Qualitätsanforderungen an Oberflächengewässer: Zielvorgaben,Qualitätsziele und chemische Gewässergüteklassifizierung

Quality Requirements for Fresh Waters: Water Quality Targets, Water Quality Objectives, and Chemical Water Quality Classification In the Federal Republic of Germany, water quality requirements for the protection of inland surface waters against hazardous substances are formulated on the basis of a quality targets derivation concept developed jointly by the Federal Government and the Federal States. The quality requirements were termed “water quality targets” in order to make it clear that the values derived are orientational values rather than legally binding limit values. The international comparison of quality requirements for surface waters shows that, on the whole, the national quality targets ensure a high level of protection. According to present scientific knowledge, impairments of uses, such as supply of drinking water, or risks to aquatic communities need not to be expected if the quality targets are complied with. A comparison of water quality data with the water quality targets makes it possible, on the one hand, to identify those substances whose inputs must be further reduced; on the other hand, it also shows that, for a number of substances, there is no need at present for concern over their adversely water quality. A further differentiation of the aquatic hazard potential of pollutants allows a water quality classification system to be developed on the basis of the quality targets derivation concept. The basic elements of this water quality classification system are presented, and its application is explained by way of examples.     

Oberflächenaktivität und bakterizide Wirksamkeit quaternärer Aminooligomere

We synthesized series of polyfunctional aminooligomers by means of condensation from polychlorparaffine with ethylenediamine. After modifying them with dimethylsulphate watersoluble oligomers of (quaternary) polyamines are obtained, which can be successfully used as biocides for treating circulating cooling-waters from different refinery plants. The products have low foaming and formed foam is unsteady. The bactericide properties of the successful samples are good. For the interval time for two to twenty hours of treatment at static conditions the microbe number value decreases by more than 99.99% at a 50 mg/dm³ dose of a biological active substance. At dosing it up to seventy-two hours the biomass is finely dispersed and does not precipitate on the walls of the chemical set-equipment.     

Einsatz von Pflanzenkläranlagen zur Behandlung von schadstoffbelastetem Oberflächenabfluß städtischer Straßen

A combination of retention pond and reed bed was tested for its effectiveness in reducing non-point source runoff pollution from an urban area. This paper presents data on the development of reed plants (Phragmites australis Cav. Trin.), on the effectiveness of runoff purification and on the accumulation of contaminants in the pond sediment and the reed bed for the years 1993–1995. P. australis was well established and grew according to normal development. The measured length and biomass values of P. australis were larger on sand than on gravel and coarse materials. Toxic levels of heavy metals in the plants were not reached. Harvested plants can be composted. The purification system is effective within the following ranges: The rate of retention of suspended solids and heavy metals varies between 16% and 91%. For chemical oxygen demand the average values is 25%. Poor retention rates usually occur along with very low input concentrations. Generally retention within the reed bed is higher than in the pond. Between 1993 and 1995 the concentration of contaminants within the organic layer of the reed bed increased by 50% for lead and by 90% for poly aromatic hydrocarbons. Until 1994 the concentrations of mineral oil hydrocarbons also increased by 60%. Between 1994 and 1995 however the concentration of mineral oil hydrocarbons in the reed bed decreased rapidly by more than 50%: Mineral oil hydrocarbons underlie biological degradation within the reed bed. In the pond sediment a significant accumulation of heavy metals, poly aromatic hydrocarbons and mineral oil hydrocarbons has also been found. The concentrations of these contaminants are still far from inhibiting the function of the system.     

Gesetzmäßigkeiten des Sauerstoffaustausches zwischen Gewässer und Atmosphäre im Flußmündungsgebiet

Meteorological conditions, biochemical processes in water bodies and anthropogenic pressure of a region are the main factors to determine the atmosphere water-body gas exchange. Research on oxygen outflows in the Dnjepr estuary region has shown that though gas exchange with atmosphere permanently exists its intensity varies throughout a day, vegetation period, year. The process of evasion is the most active in the flood plain pools of the river. Oxygen exchange between the atmosphere and a river is to be determined with physical characteristics of water outflow and with the anthropogenic influence. Oxygen absorption from the atmosphere is dominating for the liman water area in spite of differences between its parts. The obtained results have shown that gas exchange between river estuary pools and the atmosphere is of great importance for the oxygen balance of these pools.     

Schwermetallbestimmung in Klärwerksschlämmen mittels Röntgenfluoreszenzanalyse

The X-ray fluorescence analysis is an important means for the determination of the heavy metal concentrations in sewage sludges and for the evaluation of their usability in agriculture. Analysis devices from the GDR were used for that. For the investigations there was used as the zero sample a sludge which was not loaded with heavy metals, homogeneous and constantly dried at 105 °C. The drying bed sludge samples were treated with different heavy metal solutions with different concentrations. Preparation of samples, measuring conditions and general spectra are described. The measuring results of tests up to 100 g heavy metal in 1 kg dry substance are critically evaluated. The analysis of a sewer sludge sample takes only about ten minutes. There are determined: Cr, Ni, Cu, Zn, Mo, Cd, Hg and Pb.     

Chlorphenole und Nonylphenole in Klärschlämmen. Teil I: Vorkommen in Klärschlämmen westdeutscher Kläranlagen aus den Jahren 1987 bis 1989

Chlorophenols and Nonylphenols in Sewage Sludges. Part I: Occurence in Sewage Sludges of Western German Treatment Plants from 1987 to 1989 Sewage sludges originating from all western German states from 1987 till 1989 have been analyzed for two groups of organic pollutants, which are not specified in the German sewage sludge regulations (Klärschlammverordnung) from 1992: the isomeric 4-nonylphenols and the chlorophenols. The applied analytical methods are presented, as well as the analytical results. In almost all 149 analyzed samples nonylphenols could be found, at an average of 128.2 mg/kg dry matter. In the case of chlorophenols, pentachlorophenol was the most pronounced in respect to amount and to frequency of positive results: i.e. in 85 samples investigated, the mean value was 59.5 μg/kg. Results are reported in percentils. The data correspond to sewage sludges from the past and will be used as a guideline in evaluating all following studies of sludges. Investigations will be continued.     

Elektrochemische Einschätzung des Oberflächenzustandes von Wasserreinigungskohlen

Electrochemical Characterization of the Surface of Activated Carbon Used in Water Treatment Plants. We tried to measure electrochemically those properties of activated carbons which are important for using them for water purification. A success was achieved with the electrochemical immersion potential U_i which is found to be a function of concentration of functional surface groups on the carbon surface. However, the expected direct proportionality for inert surfaces between BET surface area and amount of charge measured in recharge processes has not been observed.     

Immersionskalorimetrische Einschätzung der Adsorptionsfähigkeit von Aktivkohlen gegenüber organischen Stoffen aus wäßrigen Lösungen

In comparison with the conventional methods for testing the adsorptive capacity of active charcoals, the author presents a new technique. The measuring possibilities of the immersion calorimetry are used. This measuring technique is based on the determination of the interaction of active charcoal with liquid adsorptives. The immersion heat referred to one mol adsorptive is used as the measure. Due to simplifying assumptions and a micropore volume of active charcoal measured with water vapour, immersion-calorimetrically relative equilibrium constants can be determined. By the example of phenol and indol, the adsorptive capacity of several domestic and foreign samples of active charcoal is assessed on the basis of the difference of the immersion heats in benzene and water.     

Biochemisch-makrophytische Methode der Nährstoffeliminierung aus Oberflächenwässern auf der Grundlage der Infiltration

Die natürlichen Fähigkeiten und Eigenschaften von Makrophytenbeständen, insbesondere bestimmter Pflanzengruppen der überschwemmungswiesen, für Nährstoffeliminierung und Grundwasseranreicherung werden der biochemisch-makrophytischen Methode zugrunde gelegt. Am Beispiel von Kleinstsickerbecken wird die Methode zur Nährstoffelimination aus Oberflächenwässern beschrieben. Prinzip, Durchführung und Auswertung der Methode werden am Beispiel verschiedener Makrophytenarten für verschiedene hydrochemische Parameter anhand von Grenzwerten, Eliminierungs- und Infiltrationsraten dargestellt. Geeignete Einsatzmöglichkeiten der Methode für wasserwirtschaftliche und landeskulturelle Zwecke werden besprochen.