Process for obtaining thermoplastic compound from industrial solid waste, resulting in thermoplastic sheets

Description

/ 8 “PROCESS FOR OBTAINING THERMOPLASTIC COMPOUND FROM INDUSTRIAL SOLID WASTE, RESULTING IN THERMOPLASTIC SHEETS”. TECHNICAL FIELD OF THE INVENTION

[001] This patent application for invention privilege belongs to the field of materials engineering, more specifically to the sector of recycling industrial waste generated in the footwear, textile, industrial and post-consumer industries, which notably, said invention consists of an efficient recycling process, through fusion, involving the use of materials that are difficult to recover due to their mixture with other materials. The raw materials include polyester-laminated EVA, polyester-laminated nylon, polyurethane-based synthetic and polyester-laminated PVC, as well as non-laminated waste, such as polyester fabric, BOPP, polypropylene and polyethylenes. HISTORY OF THE TECHNIQUE

[002] Even in primitive societies, people reused objects and tools made of stone, wood, and bone due to the scarcity of materials. In ancient Greece and Rome, metals such as bronze and iron were frequently melted down and reused, since their extraction and production were expensive and laborious.

[003] During periods of economic crisis and war, the reuse of materials, such as metals and fabrics, became common. Many objects were recycled out of necessity, due to the difficulty of obtaining new resources.

[004] With the increase in mass production, waste began to accumulate in industrial cities. This led to the realization that certain materials, such as paper, glass, and metals, could be reused on a large scale.

[005] In the 20th century, with the World Wars, the scarcity of resources during the conflicts encouraged government campaigns for the collection and recycling of materials, Petition 870250011509, dated 12 / 02 / 2025, page 16 / 23 / 8 such as metals, rubber and paper. Populations were encouraged to donate recyclable materials for the manufacture of weapons and equipment.

[006] With the environmental movement gaining momentum, especially after events such as the celebration of Earth Day (1970), recycling came to be seen as an essential environmental practice. It was during this period that the first selective collection programs and recycling centers began to emerge in countries such as the United States and Europe.

[007] With increased consumption and waste production, recycling has become a global priority to combat problems such as plastic pollution, greenhouse gas emissions, and environmental degradation. Currently, recycling is an integral part of global efforts to promote sustainability and address environmental challenges. It continues to evolve with technological innovations and changes in societal behavior. State of the Art Analysis

[008] The state of the art related to the present invention is based on the recovery of waste with heterogeneous chemical characteristics present in the same material, which still face technical barriers to recycling due to the mixture of various materials with different melting points. Examples of such waste include: footwear industrial waste (ethylene-vinyl acetate “EVA” laminated with polyethylene terephthalate “polyester”; polyamide “Nylon” laminated with polyethylene terephthalate “polyester”; synthetics based on polyvinyl chloride “PVC” and polyurethane “PU” laminated with polyethylene terephthalate “polyester”). Textile industry (polyethylene terephthalate “polyester” fabrics). Industrial waste (biaxially oriented polypropylene “BOPP”, polypropylene raffia and polypropylene PP). Post-consumer waste (high-density polyethylene “HDPE” and low-density polyethylene “LDPE”).

[009] The proposed method consists of processing these different wastes by fusion. The complexity of recycling these materials increases depending on the Petition 870250011509, dated 12 / 02 / 2025, page 17 / 23 / 8 chemical heterogeneity and the varying melting points presented by each polymer, which results in thermal incompatibilities during joint processing. These incompatibilities hinder uniform melting and the obtaining of a quality recycled compound.

[010] Existing technologies that exhibit some similarity generally comprise specific processes aimed at recycling conventional polymers, using methods such as extrusion, injection, and molding. However, the present invention differs from these technologies in several aspects, encompassing not only waste generated by the footwear (such as highly complex recycled laminated waste) and textile industries, but also industrial and post-consumer waste. Furthermore, the proposed production process flow is more robust and efficient, allowing the processing of diverse materials.

[011] Research conducted in specialized databases revealed documents relating to waste recovery processes, such as document no. BR 102018075287-1, which deals with a “PROCESS FOR OBTAINING THERMOPLASTIC COMPOUND FROM SOLID INDUSTRIAL WASTE FROM THE FOOTWEAR INDUSTRY AND PRODUCT OBTAINED”, referring to a process of recycling and reusing solid waste from the footwear industry to obtain a recyclable thermoplastic composite (C) to be used in the production of shoe soles. The proposed process, in addition to using an abundant residue from the footwear industry (1), transforms an environmental liability into an asset, consisting of simple execution steps, such as grinding (E1), micronization (E2) and extrusion (E4) of the mixture (6) obtained, promoting the obtaining of a thermoplastic compound (C) with the technical characteristics necessary to be used in the production of footwear soles.In this sense, the matter described aims to provide a solution to an environmental problem, allowing the recycling and reuse of solid waste from the footwear sector (1), thus enabling compliance with Law No. 12.305 / 2010 in its art. 7, item VI, by stimulating the economic activity of recycling.

[012] The method presented includes grinding, micronization and extrusion steps to create a thermoplastic compound intended for the manufacture of shoe soles by. Petition 870250011509, dated 12 / 02 / 2025, page 18 / 23 / 8 injection. The raw material includes EVA waste and synthetic fabrics, mixed with recycled thermoplastic rubber and virgin EVA. While previous technologies are limited to the extrusion of waste from the footwear industry and the use of virgin resin, the production process described in this patent presents significant differences: Types of waste used (Not limited to the footwear industry, also including waste from the textile, industrial and post-consumer industries. It does not use virgin resin or polyolefins in the production of the compound or the final product. Approximately 80% of the waste used consists of materials laminated with other components that are difficult to recycle due to their different chemical compositions and varying melting points. Its production process differs by not including the micronization step, and includes other steps, such as thermoelectric pressing and shaping, which are not present in previous processes.While prior art processes result in products obtained by injection molding, the product of the present invention is obtained by press melting. The end result is plastic sheets, which can be used in various applications, such as furniture, construction, and industrial processes.

[013] Document No. BR 102013002759-6, which deals with a “PROCESS FOR RECYCLING SHOES AND RESULTING PRODUCT”, comprises the following steps: (1) classification of shoes according to their material composition; (2) the selected shoes are ground in three phases of distinct particle sizes; (3) the ground material is palletized by friction; (4) micronization to reduce its particle size between 0.3 mm and 1.2 mm; (5) addition of granulated additives in percentages of 10 to 35%; (6) extrusion of the mixed material to form a continuous sheet (7); (8) coating of two or only one side of the continuous sheet (7) with layers of non-woven fabrics (9);(12) cross-sections (13), transforming into a first final product (14) which, in turn, includes a variation consisting of applying a lower layer of TNT - non-woven fabric (15), a first upper interface layer, preferably a polyethylene film (17) which constitutes an adhesive layer onto which a copolymer layer (19) is pressed, configuring other plates for later use in the manufacture of different products.; Petition 870250011509, dated 12 / 02 / 2025, page 19 / 23 / 8

[014] The described process involves classifying the materials, grinding them in stages of decreasing particle size, and micronizing them to reduce their size. The material is then extruded into a continuous sheet, which can be coated with non-woven fabric (TNT), forming semi-rigid plates. To make the different polymers present in the shoe waste compatible, the use of granulated additives, such as polyolefins, is necessary. This method focuses mainly on the production of specific products, especially coated plates. However, the use of compatibilizers increases costs and reduces the sustainability of the process. The present invention presents significant differences in relation to the aforementioned process, as it is not limited to the footwear industry, also encompassing waste from the textile, industrial (such as BOPP), and post-consumer waste (such as low-density polyethylene) industries.Furthermore, it does not use polyolefins or non-woven fabric (TNT) coating. The current method eliminates the micronization step and includes other steps, such as thermoelectric pressing and shaping. While the previous process obtains semi-rigid plastic sheets through extrusion, the current invention results in rigid plastic sheets obtained by melting in a press.

[015] Document No. BR 102016010600-1, which deals with an “INDUSTRIAL PLANT AND PROCESS FOR MANUFACTURING MATERIAL THROUGH THE RECYCLING OF INERT WASTE FROM THE FUSION SYSTEM”, characterized by inert waste that goes to a mill where it is crushed, forming a product of homogeneous granulometry that is deposited in trays arranged on a lifting table, then going to a loading rack and subsequently conveyed to a heating press at a temperature of 200°C, where it is pressed for approximately 15 minutes, forming unplumable slabs, which are directed to a cooling press, then to a discharge table where the slabs are loosened and stored.

[016] The method involves grinding the waste until a fine particle size is obtained, followed by thermal fusion of the materials. The present invention differs in that the waste used as raw material in the production process of the current compound includes waste from the footwear, textile, Petition 870250011509, dated 12 / 02 / 2025, page 20 / 23 / 8 industrial and post-consumer, while the waste used in the prior art is more limited in scope. The present invention presents a more robust process, incorporating additional steps such as agglomeration, extrusion and shaping of the plates.

[017] While the prior art operates at a fixed temperature of 200°C, the present invention uses a wider temperature range, between 200°C and 270°C. This allows fusion of polymer with different melting points, resulting in thermoplastic sheets with greater mechanical strength and dimensional stability. As well as, in the present invention, the pressing time varies from 8 to 30 minutes, depending on the thickness of the plates to be produced.

[018] Thus, it is a fact that the documents cited in the paragraphs above, despite belonging to the same field of application, do not present any of the characteristics of the object now improved, thus guaranteeing that it meets the legal requirements for patentability. BRIEF DESCRIPTION OF THE INVENTION

[019] Taking into account all the problems presented in the state of the art, the inventor, who possesses notable knowledge of the sector, created and developed the aforementioned “PROCESS FOR OBTAINING THERMOPLASTIC COMPOUND FROM INDUSTRIAL SOLID WASTE, RESULTING IN THERMOPLASTIC PLATES”, which aims to encompass the recycling process of complex industrial waste from different industrial sectors. Its objective is to contribute to the circular economy, as well as to promote an environmentally sustainable and technically viable solution for the treatment of mixed plastic waste, which was previously considered unviable to be recycled by simple methods.

[020] The objective of the present invention is to present a recycling process with polymers containing different chemical structures and melting points. The method overcomes the complexity of traditional recycling methods, which are generally specific to handling monomaterial or simple composition waste. What Petition 870250011509, dated 12 / 02 / 2025, page 21 / 23 / 8 results in low compatibility between polymers, hindering their function and compromising the quality of recycled products. The present invention combines grinding, agglomeration, thermomechanical processing and thermoelectric pressing to obtain a uniform compound. DESCRIPTION OF THE FIGURES

[021] To complement the present description in order to obtain a better understanding of the characteristics of the present invention and in accordance with a preferred practical embodiment thereof, a set of images is attached to the description, where, in an exemplary, though not limiting, manner, its operation is represented: Fig. 1 illustrates a flowchart image of the process for obtaining the thermoplastic compound; Fig. 2 shows a view of the present ground waste according to the patent application process; Fig. 3 shows a perspective view of the present plates assembled with polyester film; and Fig. 4 shows a top perspective image of the final product of the process. DETAILED DESCRIPTION OF THE INVENTION

[022] With reference to the illustrated images, the present invention patent refers to the “PROCESS FOR OBTAINING THERMOPLASTIC COMPOUND FROM INDUSTRIAL SOLID WASTE, RESULTING IN THERMOPLASTIC PLATES”, more precisely a process (10) for obtaining thermoplastic compound from industrial solid waste (1), including EVA laminated with polyester, nylon laminated with polyester, and synthetics based on PVC and polyurethane, Petition 870250011509, dated 12 / 02 / 2025, p. 22 / 23 / 8 also laminated with polyester are used in the range of 30 to 50%, resulting in thermoplastic sheet (7).

[023] According to the present invention, the process begins with the grinding stage (2) of the thermoplastic waste (1). This waste (1) is ground in a mill, passing through a sieve until it reaches a particle size in the range of 1 to 10 mm. After grinding (2), the particulate material (4) is directed to the agglomeration stage (5), where it is subjected to heat and friction under controlled conditions, with temperatures ranging between 100°C and 200°C and times between 3 and 15 minutes, resulting in a homogeneous mass (6).

[024] Next, on a work table with dimensions between 2 and 5 meters in length and 1 to 4 meters in width, the assembly (3) of the sheet (7) is carried out. For this, a biaxially oriented polyester film “BOPET” is positioned in such a way as to enclose the mixture, forming a sheet (7) weighing between 10 and 85 kg and with a thickness varying from 5 to 60 mm.

[025] The sheet (7) is then transferred to the pressing stage (8), carried out in a thermoelectric press. In this stage, temperatures between 210°C and 270°C allow the fusion between different polymers. After this phase, the formed sheet (7) is taken to a forming press (9), where it is compacted under pressures ranging from 150 to 350 bar.

[026] It is understood that when the present invention is put into practice, modifications may be introduced with regard to certain details of construction and form, without departing from the fundamental principles that are clearly substantiated in the claims, it being understood that the terminology used was not intended to be limiting. Petition 870250011509, dated 12 / 02 / 2025, page 23 / 23

Claims

CLAIMS 1) “PROCESS FOR OBTAINING THERMOPLASTIC COMPOUND FROM FROM INDUSTRIAL SOLID WASTE, RESULTING IN THERMOPLASTIC SHEETS”, conceives a process (10) for obtaining thermoplastic compound from industrial solid waste (1), resulting in thermoplastic sheets (7), which undergo grinding (2), sieving, agglomeration (5), coating and pressing (8) processes; characterized by starting with the grinding stage (2) of the crushed waste (1), and passing through a sieve reaching a particle size in the range of 1 to 10 mm; having the particulate material (4) directed to the agglomeration stage (5), being subjected to heat and friction under controlled conditions, with a temperature between 100°C and 200°C in an interval between 3 and 15 minutes, resulting in a homogeneous mass (6); following the table, where the assembly (3) of the sheet (7) is carried out, with a biaxially oriented polyester film, enveloping the mixture, forming a sheet (7);to be transferred to the pressing stage (8), in a thermoelectric press, with temperatures between 210°C and 270°C allowing the fusion of different polymers; compact under pressures between 150 and 350 bar in a forming press (9).; Petition 870250011509, dated 12 / 02 / 2025, page 15 / 23

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