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Simone ManfrediDavide Tonini Thomas H. Christensen 《Resources, Conservation and Recycling》2011,55(11):995-1004
Several alternatives exist for handling of individual waste fractions, including recycling, incineration and landfilling. From an environmental point of view, the latter is commonly considered as the least desirable option. Many studies based on life-cycle assessment (LCA) highlight the environmental benefits offered by incineration and especially by recycling. However, the landfilling option is often approached unjustly in these studies, maybe disregarding the remarkable technological improvements that landfills have undergone in the last decades in many parts of the world.This study, by means of LCA-modelling, aims at comparing the environmental performance of three major management options (landfilling, recycling and incineration or composting) for a number of individual waste fractions. The landfilling option is here approached comprehensively, accounting for all technical and environmental factors involved, including energy generation from landfill gas and storage of biogenic carbon. Leachate and gas emissions associated to each individual waste fraction have been estimated by means of a mathematical modelling. This approach towards landfilling emissions allows for a more precise quantification of the landfill impacts when comparing management options for selected waste fractions.Results from the life-cycle impact assessment (LCIA) show that the environmental performance estimated for landfilling with energy recovery of the fractions “organics” and “recyclable paper” is comparable with composting (for “organics”) and incineration (for “recyclable paper”). This however requires high degree of control over gas and leachate emissions, high gas collection efficiency and extensive gas utilization at the landfill. For the other waste fractions, recycling and incineration are favourable, although specific emissions of a variety of toxic compounds (VOCs, PAHs, NOx, heavy metals, etc.) may significantly worsen their environmental performance. 相似文献
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In this study, two pilot-scale aerobic landfill reactors with (A1) and without (A2) leachate recirculation are used to obtain
detailed information on the quantity and quality of leachate in aerobic landfills. The observed parameters of leachate quality
are pH, chloride (Cl−), chemical oxygen demand (COD), biological oxygen demand (BOD), total Kjeldahl nitrogen (TKN), ammonia nitrogen (NH3-N), and nitrate (NO3–-N). pH values of the leachate increased to 7 after 50 days in reactor A1 and after 70 days in reactor A2. Cl− concentrations increased rapidly to 6100 (A1) and 6900 (A2) mg/L after 80 days, from initial values of 3000 and 2800 mg/L,
respectively. COD and BOD values decreased rapidly in the A1 landfill reactor, indicating the rapid oxidation of organic matter.
The BOD/COD ratio indicates that leachate recirculation slightly increases the degradation of solid waste in aerobic landfills.
NH3-N concentrations decreased as a result of the nitrification process. Denitrification occurred in parts of the reactors as
a result of intermittent aeration; this process causes a decrease in NO3− concentrations. There is a marked difference between the A1 and A2 reactors in terms of leachate quantity. Recirculated leachate
made up 53.3% of the leachate generated from the A1 reactor during the experiment, while leachate quantity decreased by 47.3%
with recirculation when compared with the aerobic dry landfill reactor. 相似文献
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Viatcheslav Moutavtchi Jan Stenis William Hogland Antonina Shepeleva Håkan Andersson 《Journal of Material Cycles and Waste Management》2008,10(1):62-70
A cost methodology is proposed for evaluating the ecological-economic efficiency of a municipal solid waste management scheme
based on the recommendations of cost-benefit analysis and the full-cost accounting methodology for municipal solid waste management.
The methodology employs the previously introduced waste managements’ efficient decision (WAMED) model and the company statistical
business tool for environmental recovery (COSTBUSTER) indicator. A case study presents the practical application of the proposed
cost-benefit analysis-based theory to the landfilling concept currently applied in Kalmar, Sweden. It is concluded that the
presented provisions for evaluation of the ecological-economic efficiency of a municipal solid waste management scheme reflect
a novel integrated approach to solving the problem of simultaneously decreasing the negative impacts of municipal solid waste
on the environment and the health of the population while providing an information support tool for decision making in municipal
solid waste management at regional and municipal levels to improve small-and medium-sized company competitiveness in particular. 相似文献
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S. Sözen E. Ubay Cokgor G. Insel D. Okutman Tas H. Dulkadiroglu C. Karaca A. Filibeli S. Meric D. Orhon 《Waste management (New York, N.Y.)》2014,34(9):1657-1666
This study evaluated the scientific and technical basis of the dissolved organic carbon (DOC) limitation imposed on municipal sludge for landfilling, mainly for assessing the attainability of the implemented numerical level. For this purpose, related conceptual framework was analyzed, covering related sewage characteristics, soluble microbial products generation, and substrate solubilization and leakage due to hydrolysis. Soluble COD footprint was experimentally established for a selected treatment plant, including all the key steps in the sequence of wastewater treatment and sludge handling. Observed results were compared with reported DOCs in other treatment configurations. None of the leakage tests performed or considered in the study could even come close to the prescribed limitation. All observed results reflected 10–20 fold higher DOC levels than the numerical limit of 800 mg/kg (80 mg/L), providing conclusive evidence that the DOC limitation imposed on municipal treatment sludge for landfilling is not attainable, and therefore not justifiable on the basis of currently available technology. 相似文献
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The presence in waste of emerging pollutants (EPs), whose behaviours and effects are not well understood, may present unexpected health and environmental risks and risks for the treatment processes themselves. EP may include substances that are newly detected in the environment, substances already identified as risky and whose use in items is prohibited (but which may be present in old or imported product waste) or substances already known but whose recent use in products can cause problems during their future treatment as waste. Several scientific studies have been conducted to assess the presence of EP in waste, but they are mostly dedicated to a single category of substance or one particular waste treatment. In the absence of a comprehensive review focused on the impact of the presence of EP on waste treatment schemes, the authors present a review of the key issues associated with the treatment of waste containing emerging pollutants. This review presents the typologies of emerging pollutants that are potentially present in waste along with the major challenges for each treatment scheme (recycling, composting, digestion, incineration, landfilling and wastewater treatment). All conventional treatment processes are affected by these new pollutants, and they were almost never originally designed to consider these substances. In addition to these general aspects, a comprehensive review of available data, projects and future R&D needs related to the impact of nanoparticles on waste treatment is presented as a case study. 相似文献
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Lead and polybrominated flame retardants are the two hazardous materials that can be found in electronic appliances. Particularly, cathode ray tubes (CRT) contain leaded glasses. In a computer monitor, over 98% of the lead is in the CRT. This material is generally not accepted for reuse as a component; only those from televisions can be reused. However, this currently represents only a very small market. Envirocycle (a US company) has developed a process to recycle all glasses contained in CRTs; this process includes cleaning and sorting glass. The product obtained is used for the manufacture of new CRT glass. Some industries have used pulverized glass from CRTs in smelting processes as slagging material instead of sand or slag. In this paper, some environmental issues related to the recycling of computers and television sets, and CRTs from computers are presented and discussed. Different processes used to recycle CRTs are described along with an economic analysis. 相似文献
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Munawar Ali Junli Zhang Roberto Raga Maria Cristina Lavagnolo Alberto Pivato Xu Wang Yuanyuan Zhang Raffaello Cossu Dongbei Yue 《Frontiers of Environmental Science & Engineering》2018,12(3):5
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