bluuebunny/crossref_metadata_2025 huggingface dataset:
Stimulation of phosphate uptake and polyphosphate accumulation by activated sludge microorganisms in response to sulfite addition
Authors: Lai M. W-Y. , Kulakova A. N. , Quinn J. P. , McGrath J. W.
Published: March 2011

Enhanced phosphate removal from wastewaters is dependent on the synthesis and intracellular accumulation of polyphosphate by sludge microorganisms. However the role played by polyphosphate in microbial metabolism and the factors that trigger its formation remain poorly-understood. Many examples of the accumulation of the biopolymer by environmental microorganisms are documented; these include a recent report of the presence of large polyphosphate inclusions in sulfur-oxidizing marine bacteria. To investigate whether any link might exist outside the marine environment between the presence of reduced sulfur compounds and enhanced levels of microbial phosphate uptake and polyphosphate accumulation, activated sludge cultures were grown under laboratory conditions in media that contained sulfite, thiosulfate, hydrosulfite or tetrathionate. Only in the presence of sulfite was there any evidence of a stimulatory effect; in medium that contained 0.5 mM sodium sulfite some 17% more phosphate was removed by the sludge, whilst there was an almost two-fold increase in intracellular polyphosphate levels. No indications of sulfite toxicity were observed.
Seeking a way to promote the use of constructed wetlands for domestic wastewater treatment in developing countries
Authors: Zurita F. , Belmont M. A. , De Anda J. , White J. R.
Published: March 2011

The aim of this study was to evaluate the domestic wastewater treatment efficiency as well as the survivability of commercially valuable ornamental plants in subsurface flow wetlands (SSFW) for domestic wastewater (DWW) treatment in laboratory and pilot wetland studies. The laboratory scale study included five different species (Zantedeschia aethiopica, Strelitzia reginae, Anthurium andreanum, Canna hybrids and Hemmerocallis dumortieri) that were evaluated in horizontal flow subsurface treatment cells. All the plants survived during the 6-month experimental period demonstrating high wetland nutrient treatment efficiency. In order to validate and expand these preliminary results, a pilot-scale wetland study was carried out in SSFWs under two different flow regimes (horizontal and vertical flow). Four ornamental species were tested during a 1-year period: Zantedeschia aethiopica, Strelitzia reginae, Anthurium andreanum and Agapanthus africanus. The removal efficiencies were significantly higher in the vertical subsurface-flow constructed wetlands (VFCW) for all pollutants, except for nitrate (NO3-N), total nitrogen (TN) and total suspended solids (TSS). These results show that it is feasible to use select non-wetland plants with high market value in SSFWs without reducing the efficiency of the wastewater treatment system, although future work should continue in order to apply this technology in a large scale. The added value of floriculture in treatment wetlands can help to promote the use of constructed wetlands (CW) for domestic wastewater treatment in developing countries where economical resources are scarce and water pollution with DWW is common.
Treatment of slaughterhouse wastewater in upflow anaerobic sludge blanket reactor
Authors: Nacheva P. Mijalova , Pantoja M. Reyes , Serrano E. A. Lomelí
Published: March 2011

The performance of an upflow anaerobic sludge blanket (UASB) reactor operated at ambient temperature (20.9–25.2°C) was analysed for the treatment of slaughterhouse wastewater previously pre-treated for solid separation. The experimental work was carried out in a reactor with 15 L effective volume. Four organic loads were applied and the process performance was evaluated. The COD removal rate increased with the load rise from 4 to 15 kg COD.m−3.d−1. Removal efficiencies of 90% were obtained with a load of 15 kg COD.m−3.d−1. The entrapment of suspended solids in the sludge blanket was greater in proportion during the first two stages due to the low upflow velocities used when loads of 4 and 7 kg COD.m−3.d−1 were evaluated. This phenomenon did not affect the structure of the biological grains or their methanogenic activity. More than 50% of the organic nitrogen was degraded, causing a 3% increase of ammonia concentration. The concentrations of the volatile fatty acids were not high and the wastewater alkalinity was enough to prevent acidification. The yield coefficient of methane production increased with the load rise, reaching 0.266 m3/kg CODremoved at 15 kg COD.m−3.d−1 organic load. The UASB reactor is a good option for the biological treatment of pre-treated slaughterhouse wastewater. However, additional treatment is required in order to accomplish the water quality requirements in discharges to water bodies.
Simultaneous nutrients and carbon removal from low-strength domestic wastewater with an immobilised-microorganism biological aerated filter
Authors: Chen Q. , Qu L. , Tong G. , Ni J.
Published: March 2011

To improve the efficiency of low-strength domestic wastewater treatment, an immobilised-microorganism biological aerated filter (I-BAF) was established for simultaneous carbon, nitrogen and phosphorus removal. The I-BAF performance was systematically evaluated under continuous and intermittent aeration modes. At the optimal condition with an intermittent aeration control schedule of 2 h on/1 h off, the maximum removal rates of COD, NH4+-N, TN and P were 82.54%, 94.83%, 51.85% and 61.49%, respectively, and the corresponding averaged effluents could meet the first class standards of China. Further analysis of PCR-DGGE profile revealed that members of the gamma and alpha proteobacterium bacterial groups were probably responsible for the nitrogen and phosphorus removal. The I-BAF system showed excellent performance in carbon and nutrients removal, which provided a cost-effective solution for the treatment of low-strength domestic wastewater.
Toxicity and bioaccumulation potential of Cr (VI) and Hg (II) on differential concentration by Eichhornia crassipes in hydroponic culture
Authors: Giri A. K. , Patel R. K.
Published: March 2011

In this work, the phytoremediation of Cr (VI) and Hg (II) ion from water by an aquatic plant Eichhornia crassipes has been studied. Plants were cultured in a double distillated water with modified Hoagland’s nutrient solution at pH 6.8 supplemented with 0, 0.75, 1.50, 2.50, and 4 mg Cr/L as potassium dichromate (K2Cr2O7) and 0, 5, 10, 15, and 20 mg Hg/L as mercuric chloride (HgCl2). They were separately harvested after 3, 6 and 9 days. Plants treated with 4 mg/L of Cr (VI) accumulated the highest concentration of metal in roots (1.22 mg/g, dry weight) and shoots (0.24 mg/g, dry weight) after 9 days; while those treated with 20 mg/L of Hg (II) accumulated the highest concentration of metal in roots (4.22 mg/g, dry weight) and shoots (2.43 mg/g, dry weight) after 9 days. Eichhornia crassipes biomass was characterised using AAS, SEM and FTIR. The accumulation and relative growth of metal ions at different concentrations of chromium and mercury solution significantly increased (P<0.05) with the passage of time. The maximum values of bio-concentration factor (BCF) for Cr (VI) and Hg (II) were found to be 413.33 and 502.40 L/kg respectively.
Treatment of whey wastewater by supercritical water oxidation
Authors: Söğüt Onur Ö. , Kıpçak Ekin , Akgün Mesut
Published: March 2011

Whey wastewater is a by-product of cheese industry, which causes environmental pollution problems due to its containment of heavy organic pollutants. Conventional methods such as biological treatment and physico-chemical treatment are insufficient or ineffective. In this paper, the treatment of cheese whey wastewater has been carried out by supercritical water oxidation, using hydrogen peroxide as oxidant. The reaction conditions ranged between temperatures of 400–650°C and residence times of 6–21 s under a pressure of 25 MPa. Treatment efficiencies based on TOC removal were obtained between 75.0% and 99.81%. An overall reaction rate model, which consists of the hydrothermal and the oxidation reactions, was determined for the hydrothermal decomposition of the wastewater with an activation energy of 50.022 (±1.7) kJmol−1 and a pre-exponential factor of 107.72 (±4.1) s−1. The oxidation reaction rate orders for the TOC and the oxidant were 1.2 (±0.4) and 0.4 (±0.1) respectively, with an activation energy of 20.337 (±0.9) kJmol−1, and a pre-exponential factor of 1.86 (±0.5) mmol−0.6L0.6s−1 in a 95% confidence level.
Removal of Pb(II) and Cu(II) from aqueous solution using multiwalled carbon nanotubes/iron oxide magnetic composites
Authors: Hu Jun , Zhao Donglin , Wang Xiangke
Published: March 2011

Multiwalled carbon nanotubes (MWCNTs)/iron oxide magnetic composites (named as MCs) were prepared by co-precipitation method, and were characterised by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) in detail. The prepared MCs were employed as an adsorbent for the removal of Pb(II) and Cu(II) ions from wastewater in heavy metal ion pollution cleanup. The results demonstrated that the sorption of Pb(II) and Cu(II) ions was strongly dependent on pH and temperature. The experimental data were well described by Langmuir model, and the monolayer sorption capacity of MCs was found to vary from 10.02 to 31.25 mg/g for Pb(II) and from 3.11 to 8.92 mg/g for Cu(II) at temperature increasing from 293.15 to 353.15 K at pH 5.50. The sorption capacity of Pb(II) on MCs was higher than that of Cu(II), which was attributed to their ionic radius, hydration energies and hydrolysis of their hydroxides. The thermodynamic parameters (i.e., ΔH0, ΔS0 and ΔG0) were calculated from temperature dependent sorption isotherms, and the results indicated that the sorption of Pb(II) and Cu(II) ions on MCs were spontaneous and endothermic processes.
Sludge treatment reed bed facilities – organic load and operation problems
Authors: Nielsen Steen
Published: March 2011

The dewatering of the sludge with loss on ignition between 50 and 65% will have a maximal drainage on the order of 0.008–0.020 L/s/m2. Dewatering of the sludge with loss of ignition higher than 65% of dry solids will have a maximal drainage on the order of only 0.001–0.004 L/s/m2, approximately five to 10 times lower. It can be seen that there is a tendency for the achievable dewatering result to increase with the decrease of loss on ignition or fat in the feed sludge. The correlation shows that if the loss of ignition is higher than 65% of dry solids in the feed sludge the dewatering results in approximately 10% dry solid or lower in the sludge residue, and in approximately 5% dry solid or lower in the sludge residue if the fat concentration is above 10,000 mg/kg ds in the feed sludge. In systems treating sludge with high contents of fat (15,000–30,000 mg/kg ds) and oil (2,300–7,000 mg/kg ds) and if the loss of ignition is higher than 65% (between 65–76%) the dewatering efficiencies only achieve 5–15% dry solid in the sludge residue. In systems treating sludge with low contents of fat (4,000–8,000 mg/kg ds) and oil (50–2,000 mg/kg ds) and with loss on ignition between 50–65% contents of organic solids the dewatering efficiencies achieve 20–37% dry solid in the sludge residue.
The decolorisation capacity and mechanism of Shewanella oneidensis MR-1 for Methyl Orange and Acid Yellow 199 under microaerophilic conditions
Authors: Yang Y. Y. , Du L. N. , Wang G. , Jia X. M. , Zhao Y. H.
Published: March 2011

Shewanella oneidensis MR-1 was found to reach 99.36% and 78.25% decolorisation for Methyl Orange and Acid Yellow 199 in solutions, respectively. The suitable pH range for decolorisation of Methyl Orange and Acid Yellow 199 by S. oneidensis MR-1 was 4.0–7.0 and 6.0–8.0, respectively, The azo dyes' removal by S. oneidensis MR-1 was slightly enhanced by addition of Mg2+, but inhibited by Pb2+, Cd2+, Cu2+, Fe3+ and Fe2+. The enzyme activities of NADH-DCIP reductase and azoreductase were 2.67 and 3.0 times higher, and 1.92 and 2.48 times higher, respectively, in the Methyl Orange treatment and in the Acid Yellow 199 treatment as compared to the control treatment. These findings indicated that the azo dyes' decolorisation by S. oneidensis MR-1 was via reduction mechanism.
Enrichment of marine anammox bacteria in Hiroshima Bay sediments
Authors: Kindaichi T. , Awata T. , Tanabe K. , Ozaki N. , Ohashi A.
Published: March 2011

Anaerobic ammonium oxidation (anammox) involves the microbiological oxidation of ammonium with nitrite as the electron acceptor and dinitrogen gas as the main product. The Scalindua species, an anammox genus that dominates natural habitats, plays an important role in catalysing the loss of nitrogen from marine environments. Until now, a few Scalindua species have been reported to be enriched from sea sediments. The objective of this study is to enrich marine anammox bacteria with coastal sediments in Hiroshima Bay as the inocula. The enrichment was achieved using a continuous upflow column reactor with synthetic sea water containing ammonium and nitrite. After 48 days of incubation, a simultaneous decrease in ammonium and nitrite was observed. A total nitrogen removal rate of 1.16 kg-N m−3 day−1 was attained after 306 days of incubation when the nitrogen loading rate was 1.32 kg-N m−3 day−1. Phylogenetic analysis revealed that the sequence similarity between the marine anammox-like bacteria in this reactor and the unidentified Candidatus Scalindua sp. was 96–98%. We successfully enriched marine anammox bacteria in the sediments of Hiroshima Bay by using synthetic sea water. Further studies are needed to investigate the characteristics of marine anammox bacteria, including optimal pH, temperature, and nitrogen loading rate.
Genotoxicity of swine effluents
Authors: Techio V. H. , Stolberg J. , Kunz A. , Zanin E. , Perdomo C. C.
Published: March 2011

This study aimed at the investigation of genotoxic effects of swine effluents from different stages of a treatment system for swine wastes through bioassay of stamen hairs and micronuclei in Tradescantia (clone BNL 4430). No significant differences (p≥0.05) regarding the genic mutations were found in the bioassay of stamen hairs, independently of the effluent analysed. For the genotoxicity test with micronuclei, the plants exposed to raw wastes, to sludge, and to effluent of the biodigester have presented higher rates of chromosomal damages (micronuclei), with significant differences in relation to the control group and other effluent of the waste treatment system (p≤0.05). The association between the chemical parameters and the genotoxicity data have shown that the variables COD and TKN have presented significant correlation (p≤0.05) with the number of mutagenic events in the tetrads.
Optimisation of reactive dye removal by sequential electrocoagulation–flocculation method: comparing ANN and RSM prediction
Authors: Nourouzi M. Mohsen , Chuah T. G. , Choong Thomas S. Y.
Published: March 2011

The removal of Reactive Black 5 dye in an aqueous solution by electrocoagulation (EC) as well as addition of flocculant was investigated. The effect of operational parameters, i.e. current density, treatment time, solution conductivity and polymer dosage, was investigated. Two models, namely the artificial neural network (ANN) and the response surface method (RSM), were used to model the effect of independent variables on percentage of dye removal. The findings of this work showed that current density, treatment time and dosage of polymer had the most significant effect on percentage of dye removal (p<0.001). In addition, interaction between time and current density, time and dosage of polymer, current density and dosage of polymer also significantly affected the percentage of dye removal (p=0.034, 0.003 and 0.024, respectively). It was shown that both the ANN and RSM models were able to predict well the experimental results (R2>0.8).
Effect of agitation on the performance of an anaerobic sequencing batch biofilm reactor in the treatment of dairy effluents
Authors: Penteado T. Z. , Santana R. S. S. , Dibiazi A. L. B. , de Pinho S. C. , Ribeiro R. , Tommaso G.
Published: March 2011

Agitation rate is an important parameter in the operation of Anaerobic Sequencing Biofilm Batch Reactors (ASBBRs), and a proper agitation rate guarantees good mixing, improves mass transfer, and enhances the solubility of the particulate organic matter. Dairy effluents have a high amount of particulate organic matter, and their anaerobic digestion presents inhibitory intermediates (e.g., long-chain fatty acids). The importance of studying agitation in such batch systems is clear. The present study aimed to evaluate how agitation frequency influences the anaerobic treatment of dairy effluents. The ASBBR was fed with wastewater from milk pasteurisation process and cheese manufacture with no whey segregation. The organic matter concentration, measured as chemical oxygen demand (COD), was maintained at approximately 8,000 mg/L. The reactor was operated with four agitation frequencies: 500 rpm, 350 rpm, 200 rpm, and no agitation. In terms of COD removal efficiency, similar results were observed for 500 rpm and 350 rpm (around 90%) and for 200 rpm and no agitation (around 80%). Increasing the system’s agitation thus not only improved the global efficiency of organic matter removal but also influenced volatile acid production and consumption and clearly modified this balance in each experimental condition.
ANFIS-based approach for the estimation of transverse mixing coefficient
Authors: Ahmad Z. , Azamathulla H. Md. , Zakaria N. A.
Published: March 2011

Understanding of the fate of pollutants, disposed of in streams, is a matter of concern in recent years for the effective control of pollution. Transverse mixing of the pollutants in open channels is arguably more important than the longitudinal mixing and near-field mixing. Several attempts have been made to establish the relationship between the transverse mixing coefficient and bulk channel and flow parameters such as width, depth, shear velocity, friction factor, curvature and sinuosity. This paper presents adaptive neuro fuzzy inference system (ANFIS) approach to predict the transverse mixing coefficient in open channel flows. Available laboratory and field data for the transverse mixing coefficients covering wide range of channel and flow conditions are used for the development and testing of the proposed method. The proposed ANFIS approach produces satisfactory results (R2=0.945) compared to the artificial neural network (ANN) model and existing predictors for mixing coefficient.
Effects of operational parameters on decolorisation of C.I. Reactive Black 5 in UV/TiO2 system
Authors: Wu C. H. , Kuo C. Y. , Hong P. K. A.
Published: March 2011

This study utilises a UV/TiO2 system to decolorise C.I. Reactive Black 5 (RB5). The effects of TiO2 dosage, pH, RB5 concentration and light power on the decolorisation efficiency using the UV/TiO2 system were determined. IO4− was employed as an oxidant to increase the photodegradation efficiency of UV/TiO2. The decolorisation rate constants (k) of RB5 in the UV/TiO2 system are consistent with pseudo-first-order kinetics. The k values of 0.1, 0.5, 1.0 and 2.0 g/l TiO2 were 0.53, 0.52, 0.69 and 0.68 h−1, respectively. The rate constant increases with decreasing pH from 10 to 4. The decolorisation rate approximates linear relationship with RB5 concentration, as given by k=1.05[1/RB5]0.98; it varies nonlinearly with light power, as given by k=0.178[power]0.63. The experimental results reveal that the rate of decolorisation obtained using UV/TiO2/IO4− exceeds that obtained using UV/TiO2.
Zero subsidy strategies for accelerating access to rural water and sanitation services
Authors: Harvey Peter A.
Published: March 2011

Community-Led Total Sanitation (CLTS) and Household-Led Water Supply (HLWS) are zero subsidy approaches to water and sanitation service provision that have been recently piloted in Zambia. The increases in access to sanitation and toilet usage levels achieved in one year under CLTS were far greater than any achieved in subsidised programmes of the past. Similarly, HLWS has shown that rural households are willing to invest in their own infrastructure and that they can increase coverage of safe water without external hardware subsidy. The promotion of self-sufficiency rather than dependency is a key component of both approaches, as is the focus on the development of sustainable services rather than the external provision of infrastructure. Zero subsidy strategies have the potential to deliver far more rapid increases in service coverage and higher levels of sustainability than the conventional subsidised approaches that predominate in low-income countries.
Water reclamation and intersectoral water transfer between agriculture and cities – a FAO economic wastewater study
Authors: Heinz Ingo , Salgot Miquel , Koo-Oshima Sasha
Published: March 2011

Cost–benefit studies on replacing conventional agricultural water resources with reclaimed water in favour of cities are still rare. Some results of a study under auspices of the Food and Agriculture Organisation (FAO) are presented. By means of an illustrative example at Lobregat River basin in Spain, it could be proved that reclaimed water reuse and intersectoral water transfer can result in economic and environmental benefits at the watershed level. The agricultural community faces cost savings in water pumping and fertilising, increases in yields and incomes; the municipality benefits from additional water resources released by farmers. Farmers should be encouraged to participate by implementing adequate economic incentives. Charging farmers with the full cost of water reclamation may discourage farmers from joining water exchange projects. Particularly in regions with water scarcity, investments in reclaimed water reuse and water exchange arrangements usually pay back and are profitable in the long term.
Performance and inhibition recovery of anammox reactors seeded with different types of sludge
Authors: Ni S. Q. , Meng J.
Published: March 2011

In order to study the performance, inhibition and recovery processes of different types of anammox sludge, three up-flow anaerobic sludge blanket reactors were inoculated with flocculent sludge, granular sludge, and cultured inactive methanogenic granules. During stable period, with nitrogen loading rates of 0.9–1.1 kg/m3/d, the total nitrogen removal efficiencies of these reactors averaged at 86.5%, 90.8% and 93.5%, respectively. The kinetics study indicated that the reactor seeded with cultured inactive methanogenic granules possessed the highest nitrogen removal potential, followed by the granular anammox reactor and the flocculent anammox reactor. The study suggested that a concentration as high as 988.3 mg NH4+-N/L and 484.4 mg NO2−-N/L could totally inhibit granular anammox bacteria and result in a inhibition of 50% flocculent anammox activity. In addition, reactors seeded with flocculent sludge and anammox granules could be fully recovered by decreasing their influent substrate concentrations. However, the decrease of influent substrate concentration for the reactor with cultured inactive methanogenic granules could only restore about 75% of its bacterial activity. In this study, anammox bacteria purity was the major factor to evaluate the recovery ability in comparison with sludge type. Free ammonia was a more appropriate indicator for the anammox recovery process compared to free nitric acid.
Application of a risk management framework to a drinking water supply augmented by stormwater recharge
Authors: Vanderzalm J. L. , Page D. W. , Dillon P. J.
Published: March 2011

The Blue Lake is an important water resource for the city of Mount Gambier and the surrounding region, primarily as the drinking water supply source, but also as a tourist attraction. Mount Gambier’s stormwater is discharged directly via drainage wells into the unconfined, karstic Gambier Limestone aquifer, which in turn provides the majority of recharge to Blue Lake. Discharge of urban runoff to the aquifer commenced in the 1800s as a means of stormwater management, but is now recognised as contributing to the drinking water supply in Blue Lake. Recently, guidelines for managing the risks associated with water recycling and augmenting drinking water supplies have been developed. This paper examines the organic chemical hazards associated with a stormwater to potable recycling scheme as an example of the current risk management framework.
Comparison of two treatments for the removal of selected organic micropollutants and bulk organic matter: conventional activated sludge followed by ultrafiltration versus membrane bioreactor
Authors: Sahar E. , Ernst M. , Godehardt M. , Hein A. , Herr J. , Kazner C. , Melin T. , Cikurel H. , Aharoni A. , Messalem R. , Brenner A. , Jekel M.
Published: March 2011

The potential of membrane bioreactor (MBR) systems to remove organic micropollutants was investigated at different scales, operational conditions, and locations. The effluent quality of the MBR system was compared with that of a plant combining conventional activated sludge (CAS) followed by ultrafiltration (UF). The MBR and CAS-UF systems were operated and tested in parallel. An MBR pilot plant in Israel was operated for over a year at a mixed liquor suspended solids (MLSS) range of 2.8–10.6 g/L. The MBR achieved removal rates comparable to those of a CAS-UF plant at the Tel-Aviv wastewater treatment plant (WWTP) for macrolide antibiotics such as roxythromycin, clarithromycin, and erythromycin and slightly higher removal rates than the CAS-UF for sulfonamides. A laboratory scale MBR unit in Berlin – at an MLSS of 6–9 g/L – showed better removal rates for macrolide antibiotics, trimethoprim, and 5-tolyltriazole compared to the CAS process of the Ruhleben sewage treatment plant (STP) in Berlin when both were fed with identical quality raw wastewater. The Berlin CAS exhibited significantly better benzotriazole removal and slightly better sulfamethoxazole and 4-tolyltriazole removal than its MBR counterpart. Pilot MBR tests (MLSS of 12 g/L) in Aachen, Germany, showed that operating flux significantly affected the resulting membrane fouling rate, but the removal rates of dissolved organic matter and of bisphenol A were not affected.
A time-course analysis of four full-scale anaerobic digesters in relation to the dynamics of change of their microbial communities
Authors: Pycke B. F. G. , Etchebehere C. , Van de Caveye P. , Negroni A. , Verstraete W. , Boon N.
Published: March 2011

This study describes the microbial community richness, -dynamics, and -organization of four full-scale anaerobic digesters during a time-course study of 45 days. The microbial community was analyzed using a Bacteria- and Archaea-targeting 16S rRNA gene-based Terminal-Restriction Fragment Length Polymorphism approach. Clustering analysis separated meso- and thermophilic reactors for both archaeal and bacterial communities. Regardless of the operating temperature, each installation possessed a distinct community profile. For both microbial domains, about 8 dominant terminal-restriction fragments could be observed, with a minimum of 4 and a maximum of 14. The bacterial community organization (a coefficient which describes the specific degree of evenness) showed a factor 2 more variation in the mesophilic reactors, compared with the thermophilic ones. The archaeal community structure of the mesophilic UASB reactor was found to be more stable. The community composition was highly dynamic for Bacteria and Archaea, with a rate of change between 20–50% per 15 days. This study illustrated that microbial communities in full-scale anaerobic digesters are unique to the installation and that community properties are dynamic. Converging complex microbial processes such as anaerobic digestion which rely on a multitude of microbial teams apparently can be highly dynamic.
Rural domestic wastewater treatment in Norway and Poland: experiences, cooperation and concepts on the improvement of constructed wetland technology
Authors: Paruch A. M. , Mæhlum T. , Obarska-Pempkowiak H. , Gajewska M. , Wojciechowska E. , Ostojski A.
Published: March 2011

This article describes Norwegian and Polish experiences concerning domestic wastewater treatment obtained during nearly 20 years of operation for constructed wetland (CW) systems in rural areas and scattered settlements. The Norwegian CW systems revealed a high performance with respect to the removal of organic matter, biogenic elements and faecal indicator bacteria. The performance of the Polish CW systems was unstable, and varied between unsatisfied and satisfied treatment efficiency provided by horizontal and vertical flow CWs, respectively. Therefore, three different concepts related to the improvement of CW technology have been developed and implemented in Poland. These concepts combined some innovative solutions originally designed in Norway (e.g. an additional treatment step in biofilters) with Polish inspiration for new CWs treating rural domestic wastewater. The implementation of full-scale systems will be evaluated with regard to treatment efficiency and innovative technology; based on this, a further selection of the most favourable CW for rural areas and scattered settlements will be performed.
Practical automatic control of a sequencing batch reactor for toxic wastewater treatment
Authors: Pat A. M. , Vargas A. , Buitrón G.
Published: March 2011

This paper investigates the application of a practical and robust control strategy for the operation of a sequencing batch reactor (SBR) used for toxic wastewater treatment. The strategy sets the operational conditions of the SBR based on the on-line information collected during the previous batch. In particular, it sets the exchange volume of the reactor, as well as the batch reaction duration by optimizing the amount of mass of substrate in the influent treated per time unit. The optimization uses an experimentally calibrated mathematical model of the previous SBR cycle, found using the on-line dissolved oxygen concentration measurement data. The results show the applicability of the methodology to treat synthetic wastewater containing 4-chlorophenol as model toxic compound as sole source of carbon and energy. It correctly detects changes in the influent concentration and appropriately sets the operational parameters of the process.
DSC: software tool for simulation-based design of control strategies applied to wastewater treatment plants
Authors: Ruano M. V. , Ribes J. , Seco A. , Ferrer J.
Published: March 2011

This paper presents a computer tool called DSC (Simulation based Controllers Design) that enables an easy design of control systems and strategies applied to wastewater treatment plants. Although the control systems are developed and evaluated by simulation, this tool aims to facilitate the direct implementation of the designed control system to the PC of the full-scale WWTP (wastewater treatment plants). The designed control system can be programmed in a dedicated control application and can be connected to either the simulation software or the SCADA of the plant. To this end, the developed DSC incorporates an OPC server (OLE for process control) which facilitates an open-standard communication protocol for different industrial process applications. The potential capabilities of the DSC tool are illustrated through the example of a full-scale application. An aeration control system applied to a nutrient removing WWTP was designed, tuned and evaluated with the DSC tool before its implementation in the full scale plant. The control parameters obtained by simulation were suitable for the full scale plant with only few modifications to improve the control performance. With the DSC tool, the control systems performance can be easily evaluated by simulation. Once developed and tuned by simulation, the control systems can be directly applied to the full-scale WWTP.
Treatability and fate of various phosphorus fractions in different wastewater treatment processes
Authors: Gu A. Z. , Liu L. , Neethling J. B. , Stensel H. D. , Murthy S.
Published: March 2011

The increasingly more stringent phosphorus (P) discharge limits, which are below the concentrations reliably achievable with currently available technologies, demand for better understanding of phosphorus removal mechanisms. This study investigated the compositional fractions of phosphorus (P) in various effluents as well as the efficacy of different levels of treatment processes for removing different fractions of P in wastewater. The results showed that BNR can effectively remove most fractions of P, with relatively higher efficiencies (>93%) towards bioavailable forms of P including soluble reactive P (sRP), particulate reactive P (pRP) portion and particulate acid hydrolysable P (pAHP) and, it showed relatively lower efficiency (78%) towards organic P. Soluble acid hydrolysable P (sAHP) was not effectively removed (<40%). Chemical P removal process was more effective for elimination of sRP, sAHP and particulate organic P (pOP), but was not as effective for removing pAHP and, it exhibited nearly no removal of dissolved organic P (DOP). We found that chemical P removal process led to a significant increase in the concentration of pRP by up to 255%, indicating that these pRP (presumably as chemically bounded P) are likely formed through chemical precipitation/co-adsorption. Only 22% and 64% of the pRP was removed through tertiary clarifier and filtration, respectively. This implies that chemical addition converts sRP into particulate-associated P, mostly as pRP that was not easily removed by sedimentation and filtration, therefore, the efficacy of chemical P removal highly depends on the effectiveness of solid and liquid separation process. As more sRP and particulate P were removed through the series of treatment processes, the percentage contribution from organic P increases with the level of treatment due to its recalcitrant nature. Our results indicated that in order to achieve extremely low effluent P levels, technologies and processes that can enhance pRP and DOP removal will be required.
Nitrogen recovery from source-separated human urine using clinoptilolite and preliminary results of its use as fertilizer
Authors: Beler-Baykal B. , Allar A. D. , Bayram S.
Published: March 2011

The use of source separated human urine as fertilizer is one of the major suggestions of the new sanitation concept ECOSAN. Urine is rich in nitrogen, phosphorus and potassium which act as plant nutrients, however its salinity is high for agricultural and landscape purposes. Moreover, characteristics change significantly throughout storage where salinity increases to higher values as the predominant form of nitrogen shifts from urea to ammonium. Transferring nitrogen in human urine onto the natural zeolite clinoptilolite and using the subsequently recovered ammonium from the exhausted clinoptilolite for agricultural/landscape purposes is suggested as an indirect route of using urine in this work. Results reporting the outcome of the proposed process together with characterization of fresh and stored urine, and preliminary work on the application of the product on the landscape plant Ficus elastica are presented. Up to 97% of the ammonium in stored urine could be transferred onto clinoptilolite through ion exchange and about 88% could be recovered subsequently from exhausted clinoptilolite, giving an overall recovery of 86%. Another important merit of the suggested process was the successful elimination of salinity. Preliminary experiments with Ficus elastica had shown that the product, i.e. clinoptilolite exhausted with ammonium, was compatible with the synthetic fertilizer tested.
Performance of UASB based sewage treatment plant in India: polishing by diffusers an alternative
Authors: Walia R. , Kumar P. , Mehrotra I.
Published: March 2011

In India, recently, upflow anaerobic sludge blanket (UASB) based sewage treatment plants (STPs) have come up in a big way. Sequence adopted: screens- grit chambers- UASB reactors followed by one-day detention ponds (DP). Performance of DPs located at five STPs (27–70 ML/d) was evaluated over a period of one year from July 2004 to July 2005. The installation of these non-algal ponds reduced land requirement, but from treatment point of view it at best offered only removal of solids washed out of the UASB reactor. Total coliform count in the effluent from ponds ranging from 106 to 109 MPN/100 mL is more than the maximum permissible limit of 10,000 MPN/100 mL. A need has, therefore, been felt to evaluate the possibility of aerating the effluent from UASBR. During aeration, ORP and DO increase, whereas COD and BOD decrease. In a continuous aeration ~50% reduction in COD and nearly 50% increase in DO saturation (DO/DOs) can be achieved by increasing ORP from −100 to 122 mV. Regression equation established between ORP and COD/CODi & DO/DOs may find wide application.
An Agent Concept for High Fault Tolerance Wide Area Protection
Authors: Wang Yangguang , Yin Xianggen , You Dahai
Published: March 2011

This paper uses the fault direction information and the distance action information to design a wide area protection agent with high degree of failure tolerance. This protection agent locates the fault by comparing fault direction information. The concept of fault confirmation ring is proposed in this paper. The fault confirmation ring and the distance action information can effectively prevent the incorrect operation of the relay and the communication failure. Then, the division rules of cooperation zones is presented and the structure of protection agent is designed. Referring to the wide area protection algorithm, the dynamic cooperation mechanism is presented. Finally, through the simulation tests, the cooperative process and performance of protection agents are analyzed. Test results manifest that the proposed wide area protection agent with good fault tolerance capability.
Influence of thermal memory on the thermoelastic bending component of photoacoustic response
Authors: Nesic Mioljub , Popovic Marica , Galovic Slobodanka
Published: March 2011

In this work, thermoelastic component of the photoacoustic response is
derived, including thermal memory of the material. The comparison between
this model and the classic one, which does not account for the influence of
thermal memory is made. It has been noticed that the two models tend to
overlap at very high and very low frequencies of the light modulation
spectrum, while in the middle range some deviations become more apparent,
which proves that thermal memory must be taken into account. It has also been
shown that the limits of this range are the function of heat propagation
velocity and thickness of the sample. Based upon the processing of obtained
data, it has been concluded that the characteristics of the output signal, in
the range of the interest, are highly influenced by thermal dynamic
qualities, like heat diffusivity and thermal relaxation time, as well as the
sample thickness.
The literary work of Theodosios of Hilandar: Chronological framework
Authors: Spadijer Irena
Published: March 2011

The period in which Theodosios lived and worked has been one of the more controversial issues raised in the academic circles about this medieval author. Scientific opinions varied considerably on this matter, though in recent years a prevailing theory has been that Theodosios was an author whose literary work can almost certainly be placed in the first couple of decades of the XIV century. This paper re-examines Theodosios' chronology. The manuscripts of Theodosios' works were analyzed first, in order to identify the oldest ones and thus determine the upper time-line of his work. It was concluded that manuscript tradition, from the early decades until mid-XIV century, contained five works of Theodosios, which definitely moves the time they were written in deeper in the past. In our further research we concentrated on the works themselves and their content. A detailed analysis of some works, particularly the Life of St. Sava, resulted in identifying their historical context which, in turn, was significant for determining the time-frame of Theodosios' work. Some episodes from the works, especially the scene of the coronation of Stefan Prvovencani ('the First-Crowned') and the episode with the Hungarian king, hint at certain level of Theodosios' animosity towards the Pope and Catholicism in general. This indicates the period of the Council of Lion (1274) when Byzantium accepted not only the supremacy of the Church of Rome, but also the Roman dogma. Theodosios' discontent, to put it mildly, with Catholic Church and Rome, which is more than evident in the Life of St Sava, could have been a direct reflection of these historical events. It is this anti-Union attitude inherent to Mt. Athos and Hilandar monasticism, to which Theodosios himself belonged, that might have been the reason for writing a new biography of the founder of an independent Serbian Church who was supposed to be the embodiment of all highest spiritual qualities and values of the Orthodox Church which were truly jeopardized at the time. For additional reasons that were elaborated in detail in the article, we opted for the period of king Dragutin's reign (1276-1281) as a logical chronological framework in which the writing of Theodosios' Life of St Sava could be placed. Theodosios may have written the hymnographic works dedicated to St. Sava and Simeon in subsequent years followed by the works dedicated to St Peter of Korisha. In Theodosios' own words, two human generations were separating him from the time when St Peter of Korisha lived. It seems that Theodosios' literary work, in most part belongs to the XIII century.
Hod Bogorodice po mukama u srpskom prepisu sredine XVI veka
Authors: Jovanovic Tomislav
Published: March 2011

nema
Jedan neuspeo pokusaj Luja Vojnovica da postane profesor Velike skole u Beogradu
Authors: Zivkovic-Hristic Zoran
Published: March 2011

nema
O nazivima za zanimanja, zvanja i zanate na epitafima Srpskog Sentandrejskog groblja
Authors: Vulovic Natasa , Djindjic Marija , Radonjic Danijela
Published: March 2011

nema
Effect of Socioeconomic Status on Mortality Among People With Type 2 Diabetes
Authors: Walker Jeremy J. , Livingstone Shona J. , Colhoun Helen M. , Lindsay Robert S. , McKnight John A. , Morris Andrew D. , Petrie John R. , Philip Sam , Sattar Naveed , Wild Sarah H. ,   on behalf of the Scottish Diabetes Research Network Epidemiology Group
Published: March 2011

OBJECTIVE

The study objective was to describe the effect of socioeconomic status (SES) on mortality among people with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We used a population-based national electronic diabetes database for 35- to 84-year-olds in Scotland for 2001–2007 linked to mortality records. SES was derived from an area-based measure with Q5 and Q1 representing the most deprived and affluent quintiles, respectively. Poisson regression was used to estimate relative risks (RRs) for mortality among people with type 2 diabetes compared with the population without diabetes stratified by age (35–64 and 65–84 years), sex, duration of diabetes (<2 and ≥2 years), and SES.

RESULTS

Complete data were available for 210,994 eligible individuals (99.4%), and there were 33,842 deaths. Absolute mortality from all causes among people with type 2 diabetes increased with increasing age and socioeconomic deprivation and was higher for men than women. RR for mortality associated with type 2 diabetes was highest for women aged 35–64 years in Q1 with diabetes duration <2 years at 4.83 (95% CI 3.15–7.40) and lowest for men aged 65–84 years in Q5 with diabetes duration ≥2 years at 1.13 (1.03–1.24).

CONCLUSIONS

SES modifies the association between type 2 diabetes and mortality so that RR for mortality is lower among more deprived populations. Age, sex, and duration of diabetes also interact with type 2 diabetes to influence RR of mortality. Differences in prevalence of comorbidities may explain these findings.
Perinatal Onset Mevalonate Kinase Deficiency
Authors: Steiner Laurie A. , Ehrenkranz Richard A. , Peterec Steven M. , Steiner Robert D. , Reyes-Múgica Miguel , Gallagher Patrick G.
Published: March 2011

Defects in mevalonate kinase, a critical rate-limiting enzyme in cholesterol and isoprene metabolism, have been associated with 2 clinical phenotypes: mevalonic aciduria, which presents in infancy or early childhood with growth failure, dysmorphic features, and neurologic disease; and hyperimmunoglobulinemia D and periodic fever syndrome, which usually presents outside the neonatal period as an autoinflammatory periodic fever syndrome. This report describes a kindred with 2 siblings affected by severe mevalonate kinase deficiency (mevalonic aciduria) with perinatal onset. Dysmorphic and central nervous system abnormalities, anemia, and cholestasis were prominent features in 1 sibling. Both cases were fatal, 1 in the immediate neonatal period and 1 in utero. The small number of cases of mevalonate kinase deficiency presenting in the perinatal period have typically been severely affected, with signs and symptoms of a severe multisystem disorder. Predominant features of perinatal onset mevalonate kinase deficiency include intrauterine growth restriction, cerebral ventriculomegaly, dysmorphic features, skeletal abnormalities, dyserythropoietic anemia with extramedullary erythropoiesis, thrombocytopenia, cholestatic liver disease, persistent diarrhea, renal failure, recurrent sepsis-like episodes, and failure to thrive. Clinical findings may mimic severe intrauterine viral infection, a chromosomal abnormality, or an acute sepsis syndrome, potentially contributing to delays in diagnosis of this rare condition. Perinatal onset mevalonate kinase deficiency is associated with a very poor prognosis, with death in utero or in early infancy. Detailed autopsy findings in mevalonate kinase deficiency have rarely been reported.
Heavy Metal and Bacterial Pollution of the Sava River in Serbia
Authors: Vuković Živorad , Marković Ljiljana , Radenković Mirjana , Vuković Dubravka , Stanković Srboljub
Published: March 2011

Heavy Metal and Bacterial Pollution of the Sava River in Serbia

The aim of this study was to establish microbial and heavy metal pollution of the Sava River at three locations close to industry and urban areas (Šabac, Obrenovac, Beograd) in Serbia. Heavy metal analysis included Cu, Zn, Pb, and Cd in the river water and sediment samples. Using the microbiological analysis we tried to establish the effectiveness of total coliforms, faecal coliforms and Escherichia coli in detecting pollution of surface waters. We found that E. coli levels steadily increased downstream from Šabac (location 1; 2100 MPN per 100 mL) to Belgrade (location 3; 10000 MPN per 100 mL). To prevent bacterial contamination, it is necessary to reduce the discharge of wastewater with faecal matters near highly populated towns. Heavy metal levels in sediments correlated with those in the river water. Fluctuations attributed mainly to anthropogenic sources were not high. These results point to acceptable anthropogenic contribution to heavy metal content in the Sava River and to low environmental risk.