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991.

The economic viability of the split-phase glycolysis process for the recycling of any kind of flexible polyurethane foam waste employing crude glycerol as cleavage agent has been demonstrated. First, experiments at pilot plant scale were carried out to check that the process can be extrapolated to larger scales. With the goal of scaling-up the process from laboratory scale to pilot plant, geometric similarity criteria were applied together with dynamic similarity for laminar flow in agitated tank reactors. Hence, a pilot plant installation was designed with geometrically similar equipment to those used for lab scale, obtaining analogous results in terms of recovered polyol properties. Then, the basic design of a split-phase glycolysis industrial plant with a capacity for treating 270 Tm per year of flexible PU foams scraps was proposed. Finally, the economic feasibility of such recycling process was confirmed because of the obtention of a Net Present Value (NPV) of 1,464,555€, with an Internal Rate of Return (IRR) of 27.99%, and a payback time between 4 and 5 years.

  相似文献   
992.
Journal of Material Cycles and Waste Management - In this study, the amount of medical waste generated in a high-populated city in Turkey between January 2018 and August 2021 was evaluated, and the...  相似文献   
993.
Journal of Material Cycles and Waste Management - Biofilters have been recognized as a key technology in the mitigation of greenhouse gases (GHG) emitted by landfills. This study aimed to evaluate...  相似文献   
994.
Journal of Material Cycles and Waste Management - Solid waste management is the main topic of the circular economy and remains a challenge for public management, because despite the recent economic...  相似文献   
995.
Journal of Polymers and the Environment - In recent decades, the global accumulation of plastics and the resulting pollution, as well as the increase in the price of oil, have driven studies aimed...  相似文献   
996.
Journal of Polymers and the Environment - Poly(3-hydroxybutyrate) (PHB) is a natural and biodegradable polyester which represents an alternative to replace conventional plastics in the packaging...  相似文献   
997.
Journal of Polymers and the Environment - Bioactive biodegradable films are emerging biomaterials in the food packaging field. This study aims to investigate the effect of different Cenostigma...  相似文献   
998.
Environmental Geochemistry and Health - Bottled natural mineral waters from an andesitic aquifer in Slovenia are enriched in magnesium (1.1 g/l), sulphate (2.2 g/l) and dissolved...  相似文献   
999.
The pink pigeon (Nesoenas mayeri) is an endemic species of Mauritius that has made a remarkable recovery after a severe population bottleneck in the 1970s to early 1990s. Prior to this bottleneck, an ex situ population was established from which captive-bred individuals were released into free-living subpopulations to increase population size and genetic variation. This conservation rescue led to rapid population recovery to 400–480 individuals, and the species was twice downlisted on the International Union for the Conservation of Nature (IUCN) Red List. We analyzed the impacts of the bottleneck and genetic rescue on neutral genetic variation during and after population recovery (1993–2008) with restriction site-associated sequencing, microsatellite analyses, and quantitative genetic analysis of studbook data of 1112 birds from zoos in Europe and the United States. We used computer simulations to study the predicted changes in genetic variation and population viability from the past into the future. Genetic variation declined rapidly, despite the population rebound, and the effective population size was approximately an order of magnitude smaller than census size. The species carried a high genetic load of circa 15 lethal equivalents for longevity. Our computer simulations predicted continued inbreeding will likely result in increased expression of deleterious mutations (i.e., a high realized load) and severe inbreeding depression. Without continued conservation actions, it is likely that the pink pigeon will go extinct in the wild within 100 years. Conservation rescue of the pink pigeon has been instrumental in the recovery of the free-living population. However, further genetic rescue with captive-bred birds from zoos is required to recover lost variation, reduce expression of harmful deleterious variation, and prevent extinction. The use of genomics and modeling data can inform IUCN assessments of the viability and extinction risk of species, and it helps in assessments of the conservation dependency of populations.  相似文献   
1000.
Environmental Chemistry Letters - Water contamination by emerging contaminants is increasing in the context of rising urbanization, industrialization, and agriculture production. Emerging...  相似文献   
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