bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Fouling Potential for Pressure-Driven Membrane Processes: A New Simulated Flow Cell
Authors: Reed R H , Belfort G 
Published: May 2018

Membrane systems are unit processes that are becoming widely accepted for the demineralization of saline and other waste waters. Dissolved and particulate material, specifically colloidal matter, present in the feed stream to membrane systems are considered the principal causes of membrane fouling and reduced efficiency. Conventional water analysis do not yield the information needed to determine the amount of fouling that will occur. Therefore, some rapid indication of the water quality and its potential to foul is needed.
Presently there are five tests available to evaluate feed-water quality for membrane processes. However, in each of these tests the apparatuses used do not model tangential (shear) flow across the membrane surface. Therefore, a new apparatus was designed and constructed to predict how the feed water foulants would behave in a flow field.
A new apparatus, named the Simulated Flow Cell (SFC), was developed and tested in the laboratory with feed waters containing polystyrene latex spheres (PSL) as foulants and in the field with well-water and precholorinated secondary effluent. The SFC reproduced essentially the same results as the standard non-flow cell when operated under the same conditions. However, the SFC was also able to model flow regimes to membrane systems.
The Simulated Flow Cell was tested using irradiated polycarbonate membranes with pore diameters ranging from 0.1 µm to 1.0 µm. The feed water turbidity was varied during the testing by the addition of PSL spheres. Varying these parameters permitted data collection under a wide range of conditions. For laboratory feed water with the addition of PSL spheres, a theoretically expected threshold velocity was observed with the SFC using 0.1 µm pore diameter membranes. The threshold axial velocity was directly proportional to the square root of the initial flux through the 0.1 µm Nuclepore membranes, which is in agreement with data collected from actual hyperfiltration plant operations.
The Simulated Flow Cell is a low cost apparatus for the rapid characterization of permeator feed waters. The Simulated Flow Cell promises to become an important tool in the ever widening use of membrane processes in water and wastewater applications.
A Mathematical Model of Biological Purification in Aerated Activated Carbon Biofilters
Authors: Martin G , Le Roux A-Y , Schulhof P 
Published: May 2018

On the basis of results obtained in the laboratory and in a semi-industrial pilot, this paper outlines the probable mechanism of biological purification on activated carbon. It shows that with small loads, the medium's porosity plays a permanent role in the treatment of a water. The biological activity which develops on the material acts in a complementary fashion, allowing for continuous regeneration of the activated carbon's pores.
With heavy loads, there are two phases. During the first, adsorption and biological regeneration are complementary. This phase lasts three to four hours. During the second phase, development of the biomass obstructs the occurrence of the adsorption phenomenon.
Substrate is removed on the surface. This second phase lasts from fifteen to twenty hours, until the filter is clogged. After washing, the first phase again enters into operation.
A mathematical model is presented. It describes results obtained with small and heavy loads.
Granular Activated Carbon and Preozonated Granular Activated Carbon Treatment for Biologically and Physically-Chemically Treated Wastewater Effluents
Authors: Netzer A , McNutt J L 
Published: May 2018

The Duck Creek Wastewater Treatment Plant is a combined municipal-industrial wastewater treatment facility serving a municipal population of over 200,000 and an industrial community of over 600 various light industries. This 30 MGD treatment facility operates in a split-stream mode, with 7.5 MGD treated by biological processes and 22.5 MGD treated by physical-chemical processes. Final treatment for both systems is supposed to consist of granular activated carbon treatment and chlorine disinfection.
Problems in operation and implementation of the granular activated carbon systems for the combined biological and physical-chemical treatment effluents prompted The University of Texas at Dallas to design and construct a pilot plant facility composed of 5 pilot plant systems. This facility provides for evaluation of granular activated carbon (GAC) treatment and preozonated granular activated carbon (POGAC) treatment for biologically, physically-chemically, and blended (biologically and physically-chemically) treated wastewater effluents simultaneously. The UTD-Duck Creek Pilot Plant Facility has been operating since November, 1979, demonstrating the improved operation and treatment efficiency of preozonated granular activated carbon treatment for biologically, physically-chemically, and blended wastewater effluents.
In addition to improved treatment efficiency demonstrated by the preozonated granular activated carbon systems, average operational life prior to bed exhaustion was extended from an average 70 days for GAC to over 300 operational days for POGAC.
The Adsorption Behaviour of Cationic Polyelectrolytes in Dissolved Air Flotation
Authors: Gehr R , Henry J G 
Published: May 2018

This study examines the adsorption behaviour of polymers of various molecular weights (MW) in dissolved air flotation (DAF) systems. Batch and full scale DAF tests were done using activated sludge. Residual polymer was measured by a titri-metric method, and Zeta potential (ZP) measurements of the effluent were also made. Two highly charged cationic polyelectrolytes of different MW were used.
In batch tests, the two polymers yielded similar performance in terms of effluent and float solids concentrations, but slightly less high MW polymer was needed to attain low effluent SS. In both cases, polymer residual was detectable only when polymer doses beyond that needed for lowest effluent SS were applied. Significant increases in float solids concentration also occurred only at the higher doses. Polymer adsorption followed the Langmuir isotherm behaviour. Higher MW polymer adsorbed in larger quantity, indicating that the polymer “monolayer” was not flat on the surface of the sludge particles. ZP reversal (to a positive value) occurred only when polymer residual was detected, not at the polymer dose required for lowest effluent SS. Results were confirmed with full scale tests.
A model for polymer-induced flocculation is presented, suggesting that polymer attachment occurs by attraction of opposite charges, but that bridging of colloids occurs to cause incorporation in the float. It is indicated that the cationic condition in the float at excess polymer dose causes exclusion of water in favour of air bubbles, and hence a more concentrated float.
Thermal Discharge and Fish Fauna in Sweden
Authors: Neuman Erik 
Published: May 2018

Investigations on the fish fauna have been performed at four thermal power plants in Sweden situated on Lake Mälaren, the Baltic, the Sound and the Kattegatt. The results illustrate effects of thermal discharge in various salinities, from fresh water to above 20‰. The presentation is based on material from several years of test fishing with gill nets and fyke nets.
The most common species have been classified as warm- or cold-water fishes on the basis of the catch/temperature relationship. The reactions towards the cooling-water mainly correspond to this grouping. Exceptions due to special hydrographic conditions and to the supply of food are discussed.
Shallow bottoms in freshwaters and at the Baltic coast are massively dominated by warm-water species of freshwater origin, while marine cold-water fishes hold a strong position in the higher salinities of the Sound and the coast of the Kattegatt. The effects of thermal discharge upon the species composition are thus demonstrated to increase with the salinity.
Modelling the Consequence of Cooling Water Discharge from the “Vendsyssel” Power Plant
Authors: Malmgren-Hansen Anders , Dahl-Madsen K I 
Published: May 2018

Discharge of cooling water from power plants has various effects on the ecosystem in coastal areas. The effect on primary production due to the rise in temperature in the outlet area and the decimation of zooplankton organisms passing through the cooling system of the power plant can be calculated by means of mathematical models.
Calculations of the consequences of a considerable increase in cooling water discharge from the “Vendsyssel” power plant are presented.
The decimation of zooplankton is calculated by means of a combined 2-dimensional hydraulic and zooplankton-growth model.
Calculations of the effects on primary production are carried out by use of a combined 1-dimensional hydraulic and eutrophication model.
Transport of Airborne Mercury Emitted by Coal Burning into Aquatic Systems
Authors: Brosset Cyrill 
Published: May 2018

Concentrations of watersoluble and insoluble mercury compounds in air, precipitation and smoke from coal combustion have been measured.
It has been found that in western Sweden 10-20% of airborne mercury is in an oxidised watersoluble form. The corresponding figure from one boiler is ~70%.
Full Scale Experiences with the Phostrip Process
Authors: Peirano Lawrence E , Henderson Douglas B , Gonzales John G M , Davis Eugene F 
Published: May 2018

The PhoStrip process is a biological-chemical process which removes phosphorus from wastewater.
This article presents descriptions of the PhoStrip process, a plant-scale test of the process, the design of a 152,000 m3/d PhoStrip facility, and the start-up and initial full scale operation of the PhoStrip facility, all in association with the expansion of the Reno-Sparks Joint Water Pollution Control Plant in Nevada, USA.
The PhoStrip process has demonstrated the capability of removing phosphorus to effluent levels of less than 0.5 mg/l at operating costs much less than operating costs associated with conventional chemical processes.
Fluidized Bed Biofilm Reactor (FBBR)Kinetics – A Rational Design and Optimization Approach
Authors: Shieh Wen K , Mulcahy Leo T 
Published: May 2018

A mathematical model is presented for an intrinsic zero order, completely mixed fLuidized bed biofilm reactor(FBBR). Intrabiofilm mass transfer effects are considered. A modified Thiele modulus(ϕm) is defined to relate substrate conversion rate to intrabiofilm mass transfer rate through use of an effectiveness factor(η). For ϕm− &lt; 1.15, intrabiofilm mass transfer is insignificant and intrinsic zero order kinetics is observed. For ϕm &gt; 1.15, the FBBR substrate conversion rate is mass transfer limited and 0.45 order kinetics is observed.
It is demonstrated via the FBBR model that media size and density and biofilm thickness are the most significant design parameters affecting FBBR performance. Selection of these parameters can be optimized through use of the equations presented herein. In addition, the effect of other important design parameters such as recycle rate and superficial upflow velocity on reactor performance can be assessed using the FBBR model outlined here.
Sludge Thickening Prior to Anaerobic Digestion
Authors: Kapp H 
Published: May 2018

In the Federal Republic of Germany the average solids content in digested sludges is about 3%. Increasing the solids content to 6-8% by pre-dewatering would mean that the sludge volume would be reduced to 40-50%. For the same retention period the volume of new digesters will be reduced and the necessary energy for heating decreased. Overloaded sludge treatment plants can be upgraded, as digestion time becomes longer and gas production increases.
As pre-dewatering machines, first of all decanting centrifuges and screens can be recommended. The addition of coagulant aids is necessary to some extent.
In the case of two practical examples, the operating parameters of raw sludge thickening as well as the economic advantages of the operating procedure are shown.
Environmental Consequences of a Large Scale Coastal Engineering Project on Aspects of Mussel Cultivation in the Eastern Scheldt
Authors: Misdorp R , Kohsiek L H M , Steyaert F H I M , Dijkema R 
Published: May 2018

The rewatering location in the Eastern Scheldt at Yerseke has an important function for the Dutch mussel culture, safeguarding the keeping quality of the mussels. The mussels are relaid during 2–4 weeks on rewatering plots between production and marketing. It was feared that, after completion of the Storm-Surge Barrier in the Eastern Scheldt, the rewatering function would deteriorate as a consequence of accumulation of mussel-deposited mud (pseudo-faeces) and a decline of water quality during periods of low current velocity. A research program was drafted in order to make a prognostication of sedimentation and erosion and of the occurrence of adverse water quality and food shortage on the plots after the completion of the Storm-Surge Barrier.
A study was made of erosion factors such as tidal currents, wave action and periodical dredging of mussels on the plots. Besides, food content and water quality parameters were measured. The measurements were carried out during 13-hours periods at half-hourly intervals. Periodic dredging of mussels on the plots appeared to be the most important among the erosion forces, while tidal currents and wave action have less impact.
Sedimentation is almost entirely caused by the filtering activity and deposition of faeces by the mussels. It is expected that after the completion of the Storm-Surge Barrier the erosion forces will decrease slightly.
Whether the erosion and sedimentation balance on the rewatering location, presently more or less in equilibrium, will change, will mainly depend on the future rate of faeces production. This, however, is difficult to predict.
Water Quality Aspects of the Nakdong Estuary Barrage
Authors: van Sluis J W , Lijklema L 
Published: May 2018

As a result of the construction of a barrage in the estuary of the Nakdong river the size of the estuary will be considerably reduced. In addition, a large river reservoir is created upstream of the barrage.
Main points of interest are the effects of the discharge of raw sewage and treated effluent into the Nakdong river on the water quality in the projected reservoir and the water quality forecasts for the remaining part of the estuary, in relation with the existing plans for sewerage and sewage treatment for the city of Busan. In addition, measures to reduce the effects of the barrage and the outline of a water quality management programme are presented.
Special consideration is given to the methodological aspects of the water quality study, i.e. the selection and use of mathematical models in a situation where input data are rather uncertain and only very few data for parameter estimation and model verification are available.
The Hard Bottom Biocoenoses and the Fish Fauna of Lake Grevelingen, and Their Reactions to Changes in the Aquatic Environment
Authors: Waardenburg H W , Meijer A J M , Phillipart R J L , van Beek A C 
Published: May 2018

In 1970 the Biological Working Group of the Dutch Underwatersports Association started an investigation of the hardbottom biocoenoses in the Grevelingen. Since 1979 we extended the investigation and since 1980 a monitoring investigation of the fish fauna in Lake Grevelingen has also been carried out. The aims of the investigations are to gain insight into the presence and coverage of the hard bottom biocoenoses and their reactions to changes in the aquatic environment, as well as to gain a continuous up-to-date insight into the presence of the various fish species, so that (management) measures can be advised.
In this paper, the results obtained in the period 1970 to 1983 are given. The authors recommend opening the sluice in the Brouwersdam for much longer periods and carrying out an active management using this sluice and the siphon sluice in the Grevelingendam, which can be put into use at the end of 1983.
Relating Effluent Control Parameters to River Quality Objectives Using a Generalised Catchment Simulation Model
Authors: Bowden K , Brown S R 
Published: May 2018

A computer model has been developed which combines a simulation based approach with the modular logic of the steady-state catchment approach, and provides facilities for calibration and verification of simulated data against observed data. Temporal correlation of simulated variables (e.g. flow and concentration) is also possible.
This model has been used to study the River Wey basin with a view to assessing the impact of twelve significant sewage effluent discharges upon the river, to identify where action is needed to restore and maintain the quality of the River Wey and its tributaries, and to seek a solution combining the various options of revising sewage works' operating targets and making improvements to works' performance.
This study having been completed, the preferred options have been identified and are being put forward for discussion within the Authority.
The Two-Step Nitrification of Ammonia-Rich Waste Water
Authors: Pascik Imre , Mann Theo 
Published: May 2018

In a refinery, pilot plant studies have been carried out for the nitrification of waste water containing 700 to 900 mg/l ammonia. The aim was to work out a treatment concept that could be used to build a full scale plant for nitrogen elimination by nitrification and denitrification.
The optimal treatment method found was the two-step nitrification method, where−the first step (high NH4+-load) results in a BOD-elimination and a partial nitrification (60 to 85% of the NH4+-load), and−the second step (low NH4+-load) results in an oxidation of the remaining NH4+-oxidation down to 10-25 mg/l NH4+.
By this process the aeration volume required for the nitrification was reduced by approximately 40%. The full-scale plant designed for the elimination of 8 000 kg NH4+ per day started operation in July 1981.
Process Control in Anaerobic Wastewater Treatment
Authors: Frosteil Björn 
Published: May 2018

The monitoring and control of anaerobic waste water treatment is discussed. In a first section optimum biological conditions were given. These are a nutritionally balanced waste water free from oxidants and toxicants, a temperature of 55-60 °C and a pH of 6.8-8.0.
In a second section, parameters for monitoring and control were discussed. It was concluded that present system designs usually allow for the control of influent flow rate and temperature but not for the key parameter solids retention time (SRT). Process control in anaerobic waste water treatment, therefore, is more monitoring than control, a situation that is unsatisfactory.
The Role of Facultative Anaerobic Micro-Organisms in Anaerobic Biodegradation of Chlorophenols
Authors: Hakulinen R , Woods S , Ferguson J , Benjamin M 
Published: May 2018

Pure cultures of facultative anaerobic bacteria and yeasts were isolated from anaerobic reactors fed synthetic wastewater which contained eight different chlorophenolic compounds. The concentration of facultative anaerobic micro-organisms was followed in the reactor throughout the experimental period, during which the chlorophenol concentrations were increased and many of the chloronated phenols were removed nearly completely.
The most common species were Klebsiella spp. and K. Pneumoniae. Some of the common colonies were tentatively identified as Pseudomonas-like organisms and Aeromonas hydrofila. Methanogenic bacteria in the reactor were mainly acetate users. When the total chlorophenol concentration in the feed was increased from zero to 2.4 or 5.3 mg/1, the concentration of Pseudomonas-like organisms increased, as did the concentration of yeasts.
Pure and mixed cultures were tested for use of 2,4,6-trichlorophenol (246-TCP) as a sole carbon and energy source under anaerobic conditions. None of the isolates were able to degrade 246-TCP under anaerobic conditions in pure culture. However, mixed cultures containing only P. aeruginosa and K. oxytoca were able to degrade 246-TCP.
Sludge Characteristics in Uasb-Reactor Treating Thermomechanical Pulping Effluents
Authors: Vuoriranta P J , Rintala J A , Kirjavainen H 
Published: May 2018

Sludge from laboratory scale UASB-reactors under various operating conditions and sulfur concentrations was characterized by using electron microscopy and microbiological methods.
The objective of this research was to evaluate factors effecting sludge granulation and the relationship between sludge morphology and sludge activity, measured as a function of biogas production.
Detection of Enteroviruses: An Assessment of Ten Cell Lines
Authors: Morris R. 
Published: May 2018

The routine monitoring of waters and wastewaters using the BGM - suspended cell plaque assay system has resulted in high isolation rates for polio and coxsackie B viruses with echoviruses only rarely being detected.
Ten cell lines (five of human origin, five of simian derivation) were examined for their susceptibility to twenty six enteroviruses and their ability to isolate naturally occurring enteroviruses in wastewater effluent determined.
All the viruses produced cytopathic effect in the simian cell lines but only in the FL amnion line of human cells. The detection of naturally occurring enteroviruses was most efficient when BGM cells were used with 82% of samples being positive. RD cells gave 73% positive whilst chimpanzee liver gave 64%. However, the number of plaques formed in the presence of each cell line showed that BGM detected 50% of all plaques observed with RD and chimpanzee liver detecting 21% and 9% respectively. The serotypes detected in this study were of the polio and coxsackie B groups, no echoviruses being identified.
Use of Peracetic Acid in Operational Sewage Sludge Disposal to Pasture
Authors: Fraser J A. L. , Godfree A. F. , Jones F. 
Published: May 2018

Intestinal pathogens and parasites are a problem associated with the disposal of sewage sludge to pasture. Those of major importance are ova of the beef tapeworm (Taenia saginata) and Salmonella bacteria. Techniques for routine monitoring of pathogens and intestinal parasite levels in sludge together with design of simple methods for their removal have intensified, because disposal of sewage sludge to pasture is coming under increasing international surveillance.
The performance during field trials of a proprietary peracetic acid compound (containing 36 to 40% w/w peracetic acid), hereafter referred to as PAA (100%), is described. These trials under operational conditions showed it to be a suitable bacterial and ovicidal agent for the disinfection of raw, digested and activated sludges.
Concentrations ranging from 250 to 1000 mg PAA/l have achieved up to 99% inhibition of hatching and up to 100% destruction in viability of tapeworm embryos suspended in raw and digested sludges.
Similarly these concentrations resulted in 5 log reductions in salmonellae seeded in raw sludge. A dose of 250 mg PAA/1 reduced salmonellae levels from 4600 organism/100cm3 to &lt;30/100cm3 during gravity thickening of surplus activated sludge. Results from 46 tanker loads of consolidated surplus activated sludge revealed that salmonellae levels were reduced from 2400 organisms/100 cm3 to &lt;30/100 cm3 at doses of 500, 400 and 300 mg PAA/1. At a lower dose of 150 mg PAA/1 levels were reduced to within a range of &lt;30 to 430 organisms/100 cm3.
At optimum disinfection concentrations for the destruction of both bacteria and parasites, PAA was rapidly utilised resulting in safe, readily biodegradable, non-toxic residuals. The technical and practical benefits, principals of disinfecting sludge and ecological safeguards are highlighted in this paper. Use is made of case histories to describe practical operating techniques.