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The construction, demolition, and renovation industries are among the largest contributors to global carbon emissions and waste. With decreased landfill capacities, increased waste diversion targets, resource shortages, and the recognition that material waste is critical to climate change, diverting demolition waste is now a significant priority in waste management. Deconstructing a structure and reusing its building components can significantly reduce the environmental burdens imposed. However, to optimize the reuse of building materials and components for their environmental, societal, and economical benefits, the reclamation procedure must be undertaken in a more rational and robust manner. There are currently gaps in frameworks and tools that involve the assessment of reusable building components in demolition projects. This paper develops a reclamation framework to assess the viability of recovering and reusing building components. The framework first describes a process for conducting a technical audit and uses an assessment tool to suggest a level of deconstruction based on the physical parameters of the building circumstances. The framework complements this initial outcome by then assessing additional comprehensive parameters, such as the cost, the heritage value, and the available timeframe to arrive at a suggested outcome of actions, which can range from complete demolition and basic material recovery to deliberately removing salvageable items. The framework is then applied to an older, detached office building as a conceptual case study for demonstration. The recommended level of deconstruction appears appropriate based on the visual assessment of the structure. The result of this paper promotes the circular economy and supports the United Nations Sustainable Development Goals (UN SDGs) by presenting a notably more insightful and guided approach to capturing deconstruction waste. [ABSTRACT FROM AUTHOR]

The application of fixed activated sludge with an attached growth process (FASAG) with optimal operating conditions (hydraulic retention time (HRT) of 7 h, dissolved oxygen (DO) of 6 mg/L, and alkalinity dosage of 7.14 mgCaCO3/mgN-NH4+) treats wastewater generated from office buildings to meet discharge requirements (as per the regulation in the nation where the study was conducted) with typical parameters such as pH of 6.87–7.56, chemical oxygen demand (COD) of 32–64 mg/L, suspended solids (SS) of 8–11 mg/L, N-NH4+ of 1–7 mg/L, and denitrification efficiency reaches 53%. In addition, the FASAG is an outstanding integration that makes both economic and environmental sense when applied in local wastewater treatment systems. In particular, this process combines aerobic and anoxic processes in a creation tank. This explains why this approach can save investment and operating costs, energy, and land funds. In office building regions, where land area is frequently limited, saving land funds presents numerous options to enhance the density of green cover. Furthermore, as a new aspect, investing in reusing wastewater after treatment to irrigate plants or flush toilets in office buildings contributes to a decrease in the quantity of wastewater released into the environment, saving water resources and supporting sustainable development. [ABSTRACT FROM AUTHOR]

The construction, demolition, and renovation industries are among the largest contributors to global carbon emissions and waste. With decreased landfill capacities, increased waste diversion targets, resource shortages, and the recognition that material waste is critical to climate change, diverting demolition waste is now a significant priority in waste management. Deconstructing a structure and reusing its building components can significantly reduce the environmental burdens imposed. However, to optimize the reuse of building materials and components for their environmental, societal, and economical benefits, the reclamation procedure must be undertaken in a more rational and robust manner. There are currently gaps in frameworks and tools that involve the assessment of reusable building components in demolition projects. This paper develops a reclamation framework to assess the viability of recovering and reusing building components. The framework first describes a process for conducting a technical audit and uses an assessment tool to suggest a level of deconstruction based on the physical parameters of the building circumstances. The framework complements this initial outcome by then assessing additional comprehensive parameters, such as the cost, the heritage value, and the available timeframe to arrive at a suggested outcome of actions, which can range from complete demolition and basic material recovery to deliberately removing salvageable items. The framework is then applied to an older, detached office building as a conceptual case study for demonstration. The recommended level of deconstruction appears appropriate based on the visual assessment of the structure. The result of this paper promotes the circular economy and supports the United Nations Sustainable Development Goals (UN SDGs) by presenting a notably more insightful and guided approach to capturing deconstruction waste.

The availability of freshwater is evolving as a serious threat to the living community throughout the world due to rapid industrialization, urbanization, and rising population. The depletion of groundwater due to excessive water withdrawal and reduced recharge and pollution of the water sources also contributes to this water crisis. The rising pressure on water supplies encourages the use of treated wastewater as an alternative resource. In this study, a global outlook of the developments in water reuse is presented with a focus on the Indian scenario. It can be observed that though there is a scope for water reuse in India owing to the generation of a high volume of wastewater, it is often squandered due to limited research and guidance, and unreliable institutional framework. It is suggested that the reuse of wastewater requires the development of an integrated approach considering all the factors related to technical feasibility, financial viability, and social acceptance together with a guiding management structure that may augment the existing water supplies. HIGHLIGHTS Provides an overview of factors influencing water reuse throughout the world.; Discusses regional challenges with regard to the implementation of water reuse schemes worldwide.; Provides insight to the existing reuse scenario and future opportunities in India.;

The commercial laundry industry is a vastly important yet gravely underestimated business area. In the last decades, the evolving chemical restrictions, sustainability-based regulations, and safety standards have strongly affected the commercial laundry sector, especially with environmental consideration rising in demand, that is, wastewater treatment and recycling. This paper addresses a growing need in cost-effective engineering, as well as the application, of wastewater recycling technologies for commercial laundries. This study started from the manufacturing of polypropylene capillary membranes using a combination of polyetherpolyamide (PEBAX®) and titanium dioxide nano-sized particles (nano-TiO2) for subsequent "flow coating" modification of membrane surfaces. In the next step, the material characteristics of the polymeric membranes were investigated at lab and pre-industrial scales using scanning electron microscopy/energy-dispersive X-ray spectroscopy, contact angle measurements, and defined filtration experiments. The examination of the wastewater reuse potential of novel membranes on a pre-industrial scale was carried out in a field study in a commercial laundry. The treated water has been monitored, for example, by conductometry and surface tension measurements. This study defines the reuse potential of laundry wastewater by using modified polymeric membranes, while at the same time evaluating the critical parameters of this wastewater recycling process in commercial laundries. [ABSTRACT FROM AUTHOR]

Turning from linear to circular business model, from cradle-to-grave to cradle-to-cradle and from waste to wealth, the concept of circular economy (CE) has become an important tool to promote sustainable development as it combines economic, environmental and social benefits at a local as well as global scale. In the shift towards CE, examining the CE from the perspective of its potential is crucial for its wider and more effective implementation in the practice. The aim of the paper is to clarify a circularity phenomenon in closed-loop economy under the notion of potential in part of (1) the structural elements, (2) underlying categories and (3) basal properties as a follow-up to the previous studies about managing the circularity potential. The study provides the theoretical framework for understanding circularity potential by developing the circularity potential categorization in order to get a comprehensive picture of what has been done in the past and where efforts are most need today to achieve a progress towards circularity in the future. The basal properties of circularity potential such as integrity, dynamism, territorial affiliation and different strategies compatibility were revealed and discussed for managing the circularity potential. The findings of the paper have ambition to contribute to new metrics development to measure the progress towards zero-waste and CE aimed at identification and monitoring all the possible forms of the circularity potential -- opportunities, reserves, available resources, rather than the available resources only that were primarily considered in the past attempts at the operationalisation of circular economy. [ABSTRACT FROM AUTHOR]

Abstract The reuse of mining waste-rocks as construction material constitutes an innovative management approach consistent with the principles of sustainable development. Nevertheless, the implementation of this approach is still limited by most guidelines due principally to insufficient knowledge of these materials performances and to unjustified presumptions related to their chemical instability (presence of sulfide). This paper approaches these issues by assessing the reuse potential of low-sulfide mining waste-rocks as aggregates for concrete regarding to the Quebec (Canada) recycling guidelines of non-hazardous inorganic wastes as construction materials. Toxicity characteristic leaching procedure (TCLP), comprehensive physical, chemical (XRF and ICP-AES) and mineralogical investigations (XRD and SEM) as well as modern automated mineral liberation analyses have been carried out. In addition, UCS results of various concrete mixtures using different binders were then presented to illustrate the reuse potential of the waste-rocks. The TCLP test showed the nonhazardous character of the waste rocks. They contained low sulfide content (0.5 wt%), which classify them as non-acid generating and able to meet the classification in recycling category including concrete production. Moreover, liberation analyses showed that most sulfides are concentrated in the fine fraction as pyrite occurrence with a liberated fraction of only 2%. These results influenced significantly the properties of the resulting concretes, which presented good mechanical performances especially when coarse waste rock above 20 mm and fine one below 80 μm was removed. Highlights • TCLP test showed that waste rocks is a non-hazardous material. • Grain size distribution of coarse waste rocks fraction was similar to reference gravels used for concretes production. • Total sulfur content of waste rocks was not exceeding 0.5 wt%, classifying the material as non-acid generating. • Iron sulfides (mainly of pyrite) are almost encapsuled within gangue mineral. Only 2% of pyrite is free. • Natural sand instead of the waste rocks fine fraction improve the concrete strength. [ABSTRACT FROM AUTHOR]

The reuse of some industrial by-products in the construction industry saves natural resources and energy, while at the same time reduces environmental problems related to their surface disposal. Mine tailings are currently among the largest industrial by-products in the world, and yet, only limited studies have been conducted to evaluate their reuse potential. Moreover, abandoned base-metal tailings are increasingly used in some developing countries for the manufacture of mortars without any control, engineering basis or environmental concern. In this study, an experimental program using mechanical tests, mineralogical investigations and leaching tests is presented to assess the use of low sulfide base-metal tailings, with varying properties, as fine aggregates for rendering and masonry mortars. An authentic case study illustrating their use in Moroccan construction is additionally presented. Overall, it was observed that the main properties affecting the performances of these tailings-based mortars are the residual Pb–Zn concentrations and the fine content of each tailing. The Pb–Zn fraction, when using the appropriate substitution level, may serve as an active set retardant improving mortars setting time. The leaching of metals was also successfully stabilized in mortars. [ABSTRACT FROM AUTHOR]

The use of fungal species to remove organic and inorganic pollutants from wastewater has shown to be a good alternative to traditional wastewater treatment technologies. Fungal pellets are well settling aggregates formed by self-immobilization. Their use in bioreactors is promising as it avoids the practical and technical difficulties usually encountered with dispersed mycelium. This review presents the mechanisms involved in the formation and growth of fungal pellets as well as the different factors that influence the stability of the pellets. The various types of fungal pelleted bioreactors that are used for wastewater treatment, their configuration, design and performance are reviewed. A summary of the different organic and inorganic pollutants that have been treated using fungal pelleted reactors, from dyes to emergent pollutants such as pharmaceuticals, is discussed from an application view-point. The operational issues such as bacterial contamination and longevity of this bioprocess under non-sterile conditions, as well as the reuse of fungal pellets are also encompassed in this review. [ABSTRACT FROM AUTHOR]

Reuse of treated wastewater has been proven a reliable alternative water resource, which can constitute a significant component of integrated water resources management and provide an effective solution to cope with water scarcity conditions. In Greece, the recent introduction of the Joint Ministerial Decision 145116/11, which specifies requirements concerning the reuse of treated effluents, gives rise to the investigation of reuse potential in water scarce regions. As most Aegean islands struggle with water scarcity, due to their specific geomorphology, climatic conditions, and increased water demand during summer, the implementation of wastewater reuse in this region could provide a key solution to address water stress. The aim of this paper is to propose a step-wise approach for the analysis of treated wastewater reuse potential in the islands of the Aegean Archipelago, and the assessment of its contribution towards the mitigation of water scarcity problems. A Geographic Information System was used for the classification of the islands according to certain criteria (e.g. operative WWTPs, vulnerability to water scarcity, population density, etc.) and their clustering according to wastewater reuse potential. For the cluster of high reuse potential, the quality of treated effluents was compared to the standards specified by the Greek wastewater reuse legislation, to identify potential reclaimed water uses. The contribution of reclaimed water in alleviating water deficits in the islands with high reuse potential was estimated to be significant, thus indicating that it could be an effective option towards water scarcity mitigation. [ABSTRACT FROM AUTHOR]

Abstract: This study advances contemporary ideas promoting the importance of managing wastes as resources such as closed-loop or circular material economies, and sustainable materials management by reinforcing the notion of a resource-based paradigm rather than a waste-based one. It features the creation of a quantitative tool, the “reuse potential indicator” to specify how “resource-like” versus how “waste-like” specific materials are on a continuum. Even with increasing attention to waste reuse and resource conservation, constant changes in product composition and complexity have left material managers without adequate guidance to make decisions about what is technically feasible to recover from the discard stream even before markets can be considered. The reuse potential indicator is developed to aid management decision-making about waste based not on perception but more objectively on the technical ability of the materials to be reused in commerce. This new indicator is based on the extent of technological innovation and commercial application of actual reuse approaches identified and cataloged. Coal combustion by-products (CCBs) provide the test case for calculating the reuse potential indicator. While CCBs are often perceived as wastes and then isolated in landfills or surface impoundments, there is also a century-long history in the industry of developing technologies to reuse CCBs. The recent statistics show that most CCBs generated in Europe and Japan are reused (90–95%), but only 40–45% of CCBs are used in the United States. According to the reuse potential calculation, however, CCBs in the United States have high technical reusability. Of the four CCBs examined under three different regulatory schemes, reuse potential for boiler slag and flue-gas desulfurization gypsum maintains a value greater than 0.8 on a 0–1 scale, indicating they are at least 80% resource-like. Under current regulation in the United States, both fly ash and bottom ash are 80–90% resource-like. Very strict regulation would remove many reuse options decreasing potential for these two CCBs to 30% resource-like. A more holistic view of waste and broad application of the new indicator would make clear what technologies are available and assist public and private decision makers in setting quantitative material reuse targets from a new knowledge base that reinforces a resource-based paradigm. [Copyright &y& Elsevier]

The article presents a study which evaluates the effluent reuse potential of municipal wastewater treatment plants (MWWTPs) in Taiwan using grey relation analysis based on quantity and quality. The study calculates the grey relation grade (GRG) of the MWWTPs using the three effluent quality indices and flowrate. Results revealed that the better MWWTP effluent quality was associated with higher reuse potential without being affected significantly by the quantity.