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Hamann Huffman posted an update 6 months, 1 week ago
A large number of industrial solid waste resources urgently need to be recycled, so, fast-expanding the utilization area of these waste resources is a pressing task in today’s China. The production of various slag wool fibers is an effective way due to the huge demand of thermal insulation materials. Besides, the preparation of slag continuous fibers is also a good choice because of its wide application fields. Two fly ash-based continuous fibers were successfully prepared by fly ash and magnesium slag, or add less feldspar, through melting at high temperature, following spinning into continuous fibers. Their samples were treated at different temperatures from 100 to 700 °C, and then investigate tensile strength and thermal resistance. As the same fly ash-based fibers, the tensile strength of two fibers in this study increase 115% and 28.3% than the fibers previously reported. Their utilization rates of solid waste resources are up to 100% and 80%, and far higher than 45% of the same fiber reported. Stenoparib in vivo FT-IR, SEM, Solid-state NMR analysis indicates that thermal action makes the 29Si structure without Al(Q3,Q2, and Q1) transfer to 29Si structure containing Al(Q4(3Al),Q4(2Al), Q4(1Al)), meanwhile, AlVI (AlO6 octahedron) was destroyed completely and converted into AlV (AlO5) and AlIV (Al3). Only some Al atoms participated in the formation of network structure in fiber, they contributed to the strength of fibers.This work deals with the revalorization of an important winery residue such as the vine shoots by the obtaining of oligosaccharides with potential prebiotic activity. The manufacture of these added-value products was performed by an autohydrolysis treatment assisted with microwaves to make the process less time consuming and more environmentally friendly. The influence of the reaction time (0-40 min) and the temperature (140-200) on the production of oligosaccharides during the microwave-assisted autohydrolysis was evaluated. The highest concentration of oligosaccharides (168.3 g/Kg oven-dried vines shoots) was achieved during the treatment carried out at 180 °C for 20 min. To assess the benefits of the assistance of the autohydrolysis treatment with the microwaves a conventionally heated treatment was performed using conditions (180 °C for 15 min) that provoked similar effects on the solubilisation of the hemicellulosic fraction. This treatment permitted the obtaining of 203.5 g oligosaccharides/Kg oven-dried vines shoots using 61.0% more of the time needed to carry out the microwaves-assisted autohydrolysis. Although the microwave-assisted treatment permitted the manufacture of a lower amount of oligosaccharides, only consumed 28.8% of the energy needed to perform the conventionally heated treatment. The oligosaccharides manufactured by the two treatments were substituted xyloglucans with different polymerization and acetylation degrees, which due to their potential prebiotic activity could be highly appreciated by pharmaceuticals and food industries. Thus, this work demonstrated the environmental sustainability of the microwave-assisted autohydrolysis for the revalorisation of the vine shoots.The generation of wasted LEDs is expected to grow in the coming years, raising the challenge of recycling and recovering their valuable and critical materials. Due to the low concentration of these materials, the current recycling processes available for LEDs have a significant recovery limitation. This study proposes an innovative, clean and effective physical method to segregate the valuable and critical materials into different fractions while enhancing their concentration particle size separation followed by electrostatic separation. After the determination of the best electrostatic separation conditions (varying tension and rotation) for each particle size, the final fractions were characterized by acid digestion and ICP-OES analysis. The analysis revealed that the economically valuable elements gold, silver, copper and tin became concentrated in the conductive fractions (80.18%, 94.22%, 96.55% and 93.29% of their total recovered mass, respectively), while the strategic critical elements, gallium, cerium and yttrium became concentrated in the non-conductive fractions (96.15%, 100% and 95.20% of their total recovered mass, respectively). Despite some limitations imposed by the mass losses, this novel route may be important to uncover new recycling alternatives, mainly for critical elements, and to improve the economic viability of the recycling routes.Management of wastes resulting from construction, renovation and demolition (CRD) activities has become an important challenge for scientists. The recovery of gypsum residues from CRD waste is one of the solutions to minimize the impact of CRD operations on the environment. This review discusses the characteristics of CRD waste, different treatment and valorization methods for both CRD waste and extracted gypsum residues. Pre-treatment based on particle size separation is the most fundamental step in the process of extracting gypsum residues from CRD fine tailings. The subsequent application of a physical, chemical or biological decontamination approach on the gypsum residues could significantly improve its quality as compared to natural gypsum. The quality of the gypsum obtained affects its valorization potential in different sectors such as cement manufacturing, the sequestration of carbon dioxide and nutrients. The valorization strategy could help reducing emissions of greenhouse gases while producing by-products that can be reused in agriculture. As such, this review may provide guidance for more sustainable management of CRD and gypsum residues in the future.Municipal solid waste incinerator (MSWI) fly ash is a residue of municipal solid waste incineration whose recycling is currently a worldwide problem. Therefore, considerable efforts are being made to establish effective recovery techniques so MSWI can be used as a substitute for natural resources in construction, as in masonry blocks, roads and so on, or in the manufacture of new materials. MSWI fly ashes contain elements such as Ca, Si and Al, which make it possible for them to be used as raw material to manufacture cements. This paper presents the results obtained from the physicochemical characterization of two MSWI fly ashes from two Spanish cities. The research aims to explore the feasibility of using MSWI fly ash as raw material for sintering belite cements. The results show that MSWI fly ashes have a suitable composition. However, appropriate pre-treatment will be required to eliminate chloride and possible traces of heavy metals and to improve pozzolanic activity. Furthermore, the addition of vitreous silica in the proper proportions is required.