Plastic Waste Generation Research Articles

Chemical recycling of waste plastics for new materials production

Once referred to as ‘materials of 1,000 uses’, plastics meet demands in everything from clothing and automotive sectors to the manufacturing of medical equipment and electronics. Concomitant with usage, worldwide generation of plastic solid waste increases daily and is currently around 150 million tonnes per annum. Although recycled materials may have physical properties similar to those of virgin plastics, the resulting monetary savings are limited and the properties of most plastics are significantly compromised after a number of processing cycles. An alternative approach to processing plastic solid waste is chemical recycling, the success of which relies on the affordability of processes and the efficiency of catalysts. In this Review, we describe technologies available for sorting and recycling plastic solid waste into feedstocks, as well as state-of-the-art techniques to chemically recycle commercial plastics. These evaluations are followed by a survey of recent advances in the design of new high-performing recyclable polymers. Many methods exist for the recycling of plastic solid waste. Chemical recycling, which can take many forms from high-temperature pyrolysis to mild, solution-based catalytic depolymerization, can afford enormous economic and environmental benefits. This Review covers the state of the art in chemical recycling and the design of high-performance polymers amenable to such processes.

Mechanical performance of asphalt mixtures using polymer-micronized PET-modified binder

The global engineering plastics market has been growing as it replaces materials such as glass and metal. It can be used in a wide variety of products and technologies in other sectors of the economy such as energy generation, automotive, maritime, construction, electronics, packaging, and others. However, this increase in global use presented problems with respect to the increase in plastic waste generation. The existence and destination of plastic waste in the soil and hydric resources has been recognised as an emerging issue in preserving the environment. In this research, Micronized Polyethylene Terephthalate (micronized PET) was used as an additive for asphalt mixtures. The polymer was mixed in amounts of 4%, 5%, and 6% by weight with an asphalt binder base and mechanical tests were performed. Two SUPERPAVE mix design methods were performed. The first one was made with pure binder and the optimum binder content was determined and the specimens were analysed according to the following parameters: Resilient Modulus (RM), Lottman, and Indirect Tensile Strength (ITS). A second mix design procedure was performed with the optimum PET content according to the best results obtained in the first one, and analysed according RM, ITS, Lottman, Fatigue, and Flow Number tests. The results show significant improvements on mechanical properties of the asphalt mixtures with micronized PET compared with asphalt mixtures without additive.

GENERACIÓN, LEGISLACIÓN Y VALORIZACIÓN DE RESIDUOS PLÁSTICOS EN IBEROAMÉRICA

Los plasticos son una de las corrientes de residuos que ha despertado mayor interes en los ultimos anos, debido a su continuo crecimiento y a sus efectos ambientales, que incluyen la saturacion de sitios de disposicion final y afectaciones en los ecosistemas, a los que llegan debido a un manejo inadecuado. En esta investigacion se analizan y comparan la generacion de residuos plasticos no industriales, las medidas legislativas abocadas a la minimizacion de sus impactos y las tendencias de valorizacion. La generacion de residuos plasticos oscila entre el 9 y el 14 % de la masa de residuos solidos urbanos, con una tendencia a aumentar en forma directa con el producto interno bruto de los paises y en las grandes zonas metropolitanas. Con el fin de dar un manejo integral a estos residuos los paises han adoptado medidas que incluyen legislaciones especificas, normas, sistemas de acopio y de informacion. Un caso relevante, por sus connotaciones ambientales, es el de las bolsas de plastico; las medidas adoptadas a este respecto incluyen su prohibicion o la sustitucion por bolsas biodegradables. En cuanto a la valorizacion, se detecta un incremento en el reciclaje, a traves del acopio formal e informal. Las medidas establecidas, especialmente en America Latina, han tenido un impacto aun limitado, debido principalmente a la falta de articulacion entre las mismas, la produccion de plasticos y el sistema de gestion de residuos.

Development of pea protein-based bioplastics with antimicrobial properties.

In the present work, bioplastics from renewable polymers were studied in order to reduce the huge generation of plastic wastes, causing an environmental problem that continues owing to the increasing demand for plastic products. Bioplastics with much better antimicrobial properties, in particular against Gram-positive bacteria, were obtained with the addition of nisin to the initial protein/plasticizer mixture. However, the addition of nisin produces more rigid but less deformable bioplastics (higher Young's modulus but lower strain at break). The results obtained are useful to demonstrate the antimicrobial properties of pea protein-based bioplastics by adding nisin and make them suitable as potential candidates to replace conventional plastics in food packaging. © 2016 Society of Chemical Industry.

Sustainable Development Through Feedstock Recycling of Plastic Wastes

SummaryThe usage of plastic materials in daily life has continuously increased over the last 30 years. The amount of plastic consumed per inhabitant in the industrialized countries has increased by a factor of 60 over this period, while the generation of plastic wastes has grown at a similar rate. Recycling of plastic materials is now an important field in the plastics industry, not just an activity born under environmental pressure. The recycling processes include industrial operations in which secondary materials are reprocessed and/or monomers recovered for further polymerization; such processes are termed secondary and tertiary recycling. At present, there are three main alternatives for the management of plastic wastes in addition to land filling: (i) mechanical recycling by melting and regranulation of the used plastics, (ii) feedstock recycling and (iii) energy recovery. Consequently, feedstock recycling appears as a potentially interesting approach, based on the conversion of plastic wastes into valuable chemicals useful as fuels or as raw materials for the chemical industry. The cleavage and degradation of the polymer chains may be promoted by temperature, chemical agents, catalysts, etc. The purpose of this work is to describe and review the different alternatives developed for the feedstock recycling of plastic wastes, with emphasis on both the scientific and technical aspects.

Mapping of Agriculture Plastic Waste

The current intensification of the use of plastic materials in agriculture, although has increased significantly the productivity, is also generating growing adverse effects on the environment of the agro-ecosystem. The agriculture is responsible for a massive use of plastic materials, in addition to energy and water inputs, chemical fertilizer and pesticides. Besides the pollution generated during the manufacture, at the end of their lifetime plastic materials used for crop covering, soil mulching, packaging, containers, pots, irrigation and drainage pipes, may became a pollution source when improperly disposed, leaved on the ground or burned. Instead the agricultural plastic waste (APW), if correctly collected, can be used as a new secondary raw material or as an energy source. An adequate APW management can prevent economical losses and environmental damages. The territory of the Barletta, Andria, Trani Province (BAT), in the Apulia Region, South Italy, is an agricultural area characterized by vineyards, olive groves, orchards and vegetables; it represents an area of intense production of plastic wastes and with a widespread problem linked to the application of unacceptable disposal practices. The goal of this study is to define and quantify the different types of plastic waste produced by the agricultural practice in a restricted area of the municipal area of Trani and Barletta, to localize the points where the most remarkable quantities of them are generated, and to provide the local Authorities and the decision makers of a useful tool for implementing an efficient and effective waste management. A dedicated geo-referenced database was designed using land use maps in a GIS environment and applying a methodology that can be functional for any kind of agricultural plastic waste. The resulting database gives updated and complete information on the plastic waste generation, over the land, related to the cultivation kind.

Rowcovers and Strip Tillage Provide an Alternative to Plasticulture Systems in Summer Squash Production

Plastic mulch is often used in cucurbit production, but it has negative soil health and environmental implications due to use of tillage for installation and generation of plastic waste. This 2-year study aimed to find a viable alternative to plastic mulch through the use of strip tillage and rowcovers, as rowcovers could help minimize yield loss from strip tillage by providing warmer air and soil as well as providing insect protection. A split-plot design was used in both conventionally and organically managed summer squash (Cucurbita pepo), with production system as the whole-plot factor [conventional tillage with black plastic mulch also referred to as plasticulture (PL) and strip tillage into rolled cereal rye (Secale cereale) (ST)] and rowcover use as the subplot factor (rowcover until anthesis or no rowcover). Rowcovers reduced the incidence of squash vine borer (Melittia cucurbitae) and eliminated the need for insecticide sprays to control this insect pest, but did not reduce the incidence of yellow vine decline or the sprays needed to control squash bug (Anasa tristis). Rowcovers increased average air temperature by 1.6 to 4.0 °C and increased maximum air temperature by up to 10.3 °C. Rowcovers decreased average light intensity by 33% to 39%. Though soil temperature in PL tended to be higher than in ST, in 1-year rowcovers helped bridge the gap. Plant biomass was consistently higher in the PL than the ST system. Averaged across rowcover treatments, plants in PL had higher marketable yields than those in ST; however, the use of rowcovers often led to comparable yields between the production system treatments. Rowcover was a significant factor explaining marketable yield for the organically managed fields both years. There was no consistent effect of production system on soil microbial biomass carbon (MBC). Based on our results, strip tillage into rolled rye could be a viable alternative to plasticulture for summer squash production in Iowa, and rowcovers could help increase yields in ST especially in an organic management system.

Influence of shape and size of the particles on jigging separation of plastics mixture

Plastics are popular for numerous applications due to their high versatility and favourable properties such as endurance, lightness and cheapness. Therefore the generation of plastic waste is constantly increasing, becoming one of the larger categories in municipal solid waste.Almost all plastic materials are recyclable, but for the recycling to be possible it is necessary to separate the different types of plastics. The aim of this research was to evaluate the performance of the jig separation of bi-component plastic mixtures. For this study six granulated plastics had been used: Polystyrene (PS), Polymethyl methacrylate (PMMA), Polyethylene Terephthalate (PET-S, PET-D) and Polyvinyl Chloride (PVC-M, PVC-D).Plastics mixtures were subjected to jigging in a laboratorial Denver mineral jig. The results showed that the quality of the jigging separation varies with the mixture, the density differences and with the size and shape of the particles. In the case of particles with more regular shapes the quality of separation of bi-component plastic mixtures improved with the increase of the particle size. For lamellar particles the influence of particle size was minimal.In general, the beneficiation of plastics with similar densities was not effective, since the separation efficiency was lower than 25%. However, in bi-component plastic mixtures that join a low density plastic (PS) with a high density one (PMMA, PET-S, PET-D, PVC-M and PVC-D), the quality of the jigging separation was greatly improved. The PS grade in the sunk was less than 1% for all the plastic mixtures.Jigging proved to be an effective method for the separation of bi-component plastic mixtures. Jigging separation will be enhanced if the less dense plastic, that overflows, has a lamellar shape and if the denser plastic, that sinks, has a regular one.

Life Cycle Analysis on Regenerating and Energy Recovery of Plastic Solid Waste Management in Shanghai

Over the past several decades with significant technological advances there has been continuous increase in plastic manufacturing in China, which has contributed to the production of a great deal of plastics worldwide every year, and at the same time it has resulted in a large amount of plastic solid waste (PSW). It has great potential values for waste plastics to reuse as secondary materials, which may lessen pressure on resource and environment. The paper studies the status of waste plastics in recycling, reusing and reducing on management countering on the increase in the flow of waste plastics in Shanghai. In light of the methodology of life cycle, the study analyzes the environmental impacts associating with the alternatives in a ‘cradle to grave’ approve to PSW technological recycling systems. We will choose regenerating and energy recovery processes based on site investigation and literatures data in Shanghai to analyze recycling options and how various processes affect the environment. Life-cycle methodology was very suitable for evaluating the overall environmental consequences, and could be used for making decisions and planning strategies with the rapid increase of plastic solid waste generation for Shanghai.

폐플라스틱의 처리·재자원화 최신동향

Abstracts Large scale generation of plastic waste has generated considerable interest it seeking innovative solutions to waste recyclingand reuse. Plastic solid waste(PSW) treatment and recycling processes could be allocated to four major categories, re-extrusion(primary), mechanical recycling(secondary), chemical recycling(tertiary) and energy recovery(quaternary). This reviewconsiders the various aspects of the PSW recycling such as recycling methods of PSW, special problems about someproposed process, separation techniques, and recycling of mixed PSW. Key words : Plastic solid waste, Polyvinyl chloride, Depolymerization, Pyrolysis, Landfill, Gasification 1. 서 론 플라스틱은 풍화에 강하고 가벼우며, 다양한 1)색상으로착색이 가능하고 성형가공도 매우 용이하다. 또한 전기 절연성이 좋고 내산성과 내 알칼리성 등 내 부식성 기능도있어서 다양한 분야에서 다양한 용도로 활용되고 있다 . · Received : December 26, 2013 · 1st Revised : February 12, 2014 · 2nd Revised : April 22, 2014 · 3rd Revised : June 23, 2014 · Accepted : July 9, 2014Corresponding Author : Hee-Duck Shin (E-mail : hdshin5742@reseat.re.kr)Research Fellow Department, Korea Institute of Science and Technology Information, 66, Hoegi-ro, Dongdaemun-gu, Seoul130-741, KoreaTel : +82-2-3299-6231 / Fax : +82-2-3299-6234ⓒThe Korean Institute of Resources Recycling. All rights reserved. This is an open-access article distributed under the termsof the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permitsunrestricted non-commercial use, distribution and reproduction in any medium, provided the original work is properly cited.

Production patterns of packaging waste categories generated at typical Mediterranean residential building worksites

The construction sector is responsible for around 28% of the total waste volume generated in Europe, which exceeds the amount of household waste. This has led to an increase of different research studies focusing on construction waste quantification. However, within the research studies made, packaging waste has been analyzed to a limited extent. This article focuses on the packaging waste stream generated in the construction sector. To this purpose current on-site waste packaging management has been assessed by monitoring ten Mediterranean residential building works. The findings of the experimental data collection revealed that the incentive measures implemented by the construction company to improve on-site waste sorting failed to achieve the intended purpose, showing low segregation ratios. Subsequently, through an analytical study the generation patterns for packaging waste are established, leading to the identification of the prevailing kinds of packaging and the products responsible for their generation. Results indicate that plastic waste generation maintains a constant trend throughout the whole construction process, while cardboard becomes predominant towards the end of the construction works with switches and sockets from the electricity stage. Understanding the production patterns of packaging waste will be beneficial for adapting waste management strategies to the identified patterns for the specific nature of packaging waste within the context of construction worksites.

Review, mapping and analysis of the agricultural plastic waste generation and consolidation in Europe

A review of agricultural plastic waste generation and consolidation in Europe is presented. A detailed geographical mapping of the agricultural plastic use and waste generation in Europe was conducted focusing on areas of high concentration of agricultural plastics. Quantitative data and analysis of the agricultural plastic waste generation by category, geographical distribution and compositional range, and physical characteristics of the agricultural plastic waste per use and the temporal distribution of the waste generation are presented. Data were collected and cross-checked from a variety of sources, including European, national and regional services and organizations, local agronomists, retailers and farmers, importers and converters. Missing data were estimated indirectly based on the recorded cultivated areas and the characteristics of the agricultural plastics commonly used in the particular regions. The temporal distribution, the composition and physical characteristics of the agricultural plastic waste streams were mapped by category and by application. This study represents the first systematic effort to map and analyse agricultural plastic waste generation and consolidation in Europe.

Recycling of plastic packaging waste in Bandung City, Indonesia

Economic growth, changing consumption and production patterns are resulting in rapid increase in the generation of plastic wastes, including plastic packaging waste (PPW). A variety of PPW is identified in the municipal solid waste (MSW) stream. In this paper, quantity and composition of PPW at generators (residential and nonresidential sectors) and at the informal sector of waste recycling were measured, and accordingly the flow of PPW within Bandung City, Indonesia was analyzed. Though the generation rate per capita is not so high (25.1 g per day), total PPW generated by 2.3 million inhabitants in Bandung becomes 58.4 tonnes per day (3.76 % of total MSW generated). Due to lack of integrated MSW management, most of PPW is neither collected properly nor disposed of in appropriate manner by the municipality. Collection of valuable wastes including PPW is done predominantly by the informal sector without regard to health and safety. It is predicted that total PPW recycled by various informal waste recycling players like scavengers, junkmen, intermediates, and dealers is 27.5 tonnes per day (64.6 % of total PPW generated). Interviews regarding the existing handling methods and incentives preferred by generators to increase the recycling rate are also presented.

Chemical depolymerisation of PET complex waste: hydrolysis vs. glycolysis

The huge increase in the generation of post-consumer plastic waste has produced a growing interest in eco-efficient strategies and technologies for their appropriate management and recycling. In response to this, PROQUIPOL Project is focused on developing, optimizing and adapting feedstock recycling technologies as an alternative for management for the treatment of complex plastic waste. Among the different plastic wastes studied, PROQUIPOL Project is working on providing a suitable treatment to the highly colored and complex multilayered post-consumer waste fractions of polyethylene terephthalate (PET) by chemical depolymerisation methods. Glycolysis and alkali hydrolysis processes have been studied with the aim of promoting the transformation of PET into the bis(2-hydroxyethyl) terephthalate monomer and terephthalic acid, respectively. In both cases operational conditions such as temperature, reaction time, catalyst to PET rate and solvent to PET rate have been considered to optimize product yield, achieving values near to 90 % and monomer purities over 95 % in both processes. This paper presents results obtained for each treatment as well as a simplified comparison of technical, economic and environmental issues.

Scenarios simulation on municipal plastic waste generation of different functional areas of Beijing

With the rapid economic development of China and the improvement of people’s living standards, municipal plastic waste (MPW) has increasingly become a major problem for cities in China. The generation of plastic waste is a system which integrates social, economical and environment factors. There is a certain guiding significance for the determination of urban plastic waste management priorities to research MPW generation with the background of the regional development of the city. As the capital of China, Beijing develops with a typically regional characteristic. This article establishes a generation system model for MPW by the method of system dynamics, and takes Beijing as an example to simulate and forecast the MPW generations of four functional areas on scenarios. The data used in the model were mainly obtained from statistical materials and on-site survey. The results showed a better regulating effect of the generation of MPW of Beijing under an integrated control scenario. In terms of space, MPW generation of the urban function extended districts generated the largest amount of plastic waste, with the largest growth rate; the proportion of MPW generation of the new districts of urban development increased significantly. In terms of generation source, the resident communities source generated the largest amount of the MPW. Based on the results, some suggestions on MPW management are put forward.

Impact of family income and size on per capita solid waste generation: A case study in Manmunai North Divisional Secretariat Division of Batticaloa

The generation of solid waste has become an increasing environmental and public health problem everywhere in the world, especially in developing countries. The rate of generation of solid waste in the society is increasing with an increase of population, technological development, and the changes in the life styles of the people. As family size and income are the most significant factors affecting the quantity of solid waste from household consumption, a study on the relationship among these is vital in the decision making on waste management strategies. Therefore, a study was conducted at Manmunai North Divisional Secretariat areas of Batticaloa district to find out the correlation among residential solid waste generation, family size and income. The household sector is one of the primary sources of solid wastes in the study area. This study covered 100 houses with different socioeconomic levels such as income level and family size. There were six components of solid waste; food waste, paper, polyethylene, plastic, glass and metal which were evaluated in this study.Present study revealed that residential solid waste generation showed non-significant positive correlation (r = 0.184, p>0.05) with monthly income whereas significant positive correlation (r = 0.476, p<0.01) was found with the family size. Based on monthly income, generation of food, paper, plastic and glass waste showed non-significant positive correlation while non-significant negative correlation was found with polyethylene waste. Further, residential waste generation such as food, paper, plastic and metal showed significant positive correlation with family size whereas generation of glass and polyethylene waste showed non-significant positive correlation with family size.Keywords: Family size, Food waste, Income level, Plastics, Solid wasteDOI: http://dx.doi.org/10.4038/josuk.v5i0.4087 J Sci.Univ.Kelaniya 5 (2010): 13-23

Studies on biodegradation of LDPE film in the presence of potential bacterial consortia enriched soil

Low density polyethylene (LDPE) is an important commodity plastic and has a wide applicability in the modern era. In virtue of their wide applicability, the generation of the huge plastic waste became a conundrum for environment and public health. Consequently, the present study was conducted for the microbial degradation of LDPE film in natural conditions using mixture of potential polymer degrading consortia. For this purpose, the talc based formulation of bacterial consortia was inoculated into soil with LDPE film for the period of three months. Fourier transform infrared spectroscopy (FT–IR) in combination with SEM revealed that the consortia incurred significant surfacial degradation of LDPE film, introduction of hydroxyl (–OH) functionality and significant shifts in fingerprint region, respectively. The potential of the consortia towards degradation of LDPE has further been ascertained through change in bulk structural characteristics using differential scanning calorimetry (DSC). Moreover, the comparative in situ biodegradation study of LDPE film in laboratory and natural conditions indicates that environmental factors like sun-light, temperature and rainfall may enhance the rate of biodegradation of the polymer in nature.

Waste Polyolefins to Liquid Fuels via Pyrolysis: Review of Commercial State-of-the-Art and Recent Laboratory Research

With generation of waste plastics increasing, current EU legislation dictates high recovery rates and policy favours waste management technology choices that occupy a high position on the waste management hierarchy. Pyrolysis is a thermochemical conversion technology that can be considered a ‘feedstock recycling’ process and may play an increasing role in integrated waste management systems of the future. The objective of this article is to present a review of current state-of-the-art commercial pyrolysis processes for the production of liquid transport fuels from waste polyolefins (polyethylenes and polypropylenes). Current plastic waste generation and management practices are briefly summarised. Waste management infrastructure in Europe is reliant on landfill, incineration and mechanical recycling, while feedstock recycling plays an insignificant role. Plastic-to-liquid platforms including delocalised pyrolysis followed by centralised upgrading, stand alone facilities, and integrated waste management infrastructure concepts are briefly discussed. Commercial operations and their process configurations are compared. Reactor technology for cracking of plastic waste is presented. Important issues like fuel quality and contamination are also discussed. Fuel finishing operations and fuel additives required to achieve an engine ready fuel are described in the final section. Recently published laboratory research in thermal and catalytic pyrolysis and integrated and co-processing studies are also summarised in this review.

Household solid waste generation and characteristic in a Mekong Delta city, Vietnam

This study was undertaken to evaluate the quantity and composition of household solid waste to identify opportunities for waste recycling in Can Tho city, the capital city of the Mekong Delta region in southern Vietnam. Two-stage survey of 100 households was conducted for dry season and rainy season in 2009. Household solid waste was collected from each household and classified into 10 physical categories and 83 subcategories. The average household solid waste generation rate was 285.28 g per capita per day. The compostable and recyclable shares respectively accounted for 80.02% and 11.73%. The authors also analyzed the relations between some socioeconomic factors and household solid waste generation rates by physical categories and subcategories. The household solid waste generation rate per capita per day was positively correlated with the population density and urbanization level, although it was negatively correlated with the household size. The authors also developed mathematical models of correlations between the waste generation rates of main physical categories and relevant factors, such as household size and household income. The models were proposed by linear models with three variables to predict household solid waste generation of total waste, food waste, and plastic waste. It was shown that these correlations were weak and a relationship among variables existed. Comparisons of waste generation by physical compositions associated with different factors, such as seasonal and daily variation were conducted. Results presented that the significant average differences were found by the different seasons and by the different days in a week; although these correlations were weak. The greenhouse gas baseline emission was also calculated as 292.25 g (CO 2 eq.) per capita per day from biodegradable components.

Assessment of plastic waste generation and its potential recycling of household solid waste in Can Tho City, Vietnam

Plastic solid waste has become a serious problem when considering the disposal alternatives following the sequential hierarchy of sound solid waste management. This study was undertaken to assess the quantity and composition of household solid waste, especially plastic waste to identify opportunities for waste recycling. A 1-month survey of 130 households was carried out in Can Tho City, the capital city of the Mekong Delta region in southern Vietnam. Household solid waste was collected from each household and classified into ten physical categories; especially plastic waste was sorted into 22 subcategories. The average household solid waste generation rate was 281.27g/cap/day. The compostable and recyclable shares respectively accounted for high percentage as 80.74% and 11%. Regarding plastic waste, the average plastic waste generation rate was 17.24g/cap/day; plastic packaging and plastic containers dominated with the high percentage, 95.64% of plastic waste. Plastic shopping bags were especially identified as the major component, accounting for 45.72% of total plastic waste. Relevant factors such as household income and household size were found to have an existing correlation to plastic waste generation in detailed composition. The household habits and behaviors of plastic waste discharge and the aspects of environmental impacts and resource consumption for plastic waste disposal alternatives were also evaluated.