bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Pollutant Specific Models for Toxic Organic Compounds in the Activated Sludge Process
Authors: Watkin Andrew T. , Eckenfelder W. Wesley
Published: May 2018

The concept of pollutant specific models in completely mixed biological recycle reactors is developed. Pollutant specific Monod constants are developed by considering substrate utilization, cell growth, and endogenous decay rates based solely on influent and effluent specific pollutant concentrations. In this way, models are developed which predict specific pollutant removal in biological reactors. Three nonvolatile compounds are evaluated; namely, phenol, 2,4-dichlorophenol, and 2,4-dinitrophenol and their respective specific Monod constants determined. A pollutant specific model for concurrent biodegradation and volatilization is also developed. A mathematical method for evaluating the pollutant specific Monod constants independent of volatilization kinetics is derived for the volatile compounds dinitrobenzene and carbon tetrachloride. Control strategies are discussed which emphasize the rate limiting pollutant concept. Conclusions are drawn as to the applicability and limitations of pollutant specific models.
Wastewater Treatment by Artificial Wetlands
Authors: Gersberg R. M. , Elkins B. V. , Goldman C. R.
Published: May 2018

This report describes studies of artificial wetlands at Santee, California which demonstrate the capacity of these systems for integrated secondary treatment (BOD and suspended solids removal) and advanced treatment (nitrogen removal) of municipal wastewater effluents. When receiving a blend of primary (1°) and secondary (2°) wastewaters at a blend ratio of 1:2 (6 cm per day 1° : 12 cm per day 2° ), mean removal efficiencies for a complete year of operation from July, 1982 through July, 1983 were 80% for total nitrogen (TN) and 80% for total inorganic nitrogen, with the mean inflow TN level of 21.5 mgl−1 reduced to a mean value of 4.3 mgl−1 in the wetland effluent. The BOD and suspended solids removal efficiencies were 93% and 88% respectively. The mean wetland effluent values for both BOD and suspended solids were below the 10/10 mgl−1 standard for advanced secondary treatment. When primary effluent was the sole source of inflow to the artificial wetlands, BOD and suspended solids levels approaching the quality of a secondary treated effluent (30/30 mgl−1) could be attained at an application rate of 6-8.3 cm per day. In this case, mean BOD and suspended solids removal efficiencies for the complete year from July, 1982 through August, 1983, were 78% and 80% respectively, with the effluent levels reduced to mean values of 33 mgl−1 for BOD and 10 mgl−1 for suspended solids. At the application rate of 6 cm per day, our study shows that only 16 acres (6.5 ha) of constructed wetlands would be required to treat 3785 m3 of primary wastewaters to secondary treatment levels. Data on capital and O&M cost show that artificial wetlands are competitive with other treatment technologies available to small to medium sized communities.
Colloidal Stability of Particles in Lakes: Measurement and Significance
Authors: Ali Waris , O'Melia Charles R. , Edzwald James K.
Published: May 2018

The stability of natural particles in a lake water is determined and effects of solution characteristics on particle stability are examined. Model simulations of the effects of particle stability, solid-solute partitioning, and hydraulic loading on the transport and fate of particles and associated pollutants and nutrients are presented.
Sorption of Ammonia Nitrogen on River Borne Suspended Solids
Authors: Wukasch R. F. , Moos L. P.
Published: May 2018

The ammonia nitrogen carrying capacity of Wabash River suspended solids was evaluated. The sorption of ammonia onto these solids was found to follow a Langmuir model and to be reversible. At background river ammonia concentrations of below about 0.2 mg l−1, sorbed ammonia carried by the suspended solids is quite low, less than 0.2 mg NH3-N per gm suspended solids. However, near outfalls under the right conditions, as much as 15 to 20% of the ammonia discharged may be initially sorbed from solution to be later released downstream when the soluble ammonia concentration decreases.
Restoration of Lake Veluwe, The Netherlands, by Reduction of Phosphorus Loading and Flushing
Authors: Hosper S. H.
Published: May 2018

In the shallow and hypertrophic Lake Veluwe the cycling of phosphorus between water and sediments was mainly determined by a continuous bloom of the blue-green alga Oscillatoria agardhii. For the restoring of water quality it was considered necessary to reduce the external P-loading as well as to suppress the release of phosphorus from the sediments. The P-loading of the lake decreased from approx. 3 to 1 g P/m2 a year in 1979. Additionally the lake has been flushed during winter periods with water low in phosphorus. Flushing was primarily aimed at interrupting the continuous algal bloom. After four winters of intensified flushing Oscillatoria still is the dominant alga but the diversity of species is increasing. In 1982 Oscillatoria disappeared for several months.

The results show a sharp decline of summer values of total phosphorus from 0,40-0,60 mg/1 to approx. 0,15 mg/1. In the trend of various parameters correlated with algal biomass a striking discrepancy is observed.

Chlorophyll-a, ashfree-dryweight and particulate-phosphorus show a considerable and approximately similar decrease (50-60%). On the other hand the decrease of algal biomass in terms of freshweight (viz. biovolume of Oscillatoria) and reciprocal Secchi-disc values is relatively small (approx. 25%). Obviously the O. agardhii filaments contain much less organic matter, chlorophyll-a, phosphorus and nitrogen per unit of biovolume after implementation of remedial measures.

Transparency appears to be determined by number and volume of O. agardhii more than by chlorophyll-a and ashfree dryweight.

Intensified flushing will be continued for the next few years.
Treatment of Agro-Industrial Wastes Using Water Hyacinth
Authors: John C. K.
Published: May 2018

In Malaysia lagoon systems have been successfully adopted by the natural rubber (NR) and oil palm industries to treat their effluents. The possibility of using Eichhornia crassipes (water hyacinth) in the lagoons to further improve the treatment system was investigated. Good removal of pollutants from the block rubber effluent was achieved using a hydraulic retention of 10 - 15 days. The resulting effluent discharge was of acceptable quality. Water hyacinth also markedly improved the quality of the effluent from the remilling rubber factories. Consequently propagation of water hyacinth in the lagoons has been recommended.

Pilot plant trials with palm oil mill effluent (POME) have shown that water hyacinth can be successfully grown in anaerobically digested liquor removing 96% BOD, 87% COD, 96% suspended solids, 83% ammoniacal nitrogen and 97% oil and grease. It also removed more than 99% of the indicative bacteria such as coliforms, E.coli and Streptococci.

Under the Malaysian conditions, water hyacinth grew profusely yielding about 500 kg of dry matter per ha per day. The average dry weight was about 5.0% and it contained about 24% protein, 21% fibre and 14% ash.
Hazardous Substances in Waste Water
Authors: van Luin A. B. , van Starkenburg W.
Published: May 2018

The Governmental Institute for Sewage and Waste Water Treatment has studied the presence of a number of hazardous substances, selected by the EEC-Commission, in sewage and industrial waste water. The influent, effluent and sludge of six municipal waste water treatment plants and the waste water of 59 industries were sampled and analysed.

Volatile chlorinated hydrocarbons in sewage originate mainly from industrial discharges. Chlorophenols, γ-hexachlorocyclohexane, polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) appear to be present at a low and constant background in municipal sewage and in many industrial waste waters. The removal in the municipal treatment plants amounts to:-volatile chlorinated hydrocarbons 50–90%-hexachlorobenzene 95%-hexachlorocyclohexanes 40–65%-chlorophenols 20–40%-PCB about 90%-PAH 85–95%

This study has given a survey of emissions of these hazardous substances. The total emission of the examined substances in the Netherlands has remained out of the scope of this investigation.
The Calculation of Transport Coefficients of Phosphate and Calcium Fluxes Across the Sediment-Water Interface, from Experiments with Undisturbed Sediment Cores
Authors: van Raaphorst W. , Brinkman A. G.
Published: May 2018

Fluxes of phosphate and calcium across the sediment-water interface of six undisturbed cores are investigated. Attention is paid to the accuracy of porewater extraction and the influence of this sampling upon the experiments. From this, it is concluded that sampling time should at least be one day. Continuous and batch experiments resulted in a rapid release of phosphorus and calcium from the sediment. The influence of induced seepage could not be shown. On a theoretical base, it is concluded that the benthic fluxes are fed by desorption at or just below the interface, rather than by diffusion from deeper layers. Hence, data of interstitial water could not directly be used for calculating the driving forces of these fluxes. Instead, endconcentrations in the overlaying water of the batch experiments are used, which resulted in values of transportcoefficients of 3–10.10−7 m.s−1, being in good agreement with theoretical as well as field data.
The Role of Rapid Mixing Time on a Flocculation Process
Authors: François R. J. , Van Haute A. A.
Published: May 2018

The influence of the duration of rapid mixing on a flocculation process is evaluated by investigating the characteristics of the hydroxide flocs formed under carefully controlled conditions. Two different methods are used for measuring floc dimensions and their distribution. From the experimental results other floc characteristics such as floc strength and size of the flocculi are deduced. Also the reaction constant, the destabilization factor and the growing constant of the coagulation and flocculation process are calculated. Using the influence of rapid mixing time on all floc characteristics and kinetic parameters minimum and maximum limits for the rapid mixing time are deduced.
Biochemical Aspects of Enhanced Biological Phosphorus Removal from Wastewater
Authors: Hascoet M. C. , Florentz M. , Granger P.
Published: May 2018

Enhanced biological phosphorus removal from wastewater by means of microorganisms found in activated sludge has for the past few years been the subject of much research and it is now commonly recognized that an activated sludge system must include alternating anaerobic-aerobic periods.

The present article covers biochemical aspects of this phenomenon using a phosphorus removing biomass obtained in a laboratory-scale pilot with alternating phases and a synthetic substrate feed. The percentage of phosphorus obtained in the pilot sludge was four times greater than that of a conventional sludge plant.

By exposing the same biomass to different conditions and using 31P Nuclear Magnetic Resonance, we were able to accurately pin-point the various forms of phosphorus found within cells and follow their development during the course of alternating phases. The following results were obtained:the transformation of phosphorus in its inorganic to polyphosphate form depends on the medium's level of oxygenation,the presence of nitrates disturbs the anaerobic period but does not affect phosphorus uptake in the aerated period.Continuous nitrate addition alters biomass behaviour in the anaerobic phase, which loses the capacity to release phosphorus,copper at a concentration of over 1 mg Cu2+/1 inhibits phosphorus uptake in the aerated phase.

Various microbiological analyses made on the pilot biomass isolated conventional bacteria found in activated sludge.
An Aut-Ecological Study of Acinetobacter in Activated Sludge
Authors: Cloete T. E. , Steyn P. L. , Buchan L.
Published: May 2018

Data are reported on the role of Acinetobacter in phosphate removal in activated sludge. The fluorescent antibody (FA) technique was applied in an autecological study of Acinetobacter in this habitat.

Results indicated that Acinetobacter was present in numbers exceeding 106 organisms per cm3 throughout all zones of the activated sludge process, with higher numbers occurring in the aeration zone. It was also found that Acinetobacter numbers did not vary regardless of whether phosphate was removed or not. Combined electron microscopy and electron dispersive micro-analysis of X-rays (EDAX) furthermore indicated that bacteria from phosphate removing activated sludge plants contained phosphate granules, whereas those from non-removing plants or where removal had stopped, did not contain phosphate granules at all.

Hence, it was concluded that no major population shifts of Acinetobacter occurred in activated sludge and that the process of phosphate accumulation is induced in Acinetobacter. However, Acinetobacter never occurred in numbers sufficiently large to account for phosphate removal to the extent sometimes observed in activated sludge.
Phosphorus Removal at Low Sludge Loadings
Authors: Rensink J. H. , Donker H J. G. W. , Simons T S. J.
Published: May 2018

Pilot plant studies for phosphorus removal with settled domestic waste water at low loadings resulted in 40–50 % P-removal. Addition of 100 mg acetic-acid-COD per liter waste water at low sludge loadings showed a P-removal of more than 97,5 %, even at long periods of rainfall. Instead of dosing acetic acid, experiments were carried out by prolongation of the sludge retention time in the anaerobic zone to promote production of low fatty acids. Half an hour stirring followed by three hours non-stirring of the anaerobic zone improved the P-uptake to 79 %. Seeing that the last-mentioned method did not lead to P-effluent values of less than 1 mg/1 biological P-removal experiments were carried out supported by partly P-stripping of the sludge. The P-effluent content dropped to a constant value of 0,4 mg P/l or more than 97,5 % P-removal. Also during long periods of rainfall the P-effluent value remained 0,4 mg P/l. The investigation is in full progress and focused on studying parameters to shorten the sludge retention time in the stripper tank.
Heavy Metal Removal in the Presence of Colloid-Stabilizing Organic Material and Complexing Agents
Authors: Licskó I. , Takács I.
Published: May 2018

It has been established in laboratory model experiments that the removal of dissolved heavyimetals from wastewaters is rendered more difficult in the presence of colloid-stabilizing agents. This unfavourable effect can be eliminated by the addition of Mg2+ ions and the adjustment to a fairly high pH. By increasing the concentration of Mg2+ ions, the pH necessary for destroying the stability of colloidal dispersion can be lowered. These findings also apply to the combined removal of different heavy metals (Cu, Zn, Cr(III), Ni, Cd). In alkaline conditions, in the presence of ammonium salts, some heavy metals (Cu, Zn, Ni) form high stability amine complexes. A higher pH is necessary for the breakdown of these complexes and the satisfactory removal of heavy metals.
Concentration of Impurities during Melting of Snow Made from Secondary Sewage Effluent
Authors: Zapf-Gilje R. , Russell S. O. , Mavinic D. S.
Published: May 2018

When snow is made from sewage effluent, the impurities become concentrated in the early melt leaving the later runoff relatively pure. This could provide a low cost method of separating nutrients from secondary sewage effluent. Laboratory experiments showed that the degree of concentration was largely independent of the number of melt freeze cycles or initial concentration of impurity in the snow. The first 20% of melt removed with it 65% of the phosphorus and 90% of the nitrogen from snow made from sewage effluent; and over 90% of potassium chloride from snow made from potassium chloride solution. Field experiments with a salt solution confirmed the laboratory results.
Ultrapure Water in the Electronics Industry
Authors: Bunnik H. M.
Published: May 2018

The production of integrated circuits needs an ultra pure water to prepare the acid cleaning and etching baths, to clean the matrices in order to stop the acidic action and to fill the cascade or overflow rinse tanks to remove the last traces of processing solutions. Etch, clean, flush and rinse steps are repeated many times for each matrix until the integrated circuit chip is ready. Impurities in the water can cause failures in the integrated circuit. The objective of this paper is to give an idea about the requirements for the ultra pure water used for the above mentioned applications and to describe an installation designed to meet these requirements.
Experimental Evaluation of Modelling Alternatives and Process Parameters for the Single-Sludge Nitrogen Removal System
Authors: Argaman Y. , Brenner A.
Published: May 2018

Experiments were carrried out on bench-scale activated sludge units operated continuously in the single-sludge mode. A synthetic feed consisting of glucose, acetate, ammonium chloride and essential elements was used. The results served to examine the validity of various expressions for process modelling, and to derive several process parameters. For effluent ammonia of approximately 0.5 mg 1−1 a specific nitrification rate of 0.75·gNH+4-N·gVSS−1 day−1 was selected. The maximum nitrification rite was above 1.9 gNH+4-N·gVSS−1 day−1 and the maximum denitrification rate was 1.7 gNO−3N·gVSS −1day−1. The yield and decay coefficients were determined as 0.31 gVSS·gCOD−1 and 0.018 day−1 respectively, for the heterotrophs, and 0.246 gVSS·gNH+4-N−1 and 0.007 day−1 , respectively, for the autotrophs. Microbial counts were in qualitative agreement with predicted values.
Recent Developments in the Treatment of Oily Effluents
Authors: Roques H. , Aurelle Y.
Published: May 2018

After reviewing the nature and importance of the environmental problems caused by oil spilled on seawater, several treatment possibilities have been listed based on STOKES Law.

The results recently obtained in three of these directions are discussed:-the increase of the drop-size (coalescence)-the increase in the differential density (flotation)-the use of a preferential wettability of some materials for recovering the' surface oil film.

In most cases, process efficiency of oil separation is the product of a collision probability between the oil drop and another drop (or bubble) and a collision efficiency characteristic of this kind of interaction.
The Control of Pollution from River Discharges in the Mediterranean
Authors: Mancy Khalil H.
Published: May 2018

The pollution burden of river discharges in the Mediterranean far exceeds all other sources, e.g. land based sources. The main contributors are the Rhone, Po and Ebro. Contributions from the River Nile are expected to be much less than those from rivers in the European continent.

Recent Nile management schemes and irrigation projects in Egypt are posing direct impacts on the Mediterranean. This includes the erosion of the Nile Delta and off-shore pollution due to wastewater discharges. In view of the prevailing circulation patterns in the Mediterranean, these impacts are dominant in the South Levantin region.

Cutrent practices of river management do not necessarily include the protection of marine resources. Similarly, sea protection programs do not include pollution from sources in the river basin. Marine management programs are largely concerned with pollution loads at the points of river discharge.

In the case of a land-locked sea, such as the Mediterranean, it is particularly important to integrate river basin management schemes in the sea protection program. Under a suitable management plan, it could be possible to determine main sources of sea pollution within the river basin. This should serve as the basis for the implementation of control measures, since the problem is not exclusively within the river basin.
Enteric Virus Removal from Water by Coal-Based Sorbents: Development of Low-Cost Water Filters
Authors: Chaudhuri Malay , Sattar Syed A.
Published: May 2018

Using poliovirus type 1 (Sabin) and dechlorinated tap water, several coal-based sorbents were tested for their capacity to remove viruses from water. The sorbents included bituminous coal from Giridih, India, pretreated/impregnated with either alum, ferric hydroxide, lime or manganese dioxide. Filtrasorb-400, commercially available active carbon, was used as a reference. In batch tests, with input virus concentration of 2.34-2.83×106 PFU l−1 and sorbent concentration of 10 g l−1, alum pretreated coal removed about 96% of the virus when pH of the water was between 6.3 and 8.9. Virus sorption was rapid and a plateau was reached in 30 min. Compared with the active carbon, alum pretreated coal exhibited greater sorption energy and about one log higher limiting poliovirus sorption capacity. Downflow column study indicated the potential of alum pretreated coal as a filter media for removing enteric viruses from water. A previous study showed this sorbent to be capable of removing enteric bacteria as well. Water filters prepared from such low-cost material may prove useful for domestic use in rural areas of India and other developing countries.
Disinfection of Chlorine Resistent Enteroviruses in Ground Water by Ultraviolet Irradiation
Authors: Slade J. S. , Harris N. R. , Chisholm R. G.
Published: May 2018

Human enteroviruses, predominantly poliovirus type 1, occurring naturally in chalk well water, have been found to survive disinfection consisting of a nominal 1.0 mg/1 of free residual chlorine maintained for a minimum contact time of 15 minutes at a pH value of 7.2 and a temperature of 11°C. Disinfection with 1.5 mg/1 of chlorine under the same conditions resulted in virus inactivation and they were also destroyed by exposure to 25 mJ/cm2 of ultraviolet light. It is considered that the apparent chlorine resistance of these viruses is due to their association with an organic floc rather than to any innate property of the virus or of the water. The implications of these results for the treatment of this water are discussed.
The Recovery of Enteric Viruses and Coliphages from Shellfish
Authors: Brodisch K E. U. , Idema G. K. , Coubrough P. , Grabow W O. K.
Published: May 2018

Shellfish meat was seeded with polio and reoviruses, the SA11 simian rotavirus and two coliphages, VI and MS2, in order to study methods of virus recovery. An adsorption-elution-flocculation procedure had an efficiency of recovery of about 66% for poliovirus, but only 3% for reovirus, 1% for SA11 virus and 2% for the two coliphages. The poor efficiency of recovery of all viruses except poliovirus, may be due to inactivation by exposure to low and high pH levels which form part of the recovery procedure. In another procedure seeded shellfish meat was simply homogenized in distilled water and centrifuged. The supernatant was decontaminated with chloroform and directly analyzed. The efficiency of recovery of this procedure was only about 8% for poliovirus, but 44% for MS2 and 50% for VI phages. Chloroform treatment had an adverse effect on the phages, because the elimination of this step increased the efficiency of recovery to 50% for MS2 and 62% for VI. These results indicate that the phages do not adsorb tightly to the shellfish meat and can, therefore, readily be recovered. Enteric viruses, on the other hand, adsorb tightly to shellfish meat and special procedures are required to accomplish meaningful recovery. These findings suggest that different procedures should be used for the recovery of various viruses from shellfish meat.
An Epidemiological Model of the Potential Health Risk Associated with Various Pathogens in Wastewater Irrigation
Authors: Shuval H. I. , Yekutiel P. , Fattal B.
Published: May 2018

The primary goal of this study has been to carry out a rigorous, critical review and evaluation of all available documented epidemiological evidence with the aim of determining the significant, quantifiable, health effects on population groups directly or indirectly exposed to wastewater irrigation: through occupation; by residing in continguous communities or by consuming the sewage irrigated crops. Based on these findings, we have developed an epidemiological model predicting the degree of risk associated with various groups of pathogens.

Based on theoretical consideration of the model and confirmation by the empirical evidence collected and analyzed in this study, we have concluded that the risk of pathogen transmission by irrigation with raw wastewater for most developing countries is according to the following descending order: high - helminths (Ascaris, Trichuris, Ankalostoma and Taenia), lower - bacteria (Typhoid and Cholera); and lowest - viruses.

In general, it can be stated that based on both the theoretical and empirical findings of this study, there appears to be a basis for relaxing the conventional effluent quality standards for unrestricted crop irrigation. A guideline of no helmiths in 1 liter and a log mean of 1000 fecal coliforms/100 ml is proposed.
Waste Disposal in the Sea off Southern California
Authors: Bascom Willard
Published: May 2018

Southern California, with a coastal population of 12 million people, releases about 4.4 million cubic meters of treated waste water into the Pacific every day via outfalls that discharge three to six kilometers offshore at a depth of 60 meters. Diffusers cause each liter of waste to be diluted by 150 liters of deep cool water preventing it from reaching the surface except for short periods in winter. Data on the constituents of the four largest waste streams are presented and a brief account of the research done by the Southern California Coastal Water Research Project is given. Although the waste water now discharged meets rigorous state standards (with minor exceptions) and the steady improvement in sea conditions over a decade has been well documented, there is a continuing debate over whether our coastal waters are adequately protected. This is primarily because the damaging effects of DDT and PCBs that were discharged more than 14 years ago have been slow to go away. Although the amounts of DDT and PCB in sea animals are only one- tenth what they were a decade ago they tend to obscure the value of the improvements and the present discharge practices. The alternatives to sea disposal seem likely to cause greater damage to the overall environment.
Initial Dilution Prediction for Ocean Outfalls
Authors: Roberts Philip J. W.
Published: May 2018

Methods for predicting initial dilution and rise height of wastefields produced by ocean outfalls are reviewed. Equations are presented for estimating these parameters for limiting cases dependent on whether the jets are merging or non-merging, and on whether the receiving water is stagnant or flowing, density stratified or uniformly mixed.
Granulation in UASB Reactors
Authors: Dolfing J.
Published: May 2018

The state of knowledge on the microbiological aspects of granular methanogenic sludge in upflow anaerobic sludge blanket (UASB) reactors is reviewed. Granular methanogenic sludge has been observed in a variety of upflow reactors, which is in agreement with the hypothesis that these systems select for well settling sludges. In methanogenic UASB reactors various types of well settling sludges have been observed. Microscopic and kinetic evidence suggests that acetoclastic Methanothrix-like organisms play an important role in determining which type of sludge will develop under methanogenic conditions. The mechanism of granulation still remains obscure. Extracellular material indoubtedly plays a major role as a matrix which keeps the cells together. Scanning electron microscopic evidence for the presence of extracellular material is available, but transmission electron microscopy has failed to validate the hypothesis that exopolysaccharides are the dominant components in this matrix.
New Technologies for Anaerobic Wastewater Treatment
Authors: Pol Look Hulshoff , Lettinga Gatze
Published: May 2018

Presently anaerobic wastewater treatment is becoming an accepted simple technology for the treatment of a variety of wastewaters. Of the different treatment systems that have been developed the UASB process (Upflow Anaerobic Sludge Blanket) has found the widest application. Almost all of the more than 60 full scale UASB reactors in operation now, are running satisfactorily. The excellent sludge retention generally found in UASB-reactors is obtained by sludge granulation, which can be seen as a sludge immobilization process. The presently available insight into the sludge granulation process is briefly presented, together with the strategy to be applied for performing a proper first start-up and secondary start-up of UASB reactors, viz. using granular seed sludge. The effect of the presence of SS with regard to the loading potentials of anaerobic treatment systems will be discussed. The experiences obtained with some full scale applications of the UASB-process are presented.
Anaerobic Upflow Bed-Filter – Development and Application
Authors: Kennedy K. J. , Guiot S. R.
Published: May 2018

The Upflow Sludge Bed-Filter (UBF) design provides high active biomass concentrations and long solid retention times (SRT) allowing the treatment of dilute to high strength wastes at high organic loading rates (LR) and short hydraulic retention times (HRT). The UBF system was shown to withstand severe organic shock loads and recover within a reasonable period of time. The effect of packing material on biomass retention and biomass characteristics and reactor performance was determined. A pseudo-steady state (PSS) model was developed that predicts reactor performance as a function of HRT or biomass concentration. Application of this model to step-up and step-down experiments indicated that two sets of kinetic parameters were required to account for hysteresis effects. Application of the UBF concept to the treatment of municipal landfill leachate resulted in greater than 95% COD removal at LR upto 33 kg COD/m3.d.
Development, Testing and Intercalibration of Reference Methods for Pollution Studies in Coastal and Estuarine Waters
Authors: Aston S. R.
Published: May 2018

Following the 1972 United Nations Conference on the Human Environment, the United Nations Environment Programme (UNEP) initiated a Regional Seas Programme in 1974. At present the Programme involves ten regions and has over 120 coastal states participating.

It is conceived as an action-orientated programme having concern not only for the consequences but also for the causes of environmental degradation and encompassing a comprehensive approach to combating environmental problems through the management of marine and coastal areas. Each regional action plan is formulated according to the needs of the region as perceived by the governments concerned. The overall strategy of the programmes was defined by UNEP's Governing Council as:Promotion of international and regional conventions, guidelines and actions for the control of marine pollution and for the protection of management of aquatic resources.Assessment of the state of marine pollution, of the sources and trends of this pollution, and of impact of the pollution on human health, marine ecosystems, and amenities.Co-ordination of the efforts with regard to the environmental aspects of the protection, development and management of marine and coastal resources.Support for education and training efforts to make possible the full participation of developing countries in the protection, development and management of marine and coastal resources.

One of the basic components of the regional action plans is the assessment of the state of marine pollution. For this purpose a set of Reference Methods for marine pollution studies is being developed. The paper describes the development of Reference Methods for use by participants in Regional Seas Programmes, where they are intended to ensure that the data can be compared on the world-wide basis and thus contribute to the Global Environment Monitoring System (GEMS) of UNEP. Also, the basis for the Reference Methods as a basis by which countries can adopt comparable methods of assessing the extent of marine pollution in the event of inter-governmental disputes is explained.

The Reference Methods being developed cover a wide range of pollutants, e.g. trace metals, chlorinated hydrocarbons, petroleum hydrocarbons, tar, bacteria, etc., as well as providing guidelines for sampling strategies, preparation of samples, toxicity tests, data handling and evaluation. In addition, they include information on how basic oceanographic parameters are to be assessed and used to supplement the data on marine pollution.

The paper draws on particular aspects of the development and testing of some individual Reference Methods to illustrate the problems and philosophy adopted for a project which represents a world-wide attempt to promote the detection, understanding and control of coastal and estuarine pollution. The scientific criteria for method selection and application emphasize the pragmatic approaches which are being adopted to fulfil this ambitious project.
Monitoring Effects of Catchment Management Practices on Phosphorus Loads into the Eutrophic Peel-Harvey Estuary, Western Australia
Authors: Birch P. B. , Forbes G. G. , Schofield N. J.
Published: May 2018

Early results from monitoring runoff suggest that the programme to reduce application of superphosphate to farmlands in surrounding catchments has been successful in reducing input of phosphorus to the eutrophic Peel-Harvey estuary. In the estuary this phosphorus fertilizes algae which grow in abundance and accumulate and pollute once clean beaches.

The success of the programme has been judged from application of an empirical statistical model, which was derived from 6 years of data from the Harvey Estuary catchment prior to a major change in fertilizer practices in 1984. The model relates concentration of phosphorus with rate of flow and time of year. High phosphorus concentrations were associated with high flow rates and with flows early in the high runoff season (May-July). The model predicted that the distribution of flows in 1984 should have resulted in a flow-weighted concentration of phosphorus near the long-term average; the observed concentration was 25% below the long-term average. This means that the amount of phosphorus discharged into the Harvey Estuary could have been about 2 5% less than expected from the volume of runoff which occurred. However several more years of data are required to confirm this trend.
Mercury Contamination in Components of an Estuarine Ecosystem
Authors: Elliott M. , Griffiths A. H.
Published: May 2018

Tne Forth Estuary, Scotland, has received a discharge containing mercury for several decades. This study describes the ecological effects of that discharge as contamination in many components of the ecosystem and attempts to quantify the standing mass of Hg within those components. The contaminated area is contrasted with a less-contaminated area, 19km downstream, and shown to have significantly greater Hg levels in most components (sediments, plankton, infauna, epi-fauna, macroalgae and fish). The standing mass of Hg in the biota is 1% of that in the non-biotic components (sediments, suspended material and soluble phase); sediments alone contain 97% of that standing mass. The critical pathways in this system are (i) the sediment-infauna-estuarine demersal fish and wading birds, and (ii) suspended material-mussels-oystercatchers. Therefore, the top consumers in each of these are most at risk from increased contamination. However, in assessing the biological effects of increased contamination, there was no change at the contaminated area in fecundity in the viviparous estuarine demersal fish, Zoarces viviparus.
Molecular and Cellular Indices of Pollutant Effects and Their Use in Environmental Impact Assessment
Authors: Moore Michael N. , Lowe David M. , Livingstone David R. , Dixon David R.
Published: May 2018

Marine and estuarine environments receive a wide variety of contaminant chemical (xenobiotic) inputs, which must now be regarded as constituents of the natural system; these xenobiotics tend to over-load the normal physiological mechanisms for their disposal. The credit for the continued survival of organisms must be accorded to the protective mechanisms of biotransfor-mation or detoxication present in cells. These include the NADPH-dependent cytochrome P-450 monooxygenases, which metabolize toxic organic xenobiotics, metallothioneins which bind and detoxify many metals and lysosomal accumulation which sequesters many xenobiotics thus compartmentalizing them away from other cellular components.

This presentation considers the development of early-warning systems based on biological responses to cell injury at the molecular, subcellular and cellular levels of organization, with particular emphasis on the use of marine mussels and periwinkles as sentinel organisms for assessing pollutant effects. Responses discussed include those of the microsomal detoxication system to organic xenobiotics, functional and structural responses of lysosomes to organic and inorganic xenobiotics, quantitative structural alterations in the cells of the digestive and reproductive systems and finally genotoxicity measured using aneuploidy and sister chromatid exchange as indices of chromosomal damage. Where possible these indices are discussed in an integrated manner.
Sanitation Program Development for Rural Thailand in Relation to the International Drinking Water Supply and Sanitation Decade
Authors: Muttamara S. , P Ricarte H.
Published: May 2018

The sanitation level in the villages of Thailand is still generally low despite the past efforts of the Sanitation Division of the Department of Health. Consequently, the Royal Thai Government (RTG) is embarking on a national sanitation program with a view to minimizing the occurrence of excreta-related diseases in the rural communities, which will be implemented together with the rural water supply program, so as to produce the optimum effects on health. This dual program, otherwise known as the “Thailand Decade Plan,” will be initiated in 1985 and will continue until the end of 1991. The realization of this plan will serve as Thailand's commitment to the International Drinking Water Supply and Sanitation Decade (IDWSSD).

With only 2.8 million pour-flush (PF) latrines installed up to the end of 1983, accounting for 44.3% of the total number of households, the plan calls for the provision of an additional 2.5 million PF latrines in order to achieve the target, which is to provide 75% of households with PF latrines by the end of 1991. Considering the attitudes and economic status of the Thai rural people, the proposed strategies for the implementation of the sanitation program will be the provision of material subsidies and/or “revolving funds,” with strong support from such activities as health education, especially for women and children, and the necessary training of personnel. Implementation of the plan will require an investment of approximately Baht 1,792.6 million (roughly U.S.$ 66.4 million).
International Co-Operation for the Improvement of Environmental Sanitation by Japan
Authors: Unno H. , Yamamura S.
Published: May 2018

Japan has made remarkable progress in water supply and sanitation during the past 100 years. On the other hand, many developing countries lack adequate water supply and sanitation facilities, which causes high mortality rates. The “International Drinking Water Supply and Sanitation Decade” (IDWSSD) has been promulgated by the UN since 1981 to cope with this problem. Japan has made efforts to develop foreign assistance projects in the water supply and sanitation field since 1968. Recently, after the promulgation of IDWSSD, such activities have been expanded. However, there exist many problems in Japanese economic and technical assistance partly because Japan has rather less experience in foreign assistance than other advanced countries. Therefore effective measures should be taken to conduct more appropriate foreign aid programmes.
Experiment on Municipal Wastewater Treatment in Bangkok, Thailand
Authors: Sumiyama J. , Matsushita J. , Suwanarat K.
Published: May 2018

Due to explosive urbanization in Bangkok, it was realized that it would be difficult to adapt the conventional sewerage system to cope with the increased load. It was more feasible to collect wastewater by the existing drains and to adopt a modified aeration method for treatment of typical municipal wastewater, namely effluent from on-site septic tanks. An experimental test plant was constructed to evaluate the treatability of municipal wastewater generated from the major drainage area, in comparison with that of conventional wastewater from a new community with a separate sewer system. The results verified the higher treatability of the municipal wastewater compared to the communal wastewater with respect to effluent water quality, settleability of mixed liquor, solids production, etc.
Sanitation and Utilization of Night Soil in Rural Areas
Authors: Shin K. C.
Published: May 2018

In the past the concentration of population in the big cities of Korea led to the neglect of the interests of the rural population. Of late even though living conditions have become visibly better, sanitary conditions have not been attended to and consequently have remained bad. In the course of a research programme, which took place between German and Korean institutes, not only the utilisation and treatment of nightsoil, but also model types of toilets, suitable for Korea, were examined. Based on the results of investigations of 4 different types of toilets, a new type (KISTLET) was developed, especially for rural areas with limited water supply and without sewage systems.

Up to 1975 about 29 000 simple biogas plants had been set up in Korea. In order to avoid the disadvantages of small plants a central plant with a digester capacity of 100 m was built. 19% of the gas produced was used for heating the digester, and warm water was prepared using solar energy. This plant was followed by a larger plant with a digester volume of 600 m. A rural household could save 32% of its energy expenses by using biogas.
The Pollutant Load Factor of Household Wastewater in Japan
Authors: Ukita Masao , Nakanishi Hiroshi , Sekine Masahiko
Published: May 2018

The objective of this study was to clarify quantitatively the role of household wastewater as one of the causes of the rapid pollution of nearby water-bodies and to consider the importance of countermeasures at the stage of pollutant load generation. Using mass balance techniques, actual samples and measurements, or by referring to the literature, reliable values of the pollutant load factor of household wastewater were obtained for both the residential and occupational population and after every type of treatment system. Then, to verify the reliability of these values, the flow-out rate of the pollutant load from small river basins was investigated in fine weather. The results show that the proposed values of the pollutant load factor were appropriate, and cesspool night soil and miscellaneous household wastewater are the main causes of the pollution of nearby waterbodies. The results of several experiments show that awareness regarding pollutant load at the stage of its generation, e.g. in cooking and dining, can greatly reduce the pollutant load.
The Characteristics of Community Wastewater Biological Treatment Processes in Taiwan
Authors: Ouyang C. F. , Wan T. J.
Published: May 2018

This study investigated and compared the treatment characteristics of three different kinds of biological wastewater treatment plants (including rotating biological contactor, trickling filter and oxidation ditch) which are currently operated in Taiwan.

The field investigation of this study concentrated on the following items: the performance of biological oxygen demand (BOD) and suspended solids (SS) removal; the sludge yield rate of BOD removal; the settleability of sludge solids; the properties of sludge thickening; the power consumption and land area requirement per unit volume of wastewater.

Finally, based on the results of the field investigation, a comparison of the treatment characteristics of the three different biological treatment processes was evaluated.
Use of Soil for Disposal of Domestic Sewage
Authors: Yamaura G. , Suzuki T. , Kobayashi M. , Katsuno T. , Ogiwara K. , Taguchi Y.
Published: May 2018

Experiments using soil columns, lysimeters, and a field were conducted by permeation of outflow water from a septic tank. In experiments using soil columns, loam columns of over 25 cm in length gave removal percentages of over 9 0% for BOD, T-P, and coliforms. Lysimeters and a field registered removal percentages around 90% for BOD, T-P, and coliforms, but often below 50% for T-N. The field experiment was continued for 10 years without giving any indication of deterioration of quality of permeant water. A soil analysis in the field experiment revealed that the permeant water diffuses laterally 100 cm relative to the trench within the upper layer, with the diffusion range increasing to more than 300 cm with depths over 250 cm.
Subsurface Injection of Activated Sludge: Response of two Grass Species
Authors: Tedesco M. , Ligo M. , Gianello C. , Simon Z.
Published: May 2018

Excess activated sludge produced at SITEL, the integrated effluent treatment plant of Pólo Petroquímico do Sul (South Petrochemical Complex), Triunfo, Brazil, is disposed of by subsurface injection on pangola grass fields at average rates of 24 tons/year (dry basis). Until now no definite destination has been found for the hay, due to its poor commercial value.

With the purpose of investigating the behavior of more commercially valuable species under sludge application, a growth-leaching pot experiment is being conducted at the Soils Department of UFRGS (Federal University of Rio Grande do Sul). Oats (Avenastrigosa) and rye grass (Loliummultiflorum) were the first species to be tested. Sludge application rates varied from 0 to 6 times the recommended operational values. The following topics were studied to date: (a) uptake of mineral nutrients N, P, K, Ca, Mg, Cu, Zn and S; (b) translocation of heavy metals Cd, Pb and Cr to shoots; (c) leaching of nutrients and metals. Initial results showed that:

(i) Sludge applied at rates up to 24 t/ha (dry basis) did not cause any phytotoxic effect. However, plant macronutrients released by sludge into soil did not reach the quantities required for proper agronomic management of the crops.

(ii) Nitrogen was the growth limiting nutrient and also phosphorus to a lesser extent. Potassium was supplied mainly by the soil.

(iii)Some constituents that appeared in leachate from chemically-treated pots did not leach from sludge-treated pots, showing an environmental benefit from sludge over mineral amendments in that respect.

(iv) Mineral nitrogen, mainly nitrate, was detected in leachate for about 45 days, decreasing with time.

(v) Cu, Zn, Pb, Cd and Cr did not appear in plant tops and leachate from sludge-treated pots in worrysome amounts.

The investigation proceeds with cultivation of pangola grass and millet.
Experiences with Land Treatment of Wastewater in the Federal Republic of Germany
Authors: Boll Reiner , Kayser Rolf
Published: May 2018

The largest wastewater land treatment facility in operation in the Federal Republic of Germany is located in Braunschweig (Lower Saxony) and serves a population of about 290,000. The 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 180 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.