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1.
As a result of forcing the energy utilization from biomass, the amounts of combustion residues, especially woodash, are growing. For a sustainable and ecologically effective closed-cycle economy, the knowledge of the chemical composition of the ashes is necessary. The matrix wood ash is very complex, due to the great number of constituents in different concentrations. Therefore it is important to develop a combination of analytical methods for the complete detection of nutrients and heavy metals in wood ash. Ashes from different heating plants (wood chips-, bark-and sawdust combustion systems) were analysed with X-ray methods as well as with acid-digestion in combination with atomic spectrometry detection. The results were compared and checked for their plausibility by statistical methods and material balances for the inorganic elements from the biomass to the ash fractions. As a result of this evaluation astandard method is recommended for the analysis of wood ash. This method consists of a combination of dry (X-ray) analysis (for the elements Si, Ca, Mg, K, P, Al, Fe, Mn) and fluid analysis (for the detection of heavy metals).  相似文献   

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The aim of this work is to clarify if there is a correlation between fuel and its organic combustion products. To acquire homogenous data sets for our investigations, we analysed only the measurements of the “Forschungsstelle für Brandschutztechnik” at the University of Karlsruhe. All compounds with a similar structure were grouped and structural indices were ascribed to them. This also made it possible to obtain information about the frequency of occurrence of a set of substances in fire smoke. The kind of analytical measurements used by this institute provided no or only little information about inorganic compounds, highly volatile substances like acrolein or vinyl chloride, and very poorly volatile substances (e.g. polycyclic aromatic hydrocarbons). We found that benzene, methylbenzene, ethenylbenzene and ethylbenzene are always present in fire smoke. The formation of these typical compounds is described by a model. Aside from these compounds which are typically related to the smoke from fires, substances are always observed which are typical for a distinct fuel. Many compounds which are expected to be in the smoke are highly carcinogenic. Therefore, it is necessary for people with a high exposure to the smoke of fires, e.g. firemen, to protect themselves efficiently. In order to obtain more information about the risks to health of fire smoke, toxicological investigations will be necessary.  相似文献   

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Surfaces of many sports fields, playgrounds and paths in Germany are covered with red slag ?Kieselrot”. Kieselrot is extremely high contaminated by polychlorinated dibenzodioxines and dibenzofurans. Mean PCDD/F-concentration in surface layers of 35 locations in Hessen is 45 500 ng I-TE/kg. PCDD/F-contents range from 1 000 to 250 ng I-TE/kg within 10 cm under surface layers and from 6 000 to 600 ng I-TE/kg in top soils of three metres wide peripheral areas. Concentration in subsoils is a function of depth (n=18, r=?0,741), concentration in topsoils of peripheral areas is a function of distance from large sports fields (n=14, r=?0,881) or small sportsfields (n=23, r=?0,742), respectively. A 15 metres wide and 10 centimetres deep peripheral area contains 0,8 g I-TE PCDD/F. The pollution of surroundings and further observations indicate that ?Kieselrot-areas” must be regarded as important dioxin sources.  相似文献   

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A soil, containing 2.8% organic carbon and a high concentration (76.4%) of small particles (<63 μm), and which had been contaminated over a long period of time by galvanic waste waters (Ni, Cu) and lead wastes, was subjected to detailed analysis and subsequently treated with various extracting solutions in order to remove the heavy metals. For this purpose, representative samples containing 114 mg kg?1 Cu, 1151 mg kg?1 Ni and 366 mg kg?1 Pb were treated with amino acids and solutions containing other complexing agents, as well as with diluted acids, in order to compare the relative effectiveness of these solutions. Satisfactory metal extractions were only achieved by the use of diluted mineral acids, notably hydrochloric acid, which released more than 90% of the nickel and approximately 80% of the copper and lead from the soil. The results obtained with weak complexing agents such as tartaric acid (0.07–2.9%, 24 h) and amino acids (0.01–36%, 24h) were worse. For reprocessing of the hydrochloric acid solutions, a direct precipitation of the heavy metals in their hydroxide forms and selective separation with N-acylthiourea modified polysiloxanes were carried out.  相似文献   

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Soils on sites of former coking and manufactured gas plants as well as on those of blast furnaces are frequently contaminated with cyanides (CN). For assessing the possible risk arising from these hazardous compounds, it is necessary to analyze a considerable number of samples quickly as well as at low costs. Fourier transform infrared (FTIR) spectroscopy has the advantage of being much easier in handling compared to conventional wet-chemical methods for analyzing cyanides. For testing FTIR spectroscopy in the application mentioned above, pure cyanide compounds as well as contaminated purifier waste, blast furnace sludge, and spiked soils were investigated by the reflexion and the transmission techniques. Applicability of the attenuated total reflexion (ATR) technique was limited, since the absorption bands of the crystal used (diamond) overlapped in the range of the cyanide-specific absorption. Although the environmental samples investigated have unfavorable optical properties, results obtained by the transmission technique (KBr pressed pellets) were much better than those obtained by the reflexion technique. Pure cyanide compounds could be distinguished by their IR spectra because their absorption bands of the cyanide-valence vibration differed in position, shape and intensity. The soil matrix did not interfere with either the intensity or the shape and position of the absorption maxima, as concluded from the IR spectra of spiked soil samples. Applying the transmission technique, cyanides are detected at concentrations larger than 500 mg kg?1 CN. However, the signal was low when the cyanide concentration was below 1,000 mg kg?1 CN. The FTIR spectroscopy is capable of detecting cyanide compounds in soils and industrial wastes. Additionally, the method provides information about the cyanide species, which is important in toxicological assessments. FIIR spectroscopy is a suitable method for a first survey and environmental assessment of cyanide contaminated areas.  相似文献   

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Kaolin W from Lohrheim (51% Illite, 31% Kaolinite, 18% Quarz, no Carbon) was loaded with various amounts of heavy metal ions (0.11–6.0 mmol/100g Cu, Ni, Cd) from their nitrate solutions. In the next step the release of the bound metals was tested with or without aminoacids (penicillamine and histidine) in solutions of weak acidity or alkalinity. It was found an evident influence of the aminoacids to the metal release in dependence of metalcoating, metal-aminoacid-ratio and experimental pH. Especially in alkali environment a multiplication of the copper release (to a factor of 39 (pen) or 27 (his)) was observed. An increased nickel (factor 53) and cadmium release (factor 4.5) was found with histidine. In this cases 80 to 100% of the heavy metals were removed from the clay-mineral-surface.  相似文献   

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With the aid of the Hamburg proton micro-probe, we examined the concentration of mercury in sea eagle feathers collected over the course of several decades in the Mecklenburg-Vorpommern area. Based on the sites where these feathers were collected and the data of these findings, it is possible to get a differential picture of mercury contamination related both temporally and regionally to the mercurial pollution of seed mordants used agriculturally. We compared the concentrations found with a basic “geogenic” contamination which was also to be seen in the feather samples from the last century as detected in museum animal specimens.  相似文献   

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Background, aim, and scope Polycyclic aromatic hydrocarbons (PAH) are important environmental contaminants in the marine environment. The Baltic is known to be significantly contaminated with PAH. The eelpout (Zoarces viviparus) has been used for coastal monitoring in the Baltic. The aim of the present study was to elucidate whether the eelpout can be used to investigate PAH contamination in the Mecklenburg Bight and whether PAH sources may be revealed by the relation of the metabolites. Material and methods PAH metabolites were determined in the bile fluid of eelpout caught in spring 2008 at three sampling locations in the Wismar Bight. Two metabolites were determined by means of HPLC and fluorescence detection. In addition, bile pigments were measured photometrically. Results The concentrations of 1-hydroxypyrene in bile were significantly different at all three sampling locations under investigation. Highest concentrations were found near the city of Wismar with a mean value of 1086?ng/ml. Concentrations for individual fish ranged from <22.5 to 3317?ng/ml 1-hydroxypyrene. Concentrations of 1-hydroxyphenanthrene were lower and ranged from 2.1 to 803?ng/ml in individual samples. In fish caught next to the city of Wismar a mean value of 96?ng/ml 1-hydroxyphenanthrene was calculated. Discussion In the light of substantial anthropogenic contamination in this area caused by harbor, shipyards and shipping traffic, high values of 1-hydroxypyrene found in eelpout near the city of Wismar appear to be very plausible. Furtheron, the 1-hydroxypyrene results are in accordance to literature data. 1-Hydroxyphenantrene in eelpout bile was found in higher concentrations compared to earlier investigations. Spatial differences in the relation of the two metabolites may indicate a local source of PAH. Recommendations and perspectives PAH metabolites are useful parameters for monitoring the PAH pollution of fish like eelpout. Additional information regarding potential PAH sources can be gained from the relations of individual metabolites.  相似文献   

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Volatile organic compounds were determined in stack-gas emissions from the residential burning of brown-coal briquets using adsorptive enrichment on hydrophobic adsorbents, thermal desorption and capillary-gas chromatographic analysis. 152 compounds were identified and quantified. Quantitative emission factors of the identified individual compounds were determined in relation to the amount of the fuel used. These factors permit assessment of the pollution of the city of Leipzig with volatile organic compounds resulting from the burning of indigenous lignite.  相似文献   

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The pHstat-procedure is a method to examine the pH-dependent mobilisation of heavy metals and other pollutants from solids. The metals in such extracts are usually determined by atomic absorption (AAS) or by emission spectrometry (ICP-OES). The obtained values present the total amount of mobilized metals. A statement concerning the effect-oriented true toxicity of the extract, respective of the examined solid, is not possible. A combined effect-oriented procedure, such as a the bioaluminescence-inhibition test with luminescence bacteria enables a precise statement about the ecotoxicity of solids. A variation of the inhibition test (addition of EDTA) indicates the main binding forms of heavy metals and the part of inhibition caused by organic material.  相似文献   

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For the first time it is reported on the residues of chlorinated bis-(dichloropropyl) ethers in fish from the Elbe-river, and their octanol/water partition coefficients.  相似文献   

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Simple biotests are frequently used for the ecotoxicological assessment of waste water. Unfortunately, and not too rarely, effects are detected and the question concerning water-polluting substances has to be answered. The latter are enriched by solid phase extraction (SPE), then isolated and fractioned by thinlayer chromatography using automatic multiple development (AMD). One strip of the DC-plate is separated and used without further atterations for the biological detection with microorganisms (Bacillus subtilis, luminous bacteria). With this system, toxic bands can be identified. From the other part of the DC plate, an UV-spectrum can be taken of the toxic bands using a DC scanner. Subsequently, the corresponding bands are scratched out and the toxic substance is eluted and analysed with infrared spectroscopy. The infrared spectrum can be characterised by comparing it with reference spectra. In this submitted work, a concept is presented with an example of a “nipple rubber” eluate. It shows that this rubber article liberates a vulcanization accelerator, 2-mercaptobenzothiazole.  相似文献   

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This paper reflects various personal experiences of the author over the last years, concerning ecotoxicological test development and regulatory-type evaluations of the environmental risk assessment of high production volume chemicals.  相似文献   

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