scholarly journals Chemical and Leaching Behavior of Construction and Demolition Wastes and Recycled Aggregates

2020 ◽  
Vol 12 (24) ◽  
pp. 10326
Author(s):  
Alessandra Diotti ◽  
Adela Perèz Galvin ◽  
Andrea Piccinali ◽  
Giovanni Plizzari ◽  
Sabrina Sorlini
Keyword(s):  
Environmental Performance ◽  
Raw Materials ◽  
Recycled Aggregates ◽  
Critical Parameters ◽  
Leaching Behavior ◽  
Sustainable Building ◽  
Regulatory Limits ◽  
Construction And Demolition Wastes ◽  
Construction Products ◽  
The Eu

Construction and demolition wastes are widely recognized as the main waste stream in the EU, and their recycling and recovery is an important issue in sustainable building industry development. The composition of construction and demolition wastes is highly heterogeneous and is influenced by several factors, including the raw materials and construction products used. The environmental performance of these materials are therefore considerably variable and, in some cases, do not comply with the regulatory limits established to ensure the protection of the natural environment. In this context, this paper presents a data analysis on the environmental behavior of construction and demolition wastes and recycled aggregates in terms of both chemical composition and the release of contaminants according to a leaching test. Subsequently, the most critical parameters for recovery were identified and statistically evaluated. The leaching results showed that SO4, Cu, and COD are critical compounds for both CDWs and RAs.

scholarly journals Leaching Behaviour of Construction and Demolition Wastes and Recycled Aggregates: Statistical Analysis Applied to the Release of Contaminants

2021 ◽  
Vol 11 (14) ◽  
pp. 6265
Author(s):  
Alessandra Diotti ◽  
Giovanni Plizzari ◽  
Sabrina Sorlini
Keyword(s):  
Particle Size ◽  
Statistical Analysis ◽  
Raw Materials ◽  
Primary Source ◽  
Recycled Aggregates ◽  
Critical Parameters ◽  
Material Particle ◽  
Analysis Methodology ◽  
Construction And Demolition Wastes ◽  
Leaching Behaviour

Construction and demolition wastes represent a primary source of new alternative materials which, if properly recovered, can be used to replace virgin raw materials partially or totally. The distrust of end-users in the use of recycled aggregates is mainly due to the environmental performance of these materials. In particular, the release of pollutants into the surrounding environment appears to be the aspect of greatest concern. This is because these materials are characterized by a strong heterogeneity which can sometimes lead to contaminant releases above the legal limits for recovery. In this context, an analysis of the leaching behaviour of both CDWs and RAs was conducted by applying a statistical analysis methodology. Subsequently, to evaluate the influence of the particle size and the volumetric reduction of the material on the release of contaminants, several experimental leaching tests were carried out according to the UNI EN 12457-2 and UNI EN 12457-4 standards. The results obtained show that chromium, mercury, and COD are the most critical parameters for both CDWs and RAs. Moreover, the material particle size generally affects the release of contaminants (i.e., finer particles showed higher releases), while the crushing process does not always involve higher releases than the sieving process.

scholarly journals Experimental study and modeling of the mechanical behavior of recycled aggregates-based high-strength concrete

2021 ◽  
Vol 15 (56) ◽  
pp. 203-216
Author(s):  
Kheira Camellia Nehar ◽  
Dalila Benamara
Keyword(s):  
Sustainable Development ◽  
High Strength Concrete ◽  
High Efficiency ◽  
Raw Materials ◽  
High Strength ◽  
Recycled Aggregates ◽  
Concrete Aggregates ◽  
Strength Concrete ◽  
Construction And Demolition Wastes ◽  
Natural Aggregates

Concrete, a material of prime importance, is widely used in various works. Among the raw materials composing concrete, aggregates come first. It is widely acknowledged that the consumption of natural aggregates increases with the growth in the amount of concrete needed. It has recently emerged that concrete waste can be recycled and reused in civil engineering works after a series of treatments. Moreover, in order to protect the environment and based on the principles of sustainable development, it was considered urgent to produce a High Strength Concrete incorporating recycled materials in addition to silica fume and a high-efficiency superplasticizer. This would certainly help to establish a harmonious sustainable development that guaranties the ecological balance and environmental protection, and prevents the depletion of natural resources. This study is part of a larger research program that that seeks to recover, recycle and valorize construction and demolition wastes. The main objective sought in this article is firstly to use aggregates from demolition concrete in the manufacture of a new concrete with high mechanical and rheological performance, and secondly, to model the behavior of this type of concrete using the Finite Element Method. This modeling aims to evaluate the maximum compressive strengths and compare them with those obtained experimentally.

European experience in transition to circular economy

2020 ◽  
Vol 19 (4) ◽  
pp. 598-617 ◽  
Author(s):  
S.V. Ratner
Keyword(s):  
European Union ◽  
Circular Economy ◽  
Raw Materials ◽  
Action Plan ◽  
National Level ◽  
The European Union ◽  
Scientific Methods ◽  
European Experience ◽  
General Scientific ◽  
The Eu

Subject. The article considers the concept of circular economy, which has originated relatively recently in the academic literature, and is now increasingly recognized in many countries at the national level. In the European Union, the transition to circular economy is viewed as an opportunity to improve competitiveness of the European Union, protect businesses from resource shortages and fluctuating prices for raw materials and supplies, and a way to increase employment and innovation. Objectives. The aim of the study is to analyze the incentives developed by the European Commission for moving to circular economy, and to assess their effectiveness on the basis of statistical analysis. Methods. I employ general scientific methods of research. Results. The analysis of the EU Action Plan for the Circular Economy enabled to conclude that the results of the recent research in circular economy barriers, eco-innovation, technology and infrastructure were successfully integrated into the framework of this document. Understanding the root causes holding back the circular economy development and the balanced combination of economic and administrative incentives strengthened the Action Plan, and it contributed to the circular economy development in the EU. Conclusions. The measures to stimulate the development of the circular economy proposed in the European Action Plan can be viewed as a prototype for designing similar strategies in other countries, including Russia. Meanwhile, a more detailed analysis of barriers to the circular economy at the level of individual countries and regions is needed.

scholarly journals Potential Benefits and Constraints of Development of Critical Raw Materials’ Production in the EU: Analysis of Selected Case Studies

Resources ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 67
Author(s):  
Katarzyna Guzik ◽  
Krzysztof Galos ◽  
Alicja Kot-Niewiadomska ◽  
Toni Eerola ◽  
Pasi Eilu ◽  
...  
Keyword(s):  
Case Studies ◽  
Social Acceptance ◽  
Raw Materials ◽  
Local Level ◽  
Ore Deposits ◽  
Abandoned Mines ◽  
Social Constraints ◽  
Cost And Benefit Analysis ◽  
The Eu ◽  
Critical Raw Materials

Major benefits and constraints related to mineral extraction within the EU have been identified on the examples of selected critical raw materials’ deposits. Analyzed case studies include the following ore deposits: Myszków Mo-W-Cu (Poland), Juomasuo Au-Co (Finland), S. Pedro das Águias W-Sn (Portugal), Penouta Nb-Ta-Sn (Spain), Norra Kärr REEs (Sweden) and Trælen graphite (Norway). They represent different stages of development, from the early/grassroot exploration stage, through advanced exploration and active mining, up to reopening of abandoned mines, and refer to different problems and constraints related to the possibility of exploitation commencement. The multi-criteria analysis of the cases has included geological and economic factors as well as environmental, land use, social acceptance and infrastructure factors. These factors, in terms of cost and benefit analysis, have been considered at three levels: local, country and EU levels. The analyzed cases indicated the major obstacles that occur in different stages of deposit development and need to be overcome in order to enable a new deposit exploitation commencement. These are environmental (Juomasuo and Myszków), spatial (Juomasuo) as well as social constraints (Norra Kärr, Juomasuo). In the analyzed cases, the most important constraints related to future deposit extraction occur primarily at a local level, while some important benefits are identified mainly at the country and the EU levels. These major benefits are related to securing long-term supplies for the national industries and strategically important EU industry sectors.

scholarly journals Application of Construction and Demolition Waste in Civil Construction in the Brazilian Amazon—Case Study of the City of Rio Branco

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2247
Author(s):  
Fernando da Silva Souza ◽  
José Maria Franco de Carvalho ◽  
Gabriela Grotti Silveira ◽  
Vitória Cordeiro Araújo ◽  
Ricardo André Fiorotti Peixoto
Keyword(s):  
Mechanical Strength ◽  
Raw Materials ◽  
Amazon Region ◽  
Construction And Demolition Waste ◽  
Recycled Aggregates ◽  
Federal State ◽  
Construction Sites ◽  
Demolition Waste ◽  
Conventional Concrete ◽  
Initial Adhesion

The lack of usable aggregates for civil construction in Rio Branco (capital of Acre, a Federal State in the Amazon region) makes the production and use of recycled aggregates from construction and demolition waste (CDW) an alternative of great interest. In this study, a comprehensive characterization of CDW collected from 24 construction sites of six building types and three different construction phases (structures, masonry, and finishing) was carried out. The fine and coarse recycled aggregates were produced and evaluated in 10 different compositions. The aggregates’ performance was evaluated in four mixtures designed for laying and coating mortars with a total replacement of conventional aggregates and a mixture designed for a C25 concrete with 50% and 100% replacement of conventional aggregates. CDW mortars showed lower densities and greater water retention, initial adhesion, and mechanical strength than conventional mortars. CDW concretes presented lower densities and greater resistance to chloride penetration than conventional concrete, with a small mechanical strength reduction. The recycled CDW aggregates proved to be technologically feasible for safe application in mortars and concrete; for this reason, it is believed that the alternative and proposed methodology is of great interest to the Amazonian construction industry, considering the high costs of raw materials and the need for defining and consolidating a sustainable development model for the Amazon region.

scholarly journals How Far Away Are World Economies from Circularity: Assessing the Capacity of Circular Economy Policy Packages in the Operation of Raw Materials and Industrial Wastes

2021 ◽  
Vol 13 (8) ◽  
pp. 4394
Author(s):  
Margarita Ignatyeva ◽  
Vera Yurak ◽  
Alexey Dushin ◽  
Vladimir Strovsky ◽  
Sergey Zavyalov ◽  
...  
Keyword(s):  
The Netherlands ◽  
Waste Management ◽  
South Korea ◽  
Circular Economy ◽  
Raw Materials ◽  
Industrial Wastes ◽  
New Guidelines ◽  
The 1960S ◽  
Degree Level ◽  
The Eu

Nowadays, circular economy (CE) is on the agenda, however, this concept of closed supply chains originated in the 1960s. The current growing quantity of studies in this area accounts for different discourses except the holistic one, which mixes both approaches—contextual and operating (contextual approach utilizes the thorough examination of the CE theory, stricture of the policy, etc.; the operating one uses any kind of statistical data)—to assess the capacity of circular economy regulatory policy packages (CERPP) in operating raw materials and industrial wastes. This article demonstrates new guidelines for assessing the degree level of capacity (DLC) of CERPPs in the operation of raw materials and industrial wastes by utilizing the apparatus of the fuzzy set theory. It scrupulously surveys current CERPPs in three regions: the EU overall, Finland and Russia; and assesses for eight regions—the EU overall, Finland, Russia, China, Greece, France, the Netherlands and South Korea—the DLC of CERPPs in operating raw materials and industrial wastes. The results show that EU is the best in CE policy and its CERPP is 3R. The following are South Korea and China with the same type of CERPP. Finland, France and the Netherlands have worse results than EU with the type of CERPP called “integrated waste management” because of the absence of a waste hierarchy (reduce, recover, recycle). Russia closes the list with the type of CERPP “basic waste management”.

scholarly journals Characterisation and Life Cycle Assessment of Pervious Concrete with Recycled Concrete Aggregates

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 209
Author(s):  
Adilson C. Paula Junior ◽  
Cláudia Jacinto ◽  
Thaís M. Oliveira ◽  
Antonio E. Polisseni ◽  
Fabio M. Brum ◽  
...  
Keyword(s):  
Environmental Performance ◽  
Treatment Plant ◽  
Recycled Concrete ◽  
Pervious Concrete ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Positive Contribution ◽  
Concrete Aggregates ◽  
Recycled Concrete Aggregates

The search for environmental preservation and conservation of natural resources gives rise to new concepts and viable technical solutions on the path to sustainable development. In this context, this study’s main objective is to analyse the influence of recycled concrete aggregates (RCAs) on the development of pervious concrete, whose use as a floor covering represents an excellent device to mitigate the urban soil sealing phenomena. For this, mechanical and hydraulic tests were carried out, in addition to microstructural analyses and the assessment of its environmental performance. The results obtained were compared to reference studies also involving the incorporation of recycled aggregates. A pilot-scale case study was conducted, involving a parking space lined with pervious concrete moulded “in situ”. In laboratory tests, permeability coefficients and mechanical strengths compatible with the literature and above the normative limit for light traffic were found. The case study demonstrated higher permeability than in the laboratory, but the flexural strength was lower, being indicated only for pedestrian traffic. The environmental assessment showed that the RCA represents a positive contribution to the environmental performance of pervious concrete. Still, attention should be given to the recycled aggregate transport distance between the concrete plant and the RCA treatment plant.

scholarly journals Mineralogy and Geochemistry of Ultramafic Rocks from Rachoni Magnesite Mine, Gerakini (Chalkidiki, Northern Greece)

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 934
Author(s):  
Evangelos Tzamos ◽  
Micol Bussolesi ◽  
Giovanni Grieco ◽  
Pietro Marescotti ◽  
Laura Crispini ◽  
...  
Keyword(s):  
Raw Materials ◽  
Mining Area ◽  
Ultramafic Rocks ◽  
Northern Greece ◽  
Icp Ms ◽  
Time In Literature ◽  
History Of ◽  
First Time ◽  
The Eu

The importance of magnesite for the EU economy and industry is very high, making the understanding of their genesis for the exploration for new deposits a priority for the raw materials scientific community. In this direction, the study of the magnesite-hosting ultramafic rocks can be proved very useful. For the present study, ultramafic rock samples were collected from the magnesite ore-hosting ophiolite of the Gerakini mining area (Chalkidiki, Greece) to investigate the consecutive alteration events of the rocks which led to the metallogenesis of the significant magnesite ores of the area. All samples were subjected to a series of analytical methods for the determination of their mineralogical and geochemical characteristics: optical microscopy, XRD, SEM, EMPA, ICP–MS/OES and CIPW normalization. The results of these analyses revealed that the ultramafic rocks of the area have not only all been subjected to serpentinization, but these rocks have also undergone carbonation, silification and clay alteration. The latter events are attributed to the circulation of CO2-rich fluids responsible for the formation of the magnesite ores and locally, the further alteration of the serpentinites into listvenites. The current mineralogy of these rocks was found to be linked to one or more alteration event that took place, thus a significant contribution to the metallo- and petrogenetic history of the Gerakini ophiolite has been made. Furthermore, for the first time in literature, Fe inclusions in olivines from Greece were reported.

The international strength of the euro will grow

2021 ◽  
Keyword(s):  
Euro Area ◽  
Financial Services ◽  
Raw Materials ◽  
Domestic Demand ◽  
Content Type ◽  
The Us ◽  
Us Dollar ◽  
Strategic Autonomy ◽  
Geopolitical Risks ◽  
The Eu

Significance The proposals identified areas where the euro could potentially become more dominant, such as the issuance of green bonds, digital currencies, and international trade in raw materials and energy. Ambitions to enhance the international leverage of the euro are being driven by the aim to strengthen EU strategic autonomy amid rising geopolitical risks. Impacts Developing its digital finance sector would be an opportunity for the EU to enhance its strategic autonomy in financial services. Challenging the US dollar would require the euro-area to rebalance its economy away from foreign to domestic demand. Member state division will prevent the economic reconfiguration the euro-area needed to make the euro a truly global currency.

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