bluuebunny/crossref_metadata_2025 huggingface dataset:
Removal of Indicator Microorganisms in Wastewater Reservoir in Relation to Physico-Chemical Variables
Authors: Fattal B. , Puyesky Y. , Eitan G. , Dor I.
Published: May 2018

Wastewater effluent in Israel was sampled in six reservoirs during different seasons. All the reservoirs were tested for biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), light transmission, temperature, pH, dissolved oxygen (DO), chlorophyll - a, phytoplankton, Zooplankton, as well as microbiological indicators (E.coli. enterococci, heterotrophic bacteria and F+ bacteriophages). The mean reduction of COD, BOD and TSS was 72%, 76% and 45%, respectively and the mean levels at the entrances to the reservoirs were 380 mg/l, 230 mg/l, and 265 mg/l, respectively. The percent reduction of the various microorganisms tested at the entrance to the reservoir and in the reservoir itself ranged between 83.2% and 99.98%. Significant correlation coefficients were found between the concentrations of the various microbiological indicators tested, as well as between the number of indicator microorganisms and pollution parameters (BOD, COD and TSS). A good correlation was found between BOD vs. COD, BOD vs. TSS, and TSS vs. COD. From this preliminary study it may be concluded that a) storage of wastewater in the reservoirs improves the quality of the effluent, and b) changes in physico-chemical parameters and the concentration of enteric microorganisms are significantly correlated.
Zooplankton Community Structure in Hardwater Hypertrophic Lakes of Alberta
Authors: Pinel-Alloul B.
Published: May 2018

Excessive concentrations of phosphorus are a common feature of hardwater eutrophic lakes in western Canada. Preliminary experimental lime treatment showed that this approach had a great potential to reduce phosphorus content and algal biomass. Therefore, two pairs of experimental and reference lakes were selected for a whole lake lime treatment and monitored for a full year prior to manipulation. This study presents the composition and size structure of the Zooplankton community of the lakes before treatment in order to assess the natural summer and inter-lake variations. Before lime treatment, seasonal means of total Zooplankton abundance and biomass ranged from 17 ± 8 to 127 ± 84 ind. L−1 and from 4 ± 2 to 138 ± 236 mg m−3, respectively. The two experimental lakes (Halftnoon and Lofty) were the richest in Zooplankton while the references lakes (Crooked and Jenkins) were the poorest. A total of 30 Zooplankton species (17 rotifers, 2 calanoids, 4 cyclopoids and 7 cladocerans) were recorded as well as 3 chaoborid species. The composition and size structure of Zooplankton varied between lakes and dates. Rotifers accounted for the majority of Zooplankton abundances (59-91%) while Cladocera (78-99%) or Copepoda (74%) in Crooked lake formed most of the Zooplankton biomass. Summer variations of the Zooplankton groups were described along with changes in size spectra. The temporal variation and the inter-lake differences in Zooplankton structure were discussed in relation to trophy, fish and invertebrate predation, and cyanophyte interactions.
Flow Turbulence and Dispersion of Different Matter in the River Mouth
Authors: Shteinman B. , Gutman A.
Published: May 2018

This work presents an investigation of the distribution of turbulent energy in the river mouth and its role in the transport of the matter within the flow. The experimental observations were performed in the River Jordan inflow into the Lake Kinneret. The results were generalized to formulate a conceptual model of the turbulent energy characteristics, specific for the river mouth. This model was extended to include the dispersion coefficients for turbulent flow downstream the river mouth.
Seasonal, Grazing Site and Fish Size Effects on Patterns of Algal Consumption by the Herbivorous Fish, Siganus rivulatus, at Mikhmoret (Mediterranean, Israel)
Authors: Lundberg B. , Lipkin Y.
Published: May 2018

Siqanus rivulatus, a successful herbivorous immigrant fish from the Red Sea, consumes along the Israeli east Mediterranean coast a wide variety of algae. Only four of them composed about a half of the bulk of its food, and only twelve, about 80% of it. Seasonal changes in quantitative representation of different algae in the food followed several patterns. Most algae were taken throughout the year. Proportions in the food of some algae fluctuated only slightly during the year, proportions of others were very great during short periods and much smaller during the rest of the year. Polvsiphonia is an example for the former, Ulva and Spatoglossum, for the latter. Among the latter, Ulva dominates the food contents during the end of winter and spring; Spatoglossum, during the late summer.

As shown previously, s. rivulatus prefers certain algae as food. Nevertheless, food composition in fish captured at inshore sites differed from that of fish captured offshore. This reflects, to a certain extent, the difference in vegetation between these sites, and the fact that the fish tend to graze in a rather limited area at a time.

Small and large fish take different algal food species. Unexpectedly, small fish clearly preferred some large and robust algae, consuming them in much greater proportions than bigger fish. Also unexpectedly, medium size fish showed preferences and avoidances of their own in regard to the consumption of certain algae, and not merely occupied an intermediate position between small and large fish.
The Effects of Exposure to Heavy Metal Ions on Cytochrome b5 and Components of the Mixed-Function Oxidases from the Digestive Gland Microsomes of the Mollusc Monodonta turbinata
Authors: Manelis R. , Hornung H. , Fishelson L. , Yawetz A.
Published: May 2018

LT50 values obtained for Monodontaturbinata exposed to heavy metal ions were as follows: 25.2 days after exposure to final concentration of 1.0ppm Cd+2; 21.2 days for 0.1ppm Hg+2; 25.2 for 0. 5ppm Cr+3 and 16.8 days for 0.5ppm Cr+6, compared to 32.8 days for the control. The final concentrations of metal ions in the mollusc tissue increased by 20 times in the Hg+2, and by 10 times in the Cd+2 treated Monodonta, compared to the untreated control. The normal contents of cytochromes be and P450 in Monodontaturbinata digestive gland microsomes were 195±51 and 58±20 nmol/mg protein, respectively. NADPH-cytochrome c reductase activity was 5.9±3.0 nmol/min/mg protein. Exposure to all heavy metal ions had a destructive effect on the two hemoproteins, especially on cytochrome P450, and a pronounced impact on NADPH-cytochrome c activity which was reduced to about 50% in the treated mollusc. No alarming concentrations of metal ions could be detected in Monodontaturbinata collected from different sites along Israel Mediterranean coast.
Evolutionary Processes and Theory: The Ecological-Genetics Interface
Authors: Nevo Eviatar
Published: May 2018

The evolutionary process is reviewed in terms of the ecological-genetics interface based on genetic diversity in natural populations of plants and animals, using the environmental-genetic correlation methodology at three geographic levels: (1) Local, several species in Israeli microsites; (2) Regional, 21 species across Israel and 2 species in the Near East; and (3) Global, 1111; 184 and 189 species in three studies across the planet. The species analyzed are taxonomically unrelated, and vary in their ecologies, demographies, life histories, and other biological variables. They were mostly tested by horizontal starch gel electrophoresis for allozymic diversity, averaging 25 gene loci, and other genetic polymorphisms. In addition, ten studies involved DNA polymorphisms.

The following results were found at all three geographic levels: (1) The levels of genetic diversity vary nonrandomly and are structured within and among populations, species, and higher taxa; and (2) Genetic diversity is correlated with niche width, and partly predictable, primarily by ecological factors. These results corroborate the adaptive, environmental theory of genetic diversity. They were also verified for several allozyme loci in controlled laboratory experiments in pollution biology. Natural selection in its various forms appears to be a major force maintaining, differentiating and orienting evolutionary change in protein and DNA polymorphisms.
Food and Energy Consumption in Rodents from Different Environments: The Role of Photoperiod in Seasonal Acclimatization
Authors: Haim A. , Rubal A.
Published: May 2018

In several rodent species, changes in photoperiod are important signals for seasonal acclimatization of thermoregulatory mechanisms. Nocturnal rodents inhabiting extremely hot and arid areas like the Arava (Israeli Rift Valley), may be exposed to very low ambient temperatures, which may be far below their lower critical point. In contrast, nocturnal species from the mesic Mediterranean habitats are not exposed to such dramatic seasonal changes.

In the present study, food consumption was measured as apparent digestible dry matter intake (DDMI), while energy was measured as digestible gross energy intake (DGEI), in four rodent species from different habitats. The studied mice were kept under two different photoperiod regimes 16L:8D long photophase, 8L:16D long scotophase at a constant ambient temperature (T =28°C).

In Meriones crassus, which inhabits extremely arid habitats, apparent DDMI and DGEI were significantly higher in long scotophase acclimated individuals when compared with long photophase acclimated. However, in the mesic species Apodemus flavicollis these parameters were similar under acclimation to the two different photoperiod regimes. These results suggest that, in seasonal acclimatization, species from different habitats may have a different response to photoperiodic cues.
Vegetative Propagation of Species of Genus Allium L.
Authors: Kamenetsky Rina
Published: May 2018

The genus Allium L. consists of about 500 species in the Northern hemisphere and includes a large number of useful plants. The highly variable underground organs of Allium species - rhizomes and bulbs - have the function of storing food and moisture in severe environmental conditions. Their other very important function - vegetative reproduction and propagation - increases the chances of survival and supports the genetic stability of natural populations. Among about 40 species studied, 5 types of vegetative reproduction and propagation are distinguishable. The formation of apical buds, daughter bulblets, stolons and apomictic bulblets in the inflorescense have been observed. There is possibly some connection between vegetative propagation, morphological type and life cycle. The process of evolution within the genus and the migration of species to arid conditions lead possibly to the appearance in phylogenesis of prevalence of seminal reproduction over vegetative propagation.
Analysis of Organic Carbon Sediment-Water Exchange in Green Bay, Lake Michigan, USA
Authors: DePinto J. V. , Raghunathan R. , Bierman V. J. , Rodgers P. W. , Young T. C. , Martin S. C.
Published: May 2018

A steady-state sediment carbon mass balance has been performed using data from the Green Bay Mass Balance Study. This analysis aided the calibration of sediment organic carbon resuspension for use in the time-variable PCB mass balance model of the bay. The steady-state analysis indicated that the spatial range of open water resuspension rates was 32 to 195 rara/y, with larger values in shallow, high energy areas of the bay. Under ice, resuspension rates ranged spatially from 15 to 63 mm/y. Gross water column to sediment deposition fluxes and gross resuspension fluxes were by far the largest paniculate carbon fluxes in the systems, with their difference leading to net deposition velocities that ranged spatially from 0.02 to 0.27 m/d during the open water period and from 0.09 to 0.64 m/d under ice.
Forms of Phosphorus in the Sediments of Masan Bay, Korea
Authors: Kim B.-J. , Lee C.-W.
Published: May 2018

The Masan Bay, located in the southeastern part of Korea, is one of the most polluted water bodies in Korea. Sediment-bound P constitutes a vast potential source of nutrients for phytoplankton. Masan Bay was found to be generally polluted by untreated municipal sewage and discharges from a heavy-industry complex. The most abundant fraction of P in the sediments of Masan Bay was residual phosphorus(organic bound P) and the second was NaOH-P(NAI-P) form. Thus in the summer when the water becomes anoxic, an increased flux of P from the sediments occurs.
Sources of Uncertainty in the Application of the Equilibrium Partitioning Approach to Sediment Quality Assessment
Authors: Coates J. A. , Delfino J. J.
Published: May 2018

One widely discussed method to assess biological impact of contaminated sediments is through the application of the equilibrium partitioning model. The partitioning model can be used to develop normalized chemical concentrations that can be correlated to biological effects resulting from sediment contamination. The application of the equilibrium partitioning model requires the measurement or estimation of several model variables. However, the combined uncertainties in the determination of these variables may limit the usefulness of this approach. Uncertainty in estimated pore water effects concentrations and analytical variability of three chemical measurements was investigated using Monte Carlo simulation. Results of Monte Carlo simulations indicated that the levels of analytical uncertainties in the study were acceptable. However, the results also revealed that analytical variability can significantly impair interpretation of the data and should be considered in the choice among different analytical methods. Investigation of duplicate field samples collected in the study indicated an additional source of uncertainty from the occurrence of spatially heterogeneous contaminant distributions.
Functional Approach Leads to Successful ICA across 124 Water and 389 Wastewater Treatment Works
Authors: Parker M. J. , Casey R. J. , Reynolds L. K. , de Vries R. R. , Brueck T. M. , Williams C. N.
Published: May 2018

Thames Water Utilities Limited operates a complex network of 124 water and 389 wastewater treatment works. Regulatory requirements are driving a massive capital programme of more than ₤2 Billion over 5 years to improve performance of these facilities. Improvements are planned, engineered, and operated by a variety of internal and external groups and individuals. Shareholders are demanding profitability and the Director General is pushing for improvements to customer service.

To achieve its objectives, Thames has developed an instrumentation, control and automation (ICA) systems master plan. The plan is based on the utility s water and wastewater functional requirements. The functional approach is applied to the large number of diverse facilities by grouping facilities and processes into classifications. The approach is used throughout the plan. Each process and its associated process control strategy are clearly defined to ensure consistency and the cost-effective implementation of instrumentation and control across Thames.

The functional approach was developed for each process control strategy using a series of structured workshops to achieve consensus and company-wide acceptance. Each department of the utility was involved in the workshops (including engineering, operations, maintenance, management systems, research and development, operational science). Top management sponsored the planning effort and committed to making the plan a reality.
Potential Use of Step Feed Control Using the Biomass in the Settler
Authors: Sorour M. T. , Olsson G. , Somlyody L.
Published: May 2018

In spite of the widespread availability of step feed configurations in activated sludge systems, little use has been made of their control potential. The main aim of this study is to provide a better understanding of applying step feed control considering the role of biomass activity in the settler. The control strategy was evaluated by simulating the dynamics of an activated sludge system. The model contains both biomass activity in the settler and step feed capabilities. The model and the strategy then have been evaluated against pilot scale and full scale experimental data.
Development of New Polymer Dosage Control Method for Sludge Dewatering Process
Authors: Igarashi Chiaki , Tanaka Kazunari , Kitamura Teruaki , Fujita Kazuo , Arai Kazuaki , Kameyama Kenichi
Published: May 2018

In a sludge dewatering process using polymer, controlling the polymer dosage is an important factor for upgrading performance and achieving a saving on costs. A new automatic polymer dosage control method has been developed by the authors, which features the use of a streaming current detector or a colloid titrator. These detectors detect the colloidal charge of the filtrate from sludge. The said method was used with actual dehydrators and the following advantages were confirmed.(1) The said method is applicable for various types of dehydrators.(2) The said method is effective even when there are changes in sludge characteristics.(3) The said method is more economical than a conventional solids proportional control method in that less polymer is used.
Control Design for Nonlinear Wastewater Treatment Processes
Authors: Dochain D. , Perrier M.
Published: May 2018

This paper deals with the design of adaptive nonlinear control algorithms of biological wastewater treatment processes. The control design is based on the dynamical mass balance equations of the process and includes the on-line estimation of uncertain parameters (specific growth rates and yield coefficients). The procedure is illustrated by two examples (activated sludge process, anaerobic digestion).
Statistical Analysis of Operation Data and Automatic Control on Fluidized Bed Incineration Plant with Dryer
Authors: Minami Shigeki , Nagasawa Hidekazu , Saito Yoshinori , Yamagishi Motoharu , Hiraoka Masakatsu , Takeda Nobuo , Okajima Shigenobu
Published: May 2018

Continuous operation data were obtained on a fluidized bed incineration plant with dryers, and two autoregressive models were then prepared through statistical analysis of the data. Based on the results, an automatic plant control system using fuzzy theory was designed. An incinerator system of this type is characterized by energy efficiency, for which optimum and stable moisture control of the dried sludge is important. The large difference in time constants between incinerator and dryers makes energy saving difficult. Based on these analyses and design, control operations at a commercial plant with a capacity of 150 wet-tons/day were studied. It was confirmed that reduction of auxiliary fuel consumption and reduction of CO and NOx in the exhaust gas were optimized, while the moisture content of dried sludge and the furnace temperature were kept stable.
Control of Activated Sludge Plants Based on Measurement of Respiration Rates
Authors: Klapwijk Abraham , Spanjers Henri , Temmink Hardy
Published: May 2018

An integral control strategy for activated sludge plants presented in this paper consists of three low-level control tasks. The first is the actual respiration rate control by manipulating the influent flow rate, whereby the aerators are at a fixed position for each setpoint. The second task is the maximum respiration rate control by manipulating the waste activated sludge flow rate. The third task of the integral control strategy is the instantaneous respiration rate monitoring, which informs the operator about the performance of the process.
Simultaneous Biokinetic Characterization of Heterotrophic and Nitrifying Populations of Activated Sludge with an On-Line Respirographic Biosensor
Authors: Vanrolleghem P. A. , Verstraete W.
Published: May 2018

The more stringent requirements imposed on wastewater treatment systems result in an increasing demand for on-line monitoring equipment for these processes. The paper presents the modification of a fully operational respirographic biosensor to allow simultaneous and on-line biokinetic characterization of both BOD-removal and nitrification capacities of activated sludge.

For this characterization, advantage is taken of the calibration measurements that are performed regularly (every 2-3 h) during normal operation of this biosensor. The injection of a well chosen calibration mixture of readily biodegradable BOD and ammonia to a small activated sludge filled bioreactor results in oxygen uptake rate profiles that are interpreted in the framework of a mathematical model that describes the combined oxygen consumption for BOD removal and nitrification. Model identification gives rise to biokinetic parameters (max. conversion rates and affinity constants) that are indicative of the different metabolic capacities of the activated sludge. It is shown that this information can be used to assess the effect of injected wastewater samples on the sludge condition, e.g. adaptation or inhibition, and allows one to follow the change in relative abundance of heterotrophic and nitrifying populations.

Special attention is paid to the proper composition of the calibration solution. Especially the ratio between NOD and BOD is found to be critical. With the aid of simulation, sub-optimal experimental designs are proposed that allow reliable estimation of the biokinetic parameters. Finally, validation of the proposed design is given with experimental data.
Cross Comparison of Techniques for the Monitoring of Total Organic Carbon (TOC) in Water Sources and Supplies
Authors: MacCraith B. , Grattan K. T V. , Connolly D. , Briggs R. , Boyle W. J. O. , Avis M.
Published: May 2018

A comparison of UV (254nm) absorption spectrometry, optical fluorescence (excitation at 340nm, emission measurement at 420nm) and established chemical methods for estimating Total Organic Carbon (TOC) in water samples obtained from a variety of sources has been made. In addition, a proprietary UV in-line absorption monitor commonly used in industry is assessed relative to these measurements. The work has shown a strong correlation between Total Organic Carbon (TOC) measurements and both UV absorption and fluorescence measurements. These measurements indicate the feasibility of both approaches in the design of new field based instruments for TOC determination using optoelectronic devices.
Comparison of Gold and Platinum Electrode Responses in Activated Sludge
Authors: Heduit A. , Martin B. , Duchamp I. , Thevenot D. R.
Published: May 2018

Gold and platinum were compared to ascertain how they expressed a stabilized potential in activated sludge. The comparison was based on electrochemical determination of the electron transfer rate (i.e. equilibrium exchange current density) and recording of potentials against time.

When both metals are treated in the same way, platinum gives equilibrium exchange current densities approx. 10 times higher than gold, both in aerated activated sludge and in treated water. For platinum, the equilibrium exchange current densities range from 0.1 to 0.25 µA/cm2 immediately after polishing and decrease during prolonged contact with activated sludge subjected to alternating aeration/anoxia sequences.

The lower kinetics of electron transfer on gold go together with significant differences in response:- In an aerobic medium a gold electrode potential is lower than that of a platinum electrode. In a strongly anaerobic medium, the reverse is true. Consequently, the amplitude of the potential variation between aerobic and anaerobic media is smaller for gold than for platinum. Under our experimental conditions this amplitude was approx 350 mV for gold and 850 mV for platinum.- The slopes of the linear relationships between potential and pH or potential and the logarithm of the dissolved oxygen concentration are two or three times greater for platinum than for gold.

Although the values obtained with platinum electrodes cannot represent a veritable equilibrium state, the platinum electrode zero-current potential would seem to be far more sensitive to variations in the medium than that of the gold electrode; it is, therefore, more suitable for use in activated sludge.
Inventory and Assessment of Automatic Nitrate Analyzers for Urban Sewage Works
Authors: Wacheux Hervé , Da Silva Sylvain , Lesavre Jacques
Published: May 2018

An inventory of the European market showed that 12 automatic nitrate analyzers were available using measuring techniques based on ion specific electrodes, colorimetry and UV absorption.

Among these analyzers the following six - Data Link, Dr Lange, M.E, Phox, Polymetron, Process Styrning - were put through two series of tests:- metrological characteristics of the instruments,- behaviour in waste water and comparison with analyses of samples in laboratory.

The metrological quality of all the analyzers is sufficient, but all the ion specific electrode analyzers showed contamination and rapid drift when used in waste water.

The others show greater resistance. UV absorption systems are simpler and quicker to use. They are also less demanding with regard to sample conditioning than colorimetric apparatus.
A NEW STREETS CAPE FOR STORMWATERMANAGEMENT IN MEDITERRANEAN -CLIMATE CITIES: THE CONCEPT EXPLORED
Authors: Argue John R.
Published: May 2018

The water resources crisis facing countries of the Mediterranean Basin is reflected, in diminished form, in the semi-arid, “Mediterranean-climate” zone of Australia. Some creative solutions involving the collection, treatment, storage, retrieval and use of storm runoff to replace the component of mainssupplied water presently used for “second quality” purposes, are emerging in Adelaide, capital city of South Australia. The paper describes one initiative being taken to achieve source control of stormwater – quantity and quality – in mixed-density residential streets. The resulting streetscape is suitable for use in both “greenfields” and re-development projects. The paper explores the hydrological/hydraulic performance of the system and shows that it satisfies all theoretical- requirements for safety in the full range of flooding up to and including the “once in 100-years” event. The new streetscape holds the following advantages over conventional streetscapes : reduced peak outflows, greatly improved effluent water quality, aids “greening” of the landscape, potential for aquifer recharge where appropriate, aquiferretrieved groundwater can replace mains water used for irrigation, “nuisance” flows are fully contained (no surface appearance), major flows only occupy the swale, street residences are less flood prone and the streetscape fits more harmoniously into undulating terrain.
GROSS SOLIDS IN SEWER SYSTEMS: TEMPORAL AND CATCHMENT BASED RELATIONSHIPS
Authors: Jefferies C. , Ashley R. M.
Published: May 2018

The behaviour of gross and visible solids was studied at two combined sewer overflow sites using the WRc Gross Solids Sampler. At one of the sites the daily variation of gross solids during dry weather was determined. There was found to be close correspondence between the variations of gross and suspended solids in the sewage. A relationship was developed between the load of gross solids and that of suspended solids at the observation point in dry weather. This relationship is presented for use with other predictive methods.

A chart is presented which differentiates with a high degree of reliability the gross solids production of two different types of catchments, one being a collector sewer catchment, the other being a trunk. The rate of gross solids production has been found to be a critical factor in differentiating between the catchments. A consistent and further differentiation in the accumulation of gross solids is presented on the basis of antecedent dry period, greater than 24h allowing considerably greater accumulations than shorter dry periods.
A ROBUST INTEGRATED COMPUTER-AIDED DESIGN PACKAGE FOR URBAN DRAINAGE NETWORKS
Authors: Chau K. W. , Ng S. L.
Published: May 2018

This paper presents the development and verification of a computer aided design and drafting package for medium sized municipal storm water drainage systems (DRAINAGE). The numerical model, which is designed for use on microcomputers, is written in PASCAL Language and is compiled by PC software TURBO PASCAL version 6.0. The computer package for flow prediction and drainage design applies the Colebrook White Equation and the Rational Method to route pipe flows through tree-type drainage networks, automatically adjusting drainage pipe diameters to fulfil flow requirements and backwater effects. The progrmn outputs are written as DXF files which can be read and displayed readily as drawings of drainage layout plml ,md longitudinal profiles in an AutoCAD environment. DRAINAGE replaces the timeconsuming conventional method for designing stormwater drainage networks. Although the prognun is tailored for application and use in Hong Kong, it can be easily adapted to other situations.
CONSEQUENCES OF THE BEHAVIOUR OF ACTIVATED SLUDGE PLANTS WITH COMBINED SEWAGE INFLOWS
Authors: Londong Jörg
Published: May 2018

The paper deals with the dynamic behaviour of activated sludge plants resulting from combined sewage inflows. Implications for the planning and operation of activated sludge plants are inferred from this behaviour. On the basis of a measured rain event dynamic simulation is used as a tool to investigate the influences of combined sewage inflows. Following an increase in the water inflow rate due to rain, a significant increase in concentration of nitrogen is observable at the outflow of the activated sludge tank The reason for this is the total Kjeldahl nitrogen influent load peak generated by the combined sewage inflow, together with displacement of biomass to the secondary sedimentation tank. Since the effluent concentration peaks are caused by inflow load peaks, measures must be taken to buffer these load peaks in the inflow zone. Best results can be achieved with inflow storage. Given a sufficiently large storage tank and optimum load management, a relatively low ammonium effluent value could be maintained even at high inflow rates. Optimum inflow control is feasible if both the water volume and the nitrogen concentration can be measured at the inflow and can be influenced by means of storage tanks. Dynamic simulation continues to be useful during operation, and can support tank control.
SIMULATION OF NITRIFICATION AND DENITRIFICATION PROCESSES IN A TIDAL RIVER
Authors: Kusuda Tetsuya , Futawatari Tohru , Oishi Kyoko
Published: May 2018

Nitrification and denitrification processes in a well mixed tidal river in Japan are modeled, based on results of long term field observation on water quality and sediments in the river. Laboratory test results and values in references are used for the determination of parameters and coefficients in the model. In modeling of the processes, sediments, suspended solids, and overlying water are taken as elements and in computation a Lagrangian reference frame in terms of accumulated water volume is employed for reduction in numerical dispersion. Simulation results on ammonium and nitrate nitrogen, showing good agreement with long term field observation results, qualitatively explain well the processes in the river. The results indicate some countermeasures to reduce nitrate more such as the increase in the area of sediment surface. The simulation model is available for the estimation of water quality in well mixed tidal rivers and applicable for water quality control.
PHOSPHORUS GENERAL LOAD ON WATER ECOSYSTEMS: ASSESSMENT BY SIMULATION PHOSPHORUS MODEL
Authors: Leonov A. Y.
Published: May 2018

The basic objective of the research was to generalize the results obtained by the simulation model of the phosphorus system in studying eutrophication problems for different water bodies, The phosphorus model had been originally applied to the Lake Balaton (Hungary), and then to other water bodies – Ivan'kovskoe Reservoir, Lake Kubenskoe, Lake Uvildy (Russia), Lake Kuortaneenjarvi, Lake Tuusulanjarvi, Lake Kotojarvi (Finland), South-East part of Finnish Gulf. An analysis of the combined simulation data for water bodies studied by the model allows us to estimate features of phosphorus changeability and its general load taking into account an external phosphorus input plus an internal phosphorus cycling into the water ecosystem.
MODELING OXIDATION DITCHES USING THE IA WPRC ACTIVATED SLUDGE MODEL WITH HYDRODYNAMIC EFFECTS
Authors: Stamou Anastasios I.
Published: May 2018

A mathematical model is presented to predict the concentrations of the active heterotrophic biomass, the readily biodegradable substrate (soluble COD) and the dissolved oxygen (DO) in a completely aerobic oxidation ditch. The model involves the one-dimensional convection-dispersion equations for biomass, COD and DO. Hydrodynamic effects are represented in the model by the values of the average flow velocity and the dispersion coefficient. Biological processes are described in the model according to the IA WPRC activated sludge model, using typical values for the model parameters at 10°C. The equations are solved with the finite volume method. The application of the model leads to the following conclusions: (i) Steady state biomass concentrations are almost constant throughout the ditch. (ii) Steady state COD concentrations in the ditch are very low, and COD removal efficiency is practically independent of the values of the flow velocity and the dispersion coefficient. The distribution of the COD concentration in the ditch is less uniform, when small values of the dispersion coefficient are used. (iii) The distribution of the DO concentration in the ditch is very sensitive to the values of the flow velocity, the dispersion coefficient and to the capacity of the rotors. DO concentrations increase when the dispersion coefficient decreases or the flow velocity increases. (v) Daily sludge production, oxygen requirements and sludge age are calculated equal to 0.44 g (g COD removed)‒1, 0.56 g (g incoming COD)‒1 and 6.3 days, respectively.
A MATHEMATICAL MODEL FOR ENHANCED BIOLOGICAL PHOSPHORUS REMOVAL
Authors: Ante Angela , Besche Hans Ulrich , Voss Harald
Published: May 2018

The incorporation of enhanced biological phosphorus elimination in the single sludge process is a contemporary challenge in the design of biological wastewater treatment plants. The simultaneous biological removal of nitrogen and phosphorus is a process of considerable technical and biological complexity owing to the mixed substrates and the diversity of microorganism populations. In addition, an interaction takes place between the phosphorus-accumulating organisms and the nitrogen-eliminating organisms owing to the physiological demands. When designing wastewater treatment plant, it is necessary to establish anaerobic zones for producing the short fatty acids necessary for phosphorus removal, an xic zones for denitrification, and aerated zones for nitrification and phosphorus removal.

We have developed a mathematical model based on IA WPRC-model No I for this process scenario. In addition to the degradation kinetics of carbonaceous components and nitrogen, the model describes the microkinetics of enhanced biological phosphorus elimination. The assumptions of the model are discussed in relation to the recent literature. The range of values found in the literature and the used default values of the model parameters are listed. The simulation program is presented, and first results of simulation are shown.
CONTINUOUS AND EARLY DETECTION OF TOXICITY IN INDUSTRIAL WASTEWATER USING AN ON-LINE RESPIRATION METER
Authors: Kim Chang-Won , Kim Byung-Goon , Lee Tae-Ho , Park Tae-Joo
Published: May 2018

An on-line toxic detection system is introduced for early and continuous observation of toxicity in an industrial wastewater treatment plant. The system consists of a contact chamber and an on-line respiration meter. If a raw wastewater sample is taken at the head of the wastewater treatment plant, one can detect toxicity of the wastewater before it reaches the aeration tank. For proper usage of this system a maximum respiration rate should be measured in the contact chamber. To apply this system on the petrochemical wastewater the Qe/Qs, ratio should be maintained higher than 0.6 among other operating conditions required When this system was tested under high and low pH, Co2+ inhibition, and recovered catalyst wastes addition, the system responded very sensitively.
The Development of the Macrozoobenthos in the River Rhine in Germany during the 20th Century
Authors: Tittizer Thomas , Schöll Franz , Dommermuth Maria
Published: May 2018

The development of the zoobenthic biocoenosis in the River Rhine in Germany during the 20th century has been documented in literature and by own investigations. The diversity of species and the structure of zoocoenosis are the elements of comparison. They show a drastic and continuing impoverishment in the benthic macroinvertebrate fauna throughout the 1950s, 1960s, and in the early 1970s. Since the raid-seventies a steady recovery of the communities has been observed. Causal dependencies between the development of the zoocoenosis and environmental factors like water pollution, river training, navigation and invasion of alien species (Neozoa) are discussed. Actions for improving the ecological situation are proposed.
Load Trends of Selected Chemical Parameters of Water Quality and of Trace Substances in the River Rhine between 1955 and 1988
Authors: Hellmann Hubert
Published: May 2018

The period between 1955 and 1988 was the time of reconstruction in the destroyed Federal Republic of Germany, marked by booming industrial development and - with some delay -by the rise and spread of ecological awareness and the idea of water conservation. This is the background against which the analysis of water quality and of pollution load trends should be seen.

The study of a long-term load trend presupposes the following requirements:–sufficiently large number of measured data;–reliable, reproducible analytical methods which produce comparable results over long time series; and–hydrological interpretation and evaluation of results.

The continuous efforts to improve analytical methods and the elimination of distorting substances and matrix effects led to the situation that long time series of data are not directly comparable. In some cases, summative analyses (aggregate parameters) have been replaced by newly developed substance-specific methods so that the continuity of records has been broken.

Furthermore, there is a general underestimation of the necessity to consider and evaluate analytical data in a space-time continuum.

However, on the whole, we are able to give a satisfying interpretation of trends for the classical parameters. In the case of the trace substances detected by modem methods, this is possible only for the past two decades and with some reservations.
TREATABILITY OF 2,4-D PRODUCTION WASTEWATERS
Authors: Tünay O. , Erden S. , Orhon D. , Kabdasli I.
Published: May 2018

This study evaluates the characterization and treatability of 2,4-D production wastewaters. Wastewaters contain 20000-40000 mg/l COD, 17000-30000 mg/l chloride and pH is around 1.0. Chemical oxidation with hydrogen peroxide provided almost complete COD removal. The optimum conditions are 3:1 H2O2/COD oxidant dosage, 3000 mg/l Fe3+ as catalyst and pH 3. Partial oxidation at 0.5:1 H2O2//COD ratio is also effective providing 67% COD removal. A batch activated sludge system is used for biological treatability. Dilution is needed to maintain a tolerable chloride concentration which increases through COD removal. pH also increased during COD removal. 85% COD removal is obtained for the 50% dilution at an organic loading of 0.3 day‒1 on a COD basis. Completely and partially oxidized wastewaters are also treated in the activated sludge down to 30 mg/l BOD5.
Trend Analysis of Heavy Metal Concentration of the Suspended Matter in the River Danube
Authors: Oertel N.
Published: May 2018

The systematic investigation of heavy metal content in suspended matter is suitable for distinguishing point and non-point sources and for establishing trends of pollution if the dataset is analysed separately, considering the low and high average water discharge periods.

At the examined reach of the Danube (at 1669 km) Ag,Cd,Cr,Cu,Ni,Pb and Zn can be considered as constant and/or intermittent pollutants derived from a few point sources of pollution situated upstream. In the late eighties Ag,Cd,Cu,Pb and Zn concentration of suspended matter had been increased mainly in the range of low average water discharge (LWD), which provides evidence for an increase in emission.
ANAEROBIC TREATMENT OF DISTILLERY SLOPS IN THE CIRCUMSTANCES OF CENTRAL EUROPE
Authors: Jenícek Pavel , Zábranská Jana , Dohányos Michal
Published: May 2018

Anaerobic treatment of many kinds of slops is one of the most progressive ways for the reuse of this material. The special feature of Central Europe is that the largest proportion of ethanol is produced by fermentation, and the raw material in big distilleries is only sugar beet molasses. The consequence of this is a large production of slops in small regions, and as far as the quality of slops is concerned, a relatively high content of inert and nonbiodegradable organic compounds in comparison with other more valuable raw materials, such as grapes, fruits, cereals, potatoes, etc. A two-year operation of the pilot scale UASB reactor bas shown that molasses slops are a suitable material for anaerobic treatment The slops were diluted by other wastewaters from the distillery to a concentration of about 25 g.l‒1 COD and then treated in the pilot reactor at 32°C with the following average results: COD removal efficiency 78.8 %; volumetric loading rate 7.1 kg.m-3.d‒1; volumetric gas production 2.6 m3.m‒3.d‒1; specific gas production 0.47 m3.kg‒1. The results achieved confi11II that molasses slops are a source of energy. For example, Czech distilleries could potentially produce 12-17 million m3 of the valuable gas fuel per annum.
Preventing Accidental Spills: Risk Analysis and the Discharge Permitting Process
Authors: van Baardwijk Frans A. N.
Published: May 2018

The contribution of accidental discharges to the total emission of contaminating substances in surface waters is relatively increasing, as regular discharges are reduced.

In The Netherlands a program has been started to develop a quantitative risk analysis method to be used within the discharge permitting process. The methodology takes into account the type of activities and related accident scenarios in terms of failure frequencies and source sizes, correction factors according to specific circumstances, as well as the nature of the receiving system (types of surface waters, but also public sewage water treatment plants). The methodology will provide an indication of the risk reduction needed in terms of reducing the frequency and/or the volume of possible spills.

The method itself, the use of it within the legal framework and the relation with the EC-Directives are discussed.
Countering Acute Pollution Events: Procedures Currently being Adopted in the United Kingdom
Authors: Cole J. A. , Norton R. L. , Montgomery H. A. C.
Published: May 2018

Twenty English and Welsh water companies and the water services in Northern Ireland have collectively funded the production of a Manual on Pollution Risk Management. The Manual, which is still in draft, is intended to create a practical and systematic procedure for identifying potential and actual risks of pollution, for cutting down on those risks and for dealing with such incidents as do occur. The risks are considered of how pollution could affect surface or groundwater sources, or both of these, with a view to achieving catchment-wide awareness, supported by monitoring as necessary.

The poster sets out the structure of the Pollution Risk Management Manual, covering:pollution incident categories and the frequency of consequent problems affecting public water suppliesa survey of European waterworks practice in monitoring and responding to acute pollutant eventscatchment audits to identify and curtail existing hazardspriority pollutants, their toxicities and persistence in the environment (WRc Toxicology Advisory Service)pollutant transport, in surface and groundwatersaction plans when faced with pollution incidentsclean-up procedures following pollution incidents.
Biological Early Warning Systems for Surface Water and Industrial Effluents
Authors: Balk F. , Okkerman P. C. , van Helmond C. A. M. , Noppert F. , van der Putte I.
Published: May 2018

Within the framework of the International Rhine Action Programme and the EC ACE-Programme in the field of the environment (regulation EC.224/87) the sensitivity and reliability of biological early warning systems are being tested. The effectiveness of these systems for continuous water quality monitoring is being assessed, using surface water and industrial effluents.

The systems tested are a fish and a waterflea early warning system. From the results it is concluded that both types of biological early warning systems in combination with physico-chemical monitoring increase the effectiveness of monitoring pollution levels in surface water. Fish early warning systems can be important tools in reducing water pollution by industries.
Biological and Ecotoxicological Monitoring of the Rivers Rhine and Meuse by the Drinking Water Industry
Authors: Ketelaars H. A. M. , Volz J. , Jülicn W. F. B.
Published: May 2018

The biological and ecotoxicological monitoring of the Rivers Rhine and Meuse is of great importance to the drinking water companies that depend on these rivers. An overview is given of the monitoring programme of the last two decades.
Outline of the Ecological Master Plan for the Rhine
Authors: Schulte-Wülwer-Leidig A.
Published: May 2018

The “Ecological Master Plan for the Rhine (Salmon 2000)” was elaborated within the framework of the “Rhine” Action Programme (RAP). It focuses on two points.Restoration of the main stream as the backbone of the ecosystem Migratory fish can only return to the Rhine when certain conditions are given. Improvement measures must be realized. For the support and realization of the project “Salmon 2000” two applications for subsidies were approved by the European Community. The first project concerns various habitat improvements, re-establishing, re-stocking and success control measures in several Rhine tributaries. The second project concerns the methods of improvements at barrages which are currently considerable obstacles to migration. At the barrages of Iffezheim and Gambsheim/Upper Rhine, new fish ladders must be built. The Master Plan will only prove successful if the re-establishing and restocking of habitats is being carried out simultaneously with measures aiming at reestablishing the surmountability of barrage weirs.Preservation, protection and improvement of ecologically important reaches. The plan demands an extension of the alluvial areas. Complete ecological interaction between these areas and the river must be allowed. A group is working on a specific ecological network with the most important alluvial areas along the Rhine. These areas shall serve as “stepping stones” for the whole Rhine ecosystem.

This plan may be considered as an exemplary conception of international waterways protection. Its significance includes amongst other things the applicability to other similar river systems.