rubber Powder (Size less than 0.8 mm). Regarding the manufacturing of the Collection Devices,The total proportion of rubber that the device will have can range from 55% to 65% of the total final weight of the Device. As for the thermoplastic waste (E / X-PS), this can range from 35% to 45% of the total final weight of the Device and as for the organic solvent, this can be incorporated into the mixture in an amount between 30% and 35% of the total initial weight of the mixture that makes up the Device. It should be noted that among the organic solvents that can be used in this invention are: propanone, 2-butanone, 2-pentanone, 3-pentanone, 2-hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4-hectanone, 2-octanone, 3-octanone, 4-octanone, 2-nonanone, 3-nonanone, 4-nonanone, 5-nonanone, 2-decanone, 3-decanone, 4-decanone, 5-decanone, 2-undecanone, 3-undecanone, 4-undecanone, 5-undecanone, 6-undecanone, 2,4-pentadione, 2,5-hexanedione, 2,4-heptanedione, 2,5-heptanedione, 2,6-heptanedione, 3,5-heptanedione, 3,6-heptanedione, methyl ethanoate, ethyl ethanoate,propyl ethanoate, isopropyl ethanoate, butyl ethanoate, isobutyl ethanoate, secbutyl ethanoate, tertbutyl ethanoate, pentyl ethanoate, methylbutyl ethanoate, 2-methylbutyl ethanoate, 3-methylbutyl ethanoate, 1,2-dimethyl propyl ethanoate, 2-ethylpropyl ethanoate, hexyl ethanoate, methylpentyl ethanoate, 2-methylpentyl ethanoate, 3-methylpentyl ethanoate, 4-methylpentyl ethanoate, ethylbutyl ethanoate, 2-ethylbutyl ethanoate, 3-ethylbutyl ethanoate, methyl propanoate, ethyl propanoate, propyl propanoate, isopropyl propanoate, butyl propanoate, isobutyl propanoate, secbutyl propanoate, tertbutyl propanoate, pentyl propanoate, methylbutyl propanoate,

[0030] 2-methylbutyl propanoato, 3-methylbutyl propanoato, 1 ,2-dimethylpropylpropanoato, 2- ethylpropyl propanoato, hexyl propanoato, methylpentyl propanoato, 2-methylpentyl propanoato, 3-methylpentyl propanoato, 4-methylpentyl propanoato, ethylbutyl propanoato, 2-ethylbutyl propanoato, 3-ethylbutyl propanoato, pentano, 2-methylpentano,

[0031] 3-methylpentane, hexane, 2-methylhexane, 3-methylhexane, heptane, 2-methylheptane,

[0032] 3-methylheptane, 4-methyl heptane, octane, 2-methyloctane, 3-methyloctane, 4- methyloctane, nonane, 2-methyl nonane, 3-methylnonane, 4-methylnonane, 5- methylnonane, decane, 2-methyl decane, 3-methyldecane, 4-methyldecane, 5- methyldecane, 2-ethyl pentane, 3-ethyl pentane, 2-ethylhexane, 3-ethylhexane, 2- ethylheptane, 3-ethyl heptane, 4-ethyl heptane, 2-ethyloctane, 3-ethyloctane, 4-ethyloctane, 2- ethylnonane, 3-ethyl nonane, 4-ethyl nonane, 5- ethyl nonane, 2-ethyldecane, 3-ethyldecane,

[0033] 4-ethyldecane, 5-ethyldecane, benzene, toluene, xylene, thmethylbenzene, ethylbenzene, diethylbenzene, propyl benzene, dipropylbenzene, chloroform, dichloromethane, gasoline, kerosene, carbon tetrachloride, among others, and their mixtures. Mixing: The mixing stage is the continuation of the process, after the kneading stage. During mixing, all the inputs are integrated to achieve a mixture that allows obtaining a Collection Device with specific characteristics of tensile and impact resistance. In this stage, first (a), in a container, the organic solvent is mixed with the thermoplastic waste derived from E / X-PS until reaching a concentration between 35% and 45% w / w. This mixture is stirred until the thermoplastic waste derived from E / X-PS is completely dissolved in the organic solvent.After this (b), the recycled rubber is incorporated in its different forms (according to the granule size), adding, first, the largest rubber and ending with the smallest rubber. The incorporation of the different recycled rubber granules is done slowly so that the initial mixture (thermoplastic plus organic solvent) can completely impregnate the recycled rubber granules. Once the different types of rubber (according to granule size) have been incorporated, they must be beaten during the complete mixing for at least 10 minutes to achieve an adequate consistency and homogeneity of the mixture.

[0034] Molding: When the mixture has fully incorporated all the components, it must move on to the molding stage. In this case, a pressing molding system is used, which corresponds to the method by which the prepared mixture is poured into an outer mold which is closed with another inner counter mold inside the first, to this system Outer mold - Mixture - Inner counter mold to which pressure is applied to achieve the structure of the Collection Device. Prior to pouring the mixture (a) onto the molds for molding, the molds must be impregnated with release agents (organic or inorganic, depending on the mold material) in order to release the article from the mold once the process is completed.Having incorporated the release agent film into the moulds, (b) the prepared mixture is poured into the outer mould, and then a second, smaller mould (inner counter mould) is placed on top of this outer mould - Mixture system, which is designed to give shape to the Collection Devices, (c) The outer mould - Mixture - inner counter mould system is placed inside the compression equipment which compresses the system until it reaches the required arrangement that allows obtaining the Collection Device.

[0035] Drying: After the compression procedure of the Outer Mold - Mix - Inner Counter Mold system, it is removed from the compression equipment and placed inside the drying chamber. This corresponds to a chamber in which the molds with their respective mixtures are introduced and a drying process of the mixture is carried out. The drying procedure consists, first (a), in setting the temperature increase so that it progresses from room temperature to 50 ° C gradually. The time required to reach the final temperature of 50 ° C is at least 45 to 60 minutes, depending on the Collection Device manufactured, (b) Once the final temperature (50 ° C) is reached, the Outer Mold - Mix - Inner Counter Mold system is removed from the drying chamber in order to extract the Outer Mold, leaving the mixture and its shape arranged in the Inner Counter Mold.This, with the objective of having a larger surface of the mix to the environment so that the drying speed increases, (c) Finally, the inner Countermold with the mix is ​​placed again inside the drying chamber, this time, in such a way that each of the faces of the mix with the structure of the Collection Device are exposed. Once inside the drying chamber, the inner Countermold - Mix system must be, again, at least 45 to 60 minutes depending on the Collection Device that is being manufactured.

[0036] Resting: Finally, after the drying stage, to achieve the final structure of the Collection Devices, each of these must go through a Resting stage. This consists of the final "curing" of the product until achieving the optimal tensile and impact resistance depending on the Device manufactured. Having removed the Inner Counter Mold - Mix system from the drying chamber, the Outer Mold that had been removed in stage b) of the drying phase is reinserted. Consequently, the Outer Mold - Mix - Inner Counter Mold system is placed in a chamber at room temperature to complete drying and its corresponding curing for at least 12 hours. After this time, the Inner Counter Mold is removed, leaving the Outer Mold - Mix system drying for at least 12 more hours. Finally, the mold is removed, leaving the mix with the structure of the corresponding Collection Device.

Claims

CLAIMS 1. Manufacturing process for Collection Devices based on Recycled Rubber that results in a material composed of a mixture of polymers derived from end-of-life tires and thermoplastic waste, specifically, expanded or extruded polystyrene, in addition to an organic solvent CHARACTERIZED by being composed of five stages, these being: kneading, mixing, molding, drying and resting, in which, mainly, recycled rubber from end-of-life tires is used, in addition to other inputs, in the following proportions: a) Recycled Rubber from End-of-Life Tires: 4% to 40% of the total weight of the initial mixture to manufacture the Device, b) Expanded or extruded Polystyrene Waste: 20% to 30% of the total weight of the initial mixture to manufacture the Device, c) An organic solvent: 30% to 35% of the total weight of the initial mixture to manufacture the Device.

2. Manufacturing process for Collection Devices according to claim 1, CHARACTERIZED in that the main component of the mixture for manufacturing Collection Devices corresponds to recycled rubber from end-of-life tires with different granulometries ranging from a size less than 0.8 mm to an approximate size of 1.5 mm.

3. Manufacturing process for Collection Devices according to claim 1, CHARACTERIZED in that the secondary component of the mixture for manufacturing Collection Devices corresponds to thermoplastic waste derived from expanded or extruded polystyrene (E / X-PS) with densities that can range from 10 kg / m 3 at 40 kg / m 3 .

4. Manufacturing process for Collection Devices according to claim 1, CHARACTERIZED in that the organic solvent used in The manufacturing process for Storage Devices is preferably chosen from among the following solvents: acetone; xylene; ethyl acetate and toluene.

5. Manufacturing process for Collection Devices according to claim 1, CHARACTERIZED in that the following quantities of each input are incorporated in the first kneading stage, depending on the Collection Device being manufactured: Regarding recycled rubber from end-of-life tires, between 1 and 35 kg are required; of thermoplastic waste derived from expanded or extruded polystyrene (E / X-PS), between 0.5 and 20 kg are required; finally, of the chosen organic solvent, in particular, acetone, between 1 and 35 L are required.

6. Manufacturing process for Collection Devices according to claims 1 and 5, CHARACTERIZED in that in the second mixing stage the proportions previously described are incorporated according to the Collection Device to be manufactured, in the following order: a) The defined quantity of thermoplastic waste derived from expanded or extruded polystyrene (according to the Device to be Manufactured) is incorporated with the defined solvent and kneaded, stirring at a speed between 50 and 250 RPM, until the thermoplastic waste (E / X-PS) is completely dissolved in the organic solvent, reaching an approximate concentration between 35% and 45% w / w. b) The recycled rubber, massed according to the type of Collection Device specified in claim 5, is incorporated into the mixture made in 6.a), adding, first, the recycled rubber of larger size and ending with the rubber of smaller size slowly and stirring the mixture at a speed between 200 and 500 RPM.c) When all the recycled rubber in its different granulometries has been incorporated into the mixture, it must be stirred for at least 10 minutes to achieve adequate consistency and homogeneity of the mixture.

7. Manufacturing process for Storage Devices according to claim 1, CHARACTERIZED in that in the third stage, using the press molding technique, the following process is carried out: a) the mixture obtained according to claim 6 inside an outer mold; b) another counter mold is inserted into the mixture inside the first outer mold; c) this Outer Mold - Mixture - Inner Counter Mold system is placed inside the compression equipment which exerts a pressure of between 1 and 10 metric tons in order to generate the structure of the required Storage Device.

8. Manufacturing process for Collection Devices according to claim 1, CHARACTERIZED in that in the fourth stage the Outer Mold - Mixture - Inner Counter Mold system that has been compressed as indicated in claim 7 is introduced into a drying chamber. In this chamber the process that is executed consists of (a) progressively increasing the temperature from room temperature to 50°C, which will require a time ranging from 45 to 60 minutes, depending on the Collection Device manufactured; (b) Once the final temperature (50°C) has been reached, the Outer Mold - Mixture - Inner Counter Mold system is removed from the drying chamber and the Outer Mold is separated from the Mixture, leaving the latter in its Collection Device shape supported on the inner Counter Mold;(c) Finally, the Inner Counter Mold with the Mixture is reintroduced into the drying chamber, this time inverted, that is, leaving each of the faces of the Mixture with the structure of the Collection Device exposed towards the drying chamber; (d) Once inside the drying chamber, the Inner Counter Mold - Mixture system must be, again, between 45 to 60 minutes depending on the Collection Device being manufactured.; 9. Manufacturing process for Storage Devices according to claim 1, CHARACTERIZED in that in the final stage the Inner Countermold - Mixture system obtained, according to claim 8, is extracted and reintroduced into the Outer Mold, leaving, once again, the system as Outer Mold - Mixture - Inner Countermold. This system is introduced into a chamber at room temperature to achieve drying and its corresponding curing during, 10 to 13 hours, depending on the Storage Device being manufactured. After this time, the inner countermold is removed, leaving the outer mold-mixture system to dry again for another 10 to 13 hours. Finally, once this time has elapsed, the outer mold is removed, leaving the mixture with its corresponding Storage Device structure.

10. Manufacturing process for collection devices according to claims 1 to 9, characterized in that it can be applied to the manufacturing of devices such as: open bins without lids; closed bins without lids; open bins with lids; closed bins with lids; harvest boxes of various sizes; composters; vermicomposters; unpadded baskets; padded baskets; closed pallets; reversible pallets; 2- and 4-entry pallets; Euro pallets; American pallets.