bluuebunny/crossref_metadata_2025 huggingface dataset:
German Experiences with Sewage Treatment Ponds
Authors: Bucksteeg K.
Published: May 2018

In Germany there are both highly industrialized regions with large towns as well as extended rural areas with small communities. Most of these communities need regular sewage disposal systems. Sewage treatment plants have to be adapted to special situations in rural villages. Ponds fulfil the requirements in an excellent way. Many hundred of ponds are in operation and three kinds of pond systems are in use:▸facultative ponds (more than 1000 plants) for serving less than about 1000 i+ie*;▸artificially aerated ponds (more than 300 plants) for treating sewage of about 1000 to 10000 i+ie especially when food industries are connected or as an individual solution for those industries;▸ponds combined with trickling filters or rotating bio-filters (more than 100 plants) as a solution for treating preferably domestic sewage from about 1000 to 4000 i+ie.

Lay out, design figures, recommendations for construction and operation, effluent results anc costs are presented on the basis of experiences with numerous plants. Actual effluent results are considerably below German Effluent Quality Standards. Facultative ponds with 10 m2/ie specific surface area produce the following effluent quality: COD ≤ 90 mg/L, BODr ≤ 25 mg/L, NH4≤N = 15 mg/L, PO4-P ≤ 6 mg/L. Heavy algae blooms cause an increase of effluent concentrations: 100 µg Chlorophyll-α represent about 9 mg COD and 3 mg BOD5 on the average.
Waste Stabilization Ponds in France: An Overall Review
Authors: Boutin P. , Vachon A. , Racault Y.
Published: May 2018

In 1983 and 1986, surveys were conducted all over France on wastewater stabilization by “natural” ponds (lagoons), including an almost exhaustive inventory of the 1400 plants then operating. The statistical interpretation of collected data made it possible to analyse the spread of this technique, which became truly popular only ten years ago, and to discern the usual design basis and regional features. With a mean plant area of 5500 m2, lagoons are usually restricted to the treatment of effluents from rural communities, with the exception of large plants in coastal touristic areas. Partially planted ponds are a competing alternative to conventional algal lagooning. Current conditions of pond management are reviewed, with results of effluent quality.
Ammonia Toxicity to Algal Growth in Waste Stabilization Ponds
Authors: Konig A. , Pearson H. W. , Silva S. A.
Published: May 2018

The ammonia concentrations in 1.25 and 2.3 metre deep waste stabilization ponds at Extrabes N.B. Brazil receiving domestic sewage were largely independent of the surface organic loadings on the deep ponds at least above loading rates of 200 kg BOD5 ha−1 d−1, but varied with time between 14 and 29 mg L−1 (NH3-N). During daylight, pH values reached about 9.0 (or sometimes higher) in the surface water layers as a result of algal photosynthesis. Laboratory growth studies showed that a pond isolate of Chlorella was more tolerant to ammonia than the Euglena species and grew in media containing l0mM ammonia at a pH of 9.0 and a temperature of 25°C when 40% of the total ammonia concentration was in the toxic unionised NH3 form. This tolerance would appear to be inherent since the Chlorella was isolated from ponds containing ammonia concentrations at 1 to 2mM and was subsequently maintained routinely in the laboratory at such ammonia levels. The differential sensitivity to ammonia exhibited by pond algae is discussed in terms of waste stabilization pond performance.
Factors Determining Algal Populations in Waste Stabilization Ponds and the Influence of Algae on Pond Performance
Authors: Pearson H. W. , Mara D. D. , Mills S. W. , Smallman D. J.
Published: May 2018

In situ and laboratory experiments were performed on species of the waste stabilization pond algae Chlorella, Scenedesmus, Euglena and Chlamydomonas to investigate the utilization of various organic acids and sugars, light limitation on species dominance and the toxicity of ammonia and sulphide. Euglena showed the most flexible metabolism and was able to utilise butyrate. Scenedesmus did not grow on any of the substrates in the dark. Pond populations of Euglena and Chlamydomonas were able to incorporate acetate in situ in competition with the heterotrophic bacterial population but Chlamydomonas was the more successful. Light availability affected speciation in facultative ponds where rapid motility by flagellates was a clear advantage. All the algal species were sensitive to sulphide at µM concentrations in a tolerance sequence ChlamydomonasChlorellaScenedesmusEuglena. Ammonia was less toxic than sulphide and the tolerance sequence was ChlorellaScenedesmusChlamydomonasEuglena. It was the undissociated forms of both sulphide and ammonia which were toxic, Toxicity was influenced by pH and this would be a critical factor controlling ammonia inhibition of algal photosynthesis in ponds. The effects of these findings are related to species dominance and pond performance.
Physico-Chemical Parameters Influencing Faecal Bacterial Survival in Waste Stabilization Ponds
Authors: Pearson H. W. , Mara D. D. , Mills S. W. , Smallman D. J.
Published: May 2018

In situ studies on waste stabilization ponds (in Portugal) showed that faecal coliform numbers were lowest at positions in the water column where pH, temperature, dissolved oxygen and algae were high. Numbers were not always lowest at the surface where light intensities were highest or in ponds where light penetration had increased through algal grazing by Daphnia. Laboratory studies showed that pH values approaching 9.0 or above increased faecal coliform die-off particularly under nutrient-poor conditions. Elevated temperatures enhanced the pH effect but the level of dissolved oxygen made little difference. Streptococcus, Salmonella and Campylobacter isolates all behaved similarly to the faecal coliforms. Daphnia grazing of the algal population in maturation ponds may reduce the microbial quality of the final effluent. These findings are discussed in relation to pond design.
Reuse of Stabilization Pond Effluent for Citrus reticulata (Orange), Forest and Road Verge Plants
Authors: Kale C. K. , Bal A. S.
Published: May 2018

Utilisation of domestic seuage, treated in a stabilization pond, for growing orange (Citrus reticulata var - Nagpur Orange), forest and verge plants was initiated at the National Environmental Engineering Research Institute, Nagpur in 1978. The irrigation quality of the stabilization pond effluent (SPE) was compared with that of well waters at NEERI and at the orange farms of Katol and warud (35 to 55 km north of Nagpur). The SPE was found to be comparable with these well waters. Soils on NEERI fields uere also found comparable with those of some of the orange farms at Uarud and Katol. Irrigation scheduling was formulated for oranges at NEERI. To study effects of 3PE irrigation, some of the orange plants uere irrigated with well water and ethers with the SPE. Fruiting on most of the plants was not regulated; effluent irrigated plant leaves exhibited similar osmotic concentration but higher succulence than well uater irrigated plant leaves; there was an increase in potassium, decrease in sodium and no effect in calcium content in the uater extracts of SPE irrigated leaves. Amongst the forest and verge plante, Cassia siamia. Peltophoruminerme, Enterelobiumsaman. Casuarinaequisetifolia, Eucalyptuscitrodora,Lagerstroemiaspeciosa, Terminalia catappa and Leucaenaqlauca responded well to SPE irrigation, though the response varied with the soil conditions. A garden developed around pilet seuage treatment plants clearly demonstrates scientific reuse of treated seuage for creating an appealing landscape and beautification of otherwise discarded areas.
Studies on High Altitude Waste Stabilization Ponds in Peru
Authors: Pearson H. W. , Mara D. D. , Thompson W. , Maber S. P.
Published: May 2018

Studies on waste stabilization ponds at Cajamarca (altitude: 2,675 metres) and Juliaca (3,827 metres) in Peru have shown that existing pond design equations can be confidently used for designing ponds for high Andean towns, even though there are large diurnal variations in air temperatures and high light intensities. Some caution must be exercised above 3,500 metres, however, since safety margins are reduced. Sludge accumulation was minimal, despite the pond water temperatures being lower than 15°C in the region of the sediments.
Treatability Studies of Palm Oil Refinery Wastewaters
Authors: Chin K. K. , Ng W. J. , Ma A. N. , Wong K. K.
Published: May 2018

Wastewaters from palm oil refineries were treated using physical-chemical and biological treatment systems. Dissolved air flotation (DAF) af ter chemical coagulation and flocculation with lime, alum, and polyelectrolyte removed more than 90% of the influent COD, suspended solids, and oil and grease. Laboratory data compared closely with pilot and full scale plant operating data. Pretreated wastewaters from physical and chemical refining were further treated with the sequencing batch reactors (SBRs). The SBRs allow the control of reaction time and the maintenance of biological solids to be accomplished in a single tank. Laboratory and pilot scale studies showed a high degree of BOD and COD removal efficiencies. Microprocessor-based timers were used to control the operating modes. The cycle times used varied from 8 to 24 hours. The process showed stability under wide variations of organic strength (300 to 2500 mg/l BOD) and loading rates (0. 4 to 2. 0 mg COD/mg MLVSS).
Wastewater Treatment for Industrial Estates in Southeast Asia Using Water Hyacinths
Authors: Orth Hermann , Lertpocasombut Krittiya , Wilderer Peter A.
Published: May 2018

Pilot scale experiments were conducted to examine the applicability of water hyacinth systems for the treatment of raw wastewater discharged by small factories and housing areas of an industrial estate. Results obtained are encouraging, and justify the idea of starting wastewater treatment in the early phase of an estate's development with aquatic plant treatment systems which later can be further employed for advanced treatment. Although sludge accumulated extensively in the inlet zone of the plug-flow system, and oxygen was deficient in the bulk of the liquid, BOD and COD dropped to a level satisfying secondary treatment standards. Nitrogen was eliminated to a great extent suggesting that nitrification was occurring, presumably at the root surface, and denitrification in the outer oxygen deficient zones. Batch experiments demonstrated that the plants were able to satisfy the oxygen demand of both heterotrophic bacteria and nitrifiers forming the root supported biofilm.
Nitrogen Removal in an Oxidation Ditch with Intermittent Aeration
Authors: Inomae Katsuto , Araki Hiroyuki , Koga Kenichi , Awaya Youichi , Kusuda Tetsuya , Matsuo Yasunari
Published: May 2018

The typical process of nitrogen removal in the oxidation ditch is achieved through the control of oxygen supply ( forming aerobic and anoxic zones within the ditch channel) or alternating aeration using intermittently operating aerator(s). The operating conditions for efficient nitrogen removal with any of these methods have yet to be clarified. The purpose of this study is to establish an oxidation ditch system with a high rate of nitrogen removal by intermittent aeration. Effects of intermittent aeration on nitrogen removal characteristics were studied by experiments with a bench scale- and full scale-plant and by simulation. The conditions of optimum operation (aerobic and anoxic periods) for a high rate of nitrogen removal were found. These conditions principally depend upon the rates of nitrification and denitrification. By operating the full scale plant system with intermittent aeration ( cycle time is 45 minutes and aerobic ratio is 0.42 ), a high rate nitrogen removal efficiency of 81% was achieved without adding any alkaline matter or organic carbon sources. It was shown that the results of simulation agree with the observed data of the full scale plant system, and that the rate of denitrification depends upon the conditions of intermittent aeration.
The Effect of Calcium on Microbial Aggregation during UASB Reactor Start-Up
Authors: Mahoney E. M. , Varangu L. K. , Cairns W. L. , Kosaric N. , Murray R G. E.
Published: May 2018

The dynamics of granule formation were studied using cells from two bench-scale UASB Reactors. The objective was to elucidate factors which influence formation and maintenance of highly active self-agglomerated microbial biomass. Simultaneous examination of biological and physical parameters was performed during the start-up of a calcium-positive (100 mg/1) reactor and a reactor without added calcium. The influence of carbon nutrients and Ca++ on the cell surface and microbial aggregation was studied. The granules formed in both reactors but were larger in the calcium-positive reactor in which they settled 3-4 times faster. A higher rate of biomass accumulation also was evident in the calcium-positive reactor and this allowed a more frequent increase in the substrate loading rate and earlier development of the granular sludge.
Temperature Characteristics of the Methanogenesis Process in Anaerobic Digestion
Authors: Lin C. Y. , Noike T. , Sato K. , Matsumoto J.
Published: May 2018

Experiments using high concentration of the major intermediates of anaerobic digestion were conducted with anaerobic chemostat-type reactors to investigate the temperature characteristics of the methanogenesis process. Temperature ranging from 15°C to 50°C were studied. The optimum temperature was 35°C. The methane production was temperature and loading rate dependent. Bacilli were the predominant microbial species and this predominance was independent of digestion temperature. At the mesophilic range, with increasing temperature the saturation constant (Ks) decreased, while the maximum specific substrate utilization rate (vmax) and growth yield (Yg) increased. Their temperature characteristics were described using exponential expressions. For retention times longer than 8 days, the process progressed normally and satisfactorily even at 25°C, and the substrate removal efficiency was more than 96% which was the same as that at 35°C. At the temperature range of 25°C to 35°C, the simulation model is
Removal of Hazardous Organic Pollutants by Adsorption on Microbial Biomass
Authors: Bell J. P. , Tsezos M.
Published: May 2018

Removal of five toxic organic compounds from water by adsorption on microbial biomass was investigated. Lindane, diazinon, malathion, pentachlorophenol, and the PCB 2-chlorobiphenyl were adsorbed onto two types of inactive microbial biomass (a pure strain of Rhizopusarrhizus, and a mixed culture of activated sludge). Desorption and the thermodynamics of the adsorption process were also investigated. With the exception of malathion, the adsorptive uptake data fit the Freundlich equation and were well correlated with the octanol/water partition coefficient, but not as well correlated with water solubility of the compounds. Except for malathion the adsorption was reversible. Malathion showed unusually high apparent uptake and the removal appeared to be irreversible. The experimental evidence suggests that the disappearance of malathion resulted from a chemical reaction, while physical adsorption appears to account for removal of the other compounds.
Biological Decomposition of Trace Organic Compounds
Authors: Shibata M. , Nakamura K. , Miyaji Y.
Published: May 2018

Biological decomposition of trace organic compounds was investigated to apply to the reclamation system of the rinse water recovered from semiconductor manufacturing processes. First, growth characteristics of microorganisms grown at low concentrations of organics were examined and extremely low saturation constants for acetate and methanol were obtained. Based on the growth characteristics, a biological fluidized bed reactor was operated to remove low concentrations of organics in a laboratory scale. One milligram per liter of acetate carbon was degraded to less than 10µg/l carbon with 10 minutes of hydraulic retention time. Low concentrations of methanol and isopropanol, which are main organics contained in the recovered rinse water, were also decomposed effectively. For a full scale operation, a pilot study was also carried out to examine treatability and stability of a fluidized bed reactor. Effluent organic concentrations decreased gradually and had been stable below 5µg/l carbon during 5 month operation.
Performance Evaluation of Rotating Biological Contactor Process
Authors: Tanaka K. , Oshima A. , Rittmann B. E.
Published: May 2018

Rotating Biological Contactors (RBC) have only recently been introduced in Japan as a means of providing secondary treatment to domestic wastewaters. The use of RBCs appears to be particularly attractive for small communities because of their low energy demand and reduced O-M requirements. To evaluate and demonstrate the feasibility of the process as an alternative to conventional secondary treatment, a field study was performed at three municipal facilities in Japan. A single, fundamental model of biofilm kinetics was shown to be capable of accurately predicting soluble BOD5 removals throughout the RBC. Model and field study results indicated that effluent soluble BOD5 should be 3 to 7 mg/l for conventional loads. Approximately 30 percent of the RBC effluent solids were found to be fine particles having a settling velocity of less than 10 to 15 m/day and which exerted 60 to 70 percent of the final effluent total BOD5. Therefore, special attention must he given to solids-liquid separation of the RBC effluent to ensure that the final effluent is of acceptable quality. Several solids-liquid separation methods, including direct screening of RBC effluent, were shown to be feasible in upgrading the effluent quality.
Molecular Weight Distributions of Soluble Organic Matter in Various Secondary and Tertiary Effluents
Authors: Amy Gary L. , Bryant Curtis W. , Belyani Mosen
Published: May 2018

Differences in the nature of soluble organic matter were measured for various full-scale wastewater treatment processes. Conventional activated sludge, pure oxygen activated sludge, biofiltration, granular activated carbon, and tertiary sand filtration were evaluated. Effluent soluble organic matter was analyzed by ultrafiltration for the apparent molecular weight distribution of soluble organic carbon and UV-absorbing material. The effects of annual season, secondary treatment process, and tertiary treatment process upon the properties of the effluent soluble organic matter were statistically significant at the 99% level. Effluent properties from the various treatments were sufficiently different to support the concept of the selection of appropriate treatments to minimize the effluent concentration of specific fractions of the soluble organic material as required for specific water reuse applications.
Reduction of Microbial Indicators and Viruses in a Cypress Strand
Authors: Scheuerman P. R. , Farrah S. R. , Bitton G.
Published: May 2018

The fate of bacterial indicators, bacteriophages and enteroviruses was studied in a forested cypress strand treated with primary effluent from the town of Waldo, Florida. Experimental corridors (40m × 10m) were installed in a strand and were treated with pumped primary effluent. Bacterial indicators (total and fecal coliforms, fecal streptococci), bacteriophages and enteroviruses, were removed following 40m travel of sewage through the corridors. The results indicated that fecal streptococci accumulate in the sediments.

The levels of bacterial indicators, phages and enteroviruses were monitored in another strand that had been receiving sewage for 50 years. Microbial numbers were determined at stations situated at increasing distances from the sewage outfall (up to 230m). It was observed that the bacterial indicators were reduced approximately by 3 log10 units at the 230m-station. Fecal streptococci were shown to accumulate in the sediments. The reduction in the number of phages was less and was approximately one log10 unit. Enteroviruses and Salmonella spp. were detected in the cypress strand water. They were often undetectable in the sediments.

The results demonstrate the potential use of wetlands for low-energy treatment of sewage effluents.
Disinfection Efficiency and Problems Associated with Maturation Ponds
Authors: Macdonald R. J. , Ernst A.
Published: May 2018

Reductions in densities of indicator organisms and pathogens were measured in maturation ponds receiving secondary effluents from trickling filter and activated sludge treatment works. Effluent detention times in the ponds were determined using dye tracing techniques and compared with nominal detention times calculated from pond volumes and effluent flow rates. Median detention times were substantially less than nominal times because of short circuiting due to pond design aspects and thermal stratification. Maturation ponds of 10 days median detention time were found to successfully disinfect a poor quality trickling filter effluent and were effective at removing parasite ova and reducing virus densities. Continued use of maturation ponds should be encouraged in developed and developing countries as they have low cost, operational, maintenance and skilled operator requirements and are an effective disinfection process. Pond designs should minimize short circuiting and thus the areal requirements of the ponds.
Oxidation-Reduction Potential (ORP) Regulation: A Way to Optimize Pollution Removal and Energy Savings in the Low Load Activated Sludge Process
Authors: Charpentier J. , Florentz M. , David G.
Published: May 2018

Aeration represents the main part of energy consumption in the low-load activated sludge process. Because of its ability to remove the various kinds of pollution (carbonaceous, nitrogenous) with a high dependability level, this process is the most widespread throughout France, particularly in its tropical overseas regions. A previous study led the authors to set up a graph which links energy savings and effluent quality (carbonaceous and nitrogenous pollution removal). This graph appears useful as well to monitor biological phosphorus removal in the low-load activated sludge process including an anaerobic basin.

In order to optimize pollution removal and energy savings, ORP regulation has been carried out since January 1983 on the Yffiniac plant (West of France). It was preferred to dissolved oxygen (D.O.) regulation because of the low values of D.O. observed in this plant and the difficulties of operating D.O. regulation.

A laboratory and full-scale study shows that ORP regulation is possible and particularly accurate as a contribution to optimizing pollution removal, energy savings and operating conditions. Since then other ORP Regulations have been installed. The observations we made specify which cases lend themselves to successful ORP regulation.
Modeling of Biological Processes in the Subsurface
Authors: Bouwer Edward J. , Cobb Gordon D.
Published: May 2018

Biofilm processes are potentially important for transformations of organic micropollutants in groundwater. The type of electron acceptor used by the microorganisms is an important environmental factor affecting biotransformation. A fundamental model of biofilm kinetics is shown to be capable of simulating microbially-mediated changes in a subsurface system of primary substrates and mixed electron acceptors. The model incorporates external mass transport effects, Monod kinetics with determination of limiting electron donor or acceptor, and competitive and sequential microbial reactions. The system to which the model is applied includes aerobic carbonaceous oxidation, nitrification, denitrification, sulfate respiration, and methanogenesis. The model establishes the dominant electron acceptor condition in a given region so that favorable environments for organic contaminant biotransformation can be determined. Model simulations could suggest useful strategies to achieve aquifer clean-up with biological processes.
Kinetics of Cadium and Copper Hydrolysis
Authors: Patterson J. W. , Haas C. N. , Vamos R. J. , Cooney E.
Published: May 2018

Prior investigators have implicated kinetic limitations as being significant in the regulation of metal removal by precipitation processes. However, there have been no prior direct measurements on rates of such processes with the environmentally more significant metals. This study measured homogeneous complexation rates of cadmium and copper with hydroxide in a complete mix continuous flow reactor, using ion specific electrodes. The cadmium complexation kinetics are consistent with a forward mixed second order process coupled with a reverse first order process, and such model provides agreement with reported equilibrium constants for the formation of CdOH+.
Partitioning of Organic Chlorine between Bulk Water and Benthal Interstitial Water through a Kraft Mill Aerated Lagoon
Authors: Bryant C. W. , Amy G. L. , Neill R. , Ahmad S.
Published: May 2018

This paper reports the measured distribution of total and low molecular weight organic chlorine through a Kraft Hill aerated lagoon. Both benthal interstitial water and corresponding overlying water patterns were measured. Benthal solids were also analyzed for extractable organic chlorine. The extent of organic chlorine partitioning between the overlying water and benthal zone is indicative of the role of biosorption in the transport of organic chlorine compounds from the water column to the sediments and benthal zone of the lagoon. Evidence is presented for the occurrence of microbial dehalogenation within the anoxic benthal deposit.
On Site High Rate UASB Anaerobic Demonstration Plant Treatment of NSSC Wastewater
Authors: Habets L. H. A. , Tielbaard M. H. , Ferguson A. M. D. , Prong C. F. , Chmelauskas A. J.
Published: May 2018

Results of a 19 m3 demonstration plant studies are summarized.

The plant is located at Sturgeon Falls at a NSSC mill and hardboard plant owned by MacMillan Bloedel. The mill discharges 6300 m3/day of waste effluent containing 50 tonnes of BOD and 127 tonnes of COD.

Lab scale testing (1983) and an 18 month 1.4 m3 reactor volume pilot plant study (1985) were completed confirming treatability of the wastewater and suitability of the Upflow Anaerobic Sludge Blanket (UASB) technology among others to successfully treat the mill wastewater. Discharged effluent contains spent sulphite liquor and primary clarifier effluent. As required, the 1.4 m3 Biopaq System successfully achieved BOD reductions in excess of 75 percent at loadings greater than 10 kg COD/m3.d.

As a consequence of this and because of economic considerations, the Biopaq System of Paques-Lavalin was selected for on site demonstration during a 12 months period. This period started in spring 1986. Erection of a full-scale plant is planned to take place in 1988.

The purpose of the on site demonstration study is to confirm wastewater treatability, optimize design loading rates and confirm granular sludge growth. To achieve the objectives and simulate full-scale operating conditions the MacMillan Bloedel pilot plant has been automated and is controlled via a microprocessor incorporating a customized software program. Start-up performance results and operation at incremental loadings under steady state conditions are presented together with the experience gained during extreme variations in mill effluent quality and flow.

Preliminary study results from the first 10 months disclose that a BOD removal efficiency of 80 percent or better is achieved at weekly average loadings of 15 kg COD/m3.d, and the process offers strong resilience to daily swings in wastewater quality. The results also show a net accumulation of granular sludge.

The practical application of this technology from a mill operating perspective is discussed, and the layout for a full-scale installation with projected capital and operating costs is provided.

Most of the contents of this paper was presented at the Tappi 1987 Environmental Conference (Prong etal, 1987). This paper presents the latest results.
The Use of Enzymes for Wastewater Treatment in the Pulp and Paper Industry – A New Possibility
Authors: Hakulinen R.
Published: May 2018

Biological systems have been employed successfully for manv years in the treatment of pulp and paper mill waste water. Previously, not very much was known about enzymes and their possibilities in pulp and paper industry wastewater treatment. There is currently a lot of research activity in the enzymology of lignin degradation. Ligninase, cellulase, peroxidase, etc. are the most important enzymes, especially peroxidase, which is used for color removal in bleaching effluents. It is also possible to mix enzymes together with special microbes, which normally do not have high enzvme activity, and remove recalcitrant and harmless compounds from wastewater. The use of novel enzymes and rDNA technology in sludge and wastewater treatment will also be discussed.
Distribution of Chlorinated Organic Substances from Pulp Mills
Authors: Håkanson L. , Jonsson P. , Jonsson B. , Martinsen K.
Published: May 2018

This is a report from a project sponsored by the National Swedish Environmental Protection Board, “Environment/Cellulose”, which focuses on the chemical character, distribution pattern and potential ecological hazards of chlorinated organic substances from pulp mills. This paper deals primarily with the spread of EOCl in the sediments of the Bothnian Sea and the northern part of the Baltic. Results:–there exists a clear linkage between the spread and the concentration of EOC1 in surficial sediments and the bottom dynamic conditions, such that high contents (highest 903 µg/g ds) generally appear close to the pulp mills and within areas of accumulation, and low contents (< 1 µg/g ds) appear in sediments from areas of erosion and transportation;–diffuse leakage from land, emissions from urban areas, or from steel and petrochemical industries do not seem to be of any major importance for this characteristic distribution pattern of EOC1 in sediments;–sediment core data indicate an ongoing increase in EOCl-contamination;–the concentrations of EOC1 in sediments from lakes and coastal areas far from any known pulp mills are low;–the main conclusion from these studies is that EOC1 is distributed over vast areas and that it is hard or impossible to find any areas in the Bothnian Sea unaffected by these substances.

It should be noted that in all assessments of ecological risks, it is important to have knowledge of the size and character of the impact areas, but that it may be difficult to select biological test organisms and actually establish ecological effects.
Biochemical Testing of Groundwater
Authors: Obst U. , Holzapfel-Pschorn A.
Published: May 2018

Several biochemical methods for easy testing of the microbial turnover activity, the microbial biomass, and toxic effects of pollutants are presented. These methods are simple, quick, and cheap and can be performed in every laboratory with standard equipment. Some examples of application in water and groundwater control are described. The presented results show correlations between enzymatic activities and organic compounds, between enzymatic activities and biomass, and also the influences of surface water on groundwater, and biological water treatment. The application of the described biochemical tests is proposed for samples of the whole water cycle in order to get more information supplementary to classical biological and chemical investigations.
The Effect of Unsaturated/Saturated Zone Property upon the Hydrogeochemical and Microbiological Processes Involved in the Migration and Attenuation of Landfill Leachate Components
Authors: Blakey N. C. , Towler P. A.
Published: May 2018

Landfilling of domestic wastes at ‘dilute and disperse' sites on the two major aquifers in the U.K., the Triassic Sherwood Sandstone and the Cretaceous Chalk, continues to highlight the vulnerability of groundwater resources. This paper describes the findings of hydrogeochemical and microbiological investigations designed to elucidate the processes of migration and attenuation of landfill leachate components which operate in the unsaturated/saturated zone.

Microbial enumeration has shown that bacteria colonise the unsaturated and saturated zones of the Chalk, and the investigated unsaturated zone profile of the Sandstone to a depth of at least 40 m. Domestic waste landfilling on the Chalk appears to result in an increased bacterial population. The high buffering capacity of this rock type has a significant impact on pollution plume development by counteracting the potentially low pH conditions, attributable to volatile acid components of landfill leachate, which inhibit biodegradation. In the Sandstone, increased bacterial populations only correlate with horizons where anaerobic biodegradation has been identified by pore water and gas profile analysis. The limited buffering capacity of this formation indicates that a substantial depth of unsaturated zone is required to provide dilution of landfill leachate so as to maintain biodegradation and significant attenuation of pollution plume development. Simple laboratory activity tests, using recovered core material incubated under aerobic conditions at 10 °C and dosed with a range of concentrations of volatile acid solutions, have highlighted the constraints on biodegradation associated with low buffering capacity.

The long term objective of these studies has been to provide data for landfill design assessments capable of achieving the high standards which present day environmental pressures demand.
Effect of Petrochemical Activated Sludge on Soil Properties
Authors: Tedesco M. , Ligo M. , Gianello C. , Simon Z.
Published: May 2018

Excess activated sludge produced at SITEL, the integrated wastewater treatment plant of Pólo Petroquímico do Sul (South Petrochemical Complex), situated in the municipality of Triunfo, State of Rio Grande do Sul, Brazil, is disposed of by subsurface injection on pangola grass fields at average application rates of 24 tons/years (dry basis). With the purpose of investigating the effect produced by the application of sludge at higher rates on the soil-plant-water system, as well as the response of more commercially valuable grass species, a growth-leaching pot experiment is being conducted at the Department of Soils of UFRGS (Federal University of Rio Grande do Sul), with the supervision of SITEL. After one year, comprehensive soil analyses showed the following results:Sludge decomposition in soil, worked out from evolution of CO2, amounted to 2.7% of C lost as CO2 in relation to the C added, in 50 days, 27°C (daylight temperature) and sludge application rate of 24 t/ha.Sludge application brought about an enrichment of soil C, N and P restricted to the top layer.No significant modifications were observed in soil pH and contents of K, Ca, Mg, Fe, Mn and B in the top layer of soil, even at the higher sludge application rates.Slight increases were observed in contents of Na, Cu, S and electrical conductivity of the top layer, effects compatible with the characteristics of the sludge applied.Appreciable increases were observed in soil contents of Zn, Cr, Cd and Ni, in correlation with the increasing sludge application rates. The resulting values, however, fell well below the tolerable limits.Proper management of a sludge application system that reproduces the conditions chosen for this investigation can yield a useful site life of many years without appreciable environmental risks.
Analysis of the Copesul Water-Oil Separation System
Authors: Leitão Antonio A. , Rangel Carla M. P.
Published: May 2018

This paper presents an overview of the water-oil separation system at COPESUL (Companhia Petroquímica do Sul). The design and operation of the system are discussed, and possible changes to be implemented to keep the oil and grease content of the effluent within the limits acceptable for its admission to SITEL (the integrated system of liquid effluent treatment of the South Petrochemical Complex). Since the start of operation, the system chosen, which includes a pre-separator and tiltable plate interceptor (TPI) water-oil separator, has experienced problems. The effluent generated has frequently had an oil and grease content above the limit set for acceptance by SITEL. The situation was investigated, and it was found that the problem was due to the following: operational conditions were different to the design conditions; oil with a density higher than water was present; there were deficiencies in the maintenance and cleaning systems. Various options were studied to eliminate these problems, and priority was given to increasing the capacity of the separation system, segregating the oil with a density higher than water at its source, and increasing the frequency of system maintenance. It was thought that these measures would result in an effluent oil and grease content less than 100 mg/l, and that the separation system would operate with greater flexibility.
Experience of 16 Years' Operation and Maintenance of the Fukashiba Industrial Wastewater Treatment Plant of the Kashima Petrochemical Complex – I. Operation and Maintenance
Authors: Okawa Y. , Shinozuka S. , Ota R. , Matsui S.
Published: May 2018

The Kashima petrochemical complex and the Fukashiba industrial wastewater treatment plant are described. The complex consists of 19 core factories (petroleum, petrochemicals, and thermal power generation) and 39 other factories (including organic chemicals, foods, metals, machinery, etc.). The total amount of industrial wastewater produced is 59,800 m3/day. The treatment plant also accepts municipal wastewater from the surrounding area, totalling 1,100 m3/d. A system for charging for the industrial wastewater has been introduced. The water quality standards for the industrial wastewater discharged to the sewerage system and the effluent of the treatment plant are described. The main treatment process is activated sludge with operational conditions of high dissolved oxygen and long solids retention time (SRT). These operational conditions solved the problems of high ammonia and refractory substances in the influent. Complete nitrification occurred under the low alkalinity conditions and the effluent COD was low due to the long SRT. Successful operation and maintenance were achieved by good co-operation between the factories and the treatment plant.
A Modified Tidal Prism Model for Water Quality in Small Coastal Embayments
Authors: Kuo A. Y. , Neilson B. J.
Published: May 2018

A water quality model was developed for easy application to small coastal embayments. The simulation of physical transport processes is based on Ketchum's tidal prism theory, modified and expanded such that it becomes applicable to cases where the embayment is branched and/or freshwater discharge is negligibly small. A model coastal embayment was divided into segments of lengths equal to local tidal excursions. Instead of starting the segmentation from landward end with freshwater discharge and tidal prism as two non-zero parameters, the modified model subdivides the water body starting from the seaward end with the difference between tidal prism and freshwater discharge as a single parameter. The mass balance within each segment was formulated by considering the exchange of water with its neighboring segments due to the flushing of freshwater discharge, as well as the tidal prism on ebb cycle, and to the mixing of the tidal prism on flood tide. This results in an algebraic equation which may be solved for concentration in each segment by successive substitution. For a non-conservative substance, the biochemical reaction terms may be easily added to the algebraic equation without complicating the solution scheme. The model has been applied to a number of tidal creeks and coastal embayments in Virginia, USA. The application to the Lynnhaven Bay is presented.
Musty Odour Problems in Lake Biwa 1982-1987
Authors: Yagi Masakazu
Published: May 2018

This paper discusses the results obtained by two research groups investigating the musty odour problem in Lake Biwa during the years 1967 to 1987. The study has shown that the problem is caused by the growth of three species of planktonic blue-green algae in the southern lake. These algae produce as metabolites either 2-methyl-isoborneol (MIB) or geosmin and it is these compounds which give rise to the musty odour. Recently the musty odour problem has expanded from western to eastern part in the southern lake. The occurrence of the problem has also changed from spring to early summer and more recently it has begun to appear also during the autumn months. The maximum concentrations for geosmin and MIB, 1,050 and 860 ng/l, recorded for the lake occurred in the autumn of 1985.
Earthy-Musty Odor-Producing Cyanophytes Isolated from Five Water Areas in Tokyo
Authors: Matsumoto A. , Tsuchiya Y.
Published: May 2018

Two kinds of 2-methylisoborneol-producing blue-green algae, Oscillatoriageminata and O.limnetica, and three kinds of geosmin-producing algae, O.amoena, O.splendida, and Aphanizomenonflos-aquae, were isolated from a park pond, a fish-cultivation pond, a river, and a reservoir. An oscillatorian species isolated from an air conditioning cooling tower was shown to yield both 2-methylisoborneol and geosmin simultaneously. Care was taken to ensure that the blue-green algae identified were those responsible for the musty odor compounds.
Behavior of Musty Odorous Compounds during the Process of Water Treatment
Authors: Ashitani K. , Hishida Y. , Fujiwara K.
Published: May 2018

Geosmin and 2-methylisoborneol (MIB) are two of the causative compounds responsible for the musty odor problem in drinking water. Geosmin and MIB in raw water were present both in solution and in a suspended form mostly associated with the host cyanobacteria. Geosmin and MIB in suspended form were well removed by coagulation and sedimentation alone. Geosmin present in solution could be removed almost to an undetectable level in the rapid sand filter of the pilot plant where no pre-chlorination was practiced. Breakpoint pre-chlorination, however, forced geosmin and MIB present inside of the host algae to leak into the water. The concentration of MIB decreased in a sedimentation basin during the daytime, but not at night in the plant practicing breakpoint pre-chlorination. Geosmin and MIB were both decomposed under sunlight in the presence of free residual chlorine.
Kinetics of Acetate and Methanol Conversion into Methane in Eutrophic Sediments and its Application in Anaerobic Systems
Authors: Naguib Monir
Published: May 2018

The methane production from sediments amended with acetate and methanol with and without peptone can be described by the Michaelis-Menten kinetics. The Lineweaver-Burk reciprocal plots reveal, in analogy to the kinetics of enzyme reactions, a clear defined pattern. Acetate underlies a competitive behaviour with different Km values of 7 and 2 mmolor in the absence and presence of peptone, however, with a common Vmax oF 0.3 µmoles CH4/g wet wt./d. Methanol shows, on the contrary, a non-competitive pattern with a common Km of 16.5 mmolar and different Vmax values of 0.2 and 0.5 µmoles in aged and fresh sediments which both increased to a common Vmax of 0.8 in the presence of peptone. The acetate pool in eutrophic sediments lies far below the determined Km values and hence acetate as such is restrictively available to methanogens. The stimulation of sediment methanogenesis amended with acetate through stimulants like peptone aims to lower the Km values and hence render methanogens a more favourable competitive potential. Stimulation of methanol methanogenesis is reflected in the increase in the Vmax with no influence on the Km values. Knowledge and proper application of determined kinetic parameters in anaerobic systems, e.g. in sewage treatment anaerobic towsrs, proved to be useful in manipulating an increased biodegrability and biogas production.
Biofilm Growth in a Drinking Water Network: A Preliminary Industrial Pilot-Plant Experiment
Authors: Haudidier K. , Paquin J. L. , Francais T. , Hartemann P. , Grapin G. , Colin F. , Jourdain M. J. , Block J. C. , Cheron J. , Pascal O. , Levi Y. , Miazga J.
Published: May 2018

Bacterial populations (measured as total, actively respiring and plate count) were analysed during drinking water transport within an industrial network pilot plant comprised of six loops serially disposed. PVC and cement coupons were exposed to the water flow using special sampling devices. In the absence of any residual chlorine, bacterial growth was rapid (doubling time 10 h) during the first 40 hours. Beyond that period plateau a stationary and even a decline phase may be observed. Fixed biomass is around 107 bacteria per square centimeter and decreased constantly with the distance from the feed point of the network. Substrate conversion really controls biofilm formation.
Monoclonal Antibody Based Immunofluorescent Assay for Giardia and Cryptosporidium Detection in Water Samples
Authors: Stetzenbach Linda D. , Arrowood Michael J. , Marshall Marilyn M. , Sterling Charles R.
Published: May 2018

Cryptosporidium and Giardia are enteric dwelling parasites that cause diarrheal illness. These parasites are present in numerous animal species and the potential zoonotic transmission to man via water is of increasing concern. Water samples collected from recreational sites throughout the State of Arizona were assayed for the presence of Giardia cysts and Crypto-sporidium oocysts using a qualitative presence/absence immunofluorescent assay with cell wall specific monoclonal antibodies developed in our laboratory. Seven percent of the water samples were positive for Giardia cysts while 30% were positive for Crvptosporidium oocysts. In addition, a quantitative assay was performed on each water sample for Cryptosporidium oocysts. The presence/absence qualitative immunofluorescent assay method proved to be a more efficient, sensitive and reliable means to detect these parasites in surface waters.
Ecological Study on Anaerobic Sludge Bulking Caused by Filamentous Bacterial Growth in an Anaerobic Contact Process
Authors: Endo G. , Tohya Y.
Published: May 2018

The authors observed a biological sludge bulking phenomenon which was caused by filamentously growing anaerobic microorganisms in experimental anaerobic contact processes (ACP) treating wheat starch wastewater. There are many kinds of anaerobic microorganisms which grow filamentously, like in activated sludge. One species of anaerobic bacteria caused serious sludge bulking, and it had thin rod (around 0.2 µ m in width) and long chained morphology. When acidogenically fermented starch wastewater was fed to the ACP, the thin rod microorganism was eliminated and the biomass concentration of the methanogenic fermentor was recovered. The microorganism which caused bulking phenomenon was enriched in a liquid medium containing raw starch (wheat starch particle). The microorganism grew in long chained filamentous form, degraded raw starch, and fermented mainly volatile fatty acids (acetate, propionate, butyrate and ethanol). From these results, it is revealed that acidogenic fermentation of wastewater containing raw starch prior to treatment by an ACP is effective to prevent the anaerobic sludge bulking and to keep high organic laoding of ACPs.