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AbstractThe United Nations aim to perform a transition toward a sustainable environment where people can live by decoupling economic growth from resource use. Through the definition of the Agenda 2030 and the corresponding sustainable development goals, this transition asks for a lower dependence on non-renewable resources and for the use of recycled materials in a finite term perspective. In this respect, we provide an optimal control model which searches for an efficient allocation of labor between non-recycling and recycling sectors exploiting a given non-renewable resource. The optimization process is carried out over a finite time horizon in accordance with the need of rapidly achieving the targets imposed by the ecological transition. By employing the classical tools of optimal control theory, a complete theoretical analysis of the model well-posedness is developed under the assumption of linear production in both sectors. The approach is applied in order to simulate a hypothetical test case.

The re-use of construction and demolition, ceramic and similar waste in the construction industry has aroused considerable interest in recent years, as an avenue for furthering the sustainable use of resources and reducing the volume of waste dumped in landfills. Recycling materials as components in the manufacture of cement-based products, however, calls for an understanding of the leachability of the elements present in the new materials that may be harmful to human health or the respective ecosystems. The present study addresses the effect of including recycled ceramic sanitary ware waste as a partial substitute (25%) for natural coarse aggregate in the manufacture of recycled concrete in direct contact with water intended for human consumption. The findings show that the inclusion of ceramic aggregate raises the alkali concentration (Na and K) slightly and lowers the concentration of other elements (B, Si, Cl and Mg) in the water. The levels of all the leached elements were observed to be lower than the limits specified in the legislation in effect on water for human consumption. Consequently, these new concretes are apt for use in such applications, for they ensure water quality. ; Peer reviewed

Construction industry is one of the most important fractions of economy worldwide. This industry consumes enormous amounts of raw materials and produces considerable waste. The optimization of construction material usage not only saves costs but also can significantly contribute towards sustainable development. The concept of recycling the construction and demolition rubble is being addressed in this study as a solution. The recycling of concrete, resulting from both the construction activities and the demolition activities, in order to be used as a source of aggregate is being focused upon in this study. Although the idea of using recycled concrete has been implemented widely in the United States and European construction industries, one can find that the idea is still limited in most of the developing countries and Egypt is one of these nations as well. This study raises the questions of: Why the use of recycled concrete, as a source of aggregate, is still limited in Egypt and why are contractors and consultants still not encouraged to adopt the Recycled Concrete Aggregate notion even in small construction jobs? In order to address these questions, a survey has been performed within a wide range of entities that are involved in the construction and demolition waste industries in Egypt. Most of those entities have figured out that the absence of the codes of practices, field experiences, and the know-how, and the environmental and economic concerns are some of the main reasons behind these questions. The study introduces the problem and an overview on the situation in Egypt concerning the recycling of concrete. It tackles the development of the concept of concrete recycling and presents the past world experiences in the field of concrete recycling. Moreover, a survey questionnaire is being presented covering the situation in the Egyptian construction and demolition waste industries. It also provides the know-how of recycling concrete in the form of the layout of production plants, recycling process and crushing mechanisms. In addition, the material (Recycled Concrete Aggregate) performance and the environmental and economic concerns in recycling concrete are being tackled in the study. The study attempts to develop both an economic model to assess the national savings that could result from recycling concrete waste and also to evaluate the viability of creating markets for recycled concrete aggregate. Moreover, some specification limits for recycled aggregate properties are being proposed by the study. The overriding conclusions of the study reveal that the government should address codes of practices and should also address taxes, levies, and subsidies in order to encourage the application of concrete recycling. Some recommendations for future studies are also presented.

Intro -- Contents -- About the Editor -- Carbon Footprints of Recycled Plastic Packaging and Household Food Consumption by Gender in Spain -- 1 Introduction -- 2 Literature Review -- 3 Methodology -- 3.1 Data Collection -- 3.2 Data Homogeneity -- 3.3 Carbon Footprints -- 4 Main Results -- 4.1 Carbon Footprint and Emissions Pattern -- 4.2 Consumption Patterns: Food, Restaurants and Age Group -- 4.3 Emissions from Food Packaging -- 4.4 Household Packaging Waste and Recycling -- 5 Conclusions and Discussion -- References -- The Potential of Refuse-Derived Fuel Production in Reducing the Environmental Footprint of the Cement Industry -- 1 Introduction -- 2 A Brief Overview of Cement Industry Environmental Challenge -- 3 Co-benefits and Risks of Co-processing in Cement Industry -- 4 The Refuse-Derived Fuel Use in Cement Plants -- 5 The Refuse-Derived Fuel Potential: A Case Study in Brazil -- 6 Environmental Footprint Discussion -- 7 Final Remarks -- References -- Ecological Footprint of Multi-silicon Photovoltaic Module Recycling -- 1 Introduction -- 2 Photovoltaic Technology -- 2.1 Types of PV Modules -- 3 Global Market and Waste Generation -- 4 Methods of Recycling PV Modules -- 5 Ecological Footprint (EF) -- 6 Methodology -- 6.1 Ecological Footprint of Solar PV Panel Recycling (EFR) -- 7 Results -- 7.1 Ecological Footprint of Dismantling (EFdismantling) -- 7.2 Ecological Footprint of Remelting of Glass (EFremelting) -- 7.3 Ecological Footprint of Thermal Treatment (EFthermal) -- 7.4 Ecological Footprint of Chemical Treatment (EFchemical) -- 8 Conclusions -- References -- An Environmental Construction and Demolition Waste Management Model to Trigger Post-pandemic Economic Recovery Towards a Circular Economy: The Mexican and Spanish Cases -- 1 Introduction -- 2 Objective and Methodology -- 3 Materials and Methods.

examines the structural components of waste and looks at how best to transform those waste materials into advanced materials that can be utilised for high-end applications. Advanced Materials from Recycled Waste examines the structural components of waste and looks at how best to transform those waste materials into advanced materials that can be utilized for high-end applications. Sections explore what is meant by Waste - looking at what are the sources, types of waste, and the management techniques and three sections dealing with specific types of waste materials, including Industrial, Agricultural and Plastics/Polymers. Classification, characterization, utilization of, physical and mechanical properties, and design and development are explored for each of these materials. Each section concludes with a review of the challenges and future prospects for their utilization. This book will be a vital resource for a broad audience interested in the reuse of waste materials, including materials scientists and materials engineers in industry involved in the recycling, reuse and reclamation of materials and industrial byproducts, and some more general environmental scientists and engineers involved in sustainable development