bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of the fixation of several metal ions onto a low-cost biopolymer
Authors: Reddad Z. , Gérente C. , Andrès Y. , Le Cloirec P. 
Published: May 2018

In the present work, sugar beet pulp, a common waste from the sugar refining industry, was studied in the removal of metal ions from aqueous solutions. The ability of this cheap biopolymer to sorb several metals namely Pb2+, Cu2+, Zn2+, Cd2+ and Ni2+ in aqueous solutions was investigated. The metal fixation capacities of the sorbent were determined according to operating conditions and the fixation mechanisms were identified. The biopolymer has shown high elimination rates and interesting metal fixation capacities. A pseudo-second-order kinetic model was tested to investigate the adsorption mechanisms. The kinetic parameters of the model were calculated and discussed. For 8 × 10-4 M initial metal concentration, the initial sorption rates (v0) ranged from 0.063 mmol.g-1.min-1 for Pb2+ to 0.275 mmol.g-1.min-1 for Ni2+ ions, with the order: Ni2+ &gt; Cd2+ &gt; Zn2+ &gt; Cu2+ &gt; Pb2+. The equilibrium data fitted well with the Langmuir model and showed the following affinity order of the material: Pb2+ &gt; Cu2+ &gt; Zn2+ &gt; Cd2+ &gt; Ni2+. Then, the kinetic and equilibrium parameters calculated qm and v0 were tentatively correlated to the properties of the metals.
Finally, equilibrium experiments in multimetallic systems were performed to study the competition of the fixation of Pb2+, Zn2+ and Ni2+ cations. In all cases, the metal fixation onto the biopolymer was found to be favourable in multicomponent systems. Based on these results, it is demonstrated that this biosorbent represents a low-cost solution for the treatment of metal-polluted wastewaters.
Wastewater reuse and treatment options for the dairy industry
Authors: Baskaran K. , Palmowski L.M. , Watson B.M. 
Published: May 2018

Milk-processing plants generate significant quantities of wastewater with relatively high organic matter concentrations on a daily basis. In addition to environmental damage that can result from the discharge of these wastewaters into the natural waterways, the presence of products such as milk solids into wastewater streams represents a loss of valuable product for the plants. This paper presents a review of wastewater management practices employed by six milk-processing plants in Victoria, Australia. In all six plants investigated, milk powder represents a major product. During the milk powder production, water is evaporated, condensed and can be reused for various purposes with a significant impact on water usage. Other major products are anhydrous milk fat, cheese, butter, and UHT milk.
The effectiveness of the practices was assessed through two main criteria: first through the water to milk intake ratio, and the waste volume coefficient. Both parameters characterise the plant efficiency in regard of water consumption and water reuse. Information on cleaning chemical usage and recovery was also assessed as part of the review. Significant discrepancies emerge between the plants first due to the products manufactured and water reuse possibilities available in each plant. Second the type of treatment technologies used for condensate and cleaning solution influences the figures. One of the investigated plants is almost self-sufficient for water, emphasising the benefits gained from the use of technologies like membrane separations for condensate and cleaning solution treatment. In some cases, less cost-intensive technologies such as a clarifier are successful to improve cleaning agent recovery.
Aggressive flushing for discolouration event mitigation in water distribution networks
Authors: Boxall J.B. , Skipworth P.J. , Saul A.J. 
Published: May 2018

Discolouration is one of the biggest causes of customer complaint associated with potable water. The flushing of systems has been widely identified as an appropriate pro-active means of removing material from distribution networks and hence controlling discolouration. Such flushing involves creating aggressive hydraulic forces within the network such that the materials that contribute to discolouration are mobilised and removed. Understanding of the causes and mechanisms leading to discolouration are poor. Previous work has been presented on the characterisation of material and particles collected at hydrants during flushing trials in the UK. From this data it was hypothesised that the materials causing discolouration originated from cohesive layers on pipe walls, and that once disturbed the material is maintained as a permanent suspension even under the most quiescent of networks conditions. The work presented in this paper attempts to validate the hypothesis that the discolouration materials originate from cohesive layers, and investigate the nature and variability of such layers within live distribution systems.
The study involved the aggressive flushing of a long discrete length of cast iron pipe with known discolouration problems. The results showed a progressive generation of material over the length of the pipe, confirming that the material originated from a uniformly distributed cohesive source. This was followed by a sequence of flushing operations for the systematic cleaning of a complex network area, encompassing a mixture of pipe materials and ages. All measured turbidity traces showed exponential decay with time. Such exponential decay may be predicted by a model based on a change in layer strength with degree of erosion. Hydraulic forces appear to be a key factor governing the availability and mobilisation of material. Iron is the dominant material mobilised from all the pipes. There is no direct trend between the amount or the composition of the material mobilised from the different pipes.
Dependency of bulk chlorine decay rates on flow velocity in water distribution networks
Authors: Menaia J. , Coelho S.T. , Lopes A. , Fonte E. , Palma J. 
Published: May 2018

Understanding chlorine residual decay kinetics and the factors that influence them are essential for such current tasks as siting chlorination facilities, dosage optimisation, choice of sampling locations and frequencies, and general design and operational control of drinking water networks, increasingly accomplished with the help of simulation models.
Available constants for bulk chlorine decay are typically determined under static conditions. However, as for all fast reactions in water flows, chlorine consumption rates in drinking water pipes may be influenced by the existing mixing regimes, a function of flow turbulence, which is primarily controlled by flow velocity and pipe diameter.
Flow velocities vary greatly in space and time in water transmission and distribution systems; pipe diameters are seldom uniform. Although both variables are readily available in the currently available network analysis simulators that implement chlorine models, such variations are not accounted for. Instead, a single preset decay rate constant is generally used for describing chlorine residual consumption throughout an entire system.
In addition to highlighting how negligible PVC pipe wall chlorine consumption is, as such, this paper presents experimental evidence of a significant correlation between pipe flow velocity and bulk chlorine decay rates, and proposes a simple but effective approach to implement this dependency in current simulators.
Saragossa, 50 examples of efficient water use in the city
Authors: Viñuales Edo V. , Fernández Soler M. 
Published: May 2018

The water saving project, Saragossa, water saving city. 50 Good Practices aims to resolve the problems of water scarcity with a different approach which is cheaper, more ecological and free from social conflicts: increasing the efficiency of its use. It seeks to provide a model to be imitated by the more than 9,000 Spanish towns which waste over 1,500 hm3 of water per year.
In 1997 a collective challenge was put forward: to save 1 billion litres of water in one year. In fact 1,176 billion litres was saved, 5.6% of domestic consumption. 50 Good Practices in efficient water use are currently being worked on. As we have demonstrated in the project, technological change is produced via imitation. The Hospital Royo Villanova, with a consumption of 382 litres per bed per day, is one such example to imitate; this is one of the best ratios in the world. Today Saragossa has one of the lowest ratios of domestic consumption per inhabitant per day in Spain: 96 litres.
Integrated operation of drinking water treatment plant at Amsterdam water supply
Authors: Bosklopper Th.G.J. , Rietveld L.C. , Babuska R. , Smaal B. , Timmer J. 
Published: May 2018

Water treatment plants are in general robust and designs are based on the performance of individual processes with pre-set boundary conditions. It is assumed that an integral approach of the entire treatment plant can lead to more efficient operation. Taking into account the developments in sensoring, automation and computation, it is a challenge to improve quality and reliability of the treatment plants and to make maximal use of the installed infrastructure, postponing new investments.
At Amsterdam Water Supply (AWS), the first steps have been taken to come to an integral dynamic model of the total water treatment plant and the use of this model as an instrument for integral control. The parameters influencing the performance of the water treatment process will be incorporated in an overall model evaluating the goal factors quality (good, constant and reliable), quantity, costs, environmental impact (low residuals level), redundancy and flexibility. For several individual processes at AWS models have already been developed during the last few years, like models for the ozone process, biological activated carbon filtration and pellet softening. For the final calibration and validation pilot reactors are automated and on-line data are collected. Criteria for evaluation are developed to realise an optimal control of the individual processes in interaction with the goal factors of the total treatment process.
Reliability of valves and section isolation
Authors: Trietsch E.A. , Vreeburg J.H.G. 
Published: May 2018

Section valves are essential for isolating incidents such as pipe bursts. In older networks where incidents occur most, valves have aged and their reliability has decreased. In addition, design rules or guidelines to locate valves in a network to ensure continuity of supply and to minimize effects on customers are generally lacking, as was concluded at an international workshop on valves in 2001.
Within the framework of the joint research programme of the Dutch water companies a methodology has been developed to translate the reliability of individual valves or clusters of valves into the reliability of supply for one or more sections in a network. The reliability of a section is characterised by performance indicators such as Customer Minutes Lost (CML): the average time in a year that a connection is without water due to an incident in the network. The methodology enables water companies to set priorities within their valve maintenance strategy, based on critical performance indicators, costs and maintenance frequency.
The methodology was translated into software and applied to a case study of the Dune Water Company of South Holland. The case study proved that the methodology and the software work well. Specific changes such as (re)location and enhancing the reliability of valves improve the performance and reliability of the network. As it is an emergency provision, investments can be done at ‘natural’ rehabilitation moments.
Ocean Dumping of Sludge vs. the Alternatives
Authors: Bogert I L , Sokol L J 
Published: May 2018

Studies have been conducted in the East Coast Region of the United States challenging USEPA's determination that municipal sewage sludge dumpers fail to meet ocean dumping criteria.
Laboratory testing of liquid phase and bioassay and bioaccumulation of the Bergen County (New Jersey) Utilities Authority's digested sludge has been performed. The results indicated that the digested sludge falls within the required criteria and would not cause an adverse harmful effect on the marine environment. Inherent in the EPA's interpretation of the law is that other land-based alternatives to ocean dumping are not only feasible, but offer less relative environmental risks. The case against E PA's interpretation is increasingly apparent from studies indicating more severe risks from land-based alternatives.
Sludge Disposal to Sea in the Federal Republic of Germany†
Authors: Fuchs D 
Published: May 2018

Sludge disposal to sea in Germany is on the one hand dependent on the quantities requiring disposal, the handling methods and treatment processes used. On the other hand the regulations for waste disposal to sea in Germany must be observed and the priority given to landbased methods. In addition the national authorities in issuing a permit have to take into account existing scientific knowledge and exercise judgement. It is firmly intended to terminate sludge disposal to sea completely and sewage sludge has to meet the requirements for its use in agriculture.
†This paper should be included in Theme 3 - Case Histories.
Education and Training of Operators in the Federal Republic of Germany
Authors: Pluemer C H 
Published: May 2018

Treatment works are becoming high grade installations requiring sophisticated operation and maintenance. Production of well educated and trained operators is required if one is to avoid economic losses and damage.
In the Fed.Rep. of Germany three grades of operators are trained:
Klärwärter
Klärfacharbeiter
Klärmeister
The training includes experience in the field, lectures and examinations. Each grade needs a certain time of experience at a treatment plant. In neighbourhoods further training is offered. Highly trained staff have their own workships, seminars and congresses to exchange knowledge.
Surface Dilution of Round Negative Buoyant Jets–A Comparison with Other Jets
Authors: Noutsopoulos G , Demetriou J 
Published: May 2018

Experimental results, concerning surface dilutions of round turbulent jets with negative buoyancy, are presented and discussed. Fresh water jets, of density ρo, discharging from a vertical pipe, of internal diameter do, placed in the middle of the experimental tank, at a depth H from the free surface of a quiescent ambient liquid, consisting of common salt water solution, of density ρs, slightly larger than ρo, have been studied.
Dilution measurements, made with a conductivity probe, have been performed, along radial traverses, at a small depth of 5do, below the free surface. The experimental results were analyzed and presented in terms of dimensionless dilution scale gl versus the dimensionless length scale zl. In this form they are directly compared to axial dilution results of the positive buoyant jet. With the proper definition of length scale, they are expressed satisfactorily by the well established semiem-pirical expressions, concerning the axial dilution of positive buoyant jets. Semiem-pirical relationships, concerning the axial dilution distribution of the horizontal buoyant jet, are also presented. Thus, a direct comparison is made possible for surface dilutions in the three round buoyant jet cases, namely the positive, the negative and the horizontal jet, which will be very useful in engineering design.
Obtaining Secondary Treatment with RBC/Underflow Clarifiers
Authors: Bogert I L 
Published: May 2018

A one-year experimental program conducted at Edgewater, New Jersey, U.S.A. evaluated the concept of providing secondary treatment by the installation of rotating biological contactors (RBC's) in modified primary sedimentation tanks.
A primary tank was divided horizontally into two zones separated by an intermediate floor. Four RBC's were placed in the upper zone. The lower zone provided secondary sedimentation. High rate primary sedimentation was provided to remove grit and trash without removing substantial portions of BOD and SS.
The experimental program funded by the U.S. EPA and the Borough of Edgewater was conducted over a full year at different loads. The system proved to be an effective secondary treatment process with little difference in treatment efficiency between summer and winter conditions.
Leaching Characteristics of Industrial Metal Finishing Wastewater Treatment Plant Solids
Authors: Goodgame T H , Barnett P W 
Published: May 2018

The safe disposal of industrial wastes is an international problem of increasing magnitude. There are very limited disposal sites for wastes which are hazardous in nature. The purpose of this study was to determine the leaching characteristics of solids resulting from the treatment for discharge of wastewaters produced by typical large metal finishing facilities.
Samples were chosen so that the full range of both manufacturing processes and products produced were covered. The primary processes which contributed to the wastewater for treatment were “phosphating” in preparation for organic coating and “pickling” in preparation for application of porcelain enamel.
These samples, along with a sandy loam soil as a control, were placed in lysi-meters. Distilled water was used as the leaching liquid, as being most representative of landfill conditions. Liquid was passed through the samples at the rate of one liter per week. Based upon the area of the lysimeter this rate was equivalent to a percolation rate of 510 cm per year. Leachate samples were analyzed for twenty-two different parameters: pH, TSS, COD, alkalinity, chloride, nitrate, phosphate, sulfate. Al, B, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Na, Ni, Pb, Ti and Zn.
The results of these tests indicate that the WWTP solids act very similarly to the soil used as a control. The leachate concentrations of heavy metals and the depletion of the heavy metals were such that this material would create no problems if disposed in an ordinary landfill – indicating that it is neither toxic nor hazardous. The time frame of this experiment was equivalent to ten years exposure in an ordinary landfill, and to a much longer period if deposited in a sanitary landfill.
Review of Water Pollution Problems and Control Strategies in the South African Mining Industry
Authors: Kempe J O 
Published: May 2018

Water resources in South Africa are limited. It is inevitable that in a climate of expanding industry and economy, total salt loads discharged both from point and non-point sources will increase. The effect of this on these resources will soon assume crisis proportions unless effective treatment for the removal of salt loads from effluents is exercised and rigid constraints imposed on effluents not conforming to prescribed quality standards.
The mining industry is a large user of water and a major contributor to salt load entering streams, rivers and encatchments. Special attention is given to the use of water and discharge of effluents by this large and important industry.
The Handling and Disposal of Coal Ash in the Cegb in Relation to the Aqueous Environment
Authors: Brown J , Ray N J 
Published: May 2018

Pulverised fuel ash (pfa) and furnace bottom ash (fba) are the principal solid wastes from modern coal fired plant. These residues are often handled and disposed of as slurries and pfa is frequently used for the reclamation of derelict land.
The disposal of excess water from the handling operation after the ash has been allowed to settle in a pond or lagoon is the first interaction with the aqueous environment that needs to be considered. In CEGB, the discharge of such effluents to rivers is governed by consents laid down by Water Authorities. The state of the art is such that the required conditions can be met in once-through handling systems without undue difficulty but one factor which requires careful management is the level of suspended solids in the outfall when a lagoon is nearly full.
Whether ash is disposed of wet, or merely conditioned with water to facilitate handling. there may be a further need to consider the percolation of water through the ash and its possible interaction with groundwater. This calls for knowledge or study of the ash itself, the size of the area to be reclaimed, the rainfall pattern and the local hydrogeology, including the size and rate of recharge of the aquifer. Each case needs to be considered on its merits. The basic CEGB approach to this aspect of ash disposal is discussed; it requires the combination of laboratory studies of percolate quality with hydrogeological assessment to evaluate the potential risk, if any. The actual consent to dispose of ash, taking such factors into account, is made by the Local Authority in consultation with the Water Authority.
The present view of ash disposal relative to the aqueous environment could be disturbed if legislation and the associated Codes of Practice were to become more stringent. Recent control measures which are pertinent to these activities are, therefore, considered and comment made on their content and application.
Comparison of Different Methods for Estimating the Leaching of Heavy Metals from Coal Combustion Waste
Authors: Reuss Merete 
Published: May 2018

Literature on the different leaching methods for estimating the heavy metal content in coal fly ash was studied and is herein summarized. Attention is given to some of the practical problems which must be addressed in planning a leaching test.
Strong acid digestion and several methods for the determination of total metal concentration are discussed. Results of leaching experiments with 6 different fly ashes are reported. Ag, As, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Se, V, Zn, Na, K, Ca, and Mg were determined. These same metals were determined by atomic absorption spectrophotometry after both nitric acid and hydrofluoric acid digestion. The two digestion methods are compared.
Volatile Compounds of the Cyanophyceae – A Review
Authors: Slater George P , Blok Vivian C 
Published: May 2018

A relationship between blue-green algae and off-flavours in water was reported as early as 1883. Continuing research has shown that two metabolites, geosmin and methylisoborneol are major contributors to unpalatable flavours in water and aquatic organisms. Many instances of the co-occurrence of these two compounds and dense blooms of blue-green algae have been recorded. Cultures of Anabaena, Lyngbya, Osciiiatoria, and Sympioca species have been shown to produce geosmin or methylisoborneol while blooms of Aphanizomenon, Anabaena, Microcystis, Oscillatoria, and Gomphosphaeria have been found in water containing geosmin or the odour of this compound. Actinomycetes have also been shown to produce these two compounds.
In addition to geosmin and methylisoborneol, there is evidence that several other blue-green algal metabolites contribute to aquatic taste and odour problems. Among them is β-cyclocitral which has a distinctive tobacco flavour. Blue-green algae produce a variety of organic compounds including hydrocarbons, fatty acids, aromatics, ketones, terpenoids, amines and Sulfides which could contribute to the over-all flavour of water and aquatic organisms.