Maximizing olefin production via steam cracking of distilled pyrolysis oils from difficult-to-recycle municipal plastic waste and marine litter

Plastic waste management, a matter for the 'community'.

Plastics and climate change—Breaking carbon lock-ins through three mitigation pathways

Dehalogenation is a key technology in the feedstock recycling of mixed halogenated waste plastics. In this study, two different methods were used to clarify the effectiveness of our proposed catalytic dehalogenation process using various carbon composites of iron oxides and calcium carbonate as the catalyst/sorbent. The first approach (a two-step process) was to develop a process for the thermal degradation of mixed halogenated waste plastics, and also develop dehalogenation catalysts for the catalytic dehydrochlorination of organic chlorine compounds from mixed plastic-derived oil containing polyvinyl chloride (PVC) using a fixed-bed flow-type reactor. The second approach (a single-step process) was the simultaneous degradation and dehalogenation of chlorinated (PVC) and brominated (plastic containing brominated flame retardant, HIPS–Br) mixed plastics into halogen-free liquid products. We report on a catalytic dehalogenation process for the chlorinated and brominated organic compounds formed by the pyrolysis of PVC and brominated flame retardant (HIPS–Br) mixed waste plastics [(polyethylene (PE), polypropylene (PP), and polystyrene (PS)], and also other plastics. During dehydrohalogenation, the iron- and calcium-based catalysts were transformed into their corresponding halides, which are also very active in the dehydrohalogenation of organic halogenated compounds. The halogen-free plastic-derived oil (PDO) can be used as a fuel oil or feedstock in refineries.

The impacts of plastics’ life cycle

Mass production of hierarchically porous carbon nanosheets by carbonizing “real-world” mixed waste plastics toward excellent-performance supercapacitors

Analysis of products from the pyrolysis and liquefaction of single plastics and waste plastic mixtures

As the use of plastic products is very widespread, reuse of the plastic waste represents a huge challenge. Plastic packaging (e.g. thin plastic bags, foil, foodwrappings) and other plastic waste (pallets, garden furniture, buckets, sport and hobby equipment, car bumpers, canisters, pipes, bobbins, computer and TV cases, plastic refrigerator details, etc.) form the most problematic and continuously growing type of waste, that according to common solutions can be mainly landfilled, or incinerated.Initial sorting of waste and subsequent recycling of single-type plastics into uniform mass, granules or new products are the generally preferred solutions for recycling plastic. Recycling is normally performed based on one specific type of plastic, e.g. LDPE, HDPE, PS, PP or PET, in the course of which the sorted plastic waste is washed, shredded, dried and granulated. The biggest problem with mixed plastics is posed by the fact that polymers of different types are immiscible because of their different molecular weights and long polymer chains. Heating the polymers is not sufficient for decomposing polymer molecules; therefore, the polymers to be recovered must typically have identical compositions to achieve effective mixing. When plastics of different types are simultaneously melted together, they usually do not mix – like oil and water – and will form layers. Low-grade mixed dirty plastic is typically rejected from recycling. Rexest Grupp Ltd, however, has developed a technology for recycling mixed plastic waste.In this study it has been discovered that mixed plastic waste that was landfilled for over a decade did not differentiate from the fresh mixed plastic, neither had the landfilled plastic lost its polymeric properties. Landfilled plastic needs only to be separated from other materials (eg textile, paper) and soil. After mechanical separation, recycling technologies that are able to use of mixed plastic waste, were as also able to handle mixed landfill plastic.Experiments demonstrate that construction materials and products like decking boards, noise barriers, garden furniture etc. could therefore be produced also from landfilled plastic waste, turning this waste into the maintenance free products that are also recyclable after decades of use. Taking into account vast number of landfills that contain plastic waste it raises question whether turning these materials into recyclable construction materials could form a new challenge and possibility to support the environment, and lower the need for the usage of new resources.

High and low density polyethylene, HDPE and LDPE; polypropylene, PP; polystyrene, PS; and polyethyleneterephthalate, PET) make up the majority of municipal plastic waste (MPW). The goal of this study was to create a kinetic model to apply thermogravimetric analysis to uncover the real reaction mechanism of mixed waste plastic (TGA). To determine the mechanism of MPW pyrolysis, a variety of techniques including Kissinger, Akahirae-Sunose, KAS, Malek, and linear model fitting were used. The results were evaluated using experimental data from TGA. Five types of waste plastic waste decomposition on different setpoint(10 ̊C/min & 20 ̊C/min), temperature of 30 ̊C to 530 ̊C and the sample size 1-4 mm. in the model fitting method we use the criado method. As a result of the fluctuation in apparent activation energy with conversion and kinetic model with heating rate, the results demonstrated that a complicated process, rather than a simple 1st order, occurs during the breakdown. Key words: Mixed waste plastic, Thermogravimetric analysis, Kinetic parameters, Decomposition model etc.

On November 28, 2022, LyondellBasell and Audi announced a first-time collaboration to help close the loop for mixed automotive plastic waste. Audi is installing plastic seatbelt buckle covers in the Q8 e-tron made using LyondellBasell plastic that supports the sourcing of feedstocks from mixed automotive plastic waste. Plastic components from customer vehicles that can no longer be repaired are dismantled, shredded, and processed by chemical recycling into pyrolysis oil. The pyrolysis oil is then used as a raw material in LyondellBasell's manufacturing process for the production of new plastics, replacing virgin fossil feedstocks. The recycled content is attributed to the Audi product via a mass balance approach.

Marine litter is a crucial health and environmental issue in the global sense for not only humankind but also for cetaceans, marine life, and other flying and land animals. It is known that marine litter has significant environmental, economic, health, and aesthetic effects. Marine litter is a permanent, manufactured, or processed solid material which is discarded, disposed, or abandoned from any source into marine and coastal environments. It can be composed of the wastes and particles of abandoned waste textile products, synthetic garments and their fragments, fishing nets, fishing lines, industrial product wastes and industrial plastic production wastes such as plastic bottles and plastic containers (mostly made from synthetic polymers), vehicle tire dusts, and breakdown of litter and cosmetic products. In most cases, plastics are one of the most important components of marine litter because of their very slow decay rates. It is stated that approximately 90% of the marine litter is composed of plastic material wastes and 5–13 million tonnes of plastic waste litter are released to the marine-related environment per year. The amount of plastic waste in the seas is likely to continue to increase, mainly due to the negative increase in plastic consumption (about 9% per annum) and the inadequacy of its reuse, recycling, and waste management practices. The entanglement and ingestion of marine litter directly damage wild animals and their environment. Accumulation of marine litter on the seabed, accumulation of trash, and seagrass deposits in coral reefs cause damage to the natural habitat and damage the ecosystem. Plastic entanglement and ingestion problems by the animals are the main issues with macroplastics. On the other hand, plastic ingestion and accumulation problems by the animals are the main issues with microplastics. Microplastics in marine litter can be generated through microbeads, pellets, abrasion of especially car tires, textile materials and textile products, the decay of mesoplastics and macroplastics, and so on. Microfibers and microfibrils, which may be generated during ordinary home laundry cycles due to the agitation and beating nature of the washing process and end up in sewage, are also a subcategory of microplastics. Ingestion of microplastic and microparticle marine litter can cause many health problems. Microplastics in the sea enter the body of living sea creatures. As a result of these marine organisms, such as fishes, being consumed by humans, these microplastics and their remnants enter the human body and cause further health problems. Plastic materials enter to the seas and oceans end up on ocean floor, sea sides, beaches, and ocean surfaces. Unfortunately, degradation of these plastic waste litters in the marine environment needs centuries. Various measures are taken to remove the plastic wastes from the seas and seashores. Coastal cleaning activities and cleaning nets taken to the coasts are some of the most commonly used methods. The most common approaches for collected marine litter can also be storage or incineration. However, these methods may not be always ideal solutions because of limited storage space and pollution risks. The most likely solution for the destruction of plastic marine litter is the plastic recycling technologies commonly used in the processing of industrial wastes. The waste plastic and plastic parts collected from the seas and seashores are separated from each other by various methods and then each type of the recovered polymer, such as polyethylene terephthalate (PET) polymer, polypropylene (PP) polymer, and polyamide (PA) polymer, can be included in the recycling processes at their relevant recycling facilities. Plastic recycling technologies can typically be classified in three ways: mechanical recycling, chemical recycling, and thermal recycling. In this chapter, marine litter and recycling of marine litter and ocean plastics are comprehensively reviewed. First of all, the information regarding marine litter sources, marine litter types, and the contribution of synthetic fibers to marine litter via laundry (washing) cycles is given. Then, the ecological and socioeconomic effects of marine litter are discussed. Afterward, the precautions against marine litter and recycling of marine litter (mechanical recycling, chemical recycling, and thermal recycling) are mentioned. Finally, the recent commercial developments for marine litter recycling are covered.

Feedstock recycling has received attention as an effective method to recycle waste plastics. However, estimating the reduction potential by life cycle assessment using coke oven and blast furnace in steel works has been a challenging task due to the complex structure of energy flow in steel works. Municipal waste plastics consist of several plastic resins. Previous studies have generally disregarded the composition of waste plastics, which varies significantly depending on the geographical area. If the reduction potentials by using each plastic resin in steel works can be quantified, the potential of municipal waste plastics (mixtures of plastic resins) can be estimated by summing up the potential of each resin multiplied by the composition of each resin in municipal waste plastics. Therefore, the goal of this study is to investigate the reduction potentials of CO2 emissions by using individual plastic resins (polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET)) and those for municipal waste plastics in the coke oven and blast furnace. A model was developed to clarify the energy flow in steel works. In order to estimate the changes in energy and material balance in coke ovens when waste plastics are charged, the equations to calculate the coke product yield, gas product yield, and oil product yields of each plastic resin were derived from previous studies. The Rist model was adopted to quantify the changes in the inputs and outputs when plastics were fed into a blast furnace. Then, a matrix calculation method was used to calculate the change in energy balance before and after plastics are fed into a coke oven. It was confirmed that product yields of municipal waste plastics (mixtures of plastic resins) could be estimated by summing up the product yield of each plastic resin multiplied by the composition of each resin in municipal waste plastics. In both cases of coke oven and blast furnace feedstock recycling, the reduction potential of CO2 emissions varies significantly depending on the plastic resins. For example, in the case of coke oven chemical feedstock recycling, the reduction potential of PS and PP is larger than that of PE. On the other hand, in the case of blast furnace feedstock recycling, PE has the largest CO2 emissions reduction potential, whereas the CO2 emission reduction potential of PP is smaller than those of PE and PS. In both cases, PET has negative CO2 emission reduction potentials, i.e., there is an increase of CO2 emissions. In addition, the reduction potentials of CO2 emissions are slightly different in each city. The differences in the reduction potentials of CO2 emissions by coke oven chemical feedstock recycling of each plastic resin is attributable to the differences in calorific values and coke product yields of each plastic resin. On the other hand, the difference in the CO2 emission reduction potential for each plastic resin in blast furnace feedstock recycling is attributable to the difference in calorific values and the carbon and hydrogen content of each plastic resin, which leads to a difference in the coke substitution effect by each plastic resin. In both cases, the difference in those of municipal waste plastics is mostly attributable to the amount of impurities (e.g., ash, water) in the municipal waste plastics. It was found that the reduction potential of CO2 emissions by coke oven and blast furnace feedstock recycling of municipal waste plastics (mixtures of plastic resins) could be estimated by summing up the potential of each resin multiplied by the composition of each resin in municipal waste plastics. It was also clarified that feedstock recycling of waste plastic in steel works is effective for avoiding the increase in CO2 emissions by incinerating waste plastics, such as those from household mixtures of different resins. With the results obtained in this study, reduction potentials of CO2 emissions can be calculated for any waste plastics because differences in composition are taken into account.

Thermal degradation of waste plastics under non-sweeping atmosphere: Part 1: Effect of temperature, product optimization, and degradation mechanism

A few times a year, volunteers fan out along the causeway that links the South Carolina mainland with the seashore community of Folly Beach to clean up plastic bottles, straws, bags, and other debris from along the road and the salt marsh. Some of this debris has come from cities miles away. On windy days, litter is often blown off city streets into waterways. During rainstorms, debris floats into drains that empty into rivers. Other trash probably came from places closer to home. “I see bags and other plastic flying off the beds of pickup trucks going down the causeway,” says Marty Morganello, who organizes the cleanups for the Charleston-area chapter of the nonprofit Surfrider Foundation. “I see them coming out the open windows of cars and out the backs of garbage trucks and even recycling trucks. This material is lightweight, and if you don’t secure it, it will fly away.” By one estimate, the volume of plastic debris going into the world’s oceans could more than double by 2025, assuming current trends in coastal development and plastics use. Some countries have begun identifying ways to improve management of plastic ... Beach cleanups yield enormous amounts of trash, with plastic items a major constituent.1 Although the human health impacts of this marine plastic pollution remain poorly characterized, it is widely seen as an emerging problem that deserves much more research attention.2 Likewise, there is a growing urgency among industry, government, nongovernmental organizations, and environmental groups to develop tools and policies to track, capture, and recycle plastic waste before it reaches the ocean.

Maximising naphtha-range hydrocarbons from thermal pyrolysis of polyolefin-rich mixed plastic waste by split-plot response surface methodology.

Determination of biomass content in combusted municipal waste and associated CO2 emissions in Estonia