bluuebunny/crossref_metadata_2025_split huggingface dataset:
Considerations on Water, Oil and Air in Porous Media
Authors: Schiegg H. O. 
Published: May 2018

Oil, a hydrocarbon spilled above a phreatic aquifer, initially percolates primarily vertically until it reaches the capillary fringe. Subsequently, the oil migrates within the capillary fringe parallel to the groundwater table thereby creating an oil-polluted layer parallel to the groundwater table. The mean thickness of such an oil-polluted layer is denoted by .
The objective of this paper is to describe as a function of the thickness of oil in an observation well and of the oil potential, respectively. For oil to enter a porous medium, a minimum value of is necessary and will be determined.
The paper starts by explaining the relationship between the water-air saturation curve and the saturation curves for water-oil and oil-air as expressed by the scale factor Ω. Subsequently, the phenomenon of capillary pollution is described. The influence of hysteresis in capillarity on the above considerations is shown at the end of the paper.
The Selective Cultivation of Easily Harvestable Algae Using Crossflow-Microscreening
Authors: Pretorius W. A. , Hensman L. C. 
Published: May 2018

The implementation of algal systems as a viable wastewater treatment option has been seriously limited by the availability of cost effective techniques for removing algae from the effluent stream. In this study, the problem of biomass separation was overcome by the selective cultivation of algae species which could be removed effectively by simple screening. The selection of desired species was achieved by a combination of short hydraulic space time and various size micro-screens operating as algae selectors on the effluent stream. A high rate algae growth system, in which the mean cell residence time and hydraulic space time could be manipulated independently, was developed.
With humus tank effluent as feedstock, a hydraulic space time of 10 hours and a 200 µm opening size crossflow-microscreen, the filamentous green algae, Stigeoclonium, became the dominant species. This selected culture could be readily maintained at any predetermined concentration in the system with less than 20 mg/ℓ suspended solids in the effluent. The biomass produced was exceptionally easy to harvest.
Biological Phosphorus and Nitrogen Removal at an Experimental Full Scale Plant in the U.K.
Authors: Best A. G. , Hatton C. J. , Rachwal A. J. , Hurley B. 
Published: May 2018

A three year project to improve the performance of a conventional diffused air activated sludge plant was carried out on a 4000 m3/day stream at the Basingstoke Sewage Treatment Works of Thames Water Authority from 1981-1984.
The modified plant named ROTANOX comprised the use of rotary flow through two adjacent aeration lanes with the introduction of an anoxic section for denitrification.
In the last 12 months of the study an anaerobic zone was created at the front of the plant and, after establishment of the necessary operating conditions, biological phosphorus removal was monitored.
An effluent with a mean of 4 mg/l BOD, 11 mg/l SS and 2 mg/l NH3-N was achieved during the first two years of operation and energy consumption was reduced by 15%.
In the final year a mean total P removal of 5.7 mg/l was recorded with the highest monthly average being 10 mg/l removal. This was equivalent to mean percentage removal of 40% and 47% respectively.
Air Chemistry Observations in the Canadian Arctic
Authors: Hoff R. M. , Barrie L. A. 
Published: May 2018

Arctic air chemistry measurements made in Canada since 1979 are reviewed. At Mould Bay, Alert and Igloolik, 25 aerosol constituents and aerosol light scattering have been measured routinely. Gas phase measurements of SO2, chlorinated pesticides, nitrogen species, and hydrocarbons have been measured during short-term intensive studies. CO2 has been routinely measured as part of the background air monitoring program at Mould Bay and Alert.
Anthropogenic pollution typified by SO4= and V has a persistent seasonal cycle seen at all sites. Alert tends to have slightly higher concentrations than Mould Bay and Igloolik. It is shown that the seasonal cycle is dependent on the source of the aerosol. Anthropogenic pollutants (Cr, Cu, Mn, Ni, Pb, Sr, V, Zn, H+, NH4+ , SO4= and NO3−), halogens except Cl (Br, I, F) , sea salt (Na, Mg, Cl) and soil derived constituents (Al, Ba, Ca, Fe, Ti) have distinct seasonal cycles. Anthropogenic constituents (except SO4=) have peak concentrations in winter 1/2 to 1/4 of annual means in southern Sweden. SO4 is an exception to this being only 30% less in the Canadian Arctic than in southern Sweden, because of the production of SO4= from SO2. Light scattering observations indicate that SO4= varies from 10-70% of the total fine particle mass during the polluted winter months. Light scattering coefficients (bscat) greater than 5 × 10−5 m−1 at Mould Bay are associated with trans-polar air trajectories. Weekly-mean SO2 concentrations at Mould Bay between late 1983 and early 1984 ranged from 0.2-0.8 ppb and comprised 48-82% of the airborne sulphur. Recent measurements of chlordane in the Arctic atmosphere are presented.
Reuse of Wastewaters in Agriculture by Means of Sprinkler Irrigation on a Farmland Area of 3000 ha – Large Scale Experience in Germany
Authors: Boll R. , Kayser R. 
Published: May 2018

The Braunschweig wastewater land treatment system as the largest in Western Germany serves a population of about 270.000 and has an annual flow of around 22 Mio m3.
The whole treatment process consists of three main components : a pre-treatment plant as an activated sludge process, a sprinkler irrigation area of 3.000 ha of farmland and an old sewage farm of 200 ha with surface flooding.
This paper briefly summarizes the experiences with management and operation of the system, the treatment results with reference to environmental impact, development of agriculture and some financial aspects.
Effects of Sewage Outfalls on Intertidal Ecosystems in Kuwait
Authors: Literathy P. , Nasser Ali L. , Zarba M. A. , Puskas K. 
Published: May 2018

Kuwait City has an impact on the nearshore marine environment by discharging sewage randomly through short emergency outfalls into the intertidal zone. The effect of the discharged sewage on the biological activity and the chemical characteristics of the relevant intertidal areas, which are controlled by a dry, tropical climate, was studied.
Pore water, tidal water characteristics and nutrient release and transport from the intertidal zone during tidal flushing were investigated in polluted and unpolluted areas. The accumulation of particulate organic matter in the upper, middle and lower intertidal zones was characterized. It was concluded that in addition to settling, a great deal of particulate organic matter entered into the upper tidal sediment by infiltration during high tide and was filtered out by the sediment and migrated toward the low tide zone during the falling tide. The rate of the release of the substances associated with inorganic particulates was controlled by the overall organic load and the microbial activity. Sediment core samples were taken for multistage carbon dioxide treatment, and the results showed a decrease in carbonate-bound phosphates with depth. Photosynthetic productivity observed during the spring showed a close relationship with the sewage discharges and were also controlled by the tidal current. Based on the determination of dissolved nutrients, it was concluded that the limiting nutrient for photosynthesis was nitrogen rather than phosphorous. The release of some heavy metals from the sewage-polluted intertidal sediment was significant, and beachrock development also related to the discharges. The intertidal fauna was impoverished because of the organic sludge.
Technical Aspects and Cost Estimations for Anaerobic Systems Treating Vinasse and Brewery/Soft Drink Wastewaters
Authors: Craveiro A. M. , Soares H. M. , Schmidell W. 
Published: May 2018

Anaerobic digestion of industrial and domestic wastewaters is an effective way of alleviating pollution problems. The treatment of vinasse, a residue of ethanol fermentation, and brewery/soft drink wastewaters was investigated by IPT for several years. This paper presents data and discusses the technical and economical feasibility of treating these wastewaters using UASB reactors.
With vinasse, it is possible to operate industrial plants with organic loading rates exceeding 15 kg COD m−3 day−l, removing 95% of the initial BOD. The produced gas can be used as a substitute for diesel oil in vehicles and also to produce steam, replacing bagasse. The pay-back period of the capital investment is estimated at around 4 to 5 years.
For brewery/soft drink wastewaters, it is possible to operate UASB reactors with a HRT of 6 hours, removing more than 90% of the initial BOD. The reactor showed a good capacity to handle temperature shocks.
Capital investments for both cases are presented in terms of total investment per kg of COD and m3 of reactor installed.
Sediment Mobility and its Contribution to Trace Metal Cycling and Retention in a Macrotidal Estuary
Authors: Morris A. W. , Bale A. J. , Howland R J. M. , Millward G. E. , Ackroyd D. R. , Loring D. H. , Rantala R T. T. 
Published: May 2018

Measurements of trace metals in the dissolved, suspended particulate and sediment phases of the Tamar Estuary have been combined with observations of sediment and suspended particle mobility in an interpretation of metal cycling and retention processes within the system.
Dissolved metal distributions indicate pronounced estuarine metal reactivity involving net removal onto suspended particles in the low salinity, high turbidity zone and net input from the sediment in the middle estuary. These processes are not reflected in the metal contents of suspended particulate material and superficial sediment, although the dissolved metal variations are a product of particle-water exchanges. This apparent anomaly is attributed to the magnitude of internal resuspendable particle fluxes within the system. Consequently, temporal and spatial variabilities in the composition of suspended particulate material and superficial sediment are determined by physical rather than chemical processes.
The Impact of Tributyl Tin (TBT) Antifouling Paints on Molluscan Fisheries
Authors: Thain J. E. , Waldock M. J. 
Published: May 2018

Laboratory and field experiments carried out during 1982–84 confirmed that some UK estuaries contained sufficient organotin compounds to cause reduced meat yields and shell thickening in the Pacific oyster, Crassostrea gigas.
Historically the European flat oyster, Ostrea edulis, has been the basis of an important fishery on the east coast of England but the population has recently declined to an all-time low. Laboratory experiments have been carried out to compare larval survival, growth of spat and the development of gametes in adult O. edulis, and the growth of spat of four other bivalve species in the presence and absence of organotin toxins. The results from these experiments are discussed in relation to the concentrations of organotin compounds in samples of water and oyster tissues, from several sites in the UK, and the reproductive behaviour of adult oysters from natural stocks in the Crouch/Roach estuary system.
The data strongly suggest that TBT is at least a contributory factor and probably a major cause of the failure in recent years of O. edulis to reproduce naturally in the Crouch Estuary.
The UK Government has proposed legislation to control and reduce organotin emissions into the marine environment and this is briefly outlined.
Towards an Affordable Human Waste Management Programme for the Poor – A Report on Bangladesh
Authors: Minnatullah K. M. 
Published: May 2018

Nearly 80% of all illness in Bangladesh is related to water and sanitation. The combined rate of enteric diseases in Bangladesh is the highest in the world. 30% of all the deaths of children under 5 are due to diarrhoea, claiming more than 200,000 lives annually. Environmentally sound human waste management, along with personal hygiene awareness, are of critical importance to the prevention of faecal-oral disease transmission. present rural sanitation coverage is about 3%. A national target has been set to ensure that 13% of the rural poor will be covered under the human waste management programme by 1990, the end of the U.N. Water Decade. This however, contrasts with the similar target of 77% for the rural water supply programme, which received higher resource allocation and priority for a much longer period. This lack of correlation between water and sanitation has highly reduced the positive health impact of these developments.
An affordable human waste management programme for the rural people, where 87% of the total population lives under conditions of the greatest poverty and underdevelopment, urgently needs serious and realistic consideration in the context of the limited resource prospects for future years.
This report addresses the above issues and describes the commendable momentum that has been gained through the continuous efforts of national planners and policy makers. It is hoped that this might in the near future, through the rural human waste management programme, produce the long desired continual reduction of faecal-oral disease transmission.
Wastewater Sludge: Parasitological and Virological Contamination
Authors: Schwartzbrod J. , Mathieu C. , Thévenot M. T. , Baradel J. M. , Schwartzbrod L. 
Published: May 2018

Different types of sewage sludge produced during wastewater treatment and after storage of up to 5 years were analyzed for both virus and parasite eggs.
Among the 145 samples examined, 87.6 % were positive for either Nematode and/or Cestode eggs. Anaerobic digestion of the sludge had little influence on the numbers of helminth eggs while conditioning with lime plus ferric chloride reduced the egg recovery. Helminth eggs were found in sludge samples stored for 1–2 or 3 years, but none were found in samples stored for 4 years or more. None of the Ascaris eggs tested were viable.
Out of the 57 sludge samples examined for virus, all the biological sludges contained enterovirus, while only 44 % of the digested sludge samples and 10 % of the semi-dehydrated and conditioned (lime plus ferric chloride) sludge samples were positive for enterovirus. No virus were found in stored sludge.
Epidemiological studies are necessary in order to determine any risks presented to public and animal health by the agricultural use of the sewage sludge.
Landfarming of Oily Wastes: Design and Operation
Authors: Amaral S. P. 
Published: May 2018

The technology of treatment through landfarming for oily wastes has been more and more often utilized in Brazil, always successfully.
The definition, the processes which occur, as well as the factors which affect its performance are herein presented.
Design parameters, such as location, ground characterization, dimensioning of the area of application, groundwater protection, drainage, treatment of surface runoff water and percolated liquid, among others, are presented.
Operational procedures and quality monitoring of effluents and environment are also described.
PETROBRÁS is already operating two landfarming systems and has several others in the design stage.
We present data from these projects and report that oily waste degradation has been achieved in around six months.
Finally, we expect to be contributing to the affirmation and development of this technology in our Country.
Sewage Treatment in Helophyte Beds–First Experiences with a New Treatment Procedure
Authors: Bucksteeg K. 
Published: May 2018

Waste water treatment in helophyte beds under humid climate conditions has been favoured by some German ecologists for some years. The idea is to cause waste water to flow horizontally through the root zone of helophytes to achieve satisfactory effluent properties. There exist many highly different proposals regarding the choice of soil and helophytes to be applied, bed area, design of inlets and outlets and operation conditions. A few plants have been operated in practice for some years. It appears that clogging is one of the main problems occurring in these plants.
The hydraulic uptake capacity of soil is discussed in Darcy's law. Comparisons with observations of plants in operation are drawn. The interactions between soil properties, its uptake capacity, BOD5-, COD-, N- and P-reduction are evaluated. The effluent results of helophyte beds are compared with those of low-loaded trickling filters and of ponds used for sewage treatment in small villages in rural areas of Germany. It has been proved that the total construction costs of sewage treatment plants with helophyte beds used as the biological stage are higher when compared with those of conventional plants in general.
Treatment of Wastewaters from the Tomato Concentrate Industry in High Rate Algal Ponds
Authors: Rodrigues A. M. , Santos Oliveira J. F. 
Published: May 2018

High rate algal ponds are an important process of biological treatment used either for domestic sewage or food industries effluents and to produce single cell proteins.
The results refer to the efficiency of treatment of wastewaters from the tomato concentrate industry and determination of the chemical composition of “Albazod” (microbial biomass) harvested in a pilot system of high rate algal ponds installed in the Department of Environmental Engineering, Faculty of Sciences and Technology, New University of Lisbon, at Monte da Caparica.
Depending on the detention time and period of the year, the following removal efficiencies were obtained: COD 68.1 – 94.6%; TOD 57.6 – 85.0%; N-NH4+ 89.4 – 96.2%; colour 29.6 – 91.7% and turbidity 37.2 – 92.7%. Albazod separated from the effluent has a high nutritive value for low detention times (crude protein values of 31.50% and 30.75% dry matter for 4 days and 5 days of detention time, respectively). The highest productivity value was 30.82 g of dry matter/m2/day and was obtained for a detention time of 4 days.
Activated Sludge Settlers: Design and Optimization
Authors: Catunda P F. C. , van Haandel A. C. 
Published: May 2018

Activated sludge settlers perform two functions simultaneously: clarification and sludge thickening. Depending on the values of the mixed liquor and return sludge concentrations and on the sludge settling characteristics either one of these functions may limit the solids loading rate that can be applied to the settler, which in turn determines the required settler surface area.
A method is developed to establish which of the two functions is determinant for the maximum solids loading rate in a particular design situation. Expressions are derived to calculate the required settler surface area for clarification and for thickening. These expressions are based on the experimentally verfied supposition that the zone settling velocity decreases exponentially with increasing suspended solids concentration. A graphical method to determine the optimal mixed liquor and return sludge concentrations for minimum construction and operational cost is presented.
An Assessment of a Low-Cost Wastewater Disposal System after Twenty-Five Years of Operation
Authors: Reidy B. L. , Samson G. W. 
Published: May 2018

A low-cost wastewater disposal system was commissioned in 1959 to treat domestic and industrial wastewaters generated in the Latrobe River valley in the province of Gippsland, within the State of Victoria, Australia (Figure 1). The Latrobe Valley is the centre for large-scale generation of electricity and for the production of pulp and paper. In addition other industries have utilized the brown coal resource of the region e.g. gasification process and char production. Consequently, industrial wastewaters have been dominant in the disposal system for the past twenty-five years. The mixed industrial-domestic wastewaters were to be transported some eighty kilometres to be treated and disposed of by irrigation to land.
Several important lessons have been learnt during twenty-five years of operating this system.
Firstly the composition of the mixed waste stream has varied significantly with the passage of time and the development of the industrial base in the Valley, so that what was appropriate treatment in 1959 is not necessarily acceptable in 1985.
Secondly the magnitude of adverse environmental impacts engendered by this low-cost disposal procedure was not imagined when the proposal was implemented. As a consequence, clean-up procedures which could remedy the adverse effects of twenty-five years of impact are likely to be costly.
The question then may be asked - when the total costs including rehabilitation are considered, is there really a low-cost solution for environmentally safe disposal of complex wastewater streams?
Development and Optimization of a Process Combination of a Highest-Loaded Activated Sludge Stage and Biologically Intensified Filtration
Authors: Firk W. , Ghandehari N. 
Published: May 2018

Conventional sand- and two-layer filtration is frequently put into action for the purpose of advanced wastewater treatment after low-loaded activated sludge systems. However, the effectiveness of this conventional filter concerning the biological content which is difficult to degrade (measured by COD) is extremely low - and the costs too high. In direct comparison, modifying the filters to a biologically intensified system, brings about a substantial increase in efficiency while costing very little more.
The investigations of the authors for the optimization of the whole system, consisting of an activated sludge process and a biologically intensified filter, led to the fact that for the requirements of advanced treatment, the size of the activated sludge stage can be substantially reduced, without the effectiveness of the system as a whole being affected.
In the field of normal requirements (national effluent standards) and comparable low influx concentrations, biologically intensified filtration can be combined with a high-loaded activated sludge process of SLR up to 5 kg BOD5/(kg MLSS.d). The area required for the construction of the system is under 50% compared to the conventional one-stage activated sludge system.
At higher influx concentrations the simultaneous addition of precipitants/flocculants to the high-loaded activated sludge stage, leads to substantial improvement of the effluent of the whole system and simultaneously to a distinct phosphorus elimination. This process modification is greatly advantageous, especially for densely populated lake areas.
The oxygen supply system of the filter has a key function in connection with the influent concentration and the loading of the biological stage.
Investigations of Chlorinated Thiophenes: A Group of Bioaccumulable Compounds Identified in the Effluents from Kraft Bleaching
Authors: Carlberg G. E. , Johnsen S. , Landmark L. H. , Bengtsson B.-E. , Bergström B. , Skramstad J. , Storflor H. 
Published: May 2018

By comparison with six synthesized standards the identity of the following chlorinated thiophenes were established in spent kraft bleach liquors: 2,3,4-trichlorothiophene and 3-formyl and 3-acetyl di- and trichlorothiophene. The synthesized standards were found to be isomers of the thiophenes identified in the effluents. A large number of lipophilic terpene derivatives with from one to four chlorine atoms were also detected.
The synthesized chlorinated thiophenes were found to have partion coefficients (Log Pow) between 3.8 and 5.6. The compounds were found to bioaccumulate in bleak. About one third of the concentrations at the end of the exposure period remained in the fish after an elimination period of 14 days. The compounds were moderately toxic towards the harpacticoid Nitocraspinipes. Three of the compounds showed mutagenic activity.