bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enlargement of Sewage Treatment Plants for Nitrification by Use of Subsequent Rotating Biological Contactors
Authors: Nyhuis G. 
Published: May 2018

The surface-specific nitrification performance of Rotating Biological Contactors (RBC) has been improved considerably by the use of new techniques. Maximum nitrification rates of 3.3 g/m2×d (10 °C) were achieved, which cannot be approached with any other known procedure. This high oxidation efficiency is achieved with Rotating Biological Contactors by using two new measures:A large degree of separation of carbon degradation and nitrogen oxidation through filtration of the waste water before the subsequent nitrifying RBC stage, whereby the environmental conditions for the nitrifying bacteria are improved, especially in respect of an optimised supply of oxygen.Periodic reversal of the direction of flow in the RBC stage which is constructed as a cascade. This measure allows the attainment of a uniform thickness of nitrifying bacteria growth in all the compartments, which has a particularly advantageous effect in the case of unavoidable surges in load.
Because of the low production of excess sludge in the nitrification stage, a subsequent stage for separating solids is not necessary. In this paper experiences with the upgrading of a full scale rotating biological contactor plant and the measuring results from an enlarged oxidation pond installation are summarized.
Intermittent Cycle Extended Aeration System (ICEAS R) for Small Wastewater Treatment Plants
Authors: Khararjian H. A. , Callaway W. H. , Cardinal P. , Meany J. 
Published: May 2018

Many municipalities and industrial plants with small quantities of wastewater are facing challenges with providing economical treatment strategies. They require simply designed and operated processes which give high quality effluent.
One such process is the Intermittent Cycle Extended Aeration System (ICEAS R). This is a variant of the activated sludge biological process which allows continuous inflow of raw wastewater and intermittently discharged influent. It provides flow equalization, biological oxidation and sedimentation with decanting of supernatant in a single tank. The process can be operated on any cycle duration based on the required degree of treatment. Each cycle consists of aeration, sedimentation and decantation phases. The aeration phase can be operated on an oxic/anoxic mode for the purpose of nitrification/denitrification and biological phosphorus removal.
To date, there are more than 100 plants worldwide and 25 within the U.S.A. that are built and operating successfully. High degrees of BOD, suspended solids and nitrogen removal are obtained with the plants. Most of the small plants require minimal operating personnel, generally one or two, for continuous operation.
Tertiary Waste Water Treatment with Flotation Filters
Authors: Kiuru H. J. 
Published: May 2018

Tertiary waste water treatment has been usually carried out by adding filtration after an activated sludge process, which can be fitted with pre- or simultaneous precipitation for removal of phosphorus. Filtration is operated either as a mechanical unit operation for upgrading the removal of suspended solids only, or as contact filtration where the precipitation of phosphorus is boosted with a minute dose of trivalent iron or aluminium.
Instead of using conventional downflow filters, tertiary treatment can also be carried out with flotation filters where flotation is accomplished in the head above the filter, necessary for filtration in any case. The possibility of using flotation between secondary clarification (sedimentation) and filtration, when it is needed, results in a very good load bearing capacity and in a high degree of removal of solids.
This means that excellent operational results can be achieved with an almost complete reliability in all operational circumstances at a very reasonable cost. Long experience in Finland from a medium size (30 000 pe) activated sludge plant with simultaneous precipitation fitted with flotation filter tertiary treatment in 1984, shows that values of BOD7 ≤ 5 mg/l, Ptot ≤ 0.3 mg/l NH4-N ≤ 1 mg/l and of suspended solids ≤ 5 mg/l can be continuously achieved, in the treatment of municipal waste water where total nitrification is applied.
Development of a Two-Stage Treatment Plant for Extensive Nitrogen and Phosphorus Elimination
Authors: Bahre G. , Firk W. , Gassen M. 
Published: May 2018

The report describes low-cost development and design of a two-stage wastewater treatment plant for 90,000 PE to achieve the highest possible degree of phosphorus and nitrogen elimination. The receiving water body of the treatment plant is a small watercourse fed almost exclusively by treated wastewater. A significant improvement in the water quality of this watercourse is planned. In particular, the performance of the wastewater treatment plant will need to be enhanced. The plant operator, the Erft River Board, organized a competition to attract solutions for an appropriate development of the plant from several consultants. Apart from embodying the concept of extensive wastewater treatment, designs were expected to preserve the existing infrastructure of the two-stage treatment plant as far as possible.
Following selection of the most suitable design, the intended process technology is currently being tested in a pilot-scale plant. Planning envisages advanced wastewater treatment processes, including enhanced biological phosphorus removal, chemical precipitation/flocculation, nitrification and denitrification and combined coagulation/filtration. The pilot-scale investigations are carried out in close co-operation between the water authorities, the plant operators, the consultant, and a university institute of sanitary engineering.
The paper presents the design and first results of the pilot-scale investigations in terms of the parameters BOD5, COD, phosphorus, ammonia and nitrate.
Sediment Movement into the Combined Trunk Sewer No. 13 in Marseille
Authors: Laplace D. , Sanchez Y. , Dartus D. , Bachoc A. 
Published: May 2018

The AGHTM, a French technical association, supports a research program on the transfer of solids into sewer networks. It aims to better understand how sediments develop in trunk sewers and what can be their contribution to wet-weather pollutant discharges. The priority is given, during the first phase, to observation, especially inside the combined trunk sewer n° 13 in Marseille. Various parameters such as sediment depth, water level, flow velocity fields, sediment particle size or mechanical characteristics are measured. Certain conclusions have been reached. For example, we have been led to form some assumptions, such as:
– the volume of sediment increases substantially, principally at the entry points, during the first rainfall events, it decreases during the three days following rain, and seem to become stable after several months; – the solids deposited in the sediment are much larger than those which make up the most part of pollutant discharge during wet weather.
Constructed Wetlands for Wastewater Treatment: The New Zealand Experience
Authors: Bhamidimarri R. , Shilton A. , Armstrong I. , Jacobson P. , Scarlet D. 
Published: May 2018

The use of constructed wetlands which mimic natural marshlands, represents an innovative approach to wastewater treatment. They make use of diverse ecological mechanisms to renovate wastewater. They are inexpensive to construct and operate with minimal energy requirements. Unlike the conventional technologies, wetlands provide low volumetric reaction rates and therefore are suitable for small-scale applications.
The majority of constructed wetlands in New Zealand are used for the treatment of domestic wastewaters from small communities for secondary treatment and pathogen removal. There are over 20 constructed wetlands in New Zealand receiving wastewater flow rates ranging from 7.5m3/day to around 4500m3/day. Both surface-flow and subsurface-flow wetlands are used. The performance data from three wetland systems treating septic tank effluents are presented and their treatment efficiences are discussed.
Development of Design Criteria for the Chemical Precipitation Process Applied in Cracow Wastewater Reclamation System
Authors: Rybicki S. M. , Kurbiel J. 
Published: May 2018

The results of investigation on coagulation as tertiary treatment of secondary effluent in the water reuse process for industrial application are presented. The investigations were carried out at the municipal wastewater plant in the city of Cracow.
The experimental model has been operated continuously under dynamic flow conditions; the paper describes the construction of the model as well as the experiences gained during its operation. The investigations which were carried out in the laboratory batch tests are also described.
The studies were conducted using alum, ferrous sulphate, lime, an alum combined with lime and ferrous sulphate combined with lime doses. The best effectiveness of orthophosphorous removal was found for alum /96.2 %/ and ferrous sulphate combined with lime /84.2 %/. The best results of permangante COD removal were reached for ferrous sulphate /52 %/ and ferrous sulphate combined with lime /51.3 %/.
In the paper the suitability of experimental models and procedure for experimental data evaluation in development of design criteria are presented.
The Use of a Turbulent Pipe-Flow for Rapid Flocculation of Precipitate in the Electroplating Wastewater Treatment
Authors: Kurbiel J. , Sapulak A. , Schade H. 
Published: May 2018

The paper presents the results of an experimental pilot study on advanced flocculation of metal hydroxides that are precipitated from electroplating wastewater during pH-adjustment. A pipe-flocculator with a turbulent flow, to ensure proper mixing conditions, was used instead of a classical flocculation tank. The results of the study indicated a high efficiency of the process. The flocculation proceeded within 50-100 seconds, which was much less than is required during classical flocculation. Application of a pipe-flocculator results also in reduction of both capital and operating costs of the wastewater treatment plant.
In conclusions, important conditions, which are indispensable if pipe-flocculation is to be used, were formulated.
Dual Distribution Systems: The Public Utility Perspective
Authors: Johnson William D. 
Published: May 2018

Diminishing water resources are a worldwide problem. Many countries face serious water supply issues in the near future.
The United States has not escaped the problem of providing adequate water for its needs. Rapid population expansion in semi-arid locales, and growth in areas where groundwater resources are sensitive to saltwater intrusion have forced local officials to search for alternatives to satisfy a growing demand for water.
The City of St Petersburg, Florida, developed and is operating one of the world's largest urban water reuse systems. The program has been very successful in reducing potable water demands. The city has learned a great deal during the past fourteen years that the system has been in service.
The purpose of this paper is to share the history of the development of the St Petersburg Water Reuse System and what has been learned during its operation.
Pollution of the Outer Oslofjord
Authors: Baalsrud Kjell 
Published: May 2018

The Outer Oslofjord has recently been subject to concern.
1. The Inner Oslofjord. Covers an area of 193 km2, is 160 m deep and is separated from the Outer Oslofjord by the narrow Drøbak sound with a sill depth of less than 20 metres. This part of the Oslofjord constitutes an enclosed body of sea water, sensitive to pollution, receiving sewage from approximately 650,000 inhabitants. In spite of modern sewage treatment, the fjord still suffers torn eutrophication problems resulting in reduced oxygen in the deep water, and areas of anoxic bottom water. The fjord is an important recreation area.
2. The Outer Oslofjord. Recent findings indicate that eutrophication is slowly increasing. An increasing eutrophication of the Outer Oslofjord wil also increase the need (and cost) of better sewage treatment in the Inner Oslofjord.
3. The North Sea. The quality of the water in the Oslofjord area is also dependent on the water it receives from the Skagerrak. The Skagerrak water will periodically receive polluted water from the southern North Sea and Kattegat. When these episodes coincide with water renewals between the Oslofjord and the Skagerrak, the fjord will receive polluted water from other countries. The Oslofjord water will in turn discharge into the Skagerrak, but due to the general circulation pattern, this will mainly influence the Norwegian south-east coast.
Nutrient Removal in a Short Retention Time Sewage Treatment Plant
Authors: Karlsson Ingemar 
Published: May 2018

Chemical treatment of sewage water is today often considered as a method for phosphorus reduction and used in combination with biological treatment. The experience in Scandinavia, however, shows that chemical treatment alone gives beside a good phosphorus removal also a high BOD reduction. Due to the very low investment cost for such a process it has been adapted in Scandinavia as an alternative to biological treatment. Where the demand is for greater sewage treatment the most feasible method is to complement the chemical precipitation process with a compact biological treatment.
In Sweden the dominating post (and also the simultaneous) precipitation process has in many plants been replaced by a chemical pre-treatment process, because with pre-precipitation most of the organic matter is coagulated and extracted already in the primary clarifier. The energy demand in the biological process will decrease. The organic matter in the sludge will increase, which in an anaerobic digester means more digester gas.
The unloading pre-precipitation effect can also give advantages for nitrification. The important BOD/TKN ratio is decreased. It is possible to build up a high sludge age and to upgrade a plant without tank expansion to a nitrifying plant. Pre-precipitation is normally not influencing the readily degradable BOD, which is about 25% of the total BOD and therefore a perfect electron donor for pre-denitri-fication is still available.
The pre-precipitated sludge contains 75% of the organic matter in the sewage and can by hydrolysis be converted to readily degradable organic matter, which presents a valuable carbon source for the denitrification process. The hydrolysation process can be performed by, for instance, anaerobic treatment or heat treatment. This paper will review experiences from full-scale applications as well as pilot plant and laboratory studies.
The Behaviour of Vinasse Constituents in the Unsaturated and Saturated Zones in the Botucatu Aquifer Recharge Area
Authors: Gloeden E. , Cunha R. C. A. , Fraccaroli M. J. B. , Cleary R. W. 
Published: May 2018

Vinasse has been widely replacing chemical fertilizers in sugar cane plantations as a source of nutrients, mainly potassium. Despite its value as a fertilizer, which has already been shown, there are very few publications about the mobility of its constituents as well as their effect on groundwater quality.
In a sugar cane plantation located on the Botucatu aquifer recharge area, a research project has been developed to determine the dynamics of the constituents of vinasse through the unsaturated and saturated zones, aiming at defining the agronomic rate of vinasse irrigation in order to preserve the groundwater quality.
Geological and hydrogeological surveys were carried out utilizing data from geophysical methods (electromagnetism and electroresistivity), boring and piezometers.
The area wasdivided into three plots where vinasse was applied at rates of 150 and 300 m3/hectare.
A monitoring net was installed after the hydrogeological characterization of the site, consisting of monitoring wells, multilevel piezometers, tensiometers, suction and pan lysimeters, which allow the evaluation of the water flow and solute transportation through the unsaturated and saturated zones.
This paper shows the preliminary results of the monitoring and the methodology used.
Incinerator of Chlorinated Hydrocarbons Solid Wastes
Authors: Setti H. 
Published: May 2018

Fifteen years ago our Company bought an old factory of chlorinated products. Later our Company found that solid chlorinated residues had been thrown in to a completely inadequate soil.
After having determined the sites contaminated several solutions were thought through: artificial deposits, old granite mines, etc., none of them adequate. Finally the incineration process was chosen and approved by authorities. Today the installation is built and operates according to requirements.
Risk Assessment Methods for Establishing Clean Closure Levels
Authors: Riggenbach J. D. , Streeter R. A. , Hess S. C. 
Published: May 2018

Establishment of clean closure concentrations for low levels of hazardous constituents in soils, ground water, and other environmental media by assessing risks to human health and the environment is a tool that is being used with increasing frequency. The four-step process sanctioned by the U.S. Environmental Protection Agency (EPA) includes: 1) hazard identification, 2) exposure assessment, 3) toxicity assessment, and 4) risk characterization. This paper describes the methodology and applies it to the closure of a hazardous waste surface impoundment in Florida. To date, the closure process has taken nearly five years and, pending the EPA's and Florida Department of Environmental Regulation's (FDER's) final approval, will result in clean closure of a small facility that has spent in excess of $450,000 U.S. during this period for removal of 516 cubic metres of sludge and other solids. If clean closure is approved, as is concluded to be protective of human health herein, the facility owner stands to save $275,000 U.S. that is estimated would be required to monitor ground water and to maintain an impermeable cap for the 30-year post closure period currently required under U.S. and Florida regulations.
The risk assessment discussed in this paper began when soil samples collected after excavation of 516 cubic metres of sludges, soils, and other solids showed that the preliminary soil closure levels sanctioned by the FDER for chromium and nickel had not been achieved. Continued excavation would have cost a minimum of $50,000 to $100,000 U.S. (in 1988 dollars) and still may not have reached closure levels for these two metals. It is concluded in this paper that the maximum levels of chromium and nickel remaining onsite after remedial excavation (2.1 and 3.7 mg/kg, respectively) do not pose a risk to human health, and that the agency could raise the allowable closure level for these two metals from the current values of 1.1 and 0.70 mg/kg to these maximum values.
Solidification of Metal Finishing Slurry with Cement
Authors: Cláudio J. R. 
Published: May 2018

From July, 1986 to March, 1987, the author developed laboratory, tests on cementation of electroplating wastewater treatment sludges. Perfomed at the laboratories of Escola Politécnica of the University of São Paulo and of CETESB, tests were conducted with three types of cement produced in Brazil: CPC - Portland Cement, POZ pozzolanic cement and CAF - blast furnace cement. The tests had the following steps:–characterization of electroplating industry wastewater treatment sludge and study of the sludge - cement mixtures;–preparation of sludge - cement mixtures with 3 different water/cement ratios;–measurements of mixture consistency with Casagrande soil mechanics equipment;–determination of leaching quality and resistance to compression of solidified specimen at 3 ages;–analytical determination in the sludge-cement mixture;–test for solubility in water;–analytical determination of cyanide and heavy metals in the cure water of specimen.
Results showed that solidification with cement is an efficient technology for the fixation of toxic metal ions such as Cd, Hg and Pb and other metals such as Cr, Ni, Cu or Zn present in large concentrations in electroplating wastewater treatment sludges. With the only exception of Al+++ the other metallic ions determined in the leachate showed concentrations below drinking water standards. As to mechanical resistance after 90 days, the sludge - cement mixtures presented a performance similar to that of structural concrete.
Rhineland on the Way to its Thousandth Anniversary or Water-Administration in the Next 100–200 Years
Authors: baron van Tuyll van Serooskerken E. H. 
Published: May 2018

An inventory is made of the effects of sea level rise and expected climatic change on the level of the district water authorities in the Netherlands and especially the “hoogheemraadschap” of Rhineland in the next 100-200 years. Special attention is paid to the effects on land utilization, coastal defence and water control.
The first is hard to describe by lack of research, the second can already be determined in terms of cost; the third can be described in its effects on brackishness and water provision with indication of policies and measures to be taken.
Preliminary conclusions are that larger efforts on coastal defence - even with present techniques - will be a realistic answer in terms of cost. The foreseen increase of brackishness in area and salt concentration, will give a significant extra need for fresh water.
High cost and even higher risks have to be expected with regard to measures to neutralize the effects of a water surplus in winter and a growing water shortage in (late) summer, while the cost will further grow. Because of the effect a larger area must be drained off and water has to be raised higher as the Netherlands will sink in relation to the North Sea.
Sewage-Related Impact on Kuwait's Marine Environment – A Case Study
Authors: Al-Muzaini S. , Samhan O. , Hamoda M. F. 
Published: May 2018

This paper overviews the marine environmental impacts associated with Kuwait's liquid wastes, whose volume has grown considerably over the last two decades and is expected to grow further. The characteristics of local sewage, its collection, handling and treatment practices, and routes of input into the local marine environment are described. Realized or potential environmental impacts are discussed.
Sewage discharge has been found to exert different impacts on Kuwait's marine environment, ranging from fish kills and localized smothering of benthic organisms and microbial pollution to potential wider impacts on overall marine productivity. These impacts are due to a combination of unique local environmental conditions (e.g., high ambient air temperatures, high rates of dust fallout and creeping sands, and prevalence of wide intertidal flats) and specific problems in the sewage works (high strength and anaerobicity of sewage, lack of alternative routes from peripheral pumping stations to a central treatment plant that is biochemically overloaded, emergency discharge through short outfalls onto wide intertidal flats, and discharges from premises that are not connected to a sewerage scheme). Recommendations to alleviate these impacts are summarized.