Bui, Tat-DatTseng, Jiun-WeiTseng, Ming-LangLim, Ming K....
19页
查看更多>>摘要：This study enriches sustainable solid waste management knowledge by establishing a valid hierarchical model and critiques the causal interrelationship between waste reuse and recycling attributes. The challenges and opportunities for sustainable waste reuse and recycling are emphasized, and direction is provided for practices. Many developing and emerging countries have been attempting to address solid waste management problems and serious restrictions on material reuse and recycling activities. However, it is not well developed, and reuse and recycling efforts have not yet been well implemented due to weak economic and political institution levels. This study aims to propose a sustainable solid waste management model and address opportunities and challenges for waste reuse and recycling in a developing country. A hybrid approach is adopted using a systematic data-driven analysis comprising content analyses, system uncertainty and complexity, the fuzzy Delphi method, interpretive structural modeling, and the fuzzy decision-making trial and evaluation laboratory. The results show that 19 valid indicators are congregated into five aspects, in which circular resource management, societal requirements, and municipal sustainability are causative aspects with the capability to improve sustainable solid waste management as it regards waste reuse and recycling. The top prominent indicators helping to enhance practices are the circular economy, the informal sector, material flow analysis, policy restrictions, waste treatment technologies. The state-of-the-art literature is presented, and further opportunities and challenges are determined.
查看更多>>摘要：Anthropogenic heat (AH) emission from buildings is a key contributor to the urban heat island (UHI) effect. Although an improved understanding of spatiotemporal patterns of building AH is highly needed for mitigating UHI effect, such information is still limited in high spatiotemporal resolutions at the city level. In this study, a bottom-up city building heat emission model (CityBHEM) was developed to investigate temporal variations of building AH from three components (i.e., envelope convection, zone infiltration and exfiltration, and HVAC system) for all buildings in Boston, United States. First, buildings in Boston were grouped into eleven commercial and five residential building prototypes based on building type, construction year, and foundation type. Second, an end-use-based calibration was developed to calibrate CityBHEM using U.S. Energy Information Administration's survey data. Finally, AH from all buildings in the city under actual weather conditions was calculated using the calibrated CityBHEM model together with building types and sizes. Results indicate that total building AH density of Back Bay neighborhood reaches the maximum value of 526 kWh/m(2) in summer (56% of HVAC system and 44% of envelope convection) and the minimum value of 369 kWh/m(2) in winter (54% of HVAC system, 24% of envelope convection and 22% of zone infiltration and exfiltration). In contrast, total building AH density of suburban neighborhoods is lower than 30 kWh/m(2) in summer and 20 kWh/m(2) in winter. Given that key inputs are publicly available, CityBHEM is transferable to other U.S. cities, enabling us to explore practical building energy-saving strategies for mitigating AH.
Akan, Otobong DonaldOkeke, Emmanuel SundayOkoye, Charles ObinwanneAtakpa, Edidiong Okokon...
16页
查看更多>>摘要：This work reviews microplastic's impact on agroecosystem components and possible effects on the food chain. Microplastics are sized < 5 mu m, made up of diverse chemical constituents, and come from several sources. The agroecosystems reportedly receive an estimated 1.15 to 2.41 million tonnes of plastic wastes annually. Microplastic factors like increasing anthropogenic activities, tiny sizes, ubiquity, sheer volume, and composite chemicals greatly influence the environment. Their impact could be directly on the food substances or indirectly on the ecosystems that support the primary producers of the food chain: alters plant's growth and developments, blocks organisms' digestive/roots system, attachment for multiplying organisms, vectors of toxic compounds, disrupts the activities of microbial decomposers and nutrient cycles, etc. Microplastic contamination of the agroecosystems reduce food yields, impact the food chain components negatively, food security, and human health. The adoption of regenerative agriculture is staging the cultivation of food substances away from contaminable systems while using sustainable sources of water and minerals. The consequences of increasing microplastic volume and attendant impacts make researchers evaluate alternative solutions for microplastic abatement: bio-based plastics and the adoption of clean remedial biotechnologies. These alternate solutions are expedient as the total elimination of plastic (microplastic) waste may not be fully feasible- considering their recalcitrance and non-biodegradability. Also, policymakers should promulgate laws that mitigate and replace single-use and non-biodegradable plastic materials with bio-based or biodegradable alternatives.
Villagran-Zaccardi, Yury A.Marsh, Alastair T. M.Bernal, Susan A.Sosa, Maria E....
16页
查看更多>>摘要：Global demand for buildings and infrastructure is extremely high as provision of shelter, sanitation and healthcare are paramount to safeguard the world's growing population. Concrete is a preferred construction material to meet this demand, but its production is leading to overexploitation of natural gravel and sand, causing an environmental crisis in regions where these materials are extracted unsustainably. Waste concrete is available globally, particularly in regions with fast growth of the built environment, and those struck by coordinated attacks, earthquakes or severe weather events. Waste concrete has mainly been used for producing recycled aggregates; however, its full recycling is still not practiced. Alternative uses include applications as fine recycled aggregates, supplementary cementitious materials, filler, and feedstocks for clinker production. These technologies still face challenges concerning their adoption and eco-efficiency. Restricted knowledge and operational barriers have also prevented implementation of beneficiation technologies for complete re-recycling of waste concretes, particularly the fine fractions produced during crushing. Despite these issues, it is recognised that the complete utilization of waste concrete offers unique opportunities for supply chain security, reducing natural resources consumption and enabling to move towards a Circular Economy. Harmonizing current practices for the treatment of waste concrete and the by-products generated during their processing, is a first step toward policy and standards development to enable their widespread use. This critical discussion addresses challenges and opportunities, as well as facilitation strategies needed to progress the complete re-utilization of waste concrete as a valuable resource for creating sustainable future infrastructure.
查看更多>>摘要：In this study, self-sustained ultrafiltration (SUF) without extra backwashing, aeration and chemical cleanings was investigated. To further improve removal performance and membrane permeability, vermifiltration (VF) was introduced, developing VF/SUF (VF coupling SUF without reflux) and RVF/SUF (VF coupling SUF with reflux). Synergism effects of contaminants removals were achieved with effective removals of dissolved pollutants (e.g., 95.97% of TOC and 45.25% of NH3-N) via VF process, simultaneously with efficient rejections of particles, bacteria, protozoa and metazoan via SUF process, ensuring permeate safety. Notably, vermifilters improved the membrane flux by over 101% relative to the control, attributing to the synergetic effects among the modified biofouling layer structure by more prosperous eukaryotic communities, the reduction of extracellular polymeric substances and the increase of inorganics contents. With the usage of reflux, the membrane flux was further elevated by 181% since the reflux delivered more eukaryotes into SUF to increase the heterogeneity of the biofouling layer.
Battegazzore, DanieleCravero, FulviaFrache, Alberto
9页
查看更多>>摘要：A survey on Covid-19 protecting masks habits carried out on the Italian population at the end of 2020 revealed that disposable face masks are the most used, thus resulting in a considerable quantity of waste. Therefore, a separate collection of these devices based on local platforms such as schools, offices and factories is proposed. This would limit collecting costs, ensure the origin and quantity and simplify the sanitizing treatment of the masks, in order to allow their introduction into the industrial recycling stream of plastic materials. In this scenario, an urban separate waste collection material (namely mixed polyolefin) was selected and melt blended in several ratios with the disposable filtering masks. Two recycling solutions have been envisaged: the use of the filtering part alone or the joint introduction of the ear loops. Compared to the mixed polyolefin, the resulting recycled materials from filtering face masks have lower viscosity but comparable toughness and superior stiffness and strength. The presence of ear loops in the recycled improves the rigidity but slightly decrease the viscosity and worsen both the strength and toughness. Furthermore, conceiving an outdoor application, the stability to photo oxidation was investigated through an accelerated aging process. The elaborated degradation rate of the masks material is similar to a commercial polypropylene, while for the mixed polyolefin is greatly reduced. The mixed compounds have intermediate degradation rates.
查看更多>>摘要：Water sustainability is at the core of high-tech industries and reflects their efforts in terms of both economic and environmental benefits. In this study, a membrane capacitive deionization (MCDI)-based water treatment system was proposed for the production of ultrapure water and wastewater reclamation by deionization. The system achieved good deionization performance in single-pass mode for treating soft tap water (T1), hard tap water (T2), cooling tower blowdown (W1) and wastewater discharge from high-tech industries. Overall, the removal efficiencies for hardness and conductivity in the tested scenarios were at least 70.8% and 51.9%, respectively, and selectivity in ion removal was the highest in Na+ for T1, W1 and W2 and in Ca2+ for T2, as it was mainly affected by the initial molar concentration of major ions. The system also showed favorable characteristics of high charge efficiency and relatively low energy consumption. At an applied voltage of 1.6 V, the energy requirements vary from 0.014 to 0.68 kWh/m(3) with a charge efficiency higher than 70%, while the optimal deionization time was estimated to be between 12 and 60 min considering the increase in both the mean deionization rate and mean deionization capacity for various feedwater scenarios. The levelized cost of water for the studied MCDI scenarios ranges from 0.35 to 0.53 $USD/m(3), in which the capital and material costs generally outweigh the energy and other operational costs. The results of this study are expected to provide essential techno-economic recommendations for the practical adoption of the on-site MCDI process in industries.
查看更多>>摘要：Urban areas often face versatile stressors (e.g., food security, congestion, energy shortage, water pollution, water scarcity, waste management, and storm and flooding), requiring better resilient and sustainable infrastructure systems. A system dynamics model (SDM), explored for the urban region of Orlando, Florida, acts as a multiagent model for portraying material and energy flows across the food, energy, water, and waste (FEWW) sectors to account for urban sustainability transitions. The interlinkages between the FEWW sectors in the SDM are formulated with multiple layers of dependencies and interconnections of the available resources and their external climatic, environmental, and socioeconomic drivers through four case studies (scenarios). The vital components in the integrated FEWW infrastructure system include urban agriculture associated with the East End Market Urban Farm; energy from the fuel-diverse Curtis H. Stanton Energy Center; reclaimed wastewater treated by the Eastern Water Reclamation Facility, the Water Conserv II Water Reclamation Facility, and stormwater reuse; and solid waste management and biogas generation from the Orange County Landfill. The four scenarios evaluated climate change impacts, policy instruments, and land use teleconnection for waste management in the FEWW nexus, demonstrating regional synergies among these components. The use of multicriteria decision-making coupled with cost-benefit-risk tradeoff analysis supported the selection of case 4 as the most appropriate option as it provided greater renewable energy production and stormwater reuse. The SDM graphic user interface aids in the visualization of the dynamics of the FEWW nexus framework, demonstrating the specific role of renewable energy harvesting for sustainably transitioning Orlando into a circular economy.
查看更多>>摘要：Municipal solid waste incineration (MSWI) ashes are byproducts of the combustion process at a waste-to-energy facility, often destined for the landfill. These ashes can be compositionally comparable to ordinary Portland cement, blast furnace slag, and coal fly ash. However, these ashes are largely unutilized as a supplementary cementitious material as their effect on cementitious systems is not well understood. This lack of understanding is primarily due to the elemental and mineralogical complexity of these ashes. To solve this problem, here we have analyzed the hydration behavior of ordinary Portland cement blended with 8 distinct and diverse MSWI ashes. Our results indicate that incorporating these MSWI ashes can either accelerate or retard cement hydration depending upon their composition. Specifically, Cu, Fe, Al, Ti, Si, K, Zn, and Sr from the MSWI ash matrix appear to retard cement hydration, while Pb, Br, S, Ca, and Cl appear to accelerate cement hydration. Based on these results, we introduce a new parameter - Incineration Ash Coefficient (IAC) - which correlates with the 7-day compressive strength of mortars incorporating MSWI ashes reasonably well (R-2 = 0.79). This new parameter, based on fundamental chemical and physical characteristics of ashes, is the first step towards effective screening and employment of MSWI ashes as cementitious materials.
查看更多>>摘要：This research aims to understand why consumers miss-sort plastic food packaging and to what extent the design affordance of packaging can influence consumer sorting behavior. A photo-based observation study and semi-structured interviews were used to gain a deeper understanding of the miss-sorting behavior and how it could be affected by design affordance. This explorative study suggested that the packaging form, size, durability, haptic aspects, and visual communicative properties influence how consumers perceive the value of packaging. This is important, because packaging with low attributed values are not considered worth recycling or correctly sorted and are more likely to be miss-sorted. Hence, a well-afforded food packaging design is expected to improve how consumers perceive the value of packaging and to consequently improve sorting behavior.
NSTL
Elsevier