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1.

Purpose  

Industrial wastewater flow caused operational difficulties in the wastewater treatment plant in Debrecen, Hungary. Bioaugmentation was successfully applied to maintain effluent quality in the periods when wastewater of high starch content was accepted, but, at the end of 2008, the nitrification capacity of the plant decreased considerably due to improperly pre-treated pharmaceutical wastewater.  相似文献   

2.
The occurrence of magnetotactic bacteria (MTB) on a Tunisian marine coast exposed to heavy metals pollution (Sfax, Gulf of Gabès, Mediterranean Sea) was investigated. The MTB population of this Southern Mediterranean coast was compared to the MTB populations previously investigated on the French Northern Mediterranean coast. A dominant MTB coccus morphotype was observed by microscopy analysis. By pyrosequencing technology, the analysis of the 16S ribosomal RNA (rDNA) revealed as much as 33 operational taxonomic sequence units (OTUs) close to sequences of MTB accessible in the databases. The majority were close to MTB sequences of the “Med group” of α-Proteobacteria. Among them, a dominant OTU_001 (99 % of the MTB sequences) affiliated within the Magnetococcales order was highlighted. Investigating the capacities of this novel bacterium to be used in bioremediation and/or depollution processes could be envisaged.  相似文献   

3.
Sorption of lead in soil as a function of pH: a study case in México   总被引:3,自引:0,他引:3  
Reactions of lead sorption onto soil are largely affected by properties and composition of soil and its solution. In this study, the lead sorption onto regosol eutric soil from Francisco I. Madero, Zacatecas, Mexico is evaluated at different pH values. Soil samples were suspended in lead solutions of 10, 25, 50, 100, 150, 200, 300, and 400 mg/l (as Pb(NO3)2). The pH was adjusted at 2, 3, 4, and 5.5 with nitric acid for each of the lead solution concentrations. In all the cases the ionic strength was I=0.09 M with calcium nitrate. The solid-liquid-ratios were fixed in 1:100 and 1:200 g/ml. The results show that lead sorption increases when pH increases. Experimental isotherms were adjusted by both Langmuir and Freundlich models. The Langmuir affinity parameter, K, indicates that the lead sorption capacity of Francisco I. Madero soils is largely perceptible to pH changes.  相似文献   

4.
ABSTRACT

The literature on hydrocarbon remediation with basidiomycetes was reviewed. Two ecological groups are considered for bioremediation, the saprotrophic basidiomycetes (white-rot and brown-rot fungi) and the ectomycorrhizal basidiomycetes. A remarkable capacity of basidiomycetes for in vitro degradation of simple and recalcitrant hydrocarbons, such as PAH, persistent organic pollutants (POPs), halogenated HC, aromatic HC and phenols, explosives and dyes was reported for many species. However, there is a need for more studies on the practical feasibility of field applications with basidiomycetes.  相似文献   

5.
Safe and sufficient quantity of water is necessary for a healthy growth of human beings. The gap between water demand and available water supply is increasing day by day. Proper sanitation, especially decentralized approach, can solve the problem of water supply and wastewater management and that can be done by reuse of greywater. Typically, from a household, greywater (GW) flow is around 65 % of the total wastewater flow. Further light greywater is around 50 % of the total GW. Hence, GW has a high potential for recycle and reuse. The aim of this article is to reveal the present state of art in GW treatment and to identify the further scope for research. Present article contains a review on per capita GW generation, GW characteristics, and its treatment. Around 22 treatment systems comprising different treatment processes are discussed in detail for removal efficiency of pollutants, effluent concentrations and their compliance with wastewater reuse guidelines and standards. Constructed wetland and filtration were found efficient in the removal of most of the reuse parameters compared to other technologies. Anaerobic followed by aerobic system with post-disinfection unit may be a sustainable option for GW treatment for reuse. There is a need to develop the technologies for GW treatment at household level to increase the reuse practises at grass root level. Further, there is need of development of flow diagram with different technologies by targeting the type of reuse (flushing, gardening, agriculture, etc.).  相似文献   

6.
Biochar is produced by pyrolysis of biomass residues under limited oxygen conditions. In recent years, biochar as an amendment has received increasing attention on composting and soil remediation, due to its unique properties such as chemical recalcitrance, high porosity and sorption capacity, and large surface area. This paper provides an overview on the impact of biochar on the chemical characteristics (greenhouse gas emissions, nitrogen loss, decomposition and humification of organic matter) and microbial community structure during composting of organic wastes. This review also discusses the use of biochar for remediation of soils contaminated with organic pollutants and heavy metals as well as related mechanisms. Besides its aging, the effects of biochar on the environment fate and efficacy of pesticides deserve special attention. Moreover, the combined application of biochar and compost affects synergistically on soil remediation and plant growth. Future research needs are identified to ensure a wide application of biochar in composting and soil remediation.
Graphical abstract ?
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7.
Fuel use limitations present a dilemma to both suppliers and users in that fuel with high sulfur content may be prohibited, even though during much of the year meteorological conditions may provide sufficent dispersion to maintain acceptable air quality levels. To make most efficient use of available fuels, a system of varying emissions according to atmospheric parameters is suggested. Objective forecasts of meteorological conditions in terms of dispersion effects can be used to monitor fuel use according to the atmosphere’s ability to disperse pollutants successfully.  相似文献   

8.
The present paper examines the use of zinc isotopes as tracers of atmospheric sources and focuses on the potential fractionation of Zn isotopes through anthropogenic processes. In order to do so, Zn isotopic ratios are measured in enriched ores and airborne particles associated with pyrometallurgical activities of one of the major Pb–Zn refineries in France. Supporting the isotopic investigation, this paper also compares morphological and chemical characteristics of Zn particles collected on dry deposition plates (“environmental samples”) placed within a 5 km radius of the smelter, with those of Zn particles collected inside the plant (“process samples”), i.e. dust collected from the main exhaust system of the plant. To ensure a constant isotopic “supply”, the refinery processed a specific set of ores during the sampling campaigns, as agreed with the executive staff of the plant. Enriched ores and dust produced by the successive Zn extraction steps show strong isotope fractionation (from ?0.66 to +0.22‰) mainly related to evaporation processes within the blast furnaces. Dust from the main chimney displays a δ66Zn value of ?0.67‰. Application of the Rayleigh equation to evaluate the fractionation factor associated with the Zn vapor produced after a free evaporation gives a range of αore/vapor from 1.0004 to 1.0008. The dry deposits, collected on plates downwind of the refinery, display δ66Zn variations of up to +0.7‰. However, it is to be noted that between 190 and 1250 m from the main chimney of the refinery, the dry deposits show a high level of large (>10 μm) Zn, S, Fe and O bearing aggregates characterized by positive δ66Zn values (+0.02 to +0.19‰). These airborne particles probably derive from the re-suspension of slag heaps and local emissions from the working-units. In contrast, from 1720 to 4560 m, the dry deposits are comprised of small (PM10) particles, including spherical Zn-bearing aggregates, showing negative δ66Zn values (?0.52 to ?0.02‰). Our results suggest that the source of the distal dry fallouts is the main chimney plume, whose light Zn isotopic signature they preserve. Based on Zn isotopic analysis in combination with morphological and chemical characteristics of airborne particles, the present study suggests the traceability of smelter dusts by Zn isotopes.  相似文献   

9.
There is a recent increase in the interest of designing high-performance photocatalysts using graphene-based materials. This review gathers some important aspects of graphene?CTiO2, graphene oxide?CTiO2, and reduced graphene oxide?CTiO2 composites, which are of especial relevance as next generation photocatalysts. The methods used for the preparation of these materials, the associated mechanistic fundamentals, and the application of graphene-based composites on the photocatalytic degradation of pollutants are reviewed. Some structural, textural, and chemical properties of these materials and other photo-assisted applications, such as hydrogen production from water splitting and dye-sensitized solar cells, are also briefly included.  相似文献   

10.
Environmental Science and Pollution Research - The total cultivated area in Brazil reached to 62 million ha in 2018, with the predominance of genetically modified soybean and corn (36 and 17...  相似文献   

11.
The role of vertical atmospheric transport (VAT) for a winter ozone episode (January 1988) in the Alps, observed both on the mountain crest (3580 m asl) and in the lee of the Alps (209 m asl), is investigated. Numerical simulations were carried out with a doubly nested mesoscale model (14 km horizontal resolution), characterised by a refined orography scheme. A comparison between the modelled vertical profiles with features observed in the aerological soundings over Payerne indicated that the model is able to reproduce the fold in the Alps down to 650 hPa. Frictional processes are found to be responsible for the fragmentation of the lower parts of the fold when it is advected over the mountains, thus enhancing ozone concentrations at the mountain crest with likely cross-tropopause mixing. Vertically propagating gravity waves and strong mesoscale vertical winds (nordfoehn) are responsible for the further downward transport of ozone-rich air to the lower troposphere. This mechanism leads to ozone concentrations up to 70 ppb(v) in the leeside. The study is important because tropospheric ozone trends in the lee of the Alps have been inferred, in the past, from ozone peaks associated with such nordfoehn conditions. It is now shown that nordfoehn may entrain air which has been recently exchanged across the tropopause.  相似文献   

12.
Abstract

The impacts of biodiesel on gaseous and particulate matter (PM) emissions of a JP-8–fueled T63 engine were investigated. Jet fuel was blended with the soybean oil-derived methyl ester biofuel at various concentrations and combusted in the turbine engine. The engine was operated at three power settings, namely ground idle, cruise, and takeoff power, to study the impact of the biodiesel at significantly different pressure and temperature conditions. Particulate emissions were characterized by measuring the particle number density (PND; particulate concentration), the particle size distribution, and the total particulate mass. PM samples were collected for off-line analysis to obtain information about the effect of the biodiesel on the polycyclic aromatic hydrocarbon (PAH) content. In addition, temperature-programmed oxidation was performed on the collected soot samples to obtain information about the carbonaceous content (elemental or organic). Major and minor gaseous emissions were quantified using a total hydrocarbon analyzer, an oxygen analyzer, and a Fourier Transform IR analyzer. Test results showed the potential of biodiesel to reduce soot emissions in the jet-fueled turbine engine without negatively impacting the engine performance. These reductions, however, were observed only at the higher power settings with relatively high concentrations of biodiesel. Specifically, reductions of ~15% in the PND were observed at cruise and takeoff conditions with 20% biodiesel in the jet fuel. At the idle condition, slight increases in PND were observed; however, evidence shows this increase to be the result of condensed uncombusted biodiesel. Most of the gaseous emissions were unaffected under all of the conditions. The biodiesel was observed to have minimal effect on the formation of polycyclic aromatic hydrocarbons during this study. In addition to the combustion results, discussion of the physical and chemical characteristics of the blended fuels obtained using standard American Society for Testing and Materials (ASTM) fuel specifications methods are presented.  相似文献   

13.
The effect of buildings on the dry deposition of dust particles was investigated in Be'er-Sheva, a desert city with about 140,000 inhabitants in southern Israel, and at two reference points in the surrounding rural area. The mineral and chemical composition of dust sampled at all sites was similar, reflecting the composition of the local loess soil, its likely origin. However, dust deposited in the traps set up in the vicinity of buildings in the city was significantly coarser than the dust which accumulated in similar traps at exposed sites in the countryside. The amount of dust (by weight) in the urban dust traps was on an average more than twice the amount deposited in the rural area. The differences in grain-size distribution and quantity of dust are attributed to the properties of the urban wind field and to various effects of human activity in the city.  相似文献   

14.
Water pollution with pathogenic microorganisms is one of the serious threats to human health, particularly in developing countries. The main objective of this article is to highlight microbial contamination of drinking water, the major factors responsible for microbial contamination, and the resulting health problems in Pakistan. Furthermore, this study will be helpful for researchers and administrative agencies to initiate relevant studies and develop new policies to protect further deterioration of water supply with pathogenic microbes and ensure clean and safe drinking water to the public in Pakistan. In Pakistan, water at the source, in the distribution network, and at the consumer tap is heavily polluted with coliforms and fecal coliforms all over the country. An overview of more than 7,000 water samples reviewed here reveals that an average of over 71 and 58 % samples in the country was contaminated with total coliforms and fecal coliforms, respectively. Drinking water contamination accounts for 20 to 40 % of all diseases in the country, which causes national income losses of Rs 25–58 billion annually (US$0.25–0.58 billion, approximately 0.6–1.44 % of the country’s GDP). Improper disposal of industrial and municipal wastes is the most important factor responsible for water pollution in the country followed by cross-contamination due to old and leaking pipes and lack of water filtration and disinfection facilities. There is an urgent need for emergency steps to stop further deterioration of water quality and improve the existing water quality so as to protect the public from widespread waterborne diseases.  相似文献   

15.
Background, aim, and scope  Pharmaceuticals and their metabolites are detected in the aquatic environment and our drinking water supplies. The need for high quality drinking water is one of the most challenging problems of our times, but still only little knowledge exists on the impact of these compounds on ecosystems, animals, and man. Biological waste water treatment in constructed wetlands is an effective and low-cost alternative, especially for the treatment of non-industrial, municipal waste water. In this situation, plants get in contact with pharmaceutical compounds and have to tackle their detoxification. The mechanisms for the detoxification of xenobiotics in plants are closely related to the mammalian system. An activation reaction (phase I) is followed by a conjugation (phase II) with hydrophilic molecules like glutathione or glucose. Phase III reactions can be summarized as storage, degradation, and transport of the xenobiotic conjugate. Until now, there is no information available on the fate of pharmaceuticals in plants. In this study, we want to investigate the fate and metabolism of N-acetyl-4-aminophenol (paracetamol) in plant tissues using the cell culture of Armoracia rusticana L. as a model system. Materials and methods  A hairy root culture of A. rusticana was treated with acetaminophen in a liquid culture. The formation and identification of metabolites over time were analyzed using HPLC-DAD and LC–MSn techniques. Results  With LC–MS technique, we were able to detect paracetamol and identify three of its metabolites in root cells of A. rusticana. Six hours after incubation with 1 mM of acetaminophen, the distribution of acetaminophen and related metabolites in the cells resulted in 18% paracetamol, 64% paracetamol–glucoside, 17% paracetamol glutathione, and 1% of the corresponding cysteine conjugate. Discussion  The formation of two independently formed metabolites in plant root cells again revealed strong similarities between plant and mammalian detoxification systems. The detoxification mechanism of glucuronization in mammals is mirrored by glucosidation of xenobiotics in plants. Furthermore, in both systems, a glutathione conjugate is formed. Due to the existence of P450 enzymes in plants, the formation of the highly reactive NAPQI intermediate is possible. Conclusions  In this study, we introduce the hairy root cell culture of A. rusticana L. as a suitable model system to study the fate of acetaminophen in plant tissues. Our first results point to the direction of plants being able to take up and detoxify the model substrate paracetamol. These first findings underline the great potential of using plants for waste water treatments in constructed wetlands. Recommendations and perspectives  This very first study on the detoxification of a widely used antipyretic agent in plant tissues again shows the flexibility of plant detoxification systems and their potential in waste water treatment facilities. This study covers only the very first steps of acetaminophen detoxification in plants; still, there is no data on long-term exposure as well as the possible impact of pharmaceuticals on the plant health and stress defense. Long-term experiments need to be performed to follow the fate of acetaminophen in root and leaf cells in a whole plant system, and to evaluate possible usage of plants for the remediation of acetaminophen from waste water.  相似文献   

16.
17.
Soil contamination with anthropogenic metals resulting from biosolid application is widespread around the world. To better predict the environmental fate and mobility of contaminants, it is critical to study the capacity of biosolid-amended soils to retain and release metals. In this paper, nickel adsorption onto a calcareous soil, a lime-stabilized biosolid, and soil–biosolid mixtures (30, 75, and 150 t biosolid/ha) was studied in batch experiments. Sorption experiments showed that (1) Ni adsorption was higher onto the biosolid than the calcareous soil, and (2) biosolid acted as an adsorbent in the biosolid–soil mixtures by increasing Ni retention capacity. The sorption tests were complemented with the estimation of Ni adsorption reversibility by successive applications of extraction solutions with water, calcium (100 mg/L), and oxalic acid (equivalent to 100 mg carbon/L). It has been shown that Ni desorption rates in soil and biosolid-amended soils were lower than 30 % whatever the chemical reagent, indicating that Ni was strongly adsorbed on the different systems. This adsorption/desorption hysteresis effect was particularly significant at the highest biosolid concentration (150 t/ha). Finally, an adsorption empirical model was used to estimate the maximum permissible biosolid application rate using French national guideline. It has been shown that desorption effects should be quantitatively considered to estimate relevant biosolid loadings.  相似文献   

18.
Ginocchio R 《Chemosphere》2000,41(1-2):15-23
A grassland formation has been subjected to pollution generated by the Ventanas copper smelter since 1964 (Puchuncaví Valley, central zone of Chile) with extensive damage to local vegetation and important changes in soil characteristics. The aims of the study were (1) to detect soil parameters that best explain changes observed in plant species richness and abundance and (2) to determine if pollution-derived stresses have also affected regeneration capabilities of plant communities from the soil seed bank. The grassland was quantitatively analysed in terms of physicochemical soil characteristics, plant species diversity and abundance, and soil seed bank species composition and abundance. Results showed that a decrease in total soil nitrogen explained 13% of the changes detected in plant abundance while soil pH and 0.05 M EDTA extractable copper explained 10% and 7%, respectively, of the vegetation change. It was also found that the pollution has already affected plant species regeneration capabilities from the soil seed bank and the microsite distribution of the seeds in soils.  相似文献   

19.
INTRODUCTION: Environmental safe and friendly management and disposal of wastewater sludge is a problem of every treatment plant throughout the world. Bioseparation and dewaterability of raw domestic wastewater sludge were evaluated for proper management and disposal by mycoremediation, i.e., using prior grown 2% (v/v) spore suspension of filamentous fungal (Mucor hiemalis Wehmer) broth inoculation, which were grown in 2% (w/v) solution of malt extract and wheat flour for 48-60 h in orbital shaker. DISCUSSION: Within 2-3 days of treatment application, encouraging results were achieved in total dry solids (TDS), total suspended solid (TSS), turbidity, chemical oxygen demand (COD), specific resistance to filtration (SRF), and pH due to fungal treatment in recognition of bioseparation and dewaterability of wastewater sludge compared to control. The significant reduction of TDS was remarked at fungal biomass (FB) in wheat flour (WF) treatment. The removal of TSS, turbidity, COD, and SRF were observed 96.0%, 99.4%, 92.6%, and 97.6%, respectively, in supernatant at 5 days by FB in WF. The SRF measuring the dewaterability was decreased with maximum (0.26 × 10(-12) mg/kg) equivalent to 95.5% at 2 days in FB in WF also. FB in WF broth is a potential, environmental friendly, comparatively low-cost biological technique which might play the significant role for bioremediation and bioseparation of domestic wastewater sludge. The present technique may bring a dynamic change in treatment of wastewater in future.  相似文献   

20.
The airway irritation of (+)-α-pinene, ozone, mixtures thereof, and formaldehyde was evaluated by a mouse bioassay, in which sensory irritation, bronchoconstriction, and pulmonary irritation were measured. The effects are distinguished by analysis of the respiratory parameters. Significant sensory irritation (assessed from reduction of mean respiratory rate) was observed by dynamic exposure of the mice, over a period of 30 min, to a ca. 22 s old reaction mixture of ozone and (+)-α-pinene from a Teflon flow tube. The starting concentrations were 6 ppm and 80 ppm, respectively, which were diluted and let into the exposure chamber. About 10% ozone remained unreacted (0.4 ppm), <0.2 ppm formaldehyde, <0.4 ppm pinonaldehyde, <2 ppm formic acid, and <1 ppm acetic acid were formed. These concentrations, as well as that of the unreacted (+)-α-pinene (51 ppm), were below established no effect levels. The mean reduction of the respiratory rate (30%) was significantly different (p≪0.001) from clean air, as well as from exposure of (+)-α-pinene, ozone, and formaldehyde themselves at the concentrations measured. Addition of the effects of the measured residual reactants and products cannot explain the observed sensory irritation effect. This suggests that one or more strong airway irritants have been formed. Therefore, oxidation reactions of common naturally occurring unsaturated compounds (e.g., terpenes) may be relevant for indoor air quality.  相似文献   

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