bluuebunny/crossref_metadata_2025 huggingface dataset:
Substrate interactions during aerobic biodegradation of methane, ethene, vinyl chloride and 1,2-dichloroethenes
Authors: Freedman D. L. , Danko A. S. , Verce M. F.
Published: May 2018

Intrinsic biodegradation of trichloroethene and 1,1,1-trichloroethane in groundwater at a Superfund site in California has been observed. An anaerobic zone exists in the area closest to the source location, yielding the expected complement of reductive dechlorination daughter products, including cis-1,2-dichloroethene (cis-DCE) and vinyl chloride (VC). Significant levels of methane and ethene were also generated in the anaerobic zone. The groundwater returns to aerobic conditions downgradient of the source, with methane, ethene, VC, and several other compounds still present. Attenuation of VC in the aerobic zone suggests that it is being biodegraded. In this study microcosms were used to evaluate the role of methane and ethene as primary substrates for aerobic biodegradation of VC. Biodegradation of VC was fastest in the bottles containing ethene, with 40 μmol of VC consumed over a 150 day period, compared to approximately 15–20 μmol with methane or a mixture of methane and ethene. VC did not noticeably inhibit ethene biodegradation but did slow the rate of methane use. Methane inhibited ethene metabolism, which apparently caused a reduction in VC biodegradation when methane was present with ethene. These results suggest that ethene plays an important role during in situ natural attenuation of VC under aerobic conditions. Microcosms were also set up with VC alone. Following a 75 day lag period, VC consumption began and subsequent additions were consumed without a lag, suggesting the presence of organisms capable of using VC as a growth substrate. After providing VC alone for nearly 400 days, aliquots of the enrichment culture were used to evaluate its ability to biodegrade cis- and trans-DCE. Both compounds were readily consumed, although addition of VC as the primary substrate was needed to sustain biodegradation of repeated additions. This result suggests that organisms capable of using VC as a sole substrate may play an active role in aerobic natural attenuation of DCEs.
Novel boom/skirt systems for improvement of water quality in estuarial impoundments subject to saline influx
Authors: Burrows R. , Ali K. H.
Published: May 2018

The recent popularity of esturial barrage construction in the UK has been driven largely by commercial and amenity interests arising from the need to rehabilitate tracts of derelict urban land. Formation of a permanent water body to replace the tidal regime hides unsightly mud banks and facilities ready access for water based recreation. Unfortunately, in most cases, and presumably arising from upstream extreme flood risk assessment, the barrier is designed to overtop under the highest (spring) tidal peaks so allowing a substantial influx of heavier saltwater into the impoundment on a regular basis. This might well substantially exceed influx via any navigational lock operations. The problem created by the salt water is that its greater density causes stratification in the impounded water body. In times of low freshwater flow little mixing takes place and the normal action of the wind, in circulating and aerating the water body, will only extend within the lighter and often thin surface freshwater layer. The consequence is that little reoxygenation of the lower layers takes place leading to depressed dissolved oxygen levels and possible anoxia. Sluice provision in the barrage may be ineffective in expelling the saline layers, so this water remains near stagnant and deteriorates in quality due to sediment oxygen demands until a major fluvial flood, or new saline influx, is able to effectively mix the waters. Conventional continuous surface releases through fish pass and/or by crest overspill ensure the preferential release of the freshwater rather than the problematic saltwater. Retrofitting of novel low cost floating boom/skirt baffle system is proposed here for alleviation of the problem.
Complete remediation of PCE contaminated unsaturated soils by sequential anaerobic-aerobic bioventing
Authors: Mihopoulos P. G. , Suidan M. T. , Sayles G. D.
Published: May 2018

Bioventing principles have been applied to completely dechlorinate tetrachloroethylene vapors in the unsaturated zone in a sequential anaerobic-aerobic pattern. The aerobic step yields trans-DCE and VC as PCE reductive dechlorination byproducts, while TCE and cis-DCE are observed as intermediates. The aerobic step results in rapid oxidation of the VC and trans-DCE to carbon dioxide. Hydrogen was delivered in the gas phase as a reducing agent for the anaerobic step at levels of 1%, and oxygen at 4.2% was used as an electron acceptor in the aerobic step. PCE and VC half lives in the anaerobic and aerobic steps respectively, where less than 10 min.
The influence of fluid shear and AlCl3 on the material properties of Pseudomonas aeruginosa PAO1 and Desulfovibrio sp. EX265 biofilms
Authors: Stoodley P. , Jacobsen A. , Dunsmore B. C. , Purevdorj B. , Wilson S. , Lappin-Scott H. M. , Costerton J. W.
Published: May 2018

An understanding of the material properties of biofilms is important when describing how biofilms physically interact with their environment. In this study, aerobic biofilms of Pseudomonas aeruginosa PAO1 and anaerobic sulfate-reducing bacteria (SRB) biofilms of Desulfovibrio sp. EX265 were grown under different fluid shear stresses (τg) in a chemostat recycle loop. Individual biofilm microcolonies were deformed by varying the fluid wall shear stress (τw). The deformation was quantified in terms of strain (ε), and the relative strength of the biofilms was assessed using an apparent elastic coefficient (Eapp) and residual strain (εr) after three cycles of deformation. Aluminium chloride (AlCl3) was then added to both sets of biofilm and the tests repeated. Biofilms grown under higher shear were more rigid and had a greater yield shear stress than those grown under lower shear. The addition of AlCl3 resulted in a significant increase in Eapp and also increased the yield point. We conclude that the strength of the biofilm is in part dependent on the shear under which the biofilm was grown and that the material properties of the biofilm may be manipulated through cation cross-linking of the extracellular polysaccharide (EPS) slime matrix.
Sustainable development in pollution control and the role of anaerobic treatment
Authors: Lettinga G. , Van Lier J. B. , Van Buuren J. C.L. , Zeeman G..
Published: May 2018

The increasing scarcity of clean water sets the need for appropriate management of available water resources. Particularly regions suffering from a lack of water urgently need integrated environmental protection and resource conservation (EP and RC) technologies in order to enable effective management of the available water resources. EP and RC-concepts focus on pollution prevention and on a minimum of consumptive use of energy, chemicals, and water in pollution abatement and a maximum of re-use of treated wastewater, by-products and residues produced in the treatment of waste and wastewater. Consequently, by implementing these concepts, waste(water)s like sewage and industrial effluents become an important source of water, fertilisers, soil conditioners and (frequently) energy instead of a social threat. In addition, a bridge is made between environmental protection and agriculture practice, stimulating (urban) agriculture in the neighbourhood of large cities.

Anaerobic treatment is considered as the core technology for mineralising organic compounds in waste(water) streams. Additional technologies are required to comply with the reuse criteria. Some examples of possible EP and RC concepts, using the anaerobic treatment technology for the reclamation of domestic sewage are discussed.
Extracellular polymeric substances in relation to nutrient removal from a sequencing batch biofilm reactor
Authors: Choi E. , Yun Z. , Park Y. , Lee H. , Jeong H. , Kim K. , Lee H. , Rho K. , Gil K.
Published: May 2018

Experimental investigations were performed to determine the possibility of simultaneous biological nitrogen and phosphorus removal during various biofilm processes in conjunction with biofilm characterisation, especially extracellular polymeric substance (EPS). Since biological nitrogen removal requires an alternating exposure of anaerobic-anoxic-oxic conditions in the bulk liquid that surrounds the biofilm growth media, a sequencing batch reactor (SBR)-type operation was used. Various materials including expanded clay, polystyrene, polyurethane, and acrylic materials were used as the biofilm growth support medium. Simultaneous nitrogen and phosphorus removal was possible with SBR, but it was postulated that nutrient removal efficiencies varied with film thickness. Thinner biofilm promoted nitrification and phosphorus removal, but thicker biofilm enhanced denitrification and reduced phosphorus removal. EPS contents were similar regardless of support media types or biofilm configuration, but EPS contents gradually increased as the film growth continued after backwashing. EPS contents were increased with increased nitrogen removal, but it was difficult to define its relation with phosphorus removal. In addition, suspended solids removal was correlated well with the EPS content in the biofilms.
Non-point pollution of Ishikari River, Hokkaido, Japan
Authors: Tachibana H. , Yamamoto K. , Yoshizawa K. , Magara Y.
Published: May 2018

We researched the Ishikari river, Japan's second-longest river, to clarify the characteristics of non-point pollution by comparing flux characteristics of chemical components in three periods of one year: the snow melting period, the typhoon flooding period and the stable period. We found non-point pollutants present in great amounts because a large amount of suspended matter, which is contained in soil, flows into the river and concentrations of nutrients and organic matters do not decrease in a short time in the flooding period by rain and in the snow melting period.
LANDFLOW: a 3D finite volume model of combined free and porous flow of water in contaminated land sites
Authors: Das D. B. , Nassehi V.
Published: May 2018

Free and porous flow of water in lands often occurs in combination under different physical circumstances. To model such configurations, open and porous flow regions need to be studied independently and also to integrate them through well-posed mathematical formulations. This paper presents a computational investigation (modelling and simulation) on flow of water and contaminants' mobility in soil. The governing partial differential equations of the flow were discretised and reduced to algebraic forms by finite volume method for simulation purposes. Dirichlet boundary conditions were used at the inlet. For sidewalls, no slip conditions were imposed while for the outer boundary, stress free boundary conditions were used.
Nutrient and suspended solid loads in the Laguna de Bay, Philippines
Authors: Zimmer V. , Bendoricchio G.
Published: May 2018

The Laguna de Bay is the largest lake in the Philippines and is situated 15 km southeast of the centre of Metropolitan Manila. The population of the capital region is growing out of proportion, especially in the watershed area of the lake. This development is endangering the resource Laguna de Bay due to the increasing discharge of nutrient and suspended solid loads from the drainage basin into the lake. During the EU-funded project “Laguna de Bay, Philippines: An Ecosystem Approach for Sustainable Management” a monitoring campaign on selected tributary rivers was conducted. Based on the results of this monitoring and an analysis of census data, the total annual loads were estimated at about 8000 t N, 2300 t P and 160,000 t TSS. The occurrence of the typhoon “Loleng” in the research area during the monitoring campaign made it possible to state that about 25% of the annual load is drained during such a weather situation.
Long term pollution simulation in combined sewer networks
Authors: Masse B. , Zug M. , Tabuchi J. P. , Tisserand B.
Published: May 2018

This paper presents results of long term pollution simulations on the example of the sewerage system of Grand-Couronne. This modelling work is part of a study where objective is to develop a method to define the reference flow of a WWTP. The model HYDROWORKS DM™ has been successfully validated in hydraulics and pollution for the sewer network, for long time simulations. A conceptual model has been built to model the pollution in the tank at the outlet of the combined system. One synthetic year of rain has been used to simulate the working of the “up stream system” of the WWTP (combined sewer + tank + separate sewer + pre-treatments) and has been successfully validated by measurements of the 1998-1999 year. If this paper is focused on the “up stream system”, the SIMBA/SIMBAD WWTP model has been successfully calibrated and validated too, and the combination represents a fully validated “Integrated Model” for the sewerage system.
On-line viable biomass measurement and estimation of the specific growth rate of activated sludge from municipal wastewater treatment
Authors: November E. J. , Van Impe J. F.
Published: May 2018

In order to control wastewater processes, on-line measurements of important process variables are crucial. This contribution focuses on the applicability of the Biomass Monitor for on-line viable biomass measurement of activated sludge from a municipal wastewater plant. In addition, the specific growth rate of the sludge is estimated on-line, based on the information derived from the device under study. Compared to dry weight measurements, the Biomass Monitor hardware offers the advantage of a biologically more appropriate observation of the biomass by only taking into account the viable cells in the population. The optimal measurement frequency of the biomass monitoring device for the given experimental conditions has been determined. Furthermore, the capacitance readings have been correlated with off-line analyses of dry weight of the sludge during the experimental phase in which no death of cells occurred. Finally, an evaluation of the estimator of the specific growth rate including its tuning is presented.
Automatic buffer capacity model building for the purpose of water quality monitoring
Authors: Van Vooren L. , Van De Steene M. , Ottoy J.-P. , Vanrolleghem P. A.
Published: May 2018

In this paper, buffer capacity profiles are used in the framework of automatic monitoring of water quality. The aim of the proposed methodology is to automatically and stepwise build buffer capacity models for each particular titrated sample, and to quantify the individual buffer systems that constitute the total buffer capacity. An automatic and robust model building algorithm has been developed and applied to many titration curves of effluent and river water samples. It is illustrated that the application of automatically built buffer capacity models mostly results in similar or better estimations of ammonium and ortho-phosphate in the samples compared to a priori fixed buffer capacity models. The automatic modelling approach is also advantageous for alarm generating purposes on e.g. river waters, because unexpected buffers are easily detected.
Software sensor design for COD estimation in an anaerobic fluidized bed reactor
Authors: Aubrun C. , Theilliol D. , Harmand J. , Steyer J. P.
Published: May 2018

In this paper, a method for unknown input estimation in stochastic system is presented. A key problem in bioprocess systems is the absence, in some cases, of reliable on-line measurements for real time monitoring applications. In this paper, a software sensor for an anaerobic digester is presented. Unmeasured components of the influent are estimated from available on-line measurements. Unknown input Kalman filter is discussed to estimate the state and unknown input of the process. First, the theory of unknown inputs optimal filtering in the stochastic case is exposed and a design procedure is proposed. The observer is applied to an anaerobic fluidized bed reactor to estimate the variations in Chemical Oxygen Demand (COD) concentration and experimental results are presented.
Parameter optimisation of real-time control strategies for urban wastewater systems
Authors: Schütze M. , Butler D. , Beck M. B.
Published: May 2018

Real-time control (RTC) of wastewater systems has been a topic of research and application for over two decades. Attempts so far have mainly focused on one of the parts of the urban wastewater system: either the sewer system, or the treatment plant or the river. Approaches to integrate these subsystems and considering them jointly for control purposes have been pursued only recently. Control of the system aims at pursuing one (or several concomitant) objectives, which are expressed, for example, in terms of overflow volumes, loads, effluent concentrations, receiving water quality or monetary costs, to name just a few.

This paper provides a general and formal definition of the problem to define a real time control algorithm for a given urban wastewater system. A general mathematical optimization problem is formulated, which describes the task of finding an (in some sense) optimum control algorithm. Since this optimization problem is, in the general case, highly non-linear with only limited information available about the objective function itself, optimization methods appropriate for this type of problem are identified. Here, the similarity of the problem to find a control algorithm and of the parameter estimation problem common in mathematical modelling becomes apparent. Hence, methods (and problems encountered) in parameter estimation can be transferred to the problem of determining optimum RTC algorithms. This parallelism is outlined in the paper.

As an application of the parameterisation and optimization of control strategies, integrated control of an urban wastewater system is discussed. Since the analysis of integrated control as just described poses certain requirements on a simulation engine, a novel modelling tool, called SYNOPSIS, is utilized here. This simulation tool, comprising of modules simulating water quantity and quality processes in all parts of the urban wastewater system, is embedded into a suite of optimization procedures. An integrated RTC algorithm for the urban wastewater system is formulated, the parameters of which are optimized using various global optimization routines. Comparison of their efficiency indicates good performance for the Controlled Random Search and for the genetic algorithms. The findings suggest that integrated control can indeed lead to an increase in performance of the urban wastewater system. These results appear to be encouraging and justify further work. Areas for further development are identified in the final section of the paper.
Microbial degradation of benzene, toluene, ethylbenzene and xylene isomers (BTEX) contaminated groundwater in Korea
Authors: Chang S. W. , La H. J. , Lee S. J.
Published: May 2018

A mixed culture derived from a gasoline-contaminated aquifer in Korea was enriched on toluene at 25°C. A study was conducted to characterize the substrate interaction of BTEX by toluene-enriched consortia and determine the effects of initial BTEX concentration on BTEX degradation. Substrate degradation patterns in individual aromatics were found to differ significantly from patterns for aromatics in mixtures. In the experiment of a single substrate, toluene was degraded fastest, followed by benzene, ethylbenzene, and the xylenes. In BTEX mixtures, degradation followed the order of toluene, ethylbenzene, benzene, and the xylenes. The studies conducting with toluene-enriched consortia evaluated substrate interactions by the concurrent presence of multiple BTEX compounds and revealed a range of substrate interaction patterns including no interaction, stimulation, inhibition, and cometabolism. The simultaneous presence of benzene and toluene were degraded with a slight inhibitory effect on each other. Ethylbenzene was shown to be the most potent inhibitor of BTEX degradation. p-xylene also inhibited the degradation of benzene, toluene, and ethylbenzene, whereas the presence of either benzene or toluene enhanced the degradation of ethylbenzene and the xylenes.
Fast, simultaneous simulation of the integrated urban wastewater system using mechanistic surrogate models
Authors: Meirlaen J. , Huyghebaert B. , Sforzi F. , Benedetti L. , Vanrolleghem P.
Published: May 2018

The urban wastewater system components (sewer, treatment plant, and river) are often modelled using complex mechanistic models. Mechanistic surrogate models are introduced here as simplified models that still contain some physical knowledge. Surrogate models are faster, but are less but still sufficiently accurate, and require more data to be calibrated. The possibilities of replacing actual field data by virtual data generated with a complex mechanistic model for calibration of the surrogate model are examined. As an example, a series of tanks with variable volume is shown to approximate sufficiently well the flow propagation in the river Zwalm (Belgium) as predicted by the “de Saint-Venant” equations.

The three surrogate models can be implemented in the WEST® simulator, which makes a simultaneous simulation of the system possible. In this work a connection is made between the ASM1 and the new IWA River Model No. 1 (RWQM1) by using a translator between the models in such a way that both mass and elemental balances remain closed for the overall system. This approach is illustrated with a case study on the river Lambro (Italy). The dispersion process in this river with steady flow could be modelled by using a tanks in series model, while the water quality in the river was predicted to improve substantially with an increase in hydraulic capacity of the treatment plant. The simulation results with the upgraded plant still need to be checked by field data.
Ranking stormwater control strategies under uncertainty: the River Cam case study
Authors: Duchesne S. , Beck M. B. , Reda A. L.
Published: May 2018

Monte Carlo simulations taking uncertainty in model parameters into account were performed on a river water quality model. The simulation results were used to rank wastewater treatment plant control strategies according to their impacts on river water quality. This impact is estimated by the maximum ammonium concentration and by the duration of dissolved oxygen concentration below 4 g/m3 at the downstream boundary of the system. The strategies were classified according to the previous criteria using 4 ranking methods, one of them being based on the concept of stochastic dominance. Results are presented for a case study based on a 10 km stretch of the River Cam as it passes through the city of Cambridge in Eastern England. It was found that ranking was robust in face of uncertainty in the parameter values for the control strategies considered as being superior in terms of river water quality impacts.
A decade of large scale experience in dissolved air flotation
Authors: Kempeneers S. , Van Menxel F. , Gille L.
Published: May 2018

In April 1990 Antwerpse Waterwerken brought a new DAF-plant into operation at the production centre Notmeir-Walem. The flotation unit, which has a capacity of 200,000 m3/d, was integrated in one of the two existing treatment lines. Its main objective was to eliminate the important raw water quality fluctuations caused by increasing algal growths. During the past ten years several optimisation studies were carried out which resulted in a further simplification of operation and mechanical design. This paper will focus mainly on the integration of dissolved air flotation in the entire treatment line, the consequences on the dual layer filtration and the operational experience and information gathered during the past decade.
Temperature characteristics of methanogenic archaea and acetogenic bacteria isolated from cold environments
Authors: Nozhevnikova A.N. , Simankova M.V. , Parshina S.N. , Kotsyurbenko O.R.
Published: May 2018

In most terrestrial ecosystems of boreal and northern climate zones degradation of organic matter with methane production occurs at low temperature. Two psychrophilic methanogenic archaea and four acetogenic bacteria were described until now. Recently, we isolated 12 new strains of methanogenic archaea and 3 strains of acetogenic bacteria from different natural and man-made cold environments including tundra permafrost wetland, sediments of deep lakes, silt of sludge disposal pond, pig and cattle manure digested at 6°C, and an anaerobic EGSB-reactor operated at 9°C. The temperature characteristics of microorganisms isolated from cold environments are discussed. All isolates are able to grow below 10°C, most of them grow at such low temperature as 1°C. The upper temperature limit for most growing at low temperature acetogens is 30°C, and the temperature optima is 20°C and below. Most isolated methanogens have temperature optima around 25°C, and upper temperature limits at 30-40°C. Whether microorganisms able to grow at low temperature are classified as mesophiles, psychrophiles, or psychrotrophs (psychrotolerants) is an issue of this article. We propose to modify the basic temperature definition of anaerobic microorganisms growing at low temperature.
The potential of anaerobic bacteria to degrade chlorinated compounds
Authors: van Eekert M.H.A. , Schraa G.
Published: May 2018

Chlorinated ethenes and chlorinated aromatics are often found as pollutants in sediments, groundwater, and wastewater. These compounds were long considered to be recalcitrant under anaerobic conditions. In the past years however, dechlorination of these compounds has been found to occur under anaerobic conditions at contaminated sites and in wastewater treatment systems. This dechlorination is mainly attributed to halo-respiring bacteria, which are able to couple this dechlorination to energy conservation via electron transport coupled phosphorylation. The dechlorinating activities of the halo-respiring bacteria seem to be confined to the dechlorination of chloroethenes and chlorinated aromatic compounds. In addition, methanogenic and acetogenic bacteria are also able to reduce the chlorinated ethenes via a-specific cometabolic pathways. Although these latter reactions may not be important in the remediation of contaminated sites, they may be of substantial influence in the start-up of remediation processes and in the application of granular sludge from UASB reactors. Specific halo-respiring bacteria may be used to increase the dechlorination activities via bioaugmentation in the case that the appropriate microorganisms are not present at the contaminated site or in the sludge.
Evaluation of the performance of full-scale packed saturators
Authors: Valade M. , Nickols D. , Haarhoff J. , Barrett K. , Dunn H.
Published: May 2018

An evaluation of the performance of full-scale packed saturators was made. Measurements of saturator effluent air concentrations, saturator efficiency and precipitated are reported for both cold water and warm water operating conditions. Packed saturators were analyzed over a full range of operating pressures and loading rates. Measured results compared to predicted results based on a comprehensive model for the performance of packed saturators prove the model to be a useful tool in designing efficient and cost effective saturation systems.
Corrosion protection by anaerobiosis
Authors: Volkland H.P. , Harms H. , Wanner O. , Zehnder A.J.B.
Published: May 2018

Biofilm-forming bacteria can protect mild (unalloyed) steel from corrosion. Mild steel coupons incubated with Rhodoccocus sp. strain C125 and Pseudomonas putida mt2 in an aerobic phosphate-buffered medium containing benzoate as carbon and energy source, underwent a surface reaction leading to the formation of a corrosion-inhibiting vivianite layer [Fe3(PO4)2]. Electrochemical potential (E) measurements allowed us to follow the buildup of the vivianite cover. The presence of sufficient metabolically active bacteria at the steel surface resulted in an E decrease to -510 mV, the potential of free iron, and a continuous release of ferrous iron. Part of the dissolved iron precipitated as vivianite in a compact layer of two to three microns in thickness. This layer prevented corrosion of mild steel for over two weeks, even in a highly corrosive medium. A concentration of 20 mM phosphate in the medium was found to be a prerequisite for the formation of the vivianite layer.
Collision efficiency factor of bubble and particle (abp) in DAF: theory and experimental verification
Authors: Han M. , Kim W. , Dockko S.
Published: May 2018

The collision efficiency factor of bubble and particle (αbp) in dissolved air flotation (DAF) can be calculated theoretically by trajectory analysis, which takes into account both hydrodynamics and inter-particle forces. To determine the theoretically optimum particle size for any given bubble size, a collision efficiency diagram for DAF was developed where collision efficiency is contoured on a plane of particle and bubble sizes for different conditions of particle zeta potential.

A set of experiments tested the validity of the suggested collision efficiency diagram, and examined whether pretreatment is important and why slight coagulant overdosing and shorter flocculation times are generally preferred in DAF, both current accepted practice. Batch DAF reactors were used and kaolin samples were prepared from jar tests using different alum dosages and flocculation times. The particle size distribution, particle zeta potential, and turbidity removal in each experiment were measured, as were bubble size and zeta potential.

The results agreed well with the predictions of the collision efficiency diagram and explained current practices. A collision efficiency diagram identifies the pretreatment goal, i.e., tailoring of the optimum characteristics required of particles (zeta potential and size) under existing operational bubble characteristic.
Managing waterway health in the Goulburn Broken Catchment, Victoria, Australia
Authors: Tennant W. , Sheed J.
Published: May 2018

Historically within most catchments, resource management programs have been planned and implemented in isolation of one another. This was once the case in the Goulburn Broken Catchment, a major catchment of the Murray Darling Basin, Australia. Although only 2% of the Murray Darling Basin's land area, the catchment generates 11% of the basin's water resources.

Learning from the past, a cooperative and collaborative approach to natural resource programs has developed. This approach is the envy of many other catchment communities and agencies. Through a combination of “Partnership Programs”, “Operational Initiatives” and community involvement, significant programs have been implemented within the catchment, which will benefit not only the local community but communities further afield. The outcomes of the waterway health program highlight the benefits provided through the establishment of cooperative and partnership resource improvement programs. These programs were founded on the ability of the community to recognise the need for integration, base management decisions on best available science and an ability to work together. Their effective delivery has been provided through the resources provided, to the local community, by the Natural Heritage Trust with matching and State and local allocations.

While programs have shown success, challenges still face the community. These challenges include verification and implementation of environmental flows, storage of the catchment's vital water resources, and maintaining community involvement and participation in on-going works programs. The Goulburn Broken Catchment community, with the support of Federal, State and Local Governments, is looking at opportunities for continued improvements in waterway health.
Australia's Environmental Flow Initiative: filling some knowledge gaps and exposing others
Authors: Gippel C. J.
Published: May 2018

Many of Australia's river systems have been seriously degraded by inappropriate management of regulated flows. Other systems are facing threats from future water resources developments. There is a lack of information available to aid in allocation of environmental flows to rivers in order that they are managed in an ecologically sustainable manner. The Environmental Flows Initiative (EFI) is a major Australia-wide R&D program into environmental flows, funded through the Natural Heritage Trust (NHT), and administered by Environment Australia (EA). The program aims to identify environmental values, undertake targeted research to identify risks to river systems and flow requirements to sustain environmental values, to trial flow management options, and to evaluate these trials. The NHT relies on matching funding provided by the State and Territory authorities, and supports integrative approaches with emphasis on works on-the-ground where possible. While the EFI will close significant knowledge gaps, other gaps remain. Some of these relate to development and validation of rapid assessment techniques, understanding the importance of flow variability and how to define it, manipulation of flows to control alien species, developing a system of prioritising rivers for environmental flows, and enhancing flows with other catchment, channel and floodplain rehabilitation measures.
Development of a new dynamic chamber system for measuring harmful gas emissions from composting livestock waste
Authors: Osada T. , Fukumoto Y.
Published: May 2018

A dynamic chamber system consisting of a chamber covering a composting mixture (3 m in diameter, 2.2 m in height, 13 m3), a ventilator for suction of air into the chamber, and equipment to measure the gas composition and indicate temperature, was developed for evaluation of harmful gas emissions from such livestock waste composting. Fresh air was introduced through the space between the floor and the lower edge of the chamber, and exhaust gas was removed through an outlet placed on top of the chamber. NH3, CH4 and N2O concentrations in exhaust air from the chamber were measured by Infrared Photoacoustic Detector (IPD, multi gas monitor type 1312, INNOVA, Copenhagen, Denmark) at 5 minutes intervals. The system was evaluated with standard gas of NH3, CH4 and N2O. High recoveries of 98.5% (NH3, SD 6.25), 96.6% ( CH4, SD 4.03) and 99.5% ( N2O, SD 2.68) were obtained for each gas emission in the chamber over 17-20 min. The measured values of those gases obtained by the IPD method and conventional method at the time of a composting examination of swine waste were measured, and the differences were only a few percent of the total emissions.
Directive on odour in ambient air: an established system of odour measurement and odour regulation in Germany
Authors: Both R.
Published: May 2018

The legal basis for any requirement with respect to ambient air quality is the German Federal Protection Act for Ambient Air. According to §3 Federal Protection Act all odours caused by plants are defined as an annoyance. The problem is to find out whether an annoyance has to be considered as a significant disturbance. In the Directive on Odour in ambient air a complete system is designed, beginning with measurement methods and concluding with ambient air quality requirements. In the following paper the tenor of the Directive on Odour is presented, some main aspects of more than five years of practical experience will be shown and a perspective on some future investigations and developments will be given. As a conclusion it is pointed out that in practice, the Directive on Odours has been successful. Both methods, field measurements with panels and dispersion modelling, are generally qualified for the determination of odour loads. The restriction of odour loads by limit values expressed as odour frequency per year for certain areas has been established in a lot of cases.
Australia versus the World: do we face special opportunities and challenges in restoring Australian streams?
Authors: Rutherford I. D. , Gippel C.
Published: May 2018

Australians do face special opportunities and challenges in attempting to restore or rehabilitate their streams, when compared with Western Europe and North America. Some of these differences arise from the physical and ecological character of our streams, particularly in terms of flow variability, stream power, sediment, vegetation interactions, and nutrient levels. We also have modest resources available per-unit-length of stream, and no massive freshwater fishing industry. These, and many other differences, combine to produce an environment in which it can be slower and more difficult to rehabilitate streams, and we have less confidence in the results. International case studies are tremendously useful but in some cases we need to be circumspect in applying the results directly to Australian streams.
Forecasting rehabilitation outcomes for degraded New Zealand pastoral streams
Authors: Collier K. J. , Rutherford J. C. , Quinn J. M. , Davies-Colley R. J.
Published: May 2018

To understand the timescales and magnitude of responses that can be expected following catchment and riparian rehabilitation, we forecast changes to selected stream ecosystem attributes following tree planting in a pastoral catchment. All planting scenarios were predicted to lead to decreases in daily maximum water temperature after 15-20 years to levels that would be suitable for sensitive invertebrate species. Cooling and reheating were rapid so that most benefits to water temperature along the mainstem were forecast to accrue from shading all of the stream channel network. All planting scenarios were predicted to increase sediment yields over the status quo over the 25-year timeframe examined, with maximal sediment yield occurring about 15 years after planting due to expected erosion of the streambanks under the developing forest shade. Sediment yield was greatest for full catchment planting over 25 years, although sediment yield would be lowest with this scenario over longer timescales. A macroinvertebrate biotic index was predicted to increase by 25% over 15 years if whole catchment afforestation were implemented, compared to 9% if only the 4th order mainstem were planted with riparian trees. The use of ecological forecasting to predict likely outcomes for a range of scenarios should prove useful for prioritising rehabilitation actions.
Catchment management and the Great Barrier Reef
Authors: Brodie J. , Christie C. , Devlin M. , Haynes D. , Morris S. , Ramsay M. , Waterhouse J. , Yorkston H.
Published: May 2018

Pollution of coastal regions of the Great Barrier Reef is dominated by runoff from the adjacent catchment. Catchment land-use is dominated by beef grazing and cropping, largely sugarcane cultivation, with relatively minor urban development. Runoff of sediment, nutrients and pesticides is increasing and for nitrogen is now four times the natural amount discharged 150 years ago. Significant effects and potential threats are now evident on inshore reefs, seagrasses and marine animals. There is no effective legislation or processes in place to manage agricultural pollution. The Great Barrier Reef Marine Park Act does not provide effective jurisdiction on the catchment. Queensland legislation relies on voluntary codes and there is no assessment of the effectiveness of the codes. Integrated catchment management strategies, also voluntary, provide some positive outcomes but are of limited success. Pollutant loads are predicted to continue to increase and it is unlikely that current management regimes will prevent this. New mechanisms to prevent continued degradation of inshore ecosystems of the Great Barrier Reef World Heritage Area are urgently needed.
From river to ridge: a blueprint for sustainable management in the Georges River Catchment
Authors: Nimmo J.
Published: May 2018

Research on sustainable transport and water projects, conducted in North America during 1999, identified four key considerations common to a number of projects. These four considerations are the pre-conditions necessary to achieve sustainability in a given location. These preconditions (BAPP) are boundary definition, administrative alignment, protection of non-urban lands, and the participation of all interested parties.

This paper considers the perceived attitudes of various catchment stakeholders and focuses on planners and planning. The results of questionnaire surveys based on BAPP concepts suggest that local government is perceived as having the highest priority for protection of riparian lands and waterways (as individual Councils and Regional Organisations of Councils). Thus local government is the preferred arena for coordination, responsibility and jurisdiction of waterways and riparian land. The opportunity exists to examine the differing roles of local and state government. The paper concludes by outlining the implications of this research for land use planning and institutional structures in sustainable river management.
Odour emission rates from manure treatment/storage systems
Authors: Edeogu I. , Feddes J. , Coleman R. , Leonard J.
Published: May 2018

The effects of agitation, liquid-only manure, depth and time on odour emission rates were investigated. Manure storage tanks were filled to incremental depths every two weeks. At each depth odour samples were collected twice. The second sample was collected seven days after the first. Odour concentration was measured with an olfactometer. Three different pig-manure treatments were investigated. In one treatment, slurry manure in a storage tank was agitated before and during odour sampling. In a second treatment, the settlable solids in manure were removed gravimetrically over 24 hours and liquid manure was pumped to a storage tank. In the third treatment (control), odour samples were collected from unseparated and undisturbed slurry manure. Overall, the odour emission rates in the agitated manure treatment ranged between 0.39 and 1.02 ou s−1 m−2, increased with depth and decreased with time, i.e. after seven days at each depth. In the liquid-only manure treatment, the emission rates ranged between 0.09 and 0.69 ou s−1 m−2, increased with depth but the effect of time was not evident. In the control treatment, the emission rates ranged between 0.20 and 0.66 ou s−1 m−2 and increased with depth on the first odour sampling day but decreased with depth on the second sampling day.
Removal of odor emitted from composting facilities using a porous ceramic biofilter
Authors: Park S.-J. , Nam S.-I. , Choi E.-S.
Published: May 2018

A field experiment was conducted using a full-scale ceramic biofilter (approximately 150 m3/min) in order to determine the potential for biofiltration to remove malodorous gases from composting facilities. The main compounds found in malodorous gases were NH3 and H2S. These compounds were analyzed by a UV-spectrophotometer and gas chromatograph. The microbial carrier was a porous ceramic consisting of diatomite and fly ash. About 12 m3 of ceramic media inoculated with waste activated sludge were filled in the biofilter. The experimental conditions were space velocity of 500 hr-1, empty bed residence time of 7.2 s, and linear velocity of 0.2 m/s. About 90 L/d of water were sprayed for the operation. The NH3 concentration in inlet gases ranged from 8 to 90 ppmv. The concentration of H2S ranged from 3.2-5.5 ppmv. The acclimation of the biofilter was slow, but more than 95% of removal efficiency was achieved after one month of operation. No nutrients were supplied to the biofilter. The pressure drop in the biofilter varied from 20-40 mmAq during the operation. The energy consumption of this biofilter was about 200 kW/d. It was estimated that the deodorization using this ceramic biofilter was successfully carried out to remove the odor emitted from composting facilities.
Odor control of an anaerobic lagoon with a biological cover: floating peat beds
Authors: Picot B. , Paing J. , Toffoletto L. , Sambuco J.P. , Costa R.H.R.
Published: May 2018

The use of a biological cover for in situ control of gaseous sulfide emission from an anaerobic pond was investigated by a laboratory-scale experiment. The biological cover, constituting by a peat bed floating on the wastewater, caused a reduction of the H2S emission rate by 84.6%. The addition of Fe3+ (with FeCl3) and plants (Juncus effusus L.) to the peat bed significantly improved the performance to reach a H2S removal of 95.5%. Despite the fluctuations in the sulfide concentration in the wastewater, the performance of the biological covers remained constant during the entire period of the study. The analysis of the different forms of sulfur accumulated in the peat beds allowed the understanding of the mechanisms involved in H2S removal. The high amount of sulfate demonstrated that the conditions were favorable to the biological oxidation of H2S. The addition of Fe3+ increased the formation of insoluble ferrous monosulfide (FeS) and pyrite (FeS2). The plants seemed to convert sulfate into elemental and organic sulfur.
Wastewater disinfection by low-pressure UV and ozone: a design approach based on water quality
Authors: Savoye P. , Janex M. L. , Lazarova V.
Published: May 2018

Disinfection processes are known to be very sensitive to wastewater quality. This paper discusses the parameters that impact the UV light (UV) and ozone disinfection processes and the related mechanisms based on literature review. Low-pressure UV and ozone technologies were investigated on effluents that covered a wide range of water quality. The results are given in terms of design doses required to meet three major disinfection standards. Both processes were found eligible for the majority of effluents tested. Although cost-effectiveness is usually considered more favourable to UV, the ozone alternative should be examined in cases such as the disinfection of low-quality effluents or large treatment plants. Ozonation was also found capable of meeting the stringent Title 22 standard with no coagulation at a dose of 10 mg/l.
Prediction of the dewatering of selected inorganic sludges
Authors: Harbour P.J. , Aziz A.A.A. , Scales P.J. , Dixon D.R.
Published: May 2018

There are a number of laboratory techniques traditionally used in the characterisation of sludges for the prediction of the efficient operation of dewatering processes such as centrifugation and filtration. In industry, capillary suction time and specific resistance to filtration measurements are common. Whilst useful in predicting trends, they do not assist in the design and optimisation of devices from first principles.

Recent work in our laboratories has developed a technique for the fast measurement of the permeability and compressibility of sludge. This information, when coupled with first-principle models is useful for the prediction of the performance of solid-liquid separation devices. The work has shown that a single volume fraction dependent parameter, namely the solids diffusivity, calculated from permeability and compressibility, is able to fully characterise the dewaterability of sludge. This allows different sludges to be compared in an unequivocal fashion.

Data will be presented for a range of sludges from different sources showing vastly different dewatering properties. The dewaterability of the different sludges is easily compared and the true role of flocculants in dewatering is highlighted.