scholarly journals Composition of Plastic Fractions in Waste Streams: Toward More Efficient Recycling and Utilization

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 69 ◽  
Author(s):  
Ville Lahtela ◽  
Marko Hyvärinen ◽  
Timo Kärki

Reuse of materials is a significant global goal that contributes to sustainable development. Polymer-specific plastic identification from the waste stream is examined in this study to achieve environmentally optimistic reuse of plastic material in secondary applications. Two diverse waste streams, 86.11 kg of construction and demolition waste (CDW) plastic and 57.74 kg of mechanically sorted plastic, were analyzed by using a handheld tool whose identification technology was based on the near-infrared spectrum. The study indicates a significant effect of human and single fraction on manual separation. The polymer composition in the plastic waste stream varied depending on the source, but the most common plastic grades, polypropylene (PP) and polyethylene (PE), were represented in every waste stream. The waste stream also included unidentified and unfavorable wastes, which indicates that identification of the plastic fractions is needed and more studies should be done in this field in the future.

2018 ◽  
Vol 8 (1) ◽  
pp. 8
Author(s):  
Nadia Qamar ◽  
Ayesha Alam Khurram

In Pakistan, construction and demolition waste(CDW) is generated in voluminous amount each year. CDW iswidely ill-handled and ultimately fed to landfills causing harm tothe already alarming environmental conditions. In order tosearch for the solution of this drastic matter, a study was done,which is explained in this paper. This paper presents the studydone at a demolition site near Karachi, in Sindh while thedemolition works were being carried out. At the site there wereold barracks which were being demolished. Before the demolitionworks were commenced, the site was surveyed and structuralcomponents of the barracks were counted and their dimensionswere measured. When the demolition was over, the demolishedwaste was calculated which comprised of concrete and masonryrubble, steel round bars, steel doors, steel windows, steel ceiling,steel girders, steel main gate, and plastic water tank. This studyinterpreted that construction and demolition (C&D) works wereprogressing considering the works’ deadline and the clients’requirements but the ecosystem’s ecology and the environmentalhealth were not taken into account. Recommendations are madeto handle CDW properly throughout its lifecycle. Theserecommendations aim to provide technological and logicalsolutions to grip CDW. The recommendations include wastereduction and reusing waste, life cycle assessment and costing,environmental and economic impact, material flow analysis, andadvanced computerized-tools.


Author(s):  
Eleftherios Eleftheriou ◽  
Elia A. Tantele ◽  
Renos A. Votsis ◽  
Eleni Charilaou

Waste is an area regulated by a large number of legislations at both international and European Union level. Building waste was recognized as a special waste stream in the 1990s and identified as a priority waste stream. This recognition for this waste stream was necessary because of the large proportion of this waste in proportion to the total amount of waste, but also the huge potential for reuse and recycling contained. The term used in Cyprus Legislation is Excavation, Construction and Demolition Waste, which includes waste from the construction and civil engineering works, and of natural and technological disasters. The aforementioned waste is also produced by the demolition of existing buildings as well as from renovation and maintenance work. They contain various ingredients-hazardous or not, and problems arise when their management doesn’t take into account the protection of the environment and public health. This paper deals with the management of Construction and Demolition Waste considering the Cycle economy, with a special focus on Cyprus, as well as the analysis of the existing strategy and policy on the national level. On this basis, solutions are proposed, and recommendations are noted where needed as to revising, updating and strengthening the existing policy.


2020 ◽  
Vol 38 (9) ◽  
pp. 923-941
Author(s):  
Melanie Rašković ◽  
Arne M Ragossnig ◽  
Krzysztof Kondracki ◽  
Michaela Ragossnig-Angst

Waste from the construction sector poses huge challenges for sustainable waste management. This is not only due to the vast amount of waste produced in construction and demolition activities, but also due to pollutants potentially contained in these products. Subject to these conditions, waste management must ensure recovery of as many resources as possible, while making sure to keep material loops clean. This demanding task requires more knowledge about the existing building stock and an adaptation of current demolition processes. Innovative technologies, such as Building Information Modelling, or modern frameworks, such as Geographic Information Systems, offer a high potential to synoptically provide stock material information for future demolition activities for individual objects to be deconstructed as well as for whole cities as a basis for managing the anthropogenic stock and potential urban mining. Suitable methods of data collection allow for acquiring the desired input for the generation of building stock models enriched with demolition-related information. With the latter, selective deconstruction strategies as well as appropriate waste stream routing agendas can be planned and executed, thereby securing safety at work during the demolition process itself and a waste stream routing according to the waste hierarchy. This review article gives an overview of currently deployed building material assessment tools (data capture and visualisation), both a prerequisite for improved information on materials and geometry (and thereby mass/volume). In addition, this article describes workflows employable for the purpose of urban mining in end-of-life buildings, of which one holistic approach will be described in depth.


2018 ◽  
Vol 1 (1) ◽  
pp. 8
Author(s):  
Nadia Qamar ◽  
Ayesha Alam Khurram

In Pakistan, construction and demolition waste(CDW) is generated in voluminous amount each year. CDW iswidely ill-handled and ultimately fed to landfills causing harm tothe already alarming environmental conditions. In order tosearch for the solution of this drastic matter, a study was done,which is explained in this paper. This paper presents the studydone at a demolition site near Karachi, in Sindh while thedemolition works were being carried out. At the site there wereold barracks which were being demolished. Before the demolitionworks were commenced, the site was surveyed and structuralcomponents of the barracks were counted and their dimensionswere measured. When the demolition was over, the demolishedwaste was calculated which comprised of concrete and masonryrubble, steel round bars, steel doors, steel windows, steel ceiling,steel girders, steel main gate, and plastic water tank. This studyinterpreted that construction and demolition (C&D) works wereprogressing considering the works’ deadline and the clients’requirements but the ecosystem’s ecology and the environmentalhealth were not taken into account. Recommendations are madeto handle CDW properly throughout its lifecycle. Theserecommendations aim to provide technological and logicalsolutions to grip CDW. The recommendations include wastereduction and reusing waste, life cycle assessment and costing,environmental and economic impact, material flow analysis, andadvanced computerized-tools.


2015 ◽  
Vol 5 (2) ◽  
pp. 81-86
Author(s):  
Irina Smical ◽  
F. Filip-Văcărescu ◽  
G. Danku ◽  
V. Paşca

Abstract The recycling issues related to the construction and demolition (C&D) wastes in the sustainable development and the circular economy context represent a continuous challenge for researchers. This paper reveals the possibility to recycle the hardened mortar recovered from C&D wastes. Thus, the recovered hardened mortar with grains size less than 16 mm was used in the concrete structure. The compression resistance of the final concrete was determined using a Heckert 3000 KN testing machine and the results showed a better compressive strength for the samples with C&D waste content than the standard sample of about 1.19 times. This is a good premise for improving the researches related to C&D waste usage in concrete production.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Maryam Eghbali-Zarch ◽  
Reza Tavakkoli-Moghaddam ◽  
Kazem Dehghan-Sanej ◽  
Amin Kaboli

PurposeThe construction industry is a key driver of economic growth. However, the adverse impacts of construction and demolition waste (CDW) resulted from the active construction projects on the economy, environment, public health and social life necessitates an appropriate control and management of this waste stream. Developing and promoting the construction and demolition waste management (CDWM) hierarchy program at the strategic level is essential.Design/methodology/approachThis study aims to propose a hybrid decision model that hybridizes the Integrated Determination of Objective Criteria Weights (IDOCRIW) and weighted aggregated sum product assessment (WASPAS) under a fuzzy environment.FindingsThe proposed method ranks the potential strategic alternatives by the sustainable development criteria to improve the performance of CDWM. As indicated in the results, the fuzzy approach in the decision-making process enables the transformation of linguistic variables into fuzzy numbers that show uncertainty and ambiguity in real-world systems. Moreover, the close correlation between the final ranking of the proposed methodology and the average priority order of the strategic alternatives obtained by five different multi-criteria decision-making (MCDM) methods implies the validity of the model performance.Practical implicationsThis proposed model is an appropriate tool to effectively decide on the development of CDWM from a strategic point of view. It aims to establish an MCDM framework for the evaluation of effective strategies for CDWM according to the indices of sustainable development. Implementing proper operational plans and conducting research in CDWM has the highest priority, and enacting new and more stringent laws, rules and regulations against the production of CDW has secondary priority. This study contributes to the field by optimizing the CDWM by applying the top-priority strategies resulted from the proposed fuzzy hybrid MCDM methodology by the decision-makers or policy-makers to reach the best managerial strategic plan.Originality/valueIn the proposed methodology, the IDOCRIW technique is utilized and updated with the triangular fuzzy numbers for the first time in the literature to derive the weights of sustainable development criteria. The fuzzy WASPAS method is utilized for evaluation and providing a final ranking of the strategic alternatives.


Author(s):  
Alice Bernard Benshak ◽  

The continuous rise in population, urbanization and expansion of cities has triggered a corresponding increase in construction and demolition activity. The frequent collapse of buildings attributed to poor structural design, building decay, and/or use of substandard materials has generated a substantial increase in construction refuse, also referred to as Construction and Demolition (C&D) Waste. This waste stream originates from residential, commercial, agricultural, institutional and industrial building projects for new builds, reconstruction, expansion, and refurbishments/rehabilitation. Most studies in Nigeria have generally focused on solid waste management without considering the uniqueness of C&D and giving it the attention needed, in order to achieve sustainable urban spaces that are highly functional, safe, convenient, and livable. This study seeks to investigate the different approaches and processes of C&D waste management in the City of Jos, in the Plateau State of Nigeria. The mix method was adopted for this research whereby quantitative and qualitative data was collected through a structured questionnaire for construction enterprises, as well as face-to-face interviews with the agencies responsible for waste management in the city. A total of 21 construction companies (representing about 10%) were randomly selected for questionnaire administration while interviews were conducted with the Plateau Environmental Protection and Sanitation Agency (PEPSA) and the Jos Metropolitan Development Board (JMDB) who are responsible for waste management. Investigations revealed that C&D waste consists of heavy and non-degradable materials such as: sheet metal roofing, sand, gravel, concrete, masonry, metal, and wood to mention only a few. The construction companies are solely responsible for: the collection, storage, transportation and disposal of wastes generated from their activities. Approximately 60-70% of the C&D waste materials are either reused, recycled or resold, while the remaining residual waste is indiscriminately disposed. Although the PEPSA and JMDB are responsible for waste management, their focus has been on establishing solid non-hazardous waste infrastructure systems, policies and plans. The absence of records of the quantity of C&D waste generated, the lack of financial data, and the omission of policies and plans for the C&D waste stream has resulted in a missed opportunity for a comprehensive and sustainable waste management strategy for the City and the state. To protect public health, valuable resources, and natural ecosystems, it is recommended that the C&D waste stream be included as part of the state’s waste management program, in consideration of the growing construction and demolition activity, by including C&D policies and guidelines.


Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3887 ◽  
Author(s):  
Santiago Yagüe García ◽  
Cristina González Gaya

Numerous waste streams can be employed in different cement production processes, and the inclusion of pozzolans will, moreover, permit the manufacture of concrete with improved hydraulic properties. Pozzolanic materials can be added to Ordinary Portland Cement (OPC) in the range of 10%–20% by mass of cement. One such example is the phyllosilicate kaolinite (K), and its calcined derivative metakaolin (MK), incorporated in international cement manufacturing standards, due to its high reactivity and utility as a pozzolan. In the present paper, discarded ballast classed as Construction and Demolition Waste (C&DW) is reused as a pozzolanic material. Various techniques are used to characterize its chemical, mineralogical, and morphological properties, alongside its mechanical properties, such as compressive and flexural strength. Discarded ballast in substitution of cement at levels of 10% and 20% produced type II or IV pozzolanic cements that yielded satisfactory test results.


Author(s):  
Kaushik Bokarde

Abstract: Construction activity in India has magnified well within the past decade. Likewise, there has conjointly been a proportion to rise within the generation of construction and demolition waste (C&DW). This, alongside the fact that in India the speed of recycling and reuse of C&DW continues to be quite low and has engendered a heavy environmental downside and a motivation to develop ways and management plans to resolve it. Almost every time the construction and demolition waste end up settling in landfills disrupting the environmental, economic, and social life cycle. Its composition has a significant potential to reuse or recycle C&DW, and thereby, contribute to enhancing the sustainability of construction, however, practical procedures don’t seem to be widely known or practiced within the construction industry. Elements of construction and demolition waste generally embrace concrete, asphalt, wood, metals, roofing, paper, plastic, drywall, and glass. Sustainable development defines as accomplishing the current requirements without compromising the ability of future generations to satisfy their own needs and can be thought of as one of the concrete solutions to resolve construction and demolition waste downside. Sustainable development in construction can facilitate plenty to cut back the issues associated with the environment and natural resources as the construction industry is among the major user of the world’s resources. Sustainable design, correct use, and reuse of the resources/construction materials can create the construction industry a lot more economical and greener. There’s conjointly a large demand for natural aggregates within the construction sector with a big gap in its demand and supply, which may even be reduced marginally by the employment of recycling and reuse of construction and demolition waste. Correct handling, storage, and treatment of C&D waste not only solely forestall degradation of Mother Earth but even have an important impact on sustainability using reducing the usage of natural resources. The paper covers various issues associated with the reusing and recycling of C&D waste, which needs restrictive mechanisms and procedures to be followed for achieving the aim of sustainability in the construction industry.


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