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1.
Journal of Material Cycles and Waste Management - The use of agro-residue in resource-limited regions can be a smart way for civil construction to reduce costs, reduce emissions of pollutant gases...  相似文献   

2.
The abundance and photosynthetic activity ofpicocyanobacteria in the oligotrophic alpine lake Traunseewere measured at a station located close to the outlet ofindustrial soda waste and at a mid-lake reference stationduring spring, 1999 through to autumn, 2000.Picocyanobacterial numbers measured by flow cytometry inTraunsee (0.7–13.2 × 104 ml-1) were comparable tothose of other oligotrophic lakes, and there was nosignificant difference between the contaminated and thereference sampling location. Picoplankton (<2 m)photosynthetic rates measured in vitro by the 14C-technique were significantly reduced at the contaminated siterelative to the reference station at low photosyntheticallyavailable radiation (10 E m-2 s-1), while nodifference between these two stations was found at moderatelyhigh light intensity (100 E m-2 s-1). Theinvestigation was complemented by laboratory experiments withcultured picocyanobacteria. Three Synechococcus spp.strains were exposed to water taken from either of the twoTraunsee stations and from a control station located inneighbouring Attersee. Cell-specific photosynthetic activitymeasured by 4-h in vitro incubations revealed no significantdifference among the three stations investigated. Growthrates of the same three Synechococcus spp. strains weremeasured by flow cytometry over several days in thelaboratory. One strain, in particular, was sensitive to watertaken from the contaminated site; growth rate of this strainwas significantly reduced, relative to when exposed to watertaken from the reference station. Taken together, our resultsdemonstrate that picocyanobacteria are highly sensitivebioindicators of contaminant stress. The overall impact ofthe emissions from the industrial outlet on thepicocyanobacteria was, however, relatively minor.  相似文献   

3.
This work validated a burial protocol for in situ testing and presents a robust, repeatable and time-saving technique to measure degraded areas in the sample, i.e. an image analysis method. 1440 specimens of degraded samples have been compiled in a data base. To this end, twenty samples presenting different levels of biodegradability (i.e. PHBV/HV, PLA, PCL, PCL-Starch, paper, PE, PE-Starch) were buried at 4 different locations and then disinterred at 4, 6, 9, 12, 18, and 24-month intervals. The biodegradation levels of these samples were determined by computing weight and area loss. Weight loss was measured after careful cleaning, whereas area loss was quantified using image analysis. Image analysis gives reliable information on visual pollution while only requiring a rudimentary and thus quicker cleaning of the samples.  相似文献   

4.
Risk assessment of two sections (I and II) of an old landfill (ALH) in Styria (Austria) in terms of reactivity of waste organic matter and the related potential of gaseous emissions was performed using conventional parameters and innovative tools to verify their effectiveness in practice. The ecological survey of the established vegetation at the landfill surface (plant sociological relevés) indicated no relevant emissions over a longer period of time. Statistical evaluation of conventional parameters reveals that dissolved organic carbon (DOC), respiration activity (RA4), loss of ignition (LOI) and total inorganic carbon (TIC) mostly influence the variability of the gas generation sum (GS21). According to Fourier Transform Infrared (FT-IR) spectral data and the results of the classification model the reactivity potential of the investigated sections is very low which is in accordance with the results of plant sociological relevés and biological tests. The interpretation of specific regions in the FT-IR spectra was changed and adapted to material characteristics. Contrary to mechanically–biologically treated (MBT) materials, where strong aliphatic methylene bands indicate reactivity, they are rather assigned to the CH vibrations of plastics in old landfill materials. This assumption was confirmed by thermal analysis and the characteristic heat flow profile of plastics containing landfill samples. Therefore organic carbon contents are relatively high compared to other stable landfills as shown by a prediction model for TOC contents based on heat flow profiles and partial least squares regression (PLS-R). The stability of the landfill samples, expressed by the relation of CO2 release and enthalpies, was compared to unreactive landfills, archeological samples, earthlike materials and hardly degradable organic matter. Due to the material composition and the aging process the landfill samples are located between hardly degradable, but easily combustible materials and thermally resistant materials with acquired stability.  相似文献   

5.
In this study, several emerging compounds of concern in waste water are identified and discussed in relation to data available on their sources and mass flows in urban waters. In most western European situations, the highest contributions to the mass flow of xenobiotics to the urban water cycle stems from household and services applications (e.g. personal care compounds, pharmaceuticals, steroid hormones, flame retardants, fluorinated detergents etc.) as well as building and constructing environments (e.g. flame retardants, plasticizers, UV-blockers and biocides). The contribution from industrial point sources such as incineration industries e.g. coal, tar, steel and gas production (such as PAHs, PCBs, dioxins, etc.) and chemical industries are decreasing in relevance in terms of input and are hence currently of more local relevance only. In relation to identified compounds, this paper considers current data availability and its use in a range of management strategies for the mitigation or controlling of xenobiotics ‘at source’. However it also identifies major knowledge gaps relating to the behaviour and fate of organic pollutants in various sectors of the urban water cycle including stormwater management, bank- and soil infiltration as well as underground and soil passage of polluted waters. It is also discussing the major sources of a range of current day urban pollutants. The paper considers the sources of emerging pollutants in a qualitative way.  相似文献   

6.
A field ammonia (NH3) release experiment and open top chambers containing moorland monoliths continuously fumigated with NH3 or sprayed with NH4Cl were used to assess the potential for using 15N values in determining the area of influence around a point NH3 emission source. 15N values are being increasingly used as environmental tracers and we tested the hypothesis that the 15N signal from an NH3 emission source is observable in nearby vegetation. Using modified monitoring devices, atmospheric NH3 concentrations were found to decrease with distance from source, with 15N values also reflecting this trend, producing a signal shift with changing concentration. Open top chamber studies of 15N values of Calluna vulgaris (L.) Hull indicated a correlation with deposition treatments in current year shoots. Analysis of Calluna shoots from the NH3 release showed a similar trend of 15N enrichment. Significant linear correlations between 15N and percent N in plant material were found, both in the controlled conditions of the open top chambers and at the NH3 release site, illustrating the possible use of this technique in N deposition biomonitoring.  相似文献   

7.
Journal of Material Cycles and Waste Management - The excessive consumption of single-use plastic bags in recent years has fueled plastic pollution leading to considerable adverse consequences for...  相似文献   

8.
Palm oil mill effluent (POME) is the liquid waste from palm oil mills, and is generally treated using open lagoon technology. However, open lagoons can also be combined with more environmentally friendly technologies. In this study, the analytic hierarchy process (AHP) was used to determine the best combination open lagoon of technology (COLT) for POME treatment. The selected criteria were benefit, opportunity, risk, and cost, with sub-criteria further determined based on these criteria. The sub-criteria were revenue, greenhouse gas reduction, employment absorption, corporate social responsibility, co-processing, environmental risk, marketing risk, technology reliability, investment cost, operation and maintenance cost, and opportunity cost. The alternatives were COLT-composting for fertilizer purpose and COLT-biogas for energy generation purpose. Calculation and analysis was performed on questionnaire data using Expert Choice®. COLT-composting proved to be the superior COLT using tentative performance of alternative in this research, with advantages in benefit, opportunity, and risk. The priority weight for COLT-composting was 0.636. Sensitivity analysis was performed by changing criteria priorities. For COLT-biogas to be considered better than COLT-composting, the cost would need to be weighted more than 0.954.  相似文献   

9.
Journal of Material Cycles and Waste Management - The extraction of unsustainable natural resources like sand and topsoil for construction is disturbing ecological balance, affecting local...  相似文献   

10.
Journal of Material Cycles and Waste Management - E-waste is becoming a concern due to its toxic content and serious pollution effect. Many studies have focused on the detrimental impacts of...  相似文献   

11.
Ionic liquids (IL)s have been recognized as ‘green’ alternatives to the organic solvents in a range of synthesis, catalysis and electrochemistry due to their unique chemical and physical properties. In this investigation, a series of organosoluble, thermally stable and optically active hydroxyl-containing poly(amide–imide)s (PAI)s were prepared via polycondensation reaction of an aromatic diamine, 3,5-diamino-N-(4-hydroxyphenyl)benzamide (4), and different chiral amino acid-based diacids (3a–3e) in the presence of molten tetrabutylammonium bromide as a molten IL and triphenyl phosphite under classical heating method. This process is safe and green since toxic and volatile organic solvents such as N-methylpyrrolidone (NMP) and N,N′-dimethylacetamide (DMAc) were eliminated. The resulting new polymers were obtained in good yields with inherent viscosities ranging between 0.23 and 0.54 dL g?1 and were characterized by Fourier transform infrared spectroscopy, specific rotation, powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis, elemental analysis, and in some cases by 1H-NMR techniques. The FE-SEM micrographs and XRD showed that the synthesized PAIs were nanostructured and amorphous polymers. The effect of ultrasonic irradiation on the size of polymer particles was also investigated and the results showed that the size of polymer nanoparticles after ultrasonication became smaller than the size of them, before ultrasonic radiation. All of the polymers were readily soluble in many organic solvents such as N,N′-dimethyl sulfoxide, DMAc and NMP.  相似文献   

12.
The aim of the present study is to study the effect of γ-dose rate on the biodegradation of γ-sterilized polyolefins. Films of isotactic polypropylene, high density polyethylene and ethylene-propylene (EP) copolymer were sterilized under γ-radiation with doses of 10 and 25 kGy. Two different 60Co sources were used with dose rate 600 and 780 Gy h−1. Neat and sterilized samples were incubated in compost and fungal culture environments. The changes in functional groups, surface morphology and intrinsic viscosity in polymer chains were characterized by FT-IR spectroscopy, SEM and viscometric measurements, respectively. It was observed that both γ-degradation and biodegradation processes depend on the dose rate of γ-source. It was found that the biodegradation of γ-sterilized polyolefins in composting and microbial culture environments increased with decreasing the γ-dose rate.  相似文献   

13.
Pharmaceuticals are designed to be bioactive and therefore are among the most important chemical compounds manufactured. In recent years pharmaceuticals have been detected in a range of environment compartments, with concerns raised that they may impose a risk to both humans and environmental organisms. To support informed management of any associated risks, knowledge about their substance flows is indispensable. However, little is known about sources and attributable substance flows with regard to the use of human pharmaceuticals. Often data available on a national level are used to judge local or regional situations and to calculate expected concentrations. In this paper, computations on the use of active pharmaceutical ingredients (APIs) of drugs used in human medicine at the local, regional and national levels were conducted. Different data sources were used and raw-data were scaled up- or downwards and compared. Results of this analysis indicated that hospitals are, by far, minor sources of pharmaceuticals to the aquatic environment in comparison to non-point emissions from households. Differences in flows at the local, regional and national scales are also identified.  相似文献   

14.
In the Federal Republic of Germany a working party has developed recommendations for dealing with the dioxin problems posed by waste incineration. According to these recommendations limit values for dioxin emissions are neither necessary nor practical. However, from the point of view of preventive environmental protection, dioxin emissions should be further reduced as far as is possible with present-day technology. The TA Luft (Technical Instructions for Maintaining Air Quality) contains stipulations and advice on this. The most significant of the solid residues from waste incinerators are the filter ashes as they have a high dioxin content. The working party of Under (states) has compiled a catalogue of recommendations for the disposal of filter ashes. The transport of solid residues from solid waste incinerators is controlled under the Abfallgesetz (Waste Act) and regulations passed in connection with this act and under the Gefahrgutverordnung Strasse—GGVS (Regulation on the transport of dangerous freight by road). The latter stipulates at what level of dioxin certain transport conditions must be respected. The new Gefahrstoffverordnung-GefStoffV (Regulation on dangerous substances) prohibits substances containing dioxin in concentrations above a certain level from being placed on the market. It does not apply to residues from solid waste incinerators.  相似文献   

15.
Mexico is currently facing a crisis in the waste management field. Some efforts have just commenced in urban and in rural settlements, e.g., conversion of open dumps into landfills, a relatively small composting culture, and implementation of source separation and plastic recycling strategies. Nonetheless, the high heterogeneity of components in the waste, many of these with hazardous properties, present the municipal collection services with serious problems, due to the risks to the health of the workers and to the impacts to the environment as a result of the inadequate disposition of these wastes. A generation study in the domestic sector was undertaken with the aim of finding out the composition and the generation rate of household hazardous waste (HHW) produced at residences. Simultaneously to the generation study, a socioeconomic survey was applied to determine the influence of income level on the production of HHW. Results from the solid waste generation analysis indicated that approximately 1.6% of the waste stream consists of HHW. Correspondingly, it was estimated that in Morelia, a total amount of 442ton/day of domestic waste are produced, including 7.1ton of HHW per day. Furthermore, the overall amount of HHW is not directly related to income level, although particular byproducts do correlate. However, an important difference was observed, as the brands and the presentation sizes of goods and products used in each socioeconomic stratum varied.  相似文献   

16.
There is increasing concern about landfilling of biodegradable wastes. Therefore, biological treatment processes such as composting and biogasification have been considered as alternative strategies for managing those wastes. In this work, life cycle assessment was employed to compare the environmental impacts of landfilling, composting, and biological treatment of municipal solid waste in S?o Paulo City, Brazil. Energy consumption, recovered resources, and emissions to air and water were quantified and analyzed in terms of their potential contribution to global warming, acidification, and nutrient enrichment impact. The results demonstrated that processes that require high levels of energy consumption, such as wastewater treatment, play an important role in the outcome of environmental impact potentials. It was found that the landfilling of all waste is generally the worst strategy from an environmental point of view. However, significant reductions in the resulting impacts can be accomplished through biogasification and composting of the biodegradable fraction. Regarding composting, the application of a biofilter for gas treatment reduced significantly the gaseous emissions.  相似文献   

17.
Melt-pressed films of polycaprolactone (PCL) and poly(lactic acid) (PLA) with processing additives, CaCO3, SiO2, and erucamide, were subjected to pure fungal cultures Aspergillus fumigatus and Penicillium simplicissimum and to composting. The PCL films showed a rapid weight loss with a minor reduction in the molecular weight after 45 days in A. fumigatus. The addition of SiO2 to PCL increased the rate of (bio)erosion in A. fumigatus and in compost. The use of a slip additive, erucamide, was shown to modify the properties of the film surface without decreasing the rate of bio(erosion). Both the rate of weight loss and the rate of molecular weight reduction of PCL increased with decreasing film thickness. The addition of CaCO3 to PLA significantly reduced the thermal degradation during processing, but it also reduced the rate of the subsequent (bio)degradation in the pure fungal cultures. PLA without additives and PLA containing SiO2 exhibited the fastest (bio)degradation, followed by PLA with CaCO3. The degradation of the PLA films was initially governed by chemical hydrolysis, followed by an acceleration of the weight change and of the molecular weight reduction. PLA film subjected to composting exhibits a rapid decrease in molecular weight, which then remains unchanged during the measurement period, probably because of crystallization.  相似文献   

18.
Lindberg  S. E.  Brooks  S.  Lin  C-J.  Scott  K.  Meyers  T.  Chambers  L.  Landis  M.  Stevens  R. 《Water, Air, & Soil Pollution: Focus》2001,1(5-6):295-302
We have measured total gaseous mercury concentrations(Hg°) at Point Barrow, Alaska since September 1998 in aneffort to determine the geographic extent and reaction mechanismof the so-called mercury depletion events (MDE) previouslyreported in the high Arctic at Alert, Canada. Hg° has beensampled now for nearly 2 years at Barrow. In September, 1999, webegan making the first automated measurements of reactive gaseousmercury (RGM) attempted in the Arctic, along with measurements ofHg accumulation in snowpack to determine the fate of the depleted Hg°. During the fall and early winter, Hg°and RGM exhibit only minor variation, Hg° remaining within10% of global background, near 1.6–1.8 ng m-3. The MDEperiods are quite different, however; within days of Arcticsunrise in January, Hg° exhibits major variations from themean, rapidly dropping as low as 0.05 ng m-3 and then cyclingback to typical levels, sometimes exceeding global background. These events continue throughout Arctic spring, then end abruptlyfollowing snowmelt, in early June. Prior to Arctic sunrise, RGMremains near detection (<2 pg m-3), but after sunriseincreases dramatically (to levels as high as 900 pg/m3) insynchrony with the depletion of Hg°. Both phenomenaexhibit a strong diel cycle, in parallel with UV-B. We concludethat MDE's involve rapid in-air oxidation of Hg° to aspecies of RGM by photochemically-driven reactions, probablyinvolving the same reactive bromine and chlorine compoundsinvolved in ozone destruction. Sharp increases in Hg in thesurface snowpack after sunrise coincident with periods of peakRGM suggest surface accumulation of the RGM by dry deposition.  相似文献   

19.
The results of an investigation aimed at evaluation of the biodegradability of blends of poly(-caprolactone) (PCL) with poly(ethylene terephthalate) (PET) as the major component are reported. Specimens of the blends, as melt extruded films and/or powders, were submitted to degradation tests under different environmental conditions including full-scale composting, soil burial, bench-scale accelerated aerobic degradation, and exposure to axenic cultures and esterolytic enzymes. Indications have been gained that blending in the melt gives rise to insertion of PCL segments in the PET chain. Copolymers thus attained acted as macromolecular compatibilizers, allowing for a complete miscibility of PCL and PET. The biodegradation detected on the blend samples was, however, well below the values expected from chemical composition and behavior of individual homopolymers under the same environmental conditions. The presence of PET as the major component in PET/PCL blends apparently reduces the propensity of PCL to be degraded, at least in the investigated composition range. The degradation data collected under different environmental conditions indicate that the full-scale composting system is the most efficient among the tested degradation procedures.  相似文献   

20.
This paper presents and critically analyses the current waste electrical and electronic equipment (WEEE) management practices in various countries and regions. Global trends in (i) the quantities and composition of WEEE; and (ii) the various strategies and practices adopted by selected countries to handle, regulate and prevent WEEE are comprehensively examined. The findings indicate that for (i), the quantities of WEEE generated are high and/or on the increase. IT and telecommunications equipment seem to be the dominant WEEE being generated, at least in terms of numbers, in Africa, in the poorer regions of Asia and in Latin/South America. However, the paper contends that the reported figures on quantities of WEEE generated may be grossly underestimated. For (ii), with the notable exception of Europe, many countries seem to be lacking or are slow in initiating, drafting and adopting WEEE regulations. Handling of WEEE in developing countries is typified by high rate of repair and reuse within a largely informal recycling sector. In both developed and developing nations, the landfilling of WEEE is still a concern. It has been established that stockpiling of unwanted electrical and electronic products is common in both the USA and less developed economies. The paper also identifies and discusses four common priority areas for WEEE across the globe, namely: (i) resource depletion; (ii) ethical concerns; (iii) health and environmental issues; and (iv) WEEE takeback strategies. Further, the paper discusses the future perspectives on WEEE generation, treatment, prevention and regulation. Four key conclusions are drawn from this review: global amounts of WEEE will continue unabated for some time due to emergence of new technologies and affordable electronics; informal recycling in developing nations has the potential of making a valuable contribution if their operations can be changed with strict safety standards as a priority; the pace of initiating and enacting WEEE specific legislation is very slow across the globe and in some cases non-existent; and globally, there is need for more accurate and current data on amounts and types of WEEE generated.  相似文献   

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