Waste Water (waste + water)

Distribution by Scientific Domains
Distribution within Chemistry

Terms modified by Waste Water

  • waste water treatment

  • Selected Abstracts

    Ground Water Recharge Using Recycled Municipal Waste Water in Los Angeles County and the California Department of Public Health's Draft Regulations on Aquifer Retention Time

    GROUND WATER, Issue 4 2009
    Theodore A. Johnson
    First page of article [source]

    Fermentation of Cucumbers Brined with Calcium Chloride Instead of Sodium Chloride

    Roger F. McFeeters
    ABSTRACT:, Waste water containing high levels of NaCl from cucumber fermentation tank yards is a continuing problem for the pickled vegetable industry. A major reduction in waste salt could be achieved if NaCl were eliminated from the cucumber fermentation process. The objectives of this project were to ferment cucumbers in brine containing CaCl2 as the only salt, to determine the course of fermentation metabolism in the absence of NaCl, and to compare firmness retention of cucumbers fermented in CaCl2 brine during subsequent storage compared to cucumbers fermented in brines containing both NaCl and CaCl2 at concentrations typically used in commercial fermentations. The major metabolite changes during fermentation without NaCl were conversion of sugars in the fresh cucumbers primarily to lactic acid which caused pH to decrease to less than 3.5. This is the same pattern that occurs when cucumbers are fermented with NaCl as the major brining salt. Lactic acid concentration and pH were stable during storage and there was no detectable production of propionic acid or butyric acid that would indicate growth of spoilage bacteria. Firmness retention in cucumbers fermented with 100 to 300 mM CaCl2 during storage at a high temperature (45 °C) was not significantly different from that obtained in fermented cucumbers with 1.03 M NaCl and 40 mM CaCl2. In closed jars, cucumber fermentations with and without NaCl in the fermentation brine were similar both in the chemical changes caused by the fermentative microorganisms and in the retention of firmness in the fermented cucumbers. [source]

    Highly Selective and Sensitive Tin(II) Membrane Electrode Based on a New Synthesized Schiff's Base

    ELECTROANALYSIS, Issue 7 2009
    Morteza Hosseini
    Abstract Studies on complex formation of tris(3-(2-hydroxybenzophenone)propyl)amine (THPA) with a number of metal ions in acetonitrile solution revealed the occurrence of a selective 1,:,1 complexation of the proposed ligand with Sn2+ ion. Consequently, THPA was used as a suitable neutral ionophore for the preparation of a polymeric membrane-selective electrode. The electrode exhibits a Nernstian behavior with a slope of 29.4±0.3,mV per decade and a detection limit of 2.0×10,7 M. It also showed a good selectivity for Sn2+ ions in comparison with some of group A and B metal ions over a wide concentration range of 5.0×10,7,1.0×10,1 M. Improved selectivity was achieved compared to the best selectivity recently reported by other authors for tin(II). The electrode was successfully applied to the determination of Sn2+ ion in waste water and various canned products. [source]

    Automatic Voltammetric System for Continuous Trace Metal Monitoring in Various Environmental Samples

    ELECTROANALYSIS, Issue 19-20 2007
    Øyvind Mikkelsen
    Abstract Some recent developments and results in the field of automatic monitoring of electrolabile concentration of zinc and iron in the low ,g/L range in river water, drainage water, and waste water by use of solid dental amalgam electrode (DAM) as a working electrode are reviewed for three different geographical sites representing the mentioned matrixes. At all sites, voltammetric measurements were carried out continuously every 30 or 60,minutes for periods up to 4,months, and compared with total amounts of the metals found by ICP-MS on manually collected samples. In total, the observed concentration ranges analyzed was in the ranges of sub-,g/L to approximately 30,,g/L for zinc, and from approximately 1,,g/L to 150,,g/L. for iron. Results shows good calibration curves for the metals in the different matrixes (r2avg=0.99) with standard deviation within 5%. The voltammetric system showed good stability and gave reliable results which were in a reasonable agreement with ICP-MS measurements for all analyses when comparing the concentration trends. The frequency of maintenance varied from once a week in waste water samples to once a month in river water. [source]

    Electrocatalytic Oxidation and Voltammetric Determination of Hydrazine on the Tetrabromo- p -Benzoquinone Modified Carbon Paste Electrode

    ELECTROANALYSIS, Issue 5 2007
    Jahan-Bakhsh Raoof
    Abstract The electrochemical properties of hydrazine studied at the surface of a carbon paste electrode spiked with p -bromanil (tetrabromo- p -benzoquinone) using cyclic voltammetry (CV), double potential-step chronoamperometry and differential pulse voltammetry (DPV) in aqueous media. The results show this quinone derivative modified carbon paste electrode, can catalyze the hydrazine oxidation in an aqueous buffered solution. It has been found that under the optimum conditions (pH,10.00), the oxidation of hydrazine at the surface of this carbon paste modified electrode occurs at a potential of about 550,mV less positive than that of a bar carbon paste electrode. The electrocatalytic oxidation peak current of hydrazine showed a linear dependent on the hydrazine concentrations and linear analytical curves were obtained in the ranges of 6.00×10,5 M,8.00×10,3 M and 7.00×10,6 M,8.00×10,4 M of hydrazine concentration with CV and differential pulse voltammetry (DPV) methods, respectively. The detection limits (3,) were determined as 3.6×10,5 M and 5.2×10,6 M by CV and DPV methods. This method was also used for the determination of hydrazine in the real sample (waste water of the Mazandaran wood and paper factory) by standard addition method. [source]

    REACH-driven developments in analysis and physicochemistry,

    A. Chaintreau
    Abstract The enforcement of the REACH regulation in the fragrance domain has created new challenges for the analytical and physical chemist. Many chemicals used as perfumery ingredients are hydrophobic, because low-polar compounds exhibit a higher substantivity (i.e. persistence after application) than do polar compounds. As a result, the usual protocols are often unsuitable and new methods must be developed. Biodegradation studies sometimes call for the quantification of traces of such hydrophobic analytes in complex media (e.g. waste water, aqueous surfactant solutions). Existing sample preparation techniques are either inefficient or time consuming. A new approach is proposed, based on single-use absorbants, which allows accurate quantification down to the 100 ppb range. This extremely simple technique allows good throughput analyses. Determining the environmental profile of a compound requires the determination of some physical constants. Among these, solubility in water can be obtained from theoretical models or experimentally, but the resulting values may greatly differ as a function of the model or the protocol. Several experimental approaches are critically discussed and compared with a reference technique. The air-to-water partition coefficients are determined by using an improved version of the previously developed static-and-trapped headspace technique. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Cutting frequency and stubble height of reed canary grass (Phalaris arundinacea L.): influence on quality and quantity of biomass for biogas production

    GRASS & FORAGE SCIENCE, Issue 4 2002
    U. Geber
    Abstract Reed canary grass (RCG) used for land treatment of waste water can serve as a substrate for biogas production. The aim of this experiment was to study the effects of two, three or four cuts per year to stubble heights of 5, 12·5 or 20 cm on the digestibility and yield of digestible organic matter (DOM) of RCG. Both dry-matter yield and the yield of DOM decreased with more than two cuts per year. Height of cutting had no effect on the digestibility of the regrowth harvested from the different cutting regimes. Increased height of cutting resulted in increased dry-matter production and therefore also of increased DOM yield in the regrowth harvested from the four-cut regime. The total DOM yield from the four-cut regime was, however, only 0·84 of the DOM yield from the two-cut regime. [source]

    Identifying the Potential Loss of Monitoring Wells Using an Uncertainty Analysis

    GROUND WATER, Issue 6 2005
    Vicky L. Freedman
    From the mid-1940s through the 1980s, large volumes of waste water were discharged at the Hanford Site in southeastern Washington State, causing a large-scale rise (>20 m) in the water table. When waste water discharges ceased in 1988, ground water mounds began to dissipate. This caused a large number of wells to go dry and has made it difficult to monitor contaminant plume migration. To identify monitoring wells that will need replacement, a methodology has been developed using a first-order uncertainty analysis with UCODE, a nonlinear parameter estimation code. Using a three-dimensional, finite-element ground water flow code, key parameters were identified by calibrating to historical hydraulic head data. Results from the calibration period were then used to check model predictions by comparing monitoring wells' wet/dry status with field data. This status was analyzed using a methodology that incorporated the 0.3 cumulative probability derived from the confidence and prediction intervals. For comparison, a nonphysically based trend model was also used as a predictor of wells' wet/dry status. Although the numerical model outperformed the trend model, for both models, the central value of the intervals was a better predictor of a wet well status. The prediction interval, however, was more successful at identifying dry wells. Predictions made through the year 2048 indicated that 46% of the wells in the monitoring well network are likely to go dry in areas near the river and where the ground water mound is dissipating. [source]

    Chemical and Bacterial Quality of Aeration-Type Waste Water Treatment System Discharge

    Samuel V Panno
    On-site waste water treatment systems are a potential source of chemical and bacterial contamination to ground water in areas with highly susceptible aquifers such as the sinkhole plain of southwestern Illinois. Ground water from wells, cave streams, and water that discharges from the numerous springs in this area is typically contaminated with nitrate and enteric bacteria and thus may pose a health hazard to those who come into contact with it. In order to determine if the most popular type of on-site waste water treatment systems in the study area was a potential source, samples of effluents discharged at the land surface from 23 domestic aeration-type on-site waste water treatment systems were collected to characterize their water quality and bacterial contents. Most of the effluents contained relatively large concentrations of sodium (Na+), chloride (Cl,), nutrients (nitrogen [N], phosphate [PO43,], and potassium [K+]), and enteric bacteria. Ion concentration ranges (in mg/L) were Na+ (46 to 416), Cl, (21 to 618), N (4.7 to 67), PO4 -P (1.4 to 48), and K+ (6.0 to 257). The sources of elevated Na+ and Cl, were human waste and NaCl used in the water softening systems of the houses. Ammonium was usually the dominant inorganic N species, indicating incomplete oxidation of the waste water. Discharge of Na+, Cl,, and nutrients could also have negative impacts on ground water and surface water quality, subsurface and surface aquatic ecosystems, and vegetation. Our characterization of effluent from these waste water treatment systems revealed their generally poor quality and the likelihood that they can contaminate ground water in areas with highly vulnerable aquifers. [source]

    Ground Water Recharge and Chemical Contaminants: Challenges in Communicating the Connections and Collisions of Two Disparate Worlds

    Christian G. Daughton
    Our knowledge base regarding the presence and significance of chemicals foreign to the subsurface environment is large and growing , the papers in this volume serving as testament. However, complex questions with few answers surround the unknowns regarding the potential for environmental or human health effects from trace levels of xenobiotics in ground water, especially ground water augmented with treated waste water. Public acceptance for direct or indirect ground water recharge using treated municipal waste water (especially sewage) spans the spectrum from unquestioned embrace to outright rejection. In this paper, I detour around the issues most commonly discussed regarding ground water recharge and instead focus on some of the less-recognized issues,those that emanate from the mysteries created at the many literal and virtual interfaces involved with the subsurface world. My major objective is to catalyze discussion that advances our understanding of the barriers to public acceptance of waste water reuse with its ultimate culmination in direct reuse for drinking. I pose what could be a key question as to whether much of the public's frustration or ambivalence in its decision-making process for accepting, or rejecting, water reuse (for various purposes including personal use) emanates from fundamental inaccuracies, misrepresentation, or oversimplification of what water is and how it functions in the environment,just exactly what the water cycle is. These questions suggest it might behoove us to revisit some very elementary aspects of our science and how we are conveying them to the public. [source]

    Controlled Preparation of MnO2 Hierarchical Hollow Nanostructures and Their Application in Water Treatment,

    ADVANCED MATERIALS, Issue 3 2008
    B. Fei
    Hierarchical hollow manganese dioxide nanosheets with intricate and well-controlled 3D morphologies are synthesized by combining the Kirkendall effect with a sacrificial crystalline template. The as-prepared MnO2 nanomaterials (see figure) exhibit a good absorbing ability, useful in the removal of organic pollutants from waste water. [source]

    Comparative study of the efficacy of three coagulants in treating dairy factory waste water

    The treatment of dairy factory waste water by coagulation and decantation has shown that calcium hydroxide at a weak dose of 0.49,0.63 g provides the highly efficient removal of suspended matter (SM) (94%) and total phosphorus (Tp-P) (89%) accompanied by an average elimination of chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN-N), faecal coliforms (FC) and faecal streptococci (FS). This is within the Moroccan limits for the first two parameters (SM and TP-P). The dose necessary to obtain optimal removal is 0.8,1.2 g when using aluminium sulfate and 0.6,0.75 g with iron chloride and the percentage elimination of chemical and bacteriological pollutants is not substantial. However, coagulation by calcium hydroxide induced less sludge (0.93 g/L) than either aluminium sulfate (1.21 g/L) or iron chloride (1.38 g/L). In terms of cost, the price of treating 1 m3 of dairy effluent by using calcium hydroxide is lower (approximately 25 times less expensive) than when using the other two coagulants. [source]

    Effect of textile waste water on the spermatogenesis of male albino rats

    R. S. Gupta
    Abstract Textile waste water released from dyeing and printing industries situated in Sanganer, Jaipur (India), brought about inhibition of spermatogenesis in male rats. Water analysis showed the presence of heavy metals at more than permissible limits. Oral administration of waste water to the rats at the dose level of 26.6 ml kg,1 body wt. significantly reduced the weights of testes, epididymides and seminal vesicle. Treated animals showed a notable depression of various stages of spermatogenesis. The production of spermatids was inhibited by 70.8% in waste-water-treated rats. The populations of spermatogonia, preleptotene spermatocytes and secondary spermatocytes were decreased by 67.2, 71.1 and 73.2%, respectively. The total number of Sertoli cells was affected after waste water treatment. Reduced sperm count and motility resulted in treated groups. A significant fall in the content of various biochemical parameters of reproductive tissues was observed after water treatment. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Olive oil mill waste water as a replacement for fresh water in the manufacture of fired clay bricks

    Houda Mekki
    Abstract This paper describes the introduction of olive mill wastewater (OMW) to replace fresh water normally used in clay brick manufacture. OMW is recognised as the major agro-food industry pollutant in the Mediterranean/North African olive-growing region. The research involved adding OMW to laboratory-produced clay bricks following the same making procedure used at a collaborating Tunisian brick factory. The samples containing OMW were found to be comparable in forming/extrusion performance to a control product that used fresh water. If introduced at the factory scale, this innovation would allow a substantial volume of OMW to be recycled, saving on the fresh water currently used in the brick-forming process. During the subsequent brick drying operation, most of the OMW (,98% water) would be released as vapour. Once in the kiln, the remaining solids in the bricks (calorific value 21,23 MJ kg,1) would liberate additional heat, reducing the gross energy from fossil fuel currently required during firing. Copyright © 2006 Society of Chemical Industry [source]


    ABSTRACT A large amount of waste permeates generated from the processing of yellow mustard protein was concentrated fivefold using a nanofilter with a molecular weight cut off of 1,000 Da, while approximately 74% of sinapic acid was retained. Sinapic acid was then released from sinapine, its esterified form, by an alkaline hydrolysis. The hydrolyzed solution was acidified to prevent oxidation of the sinapic acid and to precipitate the remaining proteins. Subsequently, sinapic acid and other phenolics were extracted by a two-stage extraction using a mixture of diethyl ether and ethyl acetate (1:1), 165-min extraction time and permeate-to-solvent ratio of 1:2. Approximately 95% of the sinapic acid in the acidified permeate was finally concentrated in the solvent phase. PRACTICAL APPLICATIONS This development has led to an economical process to recover phenolics and to treat effluent from a process of oilseed protein while reducing the use of water during the extraction of protein. A reduction of water usage makes the processing of oilseed protein isolate more economically attractive, and the recovered phenolics may find a use as a nutraceutical. The developed process is not only limited to the recovery of phenolics from mustard, but also applied for recovering phenolic acids, specifically sinapic acid, from waste water from membrane processing of protein from mustard and similar polyphenol-containing oilseeds. [source]

    Ultrasound-facilitated electro-oxidation for treating cyan ink effluent

    Chee-Yong Chua
    Abstract The feasibility of using ultrasonication in combination with the Fenton's reaction was investigated for treating cyan ink effluent. A two-step treatment process was developed,the first step was an ultrasound-assisted electro-oxidation, while the second was chemical oxidation through the addition of hydrogen peroxide. The use of electro-oxidation in the first step significantly reduced the amount of iron needed compared with the conventional Fenton's reaction, resulting in a 98% reduction in the amount of sludge produced. A simple technique based on refractive index measurements was introduced as a rapid way to quantify the amount of sludge produced. It was postulated that ultrasonication in the presence of iron (from electrolysis) in the first step converted the ink components into reaction intermediates which were more amenable to peroxide oxidation in the second step. These intermediates were quantified by ultra-violet absorption at wavelengths of 275,400 nm. The two-step treatment process was able to reduce the COD and copper contents in the ink waste water to within the discharge limit, which conventional Fenton's reaction was unable to meet for copper discharge. The same COD removal was also achieved in about half the time. Kinetics study performed to further understand the reaction mechanisms show second-order kinetics for both steps with activation energies of 18.2 and 20.4 kJ/mol for steps 1 and 2, respectively. On a étudié la possibilité de recourir à l'ultrasonification combinée à la réaction de Fenton pour traiter l'effluent d'encre de cyan. Un procédé de traitement en deux étapes a été mis au point: la première étape consiste en une électro-oxydation assistée par ultrasons, tandis que la seconde consiste en une oxydation chimique par ajout de peroxyde d'hydrogène. Le recours à l'électro-oxydation dans la première étape réduit significativement la quantité de fer requis comparé à la réaction de Fenton classique, entraînant une réduction de 98% de la quantité de suspension produite. Une technique simple basée sur des mesures d'indice de réfraction a été introduite comme une façon rapide d'établir la quantité de suspension produite. On a posé comme postulat que l'ultrasonification en présence de fer (de l'électrolyse) dans la première étape convertit les composantes de l'encre en des intermédiaires de réaction qui étaient plus propices à l'oxydation du peroxyde dans la seconde étape. Ces intermédiaires ont été quantifiés par l'absorption des ultraviolets à des longueurs d'ondes de 275 nm à 400 nm. Ce procédé de traitement en deux étapes a permis de réduire la DCO et les teneurs en cuivre dans l'eau usée de l'encre pour les amener à la limite des normes de rejet, ce que la réaction de Fenton classique n'a pu permettre de réaliser pour le cuivre. Le même retrait de DCO a été également réalisé dans un temps inférieur de 50%. L'étude de cinétique effectuée pour mieux comprendre les mécanismes de réaction montre une cinétique de second ordre pour les deux étapes avec des énergies de désactivation de 18,2 et 20,4 kJ/mol pour les étapes 1 et 2, respectivement. [source]

    Modélisation de la cinétique de biodégradation de phénol par granules aérobies

    Claudia Calvario-Rivera
    Abstract Ce travail est consacré à la modélisation de la cinétique de biodégradation de phénol par granules aérobies. Ceux-ci ont été obtenus à partir de la culture à alimentation séquentielle d'un surnageant de boues activées sur une eau usée synthétique,; puis ils ont été acclimatés au phénol (100 mg/L). La biodégradation de différentes concentrations de phénol (40,1112 mg/L) a été étudiée en fioles agitées ensemencées avec des granules acclimatés. Un modèle de type Haldane a été sélectionné, qui permet de décrire de manière adéquate l'évolution de la concentration de phénol avec un seul jeu de paramètres. Ce modèle pourrait permettre de mieux comprendre la biodégradation de molécules toxiques telles que le phénol dans des réacteurs granulaires aérobies. This work describes a model of the biodegradation of phenol carried out by aerobic granules. These granules were obtained by culturing an activated sludge supernatant in a sequencing batch reactor fed with a synthetic waste water and subsequently, by acclimation to phenol (100 mg/L). The kinetics of phenol biodegradation by the aerobic granules was investigated over a wide range of initial phenol concentrations (40,1112 mg/L) in shake-flask cultures. A Haldane-type model was adjusted to the experimental results, which depicts successfully the phenol biodegradation profiles in the entire range of initial concentrations studied by using only one set of parameters. It is our view that the proposed model could contribute to the knowledge about the ability of aerobic granular systems to biodegrade toxic, inhibitory compounds such as phenol. [source]

    Energetisch und bauphysikalisch optimierte Sanierung eines Baudenkmals in Görlitz

    BAUPHYSIK, Issue 3 2007
    Christian Conrad Dipl.-Ing.
    Mit den angewendeten Sanierungsmassnahmen an einem barocken Gebäude in Görlitz (Innendämmung Straßenfassade, WDVS Hoffassade, Solaranlage, Lüftungsanlage mit WRG, Grauwassernutzung und Fußbodenabwasserheizung) wurden unter Einhaltung der Auflagen des Denkmalschutzes die Energieeffizienzklasse A+ erreicht, die Belange des Umweltschutzes berücksichtigt und die Dauerhaftigkeit und Zuverlässigkeit der Konstruktionen gewährleistet. Die erreichten Ergebnisse werden u.a. mit instationären Simulationsrechnungen (Wärme-, Luft- und Feuchtetransport in kapillarporösen Baustoffen) für die einzelnen Bauteile und instationären Simulationsrechnungen anlagentechnischer Komponenten verifiziert. Dabei wird bauphysikalisch der Einfluss der hohen Bauwerksmasse ganzjährig quantifiziert. Die Auswirkungen der eingesetzten Anlagentechnik auf historische Bauteile, wie z. B. die Holzbalkendecken, werden untersucht. Auf der Grundlage der Erfahrungen zur Vermeidung der Kondensat- und Reifbildungen bei hochdämmenden geneigten Verglasungen wurde gemeinsam mit einem ortsansässigen Glaswerk eine neue Wärmeschutzverglasung mit einer außenliegenden Beschichtung entwickelt/kombiniert und eingesetzt. Optimized energy saving rehabilitation of a baroque building monument. With the rehabilitation of the baroque building Handwerk 15 in Görlitz the authors achieved the energy efficiency class A+ under observance of all conditions from preservation of historic buildings and monuments, taking into account the environmental issues as well as durability and safety of the constructions in the house. The rehabilitation includes the internal thermal insulation of the historically valuable façade on the street side, the thermal insulation of the façade on the backyard side, the use of solar energy for hot water and for the support of heating especially in summer for heating the ground floor, a ventilation system with heat exchanger, the use of gray water generated from domestic processes such as laundry and bathing, and an underfloor heating for the ground floor with waste water as medium. The measurement results will be verified with numerical simulations (temperature, air, moisture transport in porous materials) of the separate building constructions and the technical components. The physical influence of the high building mass is quantified. The effects of the HVAC system on the historical building construction like for instance the timber beam floor will be investigated. Based on experiences about avoiding condensate and hoarfrost on inclined insulated glass together with a glass producing firm a new insulate glass with a special coating was developed. [source]

    Erratum: Screening co-digestion of food waste water with manure for biogas production.

    Steve A. Miller, Steven I. Safferman., Yan Liu
    The original article to which this Erratum refers was published in Biofuels, Bioproducts and Biorefining, 2009 [source]

    Screening co-digestion of food waste water with manure for biogas production

    Yan Liu
    Abstract Anaerobic digestion, an environmental protection technology for treating organic compounds in waste water, produces biogas, resulting in a renewable energy source. A protocol including waste analysis, waste blending, energy potential and energy balance calculations was developed to determine the energy production from blending food and animal wastes. Fruit and vegetable waste water produced from crop commodity processing was characterized in terms of quantity and 5-day biochemical oxygen demand (BOD). Often these wastes have high levels of degradable carbon but lack buffering capacity and adequate nitrogen and other nutrients to meet the minimal C/N ratio needed for optimal digestion. Blending food-processing waste water with high nutrient manure can enhance the biogas production by optimizing nutrient levels and providing buffering capacity. The protocol shows the procedure to determine the optimal blend and theoretical biogas production from the anaerobic digestion of that blend. An energy balance technique that determines the lowest COD concentration required to close the energy balance in the digester during different seasons is illustrated. A case study was conducted to determine the potential energy production from anaerobically digesting blended waste water from the top 14 fruit and vegetable commodities in Michigan. The resulting biogas production supports a substantial amount of the energy consumption needed for the treatment process. This case study in Michigan can be extended to national level since the calculations were based on the mean value of their typical range. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd [source]

    Low-temperature (9°C) AMD treatment in a sulfidogenic bioreactor dominated by a mesophilic Desulfomicrobium species

    Hannele Auvinen
    Abstract The possibilities for the treatment of low-temperature mine waste waters have not been widely studied. The amenability of low-temperature sulfate reduction for mine waste water treatment at 9°C was studied in a bench-scale fluidized-bed bioreactor (FBR). Formate was used as the electron and carbon source. The first influent for the FBR was acidic, synthetic waste water containing iron, nutrients, and sulfate, followed by diluted barren bioleaching solution (DBBS). The average sulfate reduction rates were 8,mmol,L,1,day,1 and 6,mmol,L,1,day,1 with synthetic waste water and DBBS, respectively. The corresponding specific activities were 2.4 and 1.6,mmol SO,g VSS,1 day,1, respectively. The composition of the microbial community and the active species of the FBR was analyzed by extracting the DNA and RNA, followed by PCR-DGGE with the universal bacterial 16S rRNA gene primers and dsrB -primers specific for sulfate-reducing bacteria. The FBR microbial community was simple and stable and the dominant and active species belonged to the genus Desulfomicrobium. In summary, long-term operation of a low-temperature bioreactor resulted in enrichment of formate-utilizing, psychrotolerant mesophilic sulfate reducing bacteria. Biotechnol. Bioeng. 2009; 104: 740,751 © 2009 Wiley Periodicals, Inc. [source]

    Composite Multienzyme Amperometric Biosensors for an Improved Detection of Phenolic Compounds

    ELECTROANALYSIS, Issue 22 2003
    B. Serra
    Abstract A biosensor design, in which glucose oxidase and peroxidase are coimmobilized by simple physical inclusion into the bulk of graphite-Teflon pellets, is reported for the detection of phenolic compounds. This design allows the "in situ" generation of the H2O2 needed for the enzyme reaction with the phenolic compounds, which avoids several problems detected in the performance of single peroxidase biosensors as a consequence of the presence of a high H2O2 concentration. So, a much lower surface fouling was found at the GOD-HRP biosensor in comparison with a graphite-Teflon-HRP electrode, suggesting that the controlled generation of H2O2 makes more difficult the formation of polymers from the enzyme reaction products. The construction of trienzyme biosensors, in which GOD, HRP and tyrosinase were coimmobilized into the graphite-Teflon matrix is also reported, and their performance was compared with that of GOD-HRP bienzyme electrodes. The practical applicability of the composite multienzyme amperometric biosensors was evaluated by the estimation of the phenolic compounds content in waste waters from a refinery, and the results were compared with those obtained by using a colorimetric official method based on the reaction with 4-aminoantipyrine. [source]

    Towards Higher Laccase Activities Produced by Aquatic Ascomycetous Fungi Through Combination of Elicitors and an Alternative Substrate

    C. Junghanns
    Abstract Laccases are versatile biocatalysts with various potential biotechnological applications, e.g. the treatment of industrial waste waters, the detoxification of environmental pollutants, or the functionalization of renewable polymeric materials. Central composition experimental design and response surface methodology was applied to optimize the production of laccase by the aquatic ascomycetous fungi, Phoma sp. UHH 5-1-03 and Coniothyrium sp.,Kl-S5, in shake flasks. A complex plant-based medium (tomato juice) and two elicitors (Remazol Brilliant Blue R [RBBR] and CuSO4) were tested in combination at three concentrations. The highest laccase activity of 6322,±,403,U/L was achieved on day,9 for Phoma sp. Coniothyrium sp. exerted a maximum laccase activity of 3035,±,111 U/L on day,4. Optimal conditions were 30,% tomato juice and 450,mg/L RBBR for both strains. A concentration of 250,,M CuSO4 led to highest laccase activities in cultures of Coniothyrium sp., and 50,,M CuSO4 was most effective for Phoma sp. A remarkable synergistic effect of tomato juice and RBBR on laccase production was observed for both strains. The upscaling potential of the optimal induction conditions was demonstrated in a lab-scale fermenter which resulted in maximum activities of 11030,±,177,U/L on day,6 for Phoma sp. and 11530,±,161,U/L on day,9 for Coniothyrium sp. This study therefore presents a promising alternative for laccase production in ascomycetes based on a cheap complex substrate in combination with two elicitors. [source]

    Ozonation of 1,3,6-naphthalenetrisulfonic acid in presence of heavy metals

    M Sánchez-Polo
    Abstract A study was conducted of the mechanisms by which heavy metals, commonly present in industrial effluents, increase the purification effectiveness of ozone in the removal of organic contaminants of low biodegradability. For this purpose, the ozonation of 1,3,6-naphthalenetrisulfonic acid (NTS) in the presence of Ni(II), Fe(II), Mn(II), Zn(II), Sr(II), Cr(III), Cd(II), Hg(II), and Cu(II) was examined. The presence of small amounts of Mn(II), Fe(II), Ni(II), Zn(II), and Cr(III) was observed in the system, increasing the degradation rate of the NTS and transforming the dissolved organic matter into CO2. The mineralization of the organic matter was highly favored, especially in the first minutes of treatment. The results obtained appear to indicate that the activity of the metals in the NTS ozonation process is related to their reduction potential. Thus, metals susceptible to oxidation by ozone are potential promoters of NTS ozonation. The presence of Fe(II) or Mn(II) during NTS ozonation increased its degradation rate by 79% and 72% respectively. Moreover, the reaction kinetics of metal oxidation with ozone controls the increase in the purification effectiveness of these systems. The presence of radical scavengers (tert -butanol or bicarbonate) in the medium during the promoted ozonation of NTS showed a negative effect on this process, and the NTS degradation rate decreased with an increasing concentration of these inhibitors in the system. These results confirm that the degradation of NTS by ozone in the presence of heavy metals occurs by a radical mechanism. O3/Zn(II) and O3/Fe(II) systems were applied to the decontamination of urban waste waters. The presence of Zn(II) or Fe(II) during the ozonation produced a reduction during the first 5 min of treatment of 20% or 44%, respectively, in the concentration of dissolved organic matter present in the system. These results show that ozonation in the presence of heavy metals is a highly promising system for the purification of waste waters and industrial effluents. Copyright © 2004 Society of Chemical Industry [source]

    Advanced oxidation processes for destruction of cyanide from thermoelectric power station waste waters

    José M Monteagudo
    Abstract Several advanced oxidation processes for the destruction of cyanide contained in waste waters from thermoelectric power stations of combined-cycle were studied. Thus, oxidation processes involving ozonation at basic pH, ozone/hydrogen peroxide, ozone/ultraviolet radiation and ozone/hydrogen peroxide/ultraviolet radiation have been carried out in a semi-batch reactor. All these methods showed that total cyanide can be successfully degraded but with different reaction rates, and the decrease in the total cyanide concentration can be described by pseudo-first order kinetics. The influence of pH and initial concentration of hydrogen peroxide was studied to find the optimal conditions of the oxidation process. Experimental results of the single ozone treatment indicated that total cyanide is destroyed more rapidly at higher pH (12), while ozonation combined with H2O2 and/or UV is faster at pH 9.5. The optimum concentration of H2O2 was 20.58 × 10,2M because an excess of peroxide decreases the reaction rate, acting as a radical scavenger. The total cyanide degradation rate in the O3/H2O2(20.58 × 10,2M) treatment was the highest among all the combinations studied. However, COD reduction, in the processes using UV radiation such as O3/UV or O3/H2O2/UV was about 75%, while in the processes with H2O2 and/or O3/H2O2 was lower than 57% and was insignificant, when using ozone alone. Copyright © 2003 Society of Chemical Industry [source]

    Kinetics of the degradation by catalytic hydrogenation of tyrosol, a model molecule present in olive oil waste waters

    Dominique Richard
    Abstract Olive mill wastewaters (OMW) constitute an important environmental problem due, among other things, to their high phenolic content. The phytotoxicity of polyphenols makes them resistant to biological treatment. A three-step process comprising adsorption,concentration, catalytic hydrogenation and regeneration on a fixed bed of adsorbent,catalyst was investigated to remove such compounds. Tyrosol (2-(4-hydroxyphenyl)-ethanol) was taken as representative of the polyphenols present in OMW. The catalytic hydrogenation of tyrosol by 30 g kg,1 ruthenium/activated carbon catalyst was carried out in order to establish the reaction mechanism and kinetics necessary for the design of a pilot-scale reactor. Total conversion of tyrosol into non-aromatic compounds was achieved under mild conditions of temperature and pressure. The overall rate of tyrosol removal at 4 MPa and 353 K was . Copyright © 2003 Society of Chemical Industry [source]

    Improved polygalacturonase production from Bacillus sp.

    MG-cp-2 under submerged (SmF), solid state (SSF) fermentation
    Aims:,To investigate the effect of amino acids, vitamins and surfactants on polygalacturonase production from Bacillus sp. MG-cp-2 under submerged (SmF) and solid state fermentation (SSF). Methods and Results:,Bacillus sp. MG-cp-2 was isolated from the outer covering of the seeds of Celastrus paniculatus. Out of the various surfactants, amino acids and vitamins, Tween-60, DL -serine and folic acid maximally enhanced polygalacturonase production by 2·7-fold (240·0 U ml,1), 4·0-fold (360·0 U ml,1) and 3·8-fold (342·0 U ml,1) respectively, under submerged fermentation (SmF). In solid state fermentation (SSF), Tween-80, pyridoxine and DL -ornithine monohydrochloride induced highest enzyme production up to 1·73-fold (6956·5 U g,1), 5·3-fold (21224·4 U g,1) and 5·74-fold (23076·9 U g,1), respectively. Conclusion:,Amino acids and their analogues, vitamins and surfactants effect significantly polygalacturonase production by Bacillus sp. MG-cp-2 when grown under submerged (SmF) and solid state fermentation (SSF) conditions. Significance and Impact of the Study:,The study provides useful information about regulation of polygalacturonase biosynthesis in Bacillus sp. MG-cp-2, which appears to be an interplay of nutritional and physical factors. Alkaline polygalacturonase from Bacillus sp. MG-cp-2 will be extremely useful in the treatment of alkaline pectic waste waters from vegetable and fruit processing industries and in degumming of bast fibres. [source]

    Analysis of carbohydrates and amino acids in vegetable waste waters by ion chromatography

    Michele Arienzo
    Abstract High-performance anion exchange chromatography coupled with pulsed amperometric detection was used for the quantitative determination of total and free sugars in olive oil mill waste waters (OMWW). Automated amino acid ion chromatography was employed to analyse total and free amino acids in the same OMWW. Sugars were analysed in samples pre-purified by means of a three-step purification procedure involving: (i) methanol precipitation of OMWW; (ii) dialysis of the obtained solid and liquid fractions; and (iii) chromatographic purification on RP18 phase followed by Amberlite resin. The amino acids were determined directly in samples obtained from the first two steps performed for sugar analysis. The analysis carried out with the reported methodologies allowed the quantitative determination of total sugars and amino acids and the differentiation between their free and bound forms. The sugars determined were arabinose, fructose, galactose, glucose, rhamnose, xylose, galacturonic and glucuronic acids, and the amino acids were Asp, Glu, Thr, Ser, Pro, Gly, Ala, Val, Met, Ile, Leu, Tyr, Phe, Lys, His, Arg and Cys. Asn, Gln, and Trp were not detected. The technological, biotechnological and environmental advantages arising from this analytical methodology applied to OMWW are briefly discussed. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Low-temperature (9°C) AMD treatment in a sulfidogenic bioreactor dominated by a mesophilic Desulfomicrobium species

    Hannele Auvinen
    Abstract The possibilities for the treatment of low-temperature mine waste waters have not been widely studied. The amenability of low-temperature sulfate reduction for mine waste water treatment at 9°C was studied in a bench-scale fluidized-bed bioreactor (FBR). Formate was used as the electron and carbon source. The first influent for the FBR was acidic, synthetic waste water containing iron, nutrients, and sulfate, followed by diluted barren bioleaching solution (DBBS). The average sulfate reduction rates were 8,mmol,L,1,day,1 and 6,mmol,L,1,day,1 with synthetic waste water and DBBS, respectively. The corresponding specific activities were 2.4 and 1.6,mmol SO,g VSS,1 day,1, respectively. The composition of the microbial community and the active species of the FBR was analyzed by extracting the DNA and RNA, followed by PCR-DGGE with the universal bacterial 16S rRNA gene primers and dsrB -primers specific for sulfate-reducing bacteria. The FBR microbial community was simple and stable and the dominant and active species belonged to the genus Desulfomicrobium. In summary, long-term operation of a low-temperature bioreactor resulted in enrichment of formate-utilizing, psychrotolerant mesophilic sulfate reducing bacteria. Biotechnol. Bioeng. 2009; 104: 740,751 © 2009 Wiley Periodicals, Inc. [source]