bluuebunny/crossref_metadata_2025_split huggingface dataset:
Receiving Water Protection During Wet Weather
Authors: Krejci Vladimir , Schilling Wolfgang , Gammeter Sonja 
Published: May 2018

It is proposed that in the future only site-specific and problem-related measures should be applied to solve the combined sewer overflow problem. Based on experience in Switzerland a procedure is developed to plan technically and ecologically optimised measures to protect urban receiving waters during wet weather. This procedure is based on results of a field study (the Fehraltorf/Switzerland case) carried out by a multidisciplinary research team. The most important stages of the procedure can be described bythe definition of site-specific ecological objectives,the determination of a few key variables that have significant influence on the ecological state of the receiving water and that can be modified with some of the site-specific measures below,measurement, observation, and calculation of these variables,choice of site-specific measures against wet weather pollution problems (in catchment, sewer system, and receiving water), andrecommendation of measures and their priorities, based on predicted cost and effectiveness with respect to the variables above.
The results of the case study demonstrate the necessity of the multidisciplinary approach that treats the urban catchment, the urban drainage system, and the receiving water as one single system. Since urbanised areas continue to grow and since the reconstruction of old depreciated sewer systems is a major technical and economical challenge, the proposed modification of the planning concept may lead towards improved drainage systems, requiring appropriate investment, and causing less serious damage to the environment.
Nitrogen, Phosphorus and Metal Loads from Swedish Pulp and Paper Industry on the Gulf of Bothnia – Quantities and Shares of Total Loads
Authors: Enell M. , Haglind I. 
Published: May 2018

The drainage area of the Gulf of Bothnia is 481,000 km2, of which about 2/3 is located in Sweden and 1/3 in Finland. About half of the drainage area is forest and only 4% is agricultural land.
The total annual load of nitrogen on the Gulf of Bothnia is 175,000 tonnes, of which 55,000 tonnes comes from Sweden, 39,000 tonnes from Finland, 77,000 tonnes with atmospheric deposition on the sea surface, and 4,000 tonnes from nitrogen fixation. The Swedish pulp and paper industry discharged 2,300 tonnes of nitrogen into the Gulf of Bothnia in 1991, corresponding to 1% of the total nitrogen load.
The annual load of phosphorus on the Gulf of Bothnia is 7,900 tonnes, of which 2,600 tonnes comes from Sweden, 3,700 tonnes from Finland and 1,600 tonnes with atmospheric deposition. Discharge from Swedish pulp and paper industry contributed in 1991 with 270 tonnes of phosphorus, corresponding to 3% of the total phosphorus load.
The annual load of metals from Sweden, Finland and the atmosphere has been estimated at 3,200 tonnes of zinc, 14 tonnes of cadmium, 790 tonnes of copper and 300 tonnes of lead. The Swedish pulp and paper industry is assumed to be responsible for 2% of the zinc load, 4% of the cadmium load, 0.6% of the copper load and 0.6% of the lead load.
The objective of this paper is to inform about nutrient and metal sources, located in Sweden and Finland, and to discuss where pollution abatement ought to be initiated. The loads of nitrogen, phosphorus and metals from the Swedish pulp and paper industry are not negligible in comparison with other minor anthropogenic sources, but when compared, e.g. with the atmospheric deposition directly on the sea surface, the contribution is small. An integrated national and international strategy, with clearly defined priorities and responsibilities, is urgently needed. Such an approach is only possible if an understanding of ecological and economical processes is used to implement a policy that will lead to a sustainable society and development.
Pilot Plant Experience with an Aerobic Moving Bed Biofilm Reactor for Treatment of NSSC Wastewater
Authors: Broch-Due A. , Andersen R. , Kristoffersen O. 
Published: May 2018

Norske Skogindustrier A.S operates Sande Paper Mill A/S, a neutral sulphite semi-chemical (NSSC) corrugating mill. The mill currently discharges 1500 m3/day of wastewater containing 36 tonnes of COD and 15 tonnes of BOD7.
A pilot plant test programme to demonstrate the application of a moving bed biofilm process was initiated in 1991. The objective of the pilot plant study was to obtain high COD removal efficiency at high organic loads, i.e. 25 kg COD/m3·day. If this was possible, two unused oil tanks ( 2 × 1000 m3) at the mill could provide sufficient reactor volume for biological treatment of the mill wastewater.
The process tested was the KMT Moving Bed Process. This process was developed quite recently and had not been tested for the treatment of pulp and paper wastewater.
The process is based on using floating biofilm carrier elements with a large inside surface area.
The pilot plant at Sande Paper Mill included two reactors in series and a settling tank. Each reactor had a volume of 0.523 m3 and both were filled with elements to about 70%.
The pilot plant was operated continuously for seven months. The organic load was increased in increments from about 10 kg COD/m3·d to about 65 kg COD/m3·d on the first reactor.
Results show that it is possible to achieve high removal efficiency at high organic loads. At an organic load of about 25 kg COD/m3·d on the plant (i.e. 50 kg COD/m3·d on the first reactor), COD and BOD7 reductions through the pilot plant were 70% and 96% respectively. Toxicity removal was about 98% (Microtox). Sludge production was 0.2 kg TS per kg COD removed or 0.35 kg TS/kg BOD removed. The main part of the soluble COD removal took place in the first reactor where oxygen consumption was about 3 times higher than in the second reactor. Organic load of about 60 kg COD/m3·d on the first reactor is the upper limit for efficient operation of the KMT process when treating the NSSC wastewater. No clogging was observed during the test period and the process seems to be both stable and robust.
Evaporator Condensate and Caustic Extraction Liquor from a Pulp Factory Treated with an Anaerobic Process
Authors: Nilsson B. , Strand O. 
Published: May 2018

Borregaard Industries Ltd, Norway, is a Ca-bisulphite based pulp manufacturer which has an interest in an anaerobic wastewater treatment process. At this pulp factory a combination of sulphite evaporator (SEC) and caustic extraction liquor (CEL) would eliminate the costs for neutralization chemicals in an anaerobic treatment process. The anaerobic process was also suitable because of the high concentration of organic compounds in CEL, the biogas production and the low sludge growth.
Today a full-scale plant treating SEC in combination with CEL is in operation with a capacity to treat 60 tons of COD/d. All CEL qualities are treated anaerobically even those containing peroxide. The highest guaranteed AOX concentration in the CEL to be treated is 25 mg AOX/I.
The experience from a 2-year pilot plant study has influenced the design of the full-scale plant.
An adaption of the sludge to the CEL has to be performed due the toxic compounds in the CEL.
The incoming wastewater to the full-scale plant has a composition of 50% COD from the SEC and 50% COD from the CEL. With an organic load of 40 tons COD/d, a SEC/CEL ratio of 51/49, the COD reduction is 65% and the gas yield 0.20 m3 CH4/kg COD added.
This full-scale plant is unique due to the treatment of different CEL qualities and to the high combination of CEL.
Treatment of Paper Mill Sludges by Low Temperature Wet Oxidation
Authors: Andersen R. , Munck J. , Knudsen L. 
Published: May 2018

The work presented in this paper concerns the application of low temperature wet oxidation for volume reduction of settled and floated sludges resulting from the treatment of waste water from a pulp and paper mill in Norway.
The results of batch and continuous pilot-scale tests show that it is possible to obtain reductions of more than 50% of COD and more than 70% of suspended solids by a mild treatment at 200°C and a retention time of only 20 minutes. This retention time is very short compared to conventional wet oxidation treatment applied to conditioning of organic sludge, which may lead to a reduction in reactor size and lowering of construction costs. The product obtained after wet oxidation has excellent dewatering characteristics resulting in a sludge volume reduction of 80% by sedimentation. The dewatered sludge can be further processed by acid treatment for recovery of alumina used for chemical precipitation of the sludge. The results show that it is possible to recover more than 80% of the alumina present in the sludge. Tests of recovered alumina show a flocculation efficiency comparable to that of virgin alumina.
First months operation of two biofilter prototypes in the waste water plant of acheres
Authors: Vedry B. , Paffoni C. , Gousailles M. , Bernard C. 
Published: May 2018

In order to preserve the River Seine against point discharge of secondary effluent, the purification plant of Achères is building a tertiary step to nitrify and polish secondary effluent by biofiltration, the dry weather flow of which reaches 2 100 000 m3/day.
Two biofilter prototypes, Biofor and Biostyr, have been created to test their performances in a wide range of operating conditions, especially in the case of storm water. First results show that a removal of 0.8 kg N-NH4/m3.d, corresponding to a Global Oxygen Demand removal of 5.5 kg O2/m3.d, can be achieved by Biofor at a temperature of 14°C.
The Biostyr prototype brought later into service has not yet enough results to draw clear conclusions. Nevertheless the first data during May 1993 (temperature 18.5°C) are also very promising.
Tertiary nitrification in pilot-plant plug-flow fixed-film reactors with long-term ammonium deficiency
Authors: Fruhen M. , Böcker K. , Eidens S. , Haaf D. , Liebeskind M. , Schmidt F. 
Published: May 2018

The objective of this study is to investigate to what extent the nitrification capacity of a pilot-plant fixed-film reactor changes during extensive periods of nutrient supply deficiency. The examined pilot-plant was an upflow reactor filled with swelling clay of medium grain size (6 to 8 mm).
The experiments revealed that the maximum nitrification rate remained practically constant during the first weeks after the onset of unregulated ammonium supply. The capacity declined slowly, dropping to approximately 66% of the initial capacity after about ten weeks. Still ammonium peaks of up to 8 mg/l were readily nitrified throughout the entire period of the experiment. The reduction in nitrification capacity during the observation period did not result from decay processes of biomass but from the reactor becoming blocked and thus hampering transfer processes. It could be observed that the detached organisms attached again further up.
This semi-industrial project demonstrated that a plug-flow fixed-film reactor can be used as effective means of tertiary nitrification.
Paper mill effluent treatment using biofiltration
Authors: Rovel J. M. , Trudel J. P. , Lavallée P. , Schroeter I. 
Published: May 2018

The results achieved on industrial effluents from four different paper mills, ranging from highly diluted effluents from units for the production of fine papers using bleached cellulose, to much more concentrated effluents from an integrated pulp and paper plant, show the potential and advantages of the Biofor process.
Implemented as a complement to or replacement for activated sludge systems, the BioforR process, which dispenses with the clarification step and offers excellent resistance to sudden load and flow rate variations, is particularly well suited to the needs of this industry. This explains the rapid success already achieved in Europe and expected soon in North America.
Chemical process wastewater treatment by attached cultures under anoxic conditions
Authors: Delanghe B. , Roussy J. , Guibal E. , Le Cloirec P. 
Published: May 2018

The anoxic biodegradation of organic carbon in industrial wastewaters was studied on pilot plants with attached bacteria. The process involved submerged granular filters with expanded glass balls as packing material. The two wastewaters which were investigated came from a wine-produce industry and a chemical industry.
The nitrate requirements were studied on a semi-batch pilot plant. The nitrate consumption was found to be about 0.7 - 0.9 g N-NO3·g−1TOC for the organic carbon removal from the wine-produce industry wastewater.
The influence of the volumetric load, Cv, on the Total Organic Carbon (TOC) removal was studied on a continuous-flow pilot plant. High removal yields of 90 % and more were obtained with volumetric loads up to 2 kg TOC.m−3.d−1 with the wine-produce industry wastewater. However 80 % TOC removal was obtained for a maximum volumetric load of 0.2 kg TOC.m−3.d−1 with the chemical industry wastewater. The difference between the two wastewaters might be due to the different degradation kinetics and/or biodegradability of their organic compounds. Nitrite concentrations were negligible throughout the study.
Adaptive water management: integrated water management on the edge of chaos
Authors: Geldof Govert D. 
Published: May 2018

To give form and content to integrated water management, we often apply an internal approach, based on the component parts. With this approach we encounter at least three problems: the problem of scale, the problem of level and the problem of assessment. We can solve these problems by applying an external approach to integrated water management, in addition to the internal approach. This is possible by application of the theory of complexity. It turns out that we can describe the sum of the processes within integrated water management as a complex adaptive system, a learning and evolving system. If we use this system as a model, we come to the insight that we must not try to achieve as much order as possible, but that we have to look for a good balance between order and chaos. If we find that balance, we are able to adapt water management to the ever changing surroundings.
The usefulness of the approach becomes clear if we look at the discussion in urban water management about the applicability of source control and end-of-pipe techniques. The approach provides a strategy for handling uncertainties.
A simplified model for thermal discharges
Authors: Öztürk I. , Sarikaya H. Z. , Aydin A. F. , Demir I. 
Published: May 2018

In this study a two-dimensional model has been developed in order to estimate the distribution of temperatures in the marine environment following the discharge of thermal effluents. The model is applicable to any type of marine environment; stratified or uniform. Any density or salinity profile can be handled for the stratified environment. The water column above the diffuser port is divided into a number of layers with thicknesses of 1 or 2 m, depending on the salinity and temperature data and the sea water density is assumed to be uniform within each layer. The average and the minimum dilutions and the average and maximum temperatures are calculated at each layer for the rising plume from port to the trapping level by iterative application of the model equations. This way a diffuser design which satisfies the regulations becomes possible.
The model also predicts the dilutions and the temperatures due to subsequent dispersion which occurs during the transport of the field from the seawater surface or from the trapping level depending on the currents and turbulence. The heat transfer between the thermal plume and the ambient seawater is neglected to be on the safe side especially in evaluation of the environmental impact of the thermal discharges. The computer program called THERMOD not only calculates the dilutions and the temperatures, but also draws the contours of equal temperature and temperature differantial (ΔT) lines.
The model has been succesfully used in Environmental Impact Assesment Studies of the two 500 MW power plants proposed at the east of Marmara Sea, Turkey.
An operational survey of a natural lagoon treatment plant combining macrophytes and microphytes basins
Authors: Vandevenne Louis 
Published: May 2018

The sewage treatment plant studied, located in a rural area, is designed to treat the wastewater for a population of 650. The station functions in accordance with the principle of natural lagoons via artificial wetlands combining macrophytes and microphytes lagoons arranged in series. The overall surface area including the primary lagoon gives rise to a specific load of 6 m2/inhabitant.
Both the primary and secondary treatments produce a very good water quality in accordance with the conventional parameters (SS, Suspended Solids; BOD5, the Biological Oxygen Demand over a 5 day period; COD, the Chemical Oxygen Demand). The tertiary purification of the nitrogen and phosphorus does not give as good results as expected, respectively 42% and 35% removal; very little better than those of a conventional installation. The tertiary quality standard appears not to be attainable since the successive biological mechanisms carrying out the elimination process are followed by a release of the pollutants and an insufficient elimination (plant exportation) by the macrophytes. The design and management of the macrophytes basins is relatively tricky, particularly with respect to the removal of weeds and the regulation of the water level in the macrophytes basins.
Constructed wetlands in Europe
Authors: Haberl R. , Perfler R. , Mayer H. 
Published: May 2018

Many European countries have recently stated an increasing demand for small waste water treatment plants. Constructed wetlands seem to be particularly well suited for on-site treatment due to their simple construction and large buffering capacity.
A number of different designs exist in Europe, above all subsurface flow systems, which have been in use for 20 years. At first, horizontal flow was preferred but the stringent legal rules have led to the development of highly efficient vertical flow in recent years. In order to meet the higher requirements of small and very sensitive recipients, combined systems (i.e. constructed wetlands and conventional biological plants) have proved to be successful. At present, tests are being carried out to study the use of constructed wetlands for other applications as well, such as the treatment of groundwater, industrial waste water and sludge dewatering.
All our present know-how and experience with constructed wetlands should enable us to convince the authorities and to obtain legal permission for the installation of constructed wetlands.
The reality of sewage treatment using wetlands
Authors: Hiley Peter D. 
Published: May 2018

Empirical performance data provide a basis for the design of wetlands to specific performance limits. BOD and suspended solids are removed up to 95% from 10-250 mg l−1. Surface flow systems in Yorkshire achieved higher effluent standards but generally lower mass load removal than subsurface flow systems. All wetland systems fill up with solids at a predictable rate, and if they are not removed or degraded, they will overflow. Ammonia is not normally oxidised, except where relatively large land areas are used and/or BOD falls below 20 mg l−1. Phosphate is accumulated until saturation. Bacteria (faecal indicators) are removed, sometimes almost completely, but not reliably. The established theoretical knowledge of sewage treatment processes explains the performance of wetlands. Plants provide a renewable support medium for microbial growth, a matrix to retain solids and assist plug flow hydraulics, but do not appear to provide oxygen. BOD removal is mainly by the aerobic breakdown of organic matter. Bacteria growing on the soil and f-horizon (litter layer) use oxygen from the atmosphere and from nitrate in the sewage. Wetlands are oxygen limited and performance is enhanced if extra aeration is provided.
There were no obvious performance differences between surface and subsurface flow systems, unless extra aeration was involved, though strict comparative data were not found. Vertical flow wetlands appear to be inefficient percolating filters. The simplest designs, construction methods, maintenance and rejuvenation methods should be used. Near design performance of surface flow wetlands is achieved in about 14 days.
Light adaptation of oscillatoria agardhii at different time scales
Authors: van Duin Elisabeth H. S. , Aalderink R. Hans , Lijklema Lambertus 
Published: May 2018

The Markermeer is a eutrophic shallow wind exposed lake. In contrast to other eutrophic lakes in the area, persistent blooms of the cyanobacterium Oscillatoria agardhii do not occur. The severe variations in the available light energy, caused by an excessive resuspension of sediment, are held responsible for this absence. Field experiments were conducted in the Markermeer, to investigate the relations between O. agardhii and the specific light climate in the Markermeer, emphasizing the adaptation rate and extent to light energy level variations.
In experiments with traditional light and dark bottles, and bottles moving up and down the water column it was observed that vertical mixing tended to increase the net production of oxygen, as the exposure time near the water surface is too short to cause light inhibition. From experiments with a vertical perspex tube it was concluded that during days with maximum hourly light energy levels above 200 μE·m−2·s−1, the light utilization efficiency was much higher in the morning hours than during the afternoon. This phenomenon did usually not occur at days with lower mean irradiance levels. After prolonged periods of low energy levels (below 50 μe·m−2·s−1), the light utilization efficiency increases significantly but the maximum production level does not increase.
The disinfection of municipal wastewater by ultraviolet light: a French case study
Authors: Perrot J. Y. , Baron J. 
Published: May 2018

A disinfection installation using the Ultraviolet technology (Trailigaz/Trojan, series UV 3000) was installed at the end of May 1994 at the new Outreau-Le Portel (Pas de Calais) municipal wastewater plant, the outflow of which flows into the sea near Le Portel beach. Such a unit is the first of this type in France. The installation is described. The disinfection guarantees are an outflow the germ concentration of which should be below 200 Escherichia coli/100 ml geometric average over 30 days, and below 2000 E. coli 100% of the time. The results obtained from 1 June to 3 October are specified.
The disinfection performance was highly satisfactory: the mean residual Escherichia coli and faecal streptococcus values were 43 and 42 germs/100 ml for kills of 3.2 and 2.8 u.log. The disinfection guarantees have never been exceeded. In particular, only 2 samples out of 58 taken showed an E. coli concentration after UV greater than 1,000 germs/100 ml. The UV transmission (T) of the effluent varied from 35 to 63% as a consequence of the station's output increase. The least satisfactory results were recorded during periods of lower % UV T. During the 4 months of the study, three acid washes were carried out of the quartz sleeves: the speed at which the UV system used at Le Portel (low pressure UV lamps in an open channel) is contaminated is thus low.