scholarly journals Construction and Demolition Waste Recycling through Conventional Jig, Air Jig, and Sensor-Based Sorting: A Comparison

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 904
Author(s):  
Carlos Hoffmann Sampaio ◽  
Weslei Monteiro Ambrós ◽  
Bogdan Grigore Cazacliu ◽  
Josep Oliva Moncunill ◽  
Moacir Medeiros Veras ◽  
...  

The paper presents a comparison of the concentration methods conventional jig, air jig, and sensor-based sorting to treat construction and demolition waste. All tests were made with concrete, brick, and gypsum particles and the tests aim to separate these materials into different size ranges, depending on the method. The equipment tested, conventional jig, air jig, and sensor-based sorting present good results to concentrate construction and demolition waste particles, with different concentrations and mass recoveries. The results show particularly good mass recoveries and particle concentration for conventional jig, especially for concrete and gypsum particles. Sensor-based sorting should preferably use concentration circuits for best results.

2020 ◽  
Vol 6 (9) ◽  
pp. 73169-73180
Author(s):  
Kelly Patrícia Torres Vieira Brasileiro ◽  
Bacus de Oliveira Nahime ◽  
Michell Macedo Alves ◽  
Pâmela Millena Kunan ◽  
Vitor Alvares ◽  
...  

2021 ◽  
Vol 131 ◽  
pp. 294-304
Author(s):  
Ngoc Han Hoang ◽  
Tomonori Ishigaki ◽  
Rieko Kubota ◽  
Ton Kien Tong ◽  
Trung Thang Nguyen ◽  
...  

2021 ◽  
pp. 0734242X2110291
Author(s):  
Navarro Ferronato ◽  
Gabriela Edith Guisbert Lizarazu ◽  
Marcelo Antonio Gorritty Portillo ◽  
Luca Moresco ◽  
Fabio Conti ◽  
...  

Construction and demolition waste (CDW) management in developing countries is a global concern. The analysis of scenarios and the implementation of life cycle assessment (LCA) support decision-makers in introducing integrated CDW management systems. This paper introduces the application of an LCA in La Paz (Bolivia), where CDW is mainly dumped in open areas. The aim of the research is to evaluate the benefits of inert CDW recycling in function of the selective collection rate, defined as the amount of waste (%wt.) sorted at the source in relation to the total waste amount produced, and the distances from the CDW generation to the material recycling facility. The outcomes of the research suggest that increasing the selective collection rates (5% to 99%) spread the importance of transportation distances planning since it affects the magnitude of the environmental impacts (1.05 tCO2-eq to 20.7 tCO2-eq per km traveled). Transportation limits have been found to be lower than about 40 km in order to make recycling beneficial for all environmental impacts and for all selective collection rate, with the eutrophication potential as the limiting indicator. The theoretical analysis suggests implementing LCA with primary data and involving statistics related to the transportation of virgin materials avoided thanks to recycling. The outcomes of the research support the implementation of CDW recycling in developing countries since it has been found that material recovery is always beneficial.


Buildings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 207 ◽  
Author(s):  
Dongming Guo ◽  
Lizhen Huang

Construction and demolition waste (C&D waste) are widely recognized as the main form municipal solid waste, and its recycling and reuse are an important issue in sustainable city development. Material flow analysis (MFA) can quantify materials flows and stocks, and is a useful tool for the analysis of construction and demolition waste management. In recent years, material flow analysis has been continually researched in construction and demolition waste processing considering both single waste material and mixed wastes, and at regional, national, and global scales. Moreover, material flow analysis has had some new research extensions and new combined methods that provide dynamic, robust, and multifaceted assessments of construction and demolition waste. In this paper, we summarize and discuss the state of the art of material flow analysis research in the context of construction and demolition waste recycling and disposal. Furthermore, we also identify the current research gaps and future research directions that are expected to promote the development of MFA for construction and demolition waste processing in the field of sustainable city development.


2012 ◽  
Vol 509 ◽  
pp. 1-5
Author(s):  
Su Ping Cui ◽  
Qi Dong Liu ◽  
Jian Hua Yan ◽  
Xin Du

In this paper, the construction and demolition waste (C&D waste) recycling techniques in China is summarized, and proposed the C&D waste recycling suggestions in this foundation. The C&D waste can be divided into construction waste, decorating waste, demolition waste and natural disaster ruin waste. In addition to be buried, domestic C&D waste can be made into landscape material, roadbed material, recycled aggregate, recycled brick, recycled concrete, recycled admixture and so on. The state should establish positive promoting policies, improve the recycling industrial chain, and promote the healthy development of the C&D waste recycling.


2012 ◽  
Vol 730-732 ◽  
pp. 630-635
Author(s):  
D. Algarvio ◽  
Maria Margarida Rolim Augusto Lima ◽  
M.L. Cunha

The construction and demolition wastes (C&DW) frequently are abandoned in private properties, roads, and landfills or collected by non-licensed companies. In Portugal they are few recycling plants operating with this residue, and this work makes the bridge between the mechanical recycling process developed on semi-industrial scale, and the recycling products characterization process developed on laboratorial scale. The main goal of the present work is the quality improvement of the recycled aggregates produced by a construction and demolition waste recycling pilot plant with 50 ton/h located in Montemor-o-Novo. Process operations are the hammer mill comminution, magnetic separation and sieving (bar sieves: 0-4mm, 4-8mm and 8-12mm; and square sieves: 12-22mm, 22-31mm and above 31mm). In order to improve the magnetic separation process, several tests with different distances between the magnet and the conveyor belt were made (21-31cm). On the other hand, to improve the quality of the produced aggregates, the bar screen size fractions were analyzed, according to the Portuguese Standard (NP EN 933-1 2000). The most efficient distances for the magnetic separation process were identified as between 21 and 27cm, with efficiency between 85% and 90% respectively. According to the histograms, the more frequent red aggregate from 0-4mm size fraction are +0.425-0.850; +0.850-1.7 and +1.7-3.35. From the 4-8mm red aggregates, the more frequent size fractions are +4.75-6.7 and +6.7-9.95. Finally, from the 8-12mm red aggregates, the more frequent new size fractions are +6.7-9.50 and +9.50-13.20. Sieving results obtained from cumulative curves for red aggregate showed an decrease in the mass % amount for the size fractions: 0-4mm: 97%, 4-8mm:76% and 8-12mm: 56%. The results from cumulative curves for grey aggregate showed a light decreased in the amount mass % for the size fractions: 0-4mm: 90%, 4-8mm:56% and 8-12mm: 60%.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Jingsong Yang ◽  
Jing Zhang ◽  
Chunxiang Guo ◽  
Ruwen Tan ◽  
Minjiu Yu

In order to investigate the formulation of appropriate environmental regulations in construction and demolition waste (CDW) recycling, this paper establishes a CDW recycling decision-making system consisting of a contractor, a developer, and the government and analyses the decision-making results and influencing factors of the various stakeholders. Three different types of environmental regulations have been considered in the model: (i) no regulation, (ii) incentive regulation, and (iii) punitive regulation. The research shows that the incentive regulation offers the constructor greater incentives to recycle CDW and yields higher profits for members of the system, and however, when recycling is very costly and CDW is highly damaging, punitive regulation should be implemented, as the incentive regulation leads to lower social welfare. In addition, governments should be more cautious when adopting incentive regulation, because social welfare may be negative under this condition whereas there is no such possibility under the punitive regulation.


Sign in / Sign up

Export Citation Format

Share Document