Industrial Plastic Waste Research Articles

Valorization of Biomass and Industrial Wastes as Alternative Fuels for Sustainable Cement Production

The cement industry contributes around 7% of global anthropogenic carbon dioxide emissions, mainly from the combustion of fuels and limestone decomposition during clinker production. Using alternative fuels derived from wastes is a key strategy to reduce these emissions. However, alternative fuels vary in composition and heating value, so selecting appropriate ones is crucial to maintain clinker quality and manufacturing processes while minimizing environmental impact. This study evaluated various biomass and industrial wastes as potential alternative fuels, characterizing them based on proximate analysis, elemental and oxide composition, lower heating value, and bulk density. Sawdust, pecan nutshell, industrial hose waste, and plastic waste emerged as viable options as they met the suggested thresholds for heating value, chloride, moisture, and ash content. Industrial hose waste and plastic waste were most favorable with the highest heating values while meeting all the criteria. Conversely, wind blade waste, tire-derived fuel, and automotive shredder residue did not meet all the recommended criteria. Therefore, blending them with alternative and fossil fuels is necessary to preserve clinker quality and facilitate combustion. The findings of this research will serve as the basis for developing a computational model to optimize the blending of alternative fuels with fossil fuels for cement production.

Immiscible Polymer Blends Made from Industrial Shredder Residue Mixed Plastic with and without Melt Blending.

The processing of an immiscible polymer blend using melt blending (i.e., extrusion) often results in a polymer material with inferior mechanical performance compared with its virgin counterparts. Here, we report and compare the properties of immiscible polymer blends produced from industrial mixed plastic waste from shredder residue comprising at least four different polymers (acrylonitrile butadiene styrene, polystyrene, polypropylene, and polyethylene) with and without a prior melt-blending step employed. As anticipated, mixed plastic blend produced with a prior melt-blending step exhibited a more homogeneous microstructure, resulting in brittleness, poor work of fracture, and single-edge notched fracture toughness with a flat R-curve. Without the intimate polymers mixing arising from melt blending, the resulting mixed plastic blend was found to possess a more heterogeneous concentric ellipsoid microstructure with large single polymer domains. This mixed plastic blend demonstrated progressive failure under uniaxial tensile loading, along with a more ductile single-edge notched fracture toughness response accompanied by a growing R-curve. Digital image correlation and fractographic analysis revealed that melt blending created a large number of incompatible polymer boundaries that acted as stress concentration points, leading to brittleness and earlier onset catastrophic failure. The more heterogeneous mixed plastic blend produced without using a prior melt-blending step contains a smaller number of incompatible polymer boundaries. Additionally, the presence of larger single polymer domains also implies that the mechanical characteristics of the single polymer can be exploited in the immiscible mixed plastic blend. Our work opens up a simple pathway to add value to mixed plastic waste from shredder residue for use in engineering applications, diverting them away from landfill or incineration.

Innovations for sustainable chemical manufacturing and waste minimization through green production practices

Abstract In the current scenario, a green product is designed to have a minimal impact on the environment as it is made from recycled materials. In the highly energy-intensive industry, green production has a significant influence on business sustainability. The intelligent environment around us created an unavoidable problem, because of the uncontrolled growth in waste materials like plastic and electrical trash. Both seriously endanger the environment, wildlife, and human health, trash has an impact on societal structures and financial systems in future generations. Industrial and domestic plastic wastes, which are dumped in landfills or the environment, are mostly made of polyethylene (PE) polymers. These wastes’ polymeric nature makes them difficult for microorganisms to degrade. Incorporating biological and chemical processes together is facilitated by pyrolysis and the biodegradation of alkenes to achieve the maximum biodegradation of PE plastics, as proposed in this study, to reduce plastic waste. This research outcome demonstrates that the Waste plastic recycling plant dataset is taken to show the decomposition of high-density PE plastic to simpler alkene with microbial-assisted degradation of alkene to biomass through bacterial communities. Communities of microbes from three different environments inoculating at three nutrient levels are monitored for their ability to degrade model alkenes (with several carbon atoms) within 5 days. There is Plenty of evidence indicating that the nutritional content significantly influences the rates at which hydrocarbons are broken down. These findings imply that the microorganisms required for alkene breakdown are present in a wide range of ambient microbial communities and are significantly chosen under optimized environments such as nutrient enrichment.

Fine-tuning DETR: Toward holistic process in plastic waste sorting system

Every year human discharges about 350 million tons of plastic waste into the environment and can be projected to triple in 2060 without any attempts to change situation. From 1970 to 2019, an estimation of 130 million tons of plastic waste was accumulated into the rivers, lakes and sea, while only 27 % is recycled and utilized. Moreover, waste treatment plants in most places around the world are using out-of-date technology, may pose a threat to the health of the workers. Therefore, it is essential to modernize these systems for protecting human health. This paper proposes fine-tuning DETR, which applies Artificial Intelligent in plastic waste sorting system. Consequently, this study analyzed the applicability of fine-tuning DETR in the domain of plastic waste categorization and its potential drawbacks. For fair experiment and evaluation, model candidates were trained and evaluated on an industrial plastic waste dataset. The fine-tuning DETR outperformed other candidates in the context of critical indicators, from accuracy (25.1 mAP), processing speed (28 FPS) to computational cost (GFLOPs 86). Furthermore, fine-tuning DETR possesses the capability of autonomous operation without requiring human intervention, distinguishing this candidate from other prevalent algorithms. Our research demonstrates that, fine-tuning DETR specifically and Transformer-based algorithms in general, are entirely suitable and hold significant potential for large-scale application in holistic plastic waste sorting systems.

Optical detection of plastic waste through computer vision

An incredibly wide range of plastic products and enormous volumes of generated plastic wastes makes sorting technologies highly important. In order to enhance the efficiency and accuracy of sorting process, this article proposes an Internet of Video Things solution based on the deep learning algorithms for image recognition of plastic waste on a moving conveyor belt and embedded intelligence. In particular, the state-of-the-art object detection models, including Faster R-CNN, RetinaNet and YOLOv8 are used. Target categories of plastic are Polyethylene Terephthalate (PET) and Polypropylene (PP). Furthermore, we implemented quantization techniques for trained models on a commercial off-the-shelf embedded system for fast processing time. We achieved a high mean Average Precision (mAP) metric of 77.74% and accuracy of 95.67% on a test set and are fine-tuned and optimized for the deployment on an Nano embedded system providing 20 frames per second. This research contributes to the field of application of Internet of Things by demonstrating the efficacy of deep learning algorithms run on the embedded system in the industrial plastic waste sorting process. The findings highlight the practical applicability of these algorithms and offer insights into resource management and recycling practices.

Design of polyurethane composites obtained from industrial plastic wastes, pyrite and red mud

The purpose of this study consisted in the synthesis and characterization of composite materials based on polyurethane (PUR) rigid foam reinforced with two industrial wastes such as pyrite and red mud for the retention of mercury ions, Hg2+, ions from contaminated water and applications as paving stones in construction area. The diol used to create the urethane bond resulted from the depolymerization of poly(ethylene terephthalate) (PET) wastes in the presence of diethylene glycol (DEG). The resulted diol was characterized by gel permeation chromatography (GPC), registering a molecular weight, Mn = 420 g/mol. The hydroxyl index of the diol, IOH = 256.731 mgKOH/g was determined based on ASTM D4274-99. In this study, 6 types of PUR foams were obtained by reacting the diol with the polycondensation agent, 4,4′-methylene diphenyl diisocyanate (MDI) in the presence of different concentrations of filling agents. All specimens were characterized by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), EDX mapping, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and compression tests. The formation of urethane group was confirmed by FT-IR for all specimens. The porous structure of the PUR foams was evidenced by SEM, while (EDX) and EDX mapping were used to analyze the elemental composition of the composite materials and the uniform distribution of the filling agents within the cellular structure. TGA proved that both types of PUR foams increased their thermal resistance compared with blank samples. However, the specimens loaded with red mud exhibited increased thermal resistance as the concentration of red mud was increased compared with pyrite-based samples. The final residual mass registered for red mud was 24%, compared with pyrite-based samples that registered 21%. Unexpectedly, the DSC analysis indicated that Tg values decreased up to 47 °C as the pyrite concentration was increased compared with blank sample (57 °C), while the Tg values for red mud-based samples increased as the concentration of the red mud was increased up to 60 °C. Similar results were confirmed by the compression tests, this behavior being attributed to pyrite aggregate formation in PUR matrix and confirmed also by the density values for which a correlation between the filling agent concentration and density was not possible. In the case of red mud-based PUR foams the mechanical resistance decreased as the concentration of the filling agent was increased as expected.

Discussion on “Thermal and mechanical characterization of composite materials from industrial plastic wastes and recycled nylon fibers for floor paving tiles application” by Owen et al., Waste Management 166 (2023) 25–34

Discussion on “Thermal and mechanical characterization of composite materials from industrial plastic wastes and recycled nylon fibers for floor paving tiles application” by Owen et al., Waste Management 166 (2023) 25–34

Thermal and mechanical characterization of composite materials from industrial plastic wastes and recycled nylon fibers for floor paving tiles application

Industrial plastic waste is growing globally at an alarming rate and environmental pollution from traditional landfill disposal and incineration treatments are of great concern. As a strategy to reduce plastic pollution, value-added composite materials from industrial plastic wastes reinforced with recycled nylon fibers for use in floor paving tile applications were developed. This is to address the disadvantages of existing ceramic tiles which are relatively heavy, brittle, and expensive.The plastic waste composite structures were produced via compression molding technique at an optimized randomly oriented constant fiber volume fraction of 50 wt% after the initial sorting, cleaning, drying, pulverizing, and melt-mixing. The molding temperature, pressure, and time for the composite’s structures were 220 ℃, 65 kg.cm−3, and 5 min respectively. The composites' thermal, mechanical, and microstructural properties were characterized in accordance with appropriate ASTM standards. From the results obtained, the differential scanning calorimetry (DSC) of mixed plastic wastes and nylon fiber wastes showed a processing temperature range of 130–180 ℃, and 250 ℃ respectively. Thermal degradation temperature (TGA) of the plastic and nylon fiber waste composites were stable above 400 ℃ with maximum bending strength, however, the reinforced plastic waste sandwiched composite structures had outstanding mechanical properties indicating unique characteristics suitable for floor paving tiles. Hence, the current research has developed tough and lightweight tiles composites that are economically viable, and their application will contribute to the development of the building and construction sectors thereby reducing about 10–15% of annual plastic waste generation and a sustainable environment.

New insight of Mn(III) in δ-MnO2 for peroxymonosulfate activation reaction: Via direct electron transfer or via free radical reactions

Due to the increasing of industrial plastic waste and its refractory characteristics, it is extremely urgent to develop new degradation technology and environmentally friendly catalyst for industrial plastic waste. Manganese oxides are one of the most promising candidates for the catalytic degradation of plastic wastes. However, an improved understanding of the structural properties affecting their catalytic activity is required for high-efficient wastewater treatment. We herein report the surface reactivity effects of δ-MnO2 structural defects with regards to Bisphenol A (BPA) degradation/probe in the presence of peroxymonosulfate (PMS). Four δ-MnOx samples with different Mn(III) contents (different Mn(III)-deficient sample) were prepared and their structural properties as well as surface reactivity were characterized by batch test, ESR and XAFS analysis. For the Mn(III)-deficient sample, BPA removal was principally affected by direct electron transfer, with the adsorbed BPA degraded following hydroxylation. In contrast, a small fraction of Mn(III) substitution in δ-MnO2 could significantly encouraged the activation of PMS to produce SO4−☐and ☐OH, and a BPA degradation via beta scission. Moreover, the Mn(III)-rich δ-MnO2 demonstrate a high BPA removal rate even with a low sample load, which performed well following a reuse of five times. Our results provide a new way for the improvement of δ-MnO2 activity for the use of industrial plastic wastes treatment.

Pyrolytic Depolymerization Mechanisms for Post-Consumer Plastic Wastes

Fast pyrolysis of five post-consumer plastic waste materials was studied using pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS) technique. Prescription medicine bottles, landfill liners, and one type of industrial plastic waste represented polyolefin-based polymers, whereas packaging material represented polystyrene, and other industrial plastic waste represented polyurethane. The noncatalytic and catalytic degradation mechanisms of all five post-consumer plastic wastes were elucidated. The noncatalytic pyrolysis experiments were conducted at a temperature of 600 °C for a residence time of 5 min. For catalytic pyrolysis, a spent FCC catalyst was utilized for polystyrene, a sulfated zirconia-based catalyst was utilized for polyurethane, and a Y-zeolite catalyst was used for polyolefinic plastic waste. The results suggested that the thermal reaction has higher monomeric and oligomeric selectivity than the catalytic reaction. Results from the catalytic runs showed that the addition of catalysts greatly influences product compositions and has a significant effect on the selectivity of a specific compound. One of the plastic wastes, landfill liner, was selected for a batch scale pyrolysis at 420–440 °C using Y-zeolite as a catalyst to demonstrate the product properties and potential use of the liquid product formed. The complete product distribution of plastic crude oil was performed followed by distillation to produce aviation range fuel. The fuel properties of aviation range fuel were examined, and results suggested that the fuel fraction can be easily blended with commercially available fuels for direct applications.

Problems and Challenges on Environmental Law Enforcement in Indonesia: AMDAL in the Context of Administrative Law

Environmental issues have been increasingly recognized as significant challenges facing Indonesia, as a developing country with a rapidly growing population and a rapidly expanding economy. In recent years, environmental degradation and natural resource depletion have become more acute, resulting in increased pressure on the government to take stronger action to protect the environment. Despite the existence of environmental laws in Indonesia, environmental degradation continues to occur, highlighting the need for better enforcement and stronger legal protections. One of the major environmental problems in Indonesia is deforestation, which is driven by the expansion of agricultural land, mining activities, and logging. This has resulted in significant habitat loss and biodiversity decline, as well as increased greenhouse gas emissions from the loss of forest cover. Additionally, Indonesia’s coastline and marine ecosystems are threatened by pollution from industrial activities and plastic waste, which has adverse effects on marine life and human health. Environmental laws in Indonesia include a range of regulatory measures, such as the Environmental Impact Assessment (EIA) and Forest Law Enforcement, Governance and Trade (FLEGT) programs. However, the implementation of these laws is often inadequate, with weak enforcement and a lack of effective penalties for non-compliance. Moreover, corruption and lack of political will have been identified as key factors that hinder the effective implementation of environmental laws in Indonesia.

AI Techniques Aid for Optimizing the Collection System of Industrial Plastic Waste

AI Techniques Aid for Optimizing the Collection System of Industrial Plastic Waste

Collection of Industrial Plastic Waste During the COVID-19 Pandemic: A Case Study of the Wholesale and Retail Trade Sector in Fukuoka Prefecture, Japan

Collection of Industrial Plastic Waste During the COVID-19 Pandemic: A Case Study of the Wholesale and Retail Trade Sector in Fukuoka Prefecture, Japan

How an incineration tax changes waste management practices among firms

Sustainable management of industrial plastic waste is crucial in the transition to a circular economy. Today, most industrial plastic waste is incinerated, whereas it could be recycled. As a consequence, governments increasingly make use of incineration taxes to improve current waste management practices. This paper presents an econometric panel analysis that studies the effects of an incineration tax on industrial plastic waste in Flanders (Belgium). Not only is this study the first econometric analysis on industrial plastic waste management in which firm heterogeneity is explicitly taken into account by including firm-specific characteristics, but this study also provides policymakers with insights into the effectiveness of an incineration tax to change current waste management practices. Empirical estimates imply that heterogeneous firms generate industrial plastic waste in different ways and that heterogeneous firms reduce their waste generation in different ways after the incineration tax rate increases. The estimates also show that the unique decrease of the incineration tax in 2007, did not change waste management practices. These estimates show that firms do not disinvest or indicate that loss aversion theory, i.e. a preference for avoiding losses over acquiring equivalent gains, might apply to firms that are faced with environmental taxation in a waste management context.

AI Techniques Aid for Predicting the Collection Demands of Industrial Plastic Waste From Multiple Facilities

AI Techniques Aid for Predicting the Collection Demands of Industrial Plastic Waste From Multiple Facilities

Batch Hydrothermal liquefaction of end-of-life plastic and oil characterization

Finding a proper way to manage the enormous amount of waste plastic that is globally produced, is one of the main environmental challenges of our times. Among the different types of chemical recycling, Hydrothermal Liquefaction (HTL) appears as a potential method for the treatment of plastic waste mixes, for sustainable production of biocrude or chemicals with high added value. In this work hydrothermal liquefaction reactions were carried out on a polymeric residue, obtained from an industrial plastic waste collection and recycling process. The residue has a heterogeneous composition consisting not only of polymers but also paper and metals. Two batch experiments were performed in a stainless-steel Parr autoclave at 340 °C, investigating a residence times of 5 hours and the use of an alkaline catalyst (NaOH). The oils obtained from the reactions, as well as the aqueous phases, have been analysed by different analytical techniques such as: FT-IR spectroscopy, GC-MS, GC-FID, IC. The operating conditions used in this work, allowed the degradation of cellulose and polymers with reactive sites for hydrolysis such as PET, nylon and PVAc, while polyolefins (PE, PP) were not attacked. The use of a basic catalyst favoured a greater hydrolysis rate.

CO-PYROLYSIS CANGKANG KELAPA SAWIT DAN LIMBAH PLASTIK KEMASAN

In the present study, the co-pyrolysis of biomass waste, i.e. palm kernel shells (PKS) and industrial packaging plastic waste, namely polyethylene terephthalate (PET) and polyethylene (PE) were conducted. Prior to the pyrolysis, the raw materials were analyzed by thermogravimetric and elemental procedures. The pyrolysis was conducted in a fixed bed reactor which was heated from room temperature to 500 °C in an N 2 atmosphere with a heating rate of 10 °C/min. The raw materials were weighted and mixed together manually with variations of weight composition ratios between biomass and plastic, i.e. 100% biomass (100/0); 90% biomass and 10% plastic (90/10); 70% biomass and 30% plastic (70/30); 50% biomass and 50% plastic (50/50); and 100% plastic (0/100). Then, they were put under pressure to obtain a pellet. The synergistic effect of biomass and plastic was investigated to see the difference between the pyrolysis products yields in theory and experiment. The bio-oil products were characterized by several methods and showed the potential to be used as a fuel. The optimum condition was obtained from 50/50 weight composition ratio. It was gained 30% improvement of the higher heating value of bio-oil, and the percentage area of hydrocarbon was contained in bio-oil increased from 4.68% to 53.40%.

Mathematical modeling on investments in burning and recycling of dumped waste by plastic industry

Every year tones of plastic are produced and people become the victim of many types of waste including domestic, agronomic and industrialized waste. In this paper, we have constructed the mathematical model to examine the rising pollution level due to industrial plastic waste and the process of destroying or renovating this plastic waste using several toxic chemicals. The dynamical model suggests investing the influential part of the budget into civilization health policy, like reducing the plastic burning and support the installation of the eco-friendly plastic recycling machine to reuse dumped industrial plastic. Both of these policies are strides to the health as well as the economic progress of the country. In the model, the local stability of the system of nonlinear differential equations is qualitatively analyzed with appropriate conditions. Graph theory results help to distinguish the global stability behavior of the model. Techniques to reduce plastic pollution are outlined by optimizing both the policies which are simulated numerically with given validated data.

Pyrolysis of Polyethylene Terephthalate over Carbon-Supported Pd Catalyst

Pyrolysis of polyethylene terephthalate (PET) produces polycyclic hydrocarbons and biphenyl derivatives that are harmful to human health and the environment. Therefore, a palladium metal catalyst (5 wt.% Pd loaded on activated carbon) was used to prevent the formation of harmful materials. When a Pd catalyst/PET ratio of 0.01 was applied in pyrolysis of PET, it did not show a meaningful difference in the generation of polycyclic hydrocarbons and biphenyl derivatives. However, when a Pd catalyst/PET ratio of 0.05 was used during pyrolysis, it prevented their formation and generation at experimental temperature ranges (400–700 °C). For example, the concentration of 2-naphthalenecarboxylic acid produced, which is a typical polycyclic hydrocarbon material, was reduced by 44%. In addition, the concentration of biphenyl-4-carboxylic acid, which is contained in biphenyl derivatives, was reduced by 79% compared to non-catalytic pyrolysis at 800 °C. This was because the ring-opening reaction and free radical mechanism caused by the Pd catalyst and thermal cracking were dominant during the pyrolysis of PET. Apart from these materials, amine compounds were generated as products of the pyrolysis of PET. Amine concentration showed a similar trend with polycyclic hydrocarbons and benzene derivatives. Based on these results, the total concentration of polycyclic hydrocarbons and biphenyl derivatives was compared; the results confirmed that the concentrations of all substances were reduced. This research suggests that a metal-supported catalyst will help create a more environmentally friendly and reliable method of industrial plastic waste disposal.

Characterization and Distillation of Pyrolysis Liquids Coming from Polyolefins Segregated of MSW for Their Use as Automotive Diesel Fuel

The liquids resulting from pyrolysis of industrial plastic waste (IPW) and postconsumer colored and white plastic film waste (PCPW and PWPW, respectively) at the pilot scale (80 kg/h) were widely c...