bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of Water Hyacinth in Tertiary Treatment of Domestic Sewage
Authors: Araújo H. , Clóris M. 
Published: May 2018

The objective of the present paper is the verification and quantification of the reduction of phosphorus with the use of water hyacinths in tertiary treatment of domestic sewage.
Secondary effluents from a small treatment station were run through a series of four tanks containing water hyacinths. Measurements and analyses were conducted in order to verify reduction of nutrients in the final effluent.
Results showed removal up to 88% orthophosphates (leaving 0.21 mg/l) for an average detention time of 5.44 days. The average flow was 3.3 m3 per day.
These encouraging results suggest the practical value of the method when there is the need of tertiary treatment for the sewage of small communities.
The Hornsby Bend Hyacinth Facility in Austin, Texas
Authors: Dinges Ray , Doersam Jim 
Published: May 2018

The Hornsby Bend Hyacinth Facility, the first such system built under the U. S. Environmental Protection Agency “Construction Grants Program”, represents the culmination of over a decade of experience at the City of Austin with hyacinth treatment.
The facility consists of three culture basins 265 m in length with an area of 1.6 ha. To permit year-round hyacinth culture, basins are covered with a 2.06 ha unitary greenhouse structure. Fenced exclusion areas at intervals along sides of basins serve as natural aerators and enhance fish production.
The system, operated in an aerobic mode, was designed to daily treat about three million liters of sludge lagoon supernatant. Exclusion of large vertebrate predators and stocking of basins with selected animal species will provide a unique ecosystem. Basins were planted with hyacinth in late October, 1985 and discharge commenced on February 3, 1986. Functional characteristics and ecological considerations of the facility are discussed and operational performance data are presented. Maintenance harvesting of hyacinth and disposition of plant material are described. Application of greenhoused hyacinth treatment systems are addressed.
Experimental Investigations into the Use of Emergent Plants to Treat Sewage in South Africa
Authors: Alexander W. V. , Wood A. 
Published: May 2018

South Africa is a relatively water-short country which has many rural communities with water-borne sewage infrastructures requiring low technology treatment facilities. In order to protect the water resources of the country the authorities have set high standards for effluent quality (COD &lt; 75 mg/l, NH3 &lt; 10 mg/l, E. coli &lt; 1000 and in some areas P &lt; 1 mg/l).
Traditionally, oxidation ponds have been used in these applications but have not been able to consistently meet the required standards and recently interest has been shown in artificial wetlands as a low technology means of solving the problem. As a result several experimental projects are at present being initiated in South Africa, both as primary and secondary treatment for domestic sewage and also as a tertiary treatment to remove nitrogen, phosphorus and E. coli from conventional sewage plant effluents.
The designs of these experimental projects are described in the paper and it is hoped that data will be available for presentation at the seminar.
Purification of Pisciculture Waters through Cultivation and Harvesting of Aquatic Biomass
Authors: Simeon C. , Silhol M. 
Published: May 2018

The study of thermal wastes from the nuclear plants around Pierrelatte for agricultural, piscicultural, energy and environmental protection purposes resulted in the establishment of a pilot facility as early as 1976.
An aquatic macrophyte pilot facility has been operational since 1983 to study the use of water hyacinths from the aspects of energy and ecology. The results obtained suggest that production yields for the 7 month growing period should exceed 60 metric tons (MT) (dry weight) per hectare in a European climate, and that such crops can feasibly be cultivated in temperate regions.
The pilot facility is supplied with pisciculture effluent water, making it possible to quantify the stabilization power of the plants. Without primary decantation, with a retention time of 4 days and stabilization with water hyacinths only, the organic matter waste pond surface area required is 3.5 m2/m2 of pisciculture pond. Any primary or secondary facilities will lead to a reduction of these areas. The final decision will depend on the economical optimization of all the wastewater.
The Role and Problems of Monitoring Bottom Sediment for Pollution Assessment in the Coastal Marine Environment
Authors: Literathy P. , Nasser Ali L. , Zarba M. A. , Ali M. A. 
Published: May 2018

The role of bottom sediment in pollution assessment of surface water and the problems related to its characterization were reviewed and identified. The importance of data validation in monitoring bottom sediment was recognized. The effect of grain size distribution and of spatial variations in the bottom sediment justified a sound sampling and analytical protocol.
Analysing the clay-silt fraction to reduce the effect of grain size was shown to be reliable. Before monitoring, however, one should prove that bottom sediment characteristics are homogeneous horizontally around the sampling site. Due to vertical sediment stratification from temporal variation of pollution, identification of the sediment layer to be monitored is of the utmost importance. It was found that “double sampling”, i.e., simultaneous sampling of the surface and the top 1 cm of the sediment layer provided representative data when redistribution of the bottom sediment is within acceptable limits. When characterizing the release of carbonate-bound phosphates and heavy metals from sediments, the multistage extraction technique with carbon dioxide was found to be effective. It was concluded that pollutant dynamics and the impact of the intertidal zones on the coastal marine ecosystem could be evaluated by monitoring the sediment, interstitial water, tidal creek and tidal waters simultaneously.
Advantages of Dual-Media Dry Filters in Biological Wastewater Treatment
Authors: Richard Y. , Seyfried C. F. 
Published: May 2018

SUMMARY
The main and original features of dry filtration are reviewed. Forced aeration increases the aeration capacity of the process. In addition, the dual layer of media results in a better control of the elimination of both dissolved pollution and that connected with suspended solids. The treatment of various waste water in which the ratio between soluble and insoluble pollution was varied, made it possible to differentiate the way in which each is removed. This study lasted for one and a half years with 10 month's actual testing on two separate pilot plants. The contact time was related to the water and air flow rates as well as the degree of cloqqinq. The effect of the type of support media and the rates of flow of the various fluids were studied and the result led to recommendations being set for application of the process on an industrial scale.
Process Alternatives for Enhanced Biological Treatment Efficiency of Forest Industry Effluents
Authors: Mehner A. , Morange H. , Rintala J. , Silvo R. , Viitasaari M. , Vuoriranta P. 
Published: May 2018

Biological wastewater treatment methods are being used at an ever increasing extent for the treatment of wastewaters from the Finnish forest industry. Conventional activated sludge processes treating the composite wastewaters from the mill are most commonly used.
Present plants may turn out to be inadequate in some cases, or they may not serve the purpose. This can happen for example when 1) the process fails or the running costs become extremely high, 2) the legal regulations concerning the quality of the treated wastewater change or 3) production of the mill expands or is diversified. These situations can be handled by expanding the existing treatment capacity. An alternative is to develop specific additional treatment units more appropriate for the wastewaters in question.
In this paper the advantages and disadvantages of some biological process units completing activated sludge treatment plants are studied. In experimental studies a, b and c, a two-stage activated sludge process, a modified activated sludge process and an anaerobic pretreatment, respectively, are examined. The results of these studies show that a selective, highly loaded first stage of a two-stage activated sludge process can efficiently equalize and improve effluent quality, especially when the suspended solids concentration in the influent is high (Study a), that an anoxic/anaerobic unit together with a small aerated contact unit combined with a conventional activated sludge process can reduce phosphorus levels in the effluent (Study b), and that anaerobic pretreatment of concentrated wastewaters efficiently reduces the organic loading, improves sludge settling properties, and reduces sludge yield and phosphorus demand (Study c).
Improving the Settling of Activated Sludge by Chemical Additives
Authors: Demel I. , Möbius C. H. 
Published: May 2018

One of the main problems encountered in biological waste water treatment plant of papermills is poor settling of activated sludge in secondary sedimentation tanks. In many cases, activated sludge volume indices stay above 150 ml/g. Moreover, bulking of sludges in activated sludge plants of papermills is more frequent than usual. Bulking sludge is characterized by excessive growth of filamentous microorganisms.
In a lab-scale activated sludge plant, tests were made to improve the settling of activated sludge by adding the following chemicals: Lime, alkaline activated bentonite, powdered lignite coke, polyelectrolytes used as flocculants.
The findings reveal that dosage of the above additives actually gives improved sedimentation. Moreover, biochemical degradation becomes more effective if bentonite and powdered lignite coke are added. Test results are evaluated to determine the extent to which settling of the activated sludge and plant efficiency are improved, taking into account operational and waste water parameters. Using lime, bentonite, lignite coke or polyelectrolytes is an economic method of fighting or preventing acute or permanent problems caused by bulking sludge and high sludge volume indices.
Ground Water–A Living Ecosystem
Authors: Seppänen Harri 
Published: May 2018

Many living organisms affect the quality of the ground water. Precipitation and/or solubility of many inorganic compounds depends in some way or other on biological activity of living organisms. The role of bacteria and other organisms in these processes may be either direct or indirect.
The oxygen consumption as a result of the decomposition of organic compounds is one of the most important processes affecting the quality of the ground water. In anoxic environments both iron and manganese are reduced becoming soluble in the ground water.
In weakly buffered ground water the release of the carbon dioxide during decomposition of organic substances decreases the pH of the water promoting the solubility of iron and manganese.
Most of the bacteria living in the ground water are psychrophilic and are attached on soil particles. Only few types of bacteria are free living.
Groundwater Investigations in the Lavia Deep Drilling Hole-Sampling Techniques and Results
Authors: Lampén Paula H. , Nikula Anneli 
Published: May 2018

The Industrial Power Co. Ltd (TVO) studied the final disposal of spent nuclear fuel in Finnish crystalline bedrock. During the years 1984-85 preparative work for the execution of site investigation was carried out. The tests of investigation methods and equipment have been carried out in a 1000 m deep test borehole at Lavia, Western Finland. Geophysical and hydrological borehole investigations have been carried out and groundwater samples taken.
As a part of TVO's R & D work Imatran Voima Oy (IVO) has planned and built new equipment for groundwater sampling and chemical field measurements in deep boreholes with a minimum diameter of 56 mm and a maximum depth of 1000 m.
The borehole assembly of the groundwater sampling equipment comprises an inflatable double packer system and a membrane pump. It is connected via hoses to a mobile unit consisting of a flow-through-cell system with electrodes and a micro-computer for automatic control and data processing (Fig. 1). Nitrogen gas is used to inflate the packers and to drive the membrane pump. The specific conductivity, amount of dissolved oxygen, pS, pH and Eh of the groundwater sample are measured in a system of four flow-through-cells before the sampled water gets into contact with air.
Using this instrument groundwater samples were taken from the test borehole in three stages, at five depths in the borehole. The concentration of iodide, the tracer of the drilling fluid, was frequently controlled during sampling. Several different physico-chemical analyses was performed comprising e.g. the main cations and anions and trace elements. Also samples for isotopic and gas analyses were taken.
According to field measurements and laboratory analyses, the groundwater seems to have a low ionic strength with no considerable variation in depth. Rather reducing conditions (minimum Eh about −450 mV) were observed below the depth of 400 m. Especially data from isotopic analyses gives evidence of mixing with drilling fluid. In spite of the disturbances in groundwater caused by drilling fluid and vertical flow in the open borehole the samples can be considered representative enough in evaluation of the general ionic composition of the groundwater.
The experience gained from the groundwater sampling at Lavia has had a significant influence on planning the future groundwater sampling during field investigation for the years 1987–92.
Chemical, Mineralogical and Microbiological Factors Affecting the Precipitation of Fe and Mn from Groundwater
Authors: Vuorinen A. , Carlson L. , Seppänen H. , Hatva T. 
Published: May 2018

Precipitation of hydrous Fe and Mn oxides was investigated in 12 plants, constructed for purification of groundwater from excess Fe and Mn. The re-infiltration method was applied in 7 plants and the slow sand filtration in 5 plants (Hatva et al., 1985; Hatva 1987, this symposium)
Water was analysed for aquatic chemistry and for the speciation of Fe, Mn, Zn and Cu. The distribution and mode of occurrence of the elements in the precipitates were studied by successive extraction and dissolution kinetics techniques. The mineralogy of the oxidic Fe and Mn precipitates was studied using XRD techniques.
The results suggest the presence of Fe(II), Mn and Zn in groundwater mainly in cationic form. Cu was in colloidal and organically bound forms.
The precipitation of hydrous Fe and Mn oxides from groundwater is affected by chemical and microbiological factors. The oxidation of Fe(II) took place mainly chemically with increasing O2 content, pH and Eh of the water. Ferrihydrite, a poorly ordered oxidic Fe mineral was the dominant product. Environmentally controlled colloidal and surface chemical properties of the precipitating species enhanced the precipitation causing sorption and scavenging of Si and cations. Owing to the relatively high Si content (over 4 mg Si/l) of groundwater in Finland and the interaction of Si and Fe the crystallization of lepidocrocite that is formed in Si-free systems was inhibited and ferrihydrate was formed instead.
15-20% of total Fe and above 50% of total Mn were in sorbed form in the precipitates. Only 15-20% of Mn was in sorbed form in the precipitates that contained MnO2 minerals, vernadite and birnessite (in two plants).
The oxidation of Mn(II) appeared to involve microbial catalysis because it was adversely influenced by high pH and copper sulphate.
The freshly precipitated MnO4 strongly sorbed and scavenged heavy metals (e.g., Ag, Sn, Ni, Co, Zn and Cu). Cations (Ca2+, Mg2+, K+ and Na+) were sorbed by the hydrous Fe oxides at high pH (above 7) whereas Cu tended to be sorbed at low pH levels.
Gallionella was the dominant type of bacteria in the raw water and the bacterial density was low. In the filtration basins Leptothrix, Siderocapsa and Ochrobium were the typical microorganisms. The bacterial density was highest in the upper part of the sand in the infiltration basins and the bacteria were covered by Fe (and Mn) precipitate encrustations.
Evaluation of the Efficiency of a New Aeration System at Henriksdal Sewage Treatment Plant
Authors: Reinius L.-G. , Hultgren J. 
Published: May 2018

Henriksdal sewage treatment plant is the largest plant in Stockholm with a design flow of 370 000 m3/d. In one aeration tank of eleven a new fine-bubble aeration system has been in operation since August 1985. The tank is divided into 6 equal parts. The first part is an anoxic zone and the other five are aeration zones with tapered diffusers. Several instruments are installed in the block including separate air flow monitors in each of the five zones and D.O.-probes in the inlet and outlet of the zones. Equipment for flow measurement of settled sewage and return sludge is also installed. Every instrument is connected to a computer for data acquisition.
To evaluate the efficiency of the aeration system the oxygenation transfer capacity has been calculated from the oxygen massbalance equation for each zone as a function of air flow. To solve this equation the respiration has to be known and this is done by a simple respirometer for samples of the MLSS in each zone.
When the KLa-values are known as functions of the air flow the mass balance equation can be used to calculate the respiration rate in each zone. The computer has been logging data for 2 2 months, and it is possible to calculate the respiration rates in the different zones every hour during this period.
It is very important to know the respiration along the tank and how it varies to get the optimal tapering of the diffusers when it is time to change the aeration system in the other 10 tanks. The calculations show a different pattern in the respiration over the year depending on the rate of nitrification. Another use of the calculation of the oxygenation transfer efficiency is to recognize if any long-term change occurs due to clogging of the diffusers.
Anaerobic-Aerobic Treatment of Industrial Wastewater
Authors: Bode H. 
Published: May 2018

The paper evaluates the question of whether a combined anaerobic-aerobic or a solely aerobic treatment of some particular industrial wastewaters leads to better results. Therefore three different industrial wastewaters were treated in two different process lines: one line consisted of anaerobic treatment prior to aerobic treatment and in the other, only aerobic treatment was applied. The experiments were run with wastewater from:–the pectin industry–the sugar industry (beet sugar)–the animal pulp industry.
The data presented in this paper were gained from experimental work which was conducted over a period of two years. Different scales of treatment plants were used. The anaerobic treatment was done in full- and semitechnical scale reactors, while the aerobic treatment took place in labscale and semitechnical scale plants.
Surprisingly in all three cases the solely aerobic treatment led to slightly better results in terms of residual pollution.
Finally the paper presents data gained from a recently built, full-scale anaerobic-aerobic process which treats pectin waste. The aerobic stage of the process was designed on the basis of the results from the experimental work which was mentioned above. The results from the former experimental work and from the full-scale operation are compared.
Study on Transport and Material Balance of Nutrients in Yamaguchi Estuary (Japan)
Authors: Ukita Masao , Nakanishi Hiroshi , Sekine Masahiko 
Published: May 2018

The transport and material balance of nutrients in the Yamaguchi Estuary were studied using environmental impact assessment (EIA), in order to investigate the effects of the reclamation of tidal marshes. The main methods utilized were: 1. a topographical survey; 2. pollutant load analysis; 3. water sampling during one tidal cycle; 4. sediment quality analysis; 5. box model analysis of water quality; 6. modelling of the ecological system including fish.
The main results obtained were as follows: 1. after the reclamation of 348 ha, the volume of the estuary, tidal prism, and tidal marsh area decreased by 6.5%, 12%, and 11%, respectively; 2. pollutant loads have increased from 1.38 to 1.69 t/d for N and from 0.09 to 0.18 t/d for P; 3. upward transport of suspended solids (SS) was observed under fine weather conditions, especially in the summer; 4. sediments in marsh areas exhibited higher values of oxygen consumption rate and nutrient recycling rate; 5. the net settling velocity of SS in the river mouth area was 1 to 3 m/d; 6. most of the SS transported up the estuary seemed to be flocculent organic matter; 7. the results of the box ecosystem model simulation indicated that there will be a net input of fish from the open sea area.
Some Studies to Reduce Sedimentation in a Port on a Tidal River
Authors: Müller K.-D. , Schwarze H. 
Published: May 2018

Sedimentary material containing harmful substances dredged from seaports has become an increasing problem over the past few years. A main part of the sediment, mostly silt, contaminated with heavy metals, settles out in the region of harbour entrances. The reasons for this problem are explained.
For a huge harbour basin of the Port of Hamburg investigations in a physical model had been carried out to find measures for reducing the sediment intrusion into the harbour basin. The following shows possible reconstructions of the harbour entrance in consideration of the navigation and their expected influence on the sedimentation transport into the harbour basin.
Effect of Chelating Agents on the Growth of Blue-Green Algae and the Release of Geosmin
Authors: Miwa M. , Morizane K. 
Published: May 2018

The effect of chelating agents on the growth of Anabaenamacrospora, a planktonic blue-green algae, and on its production of geosmin was studied.
When A.macrospora was cultured in CT medium containing EDTA (an artificial chelator), the maximum cell numbers were about 1×106 cells/ml. However, in an EDTA-free CT medium, the maximum cell numbers were a tenth of the normal growth level in the complete medium. In addition the chlorophyll-a content was reduced almost a fourth and the color of the algal cell bodies changed from green to yellow. These results showed that growth of this alga in a chelator-free medium was not healthy. At this time, though the geosmin content was constant and in the same range of 1.0-4.0×10−5 ng/cell as in the complete medium, the ratio of the extracellular geosmin concentration in the medium to the gross concentration was 2:10 to 3:10 and 2 to 3 times its normal level. It was considered that the deterioration of alga's physiological condition increased the release of geosmin to the medium. These results suggested that the extracellular concentration of geosmin produced by A.macrospora was affected by the alga's physiological condition. Finally EDTA can be substituted by humic acid. When this alga was grown in a medium containing humic acid instead of EDTA, the maximum cell numbers and the release ratio of geosmin was of the same level as in the case of the complete medium.
Lake Tinaroo (Australia) – Towards a Management Plan
Authors: Souter W. D. , Flanders J. D. 
Published: May 2018

Tinaroo Falls Dam provides a water supply for irrigated agricultural production, primarily tobacco, rice, tree and horticultural crops, near Mareeba in Far Northern Queensland.
The increasing popularity of Lake Tinaroo as a recreation and tourist venue is providing impetus for a management plan to be prepared for the lake. Urban and agricultural use of the catchment has caused a change in the trophic state of the lake.
The competing uses and emerging issues in relation to a sustainable, healthy lake are discussed.
The QWRC is desirous of establishing a management plan for the catchment. Progress in implementing such a plan is discussed.