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21.
Oliver Falk Hubertus Wichmann Petra Jopke Christiane Schmidt-Nädler Birthe Matthies Müfit Bahadir Roland Meyer-Pittroff 《Environmental Sciences Europe》2004,16(4):255-261
Aims and Scope
In Germany, 120,000 tons per year of waste edible fats are collected from the catering and the food industry Until recently, these fats have widely been used as a nutritional additive for poultry and other animals fodder. Due to the BSE crisis and some affairs based on dioxins in feeding stuff, waste fats are now barely used as fodder. Currently, these fats substitute fresh vegetable oils in the chemical industry and are used as raw material for the production of biodiesel. Therefore, alternative fields of application are required. In this context, the Deutsche Bundesstiftung Umwelt (DBU) is sponsoring a joint research project which deals with the production and testing of cooling lubricants based on monoesters made from waste edible fats.Methods
In a first step, characteristics and quality of wasteedible fats of different origins were chemically analysed and monitored. The investigations covered the following fat specific parameters: total contamination, sulphate ash, water content, peroxide number, iodine value, kinematical viscosity, neutralisation number (free fatty acids) and fatty acid spectra. In the next step, a process development/optimisation was carried out for the production of methylesters based on the raw material waste fat, leading to the construction of a pilot plant. To investigate the fate of trace pollutants during the production process of waste-fat methylester, samples were systematically contaminated with polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and the elements Al, Cd, Cr, Cu, Ni, P, Pb, Sn, and Zn. These contaminated fat samples were transesterified in laboratory scale. The primary and by-products were analysed subsequently.Results
Valuable hints on the design of the technical process of fatty adid methylester production based on waste edible fats were gained by regarding the fat specific parameters. For example, filtration and dewatering of the waste fats proved necessary. The saturated fatty acids, most wanted for the production of cooling lubricants due to their high oxidation stability, were present in the range of 11,3% to 31,6%. Due to the low content of free fatty acids, a base catalysed process occurred more suitable for the transesterification of the waste edible fats. Trace analytical investigations concerning inorganic and organic pollutants proved a low basic contamination of the waste edible fats. Experiments with systematic contamination of the fats indicated an accumulation of the heavy metals in the glycerol phase during the transesterification process, whereas the organic pollutants were detected in the methylester fraction by amounts of 80% to 95%.Outlook
In a next step, the further processing of the methylesters to monoesters with alcohols of the chain length C2 to C8 will be presented. Associated results of chemical-analytical investigations on the process and the application of the cooling lubricants will also be given. 相似文献22.
Alastair Franke Knud Falk Kevin Hawkshaw Skip Ambrose David L. Anderson Peter J. Bente Travis Booms Kurt K. Burnham Suzanne Carrire Johan Ekenstedt Ivan Fufachev Sergey Ganusevich Kenneth Johansen Jeff A. Johnson Sergey Kharitonov Pertti Koskimies Olga Kulikova Peter Lindberg Berth-Ove Lindstrm William G. Mattox Carol L. McIntyre Svetlana Mechnikova Dave Mossop Sren Mller lafur K. Nielsen Tuomo Ollila Arve stlyngen Ivan Pokrovsky Kim Poole Marco Restani Bryce W. Robinson Robert Rosenfield Aleksandr Sokolov Vasiliy Sokolov Ted Swem Katrin Vorkamp 《Ambio》2020,49(3):784-785
While collating contributions and comments from 36 researchers, the coordinating authors accidentally omitted Dr. Suzanne Carrière from the list of contributing co-authors. Dr. Carrière’s data are described in Tables 1 and 3, Figure 2 and several places in the narrative. The new author list is thus updated in this article. 相似文献
23.
24.
H. Kangro F. L. Boschke G. Feichtinger H. Primas W. Kundt H. Reeh G. Lehner G. v. Minnigerode S. Steeb G. Habermehl R. Hoppe H. Kessler L. Horner M. Kuhnert-Brandstätter L. Jaenicke D. Neubert K. Mothes H. Rembold R. Dietz P. Karlson V. Ziswiler E. P. Martin A. Ruthmann V. Neuhoff R. D. Bauer H. Sioli 《Die Naturwissenschaften》1972,59(3):127-132
25.
26.
Werner Brack Rolf Altenburger Falk Dorusch Andreas Hubert Monika Möder Peter Morgenstern Susanne Moschütz Sibylle Mothes Kristin Schirmer Rainer Wennrich Klaus -Dieter Wenzel Gerrit Schüürmann 《Environmental Sciences Europe》2002,14(4):213-220
In August 2002, highly contaminated areas in the region of Bitterfeld, e.g. the floodplain of the creek Spittelwasser, as well as the adjacent regions of Jeßnitz and Raguhn, were submerged by the river Mulde. An input of mobilized contaminated sediments in residential areas was the matter of concern. The objective of the present study was to estimate the pollutants load on the basis of chemical and biological data and identify the sources of pollutants. Deposited sludge and flood water samples were assessed on the basis of biological and chemical analyses and in comparison with administrative reference values. The pollution of the investigated sites was rather heterogeneous. At several sites, tolerance limits of the German Klärschlammverordnung or the Bundesbodenschutzverordnung were clearly exceeded, e.g. for Pb, As and HCH. Organic extracts exhibited significant effects in several biotests. This may be relevant with respect to direct particle uptake via ingestion or respiration. Pollution patterns for heavy metals as well as for organic pollutants differed significantly from the pattern found in the Spittelwasser flood plain before the inundation, which is in contrast to the initial hypothesis of a possible transport of contaminated Spittelwasser sediments into residential areas. Interestingly, a correlation of chemical load and the overall biological effect could be shown. From the viewpoint of the precautionary principle, the identification of the compounds exerting toxic effects and of the respective pollutant sources would be desirable. 相似文献
27.
28.
K. Mothes 《Die Naturwissenschaften》1960,47(15):337-351
29.
Matthew G. Falk James M. McGree Anthony N. Pettitt 《Environmental and Ecological Statistics》2014,21(4):751-773
Monitoring stream networks through time provides important ecological information. The sampling design problem is to choose locations where measurements are taken so as to maximise information gathered about physicochemical and biological variables on the stream network. This paper uses a pseudo-Bayesian approach, averaging a utility function over a prior distribution, in finding a design which maximizes the average utility. We use models for correlations of observations on the stream network that are based on stream network distances and described by moving average error models. Utility functions used reflect the needs of the experimenter, such as prediction of location values or estimation of parameters. We propose an algorithmic approach to design with the mean utility of a design estimated using Monte Carlo techniques and an exchange algorithm to search for optimal sampling designs. In particular we focus on the problem of finding an optimal design from a set of fixed designs and finding an optimal subset of a given set of sampling locations. As there are many different variables to measure, such as chemical, physical and biological measurements at each location, designs are derived from models based on different types of response variables: continuous, counts and proportions. We apply the methodology to a synthetic example and the Lake Eacham stream network on the Atherton Tablelands in Queensland, Australia. We show that the optimal designs depend very much on the choice of utility function, varying from space filling to clustered designs and mixtures of these, but given the utility function, designs are relatively robust to the type of response variable. 相似文献
30.
The health and safety hazards posed by volcanic eruptions are outlined with special reference to experience gained from the eruptions of Mount St. Helens in 1980. The ability of volcanologists to predict the timing and the impact on local communities of an impending eruption are limited, some recent devastating eruptions having occurred without apparent warning. With the expansion of world populations into hazardous volcanic areas there is a growing need to develop appropriate emergency response measures. This paper describes the main preventive public and occupational health measures that are now a necessary part in dealing with volcanic emergencies. 相似文献