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The activated sludge treatment of pulp and paper wastewater /Peters, Jennifer, 1973- January 1998 (has links)
Biological treatment of pulp and paper wastes by activated sludge is widely practiced in industry to reduce the organic content and toxicity of the wastewater. Most industrial applications require the treatment of a combination of streams from various processes. The composition of the combined stream varies since shock loadings and spills may occur. The objective of this research was to determine the effects of these variations on the microbial community and, ultimately, on the kinetics of the reduction of biological oxygen demand (BOD) and chemical oxygen demand (COD). This will improve the understanding of control requirements for the process. / Effluents from two mills in Quebec were examined. Initially, effluents from a chemithermomechanical pulp (CTMP) mill were used in this research. The objective was to study the effect of six different waste streams mixed with total mill effluent (0--100%) on the reduction of COD and on the microbial population. The remainder of this research focused on treating effluents from a Kraft mill and investigated the effect of hydraulic residence time (HRT) and step inputs of 1%, 2.5% and 5% black liquor on the reduction of COD and BOD5 and on the microbial population. (Abstract shortened by UMI.)
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Examination of PCR parameters for the detection of low numbers of bacteria in potable water : development of a nested PCR protocolJuck, David F. January 1994 (has links)
A simple and sensitive technique was developed for the detection of bacterial cells in a water sample using the nested Polymerase Chain Reaction (nested PCR). The test organism, Escherichia coli, was detectable at an absolute value of 1-5 cells/50 mL of spiked water using ethidium bromide staining and ultraviolet light visualization of PCR product formation on DNA agarose gels. Different parameters of the PCR were examined to determine which ones are the most critical in the design of a detection method for very low numbers of cells in potable water samples. The presence of the filters used for sample concentration in the PCR reaction tube was found to be the most inhibitory component of the procedure and the nested PCR protocol was used to circumvent this inhibitory effect.
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Activated sludge treatment of chemi-thermo-mechanical pulping effluent : a theoretical and experimental investigation of the response to effluent variationDomnik, Corinna S. January 1997 (has links)
Activated sludge has been reported to reduce successfully both organic content and toxicity in effluents originating from chemi-thermo-mechanical pulping (CTMP) mills. The wastewater entering the treatment facility consists of a combination of waste streams derived from various stages of the process. / Activated sludge treatment is sensitive to various operating conditions, including waste stream composition. Changes in operating conditions will affect the treatment process kinetics. The effect of effluent variation was examined using both mathematical modelling and experimental investigation. Mathematical modelling was used to identify the rate parameters having the most significant effect on the system when varied. Experimental studies considered three different CTMP effluents (lean white water, chip wash water and inter-stage wash) and the total mill effluent in order to investigate the actual observed effects of effluent variation. Only the inter-stage wash was found to produce an inhibitory effect, while the other two effluents produced a non-inhibitory effect.
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Deinking recycled paper using column flotationWatson, Jeffrey A., 1971- January 1996 (has links)
The degree of waste paper recycling has been increasing steadily in North America over the last decade. Flotation is a popular method for removing ink from fibres (deinking) and is traditionally performed in mechanical cells. Column flotation has been proposed as an alternative to mechanical cells. In this work, open and packed laboratory and pilot-scale columns were operated to determine their relative merits and how they compare to a circuit of mechanical cells. / It was found that the type of sparger was critical for obtaining high flotation efficiencies. Fine porous stainless steel spargers (0.5 $ mu$m) produced flotation efficiencies which were equal to those of the mechanical cells. Packing was effective in increasing flotation efficiency when the coarse porous stainless steel sparger (100 $ mu$m) was used in the laboratory column and when the variable gap sparger was used in the pilot column. / The organic loss from all column configurations (laboratory and pilot-scale) was less than 3%. / The scale up procedure was evaluated using data from the laboratory column and pilot column dimensions. Finally, using data from the laboratory column, industrial columns were designed.
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In-situ fluidization for remediation of contaminated sandMerchant, Akber. January 2001 (has links)
Experiments were carried out to study the effects of jet velocity and the jet insertion depth on the characteristics of the fluidized region obtained when vertical and inclined water jets were submerged below the surface of saturated sand. Experiments were conducted using sand of mean particle size 507 mum. Water was injected into the sand through a tube of semicircular cross-section (internal diameter 0.55 cm) located at the wall of the tank, forming a half jet. At sufficiently high flowrate a U-shaped fluidized region formed around the jet tube. The fluidized zone was characterized by measuring scour depth, diameter of the fluidized region at the jet insertion depth and diameter of the fluidized region at half the jet insertion depth. For a fixed jet insertion depth, increasing the jet velocity increased the scour depth, the diameter of the fluidized region at the jet insertion depth, and the diameter at half the jet insertion depth. For a fixed jet velocity, the scour depth was independent of the insertion depth, however the two diameters of the fluidized region decreased with increasing jet insertion depth. The profiles obtained for inclined jets were more asymmetric than those for vertical jets. / The effectiveness of the 'up-flow washing' technique for the removal of a water-soluble contaminant (CuSO4) from a saturated bed of sand was investigated for a vertical jet at jet velocities of 213 cm/s and 320 cm/s and jet insertion depths of 5.5 cm and 7.5 cm. Up-flow washing removed the contaminant from the sand bed. The cleaned region extended well beyond the boundary of the fluidized region as jet liquid leaked from the fluidized region and percolated through the fixed bed region. An approximate model for the leakage suggested that 10--20% of the jet liquid leaked from the fluidized region to the fixed bed region.
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The effect of interfacial films on mass transfer of benezene and naphthalene from NAPLs to water /Pasion, Catherine Rodriguez. January 2000 (has links)
The dissolution of aromatic hydrocarbon compounds and polycyclic aromatic hydrocarbons from petroleum phases into water results in groundwater contamination at petroleum contaminated sites. The objective of the research is to investigate whether aging of oil-water interfaces and the formation of interfacial films retard dissolution of solutes from petroleum phases. / The equilibrium partitioning and mass transfer rates of benzene and naphthalene in oil-water systems were evaluated experimentally. The research demonstrated that: (i) the mass transfer of the solutes from Brent Blend crude oil to water is retarded when the oil-water interface is aged; (ii) visually observable interfacial films are formed between gasoline and water when amended with asphaltenes or asphaltenes and resins; (iii) the mass transfer of solutes from gasoline amended with asphaltenes or asphaltenes and resins decreased by a factor of 2.3 to 66 between 4 to 35 days of interface aging and (iv) equilibrium partitioning is not significantly affected by amending the gasoline.
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Analysis of solute mixing at the pore-scale using micromodels and lattice-Boltzmann Finite Volume Modeling /Willingham, Thomas W., January 2006 (has links)
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. / Source: Dissertation Abstracts International, Volume: 68-02, Section: B, page: 1216. Advisers: Charles Werth; Albert Valocchi. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.
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Experimental evaluation of indoor air cleaning technologies and modeling of UV-PCO (photocatalytic oxidation) air cleaners under multiple VOCs conditionsChen, Wenhao. January 2007 (has links)
Thesis (PH.D.) -- Syracuse University, 2007. / "Publication number AAT 3266288"
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Effects of macrolide antimicrobials on anaerobic treatment systems /Shimada Beltran, Toshio. January 2007 (has links)
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-11, Section: B, page: 7585. Advisers: Lutgarde Raskin; Julie L. Zilles; Eberhard Morgenroth. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.
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Deep-layer terrestrial hydrologic memory and mechanisms of its influence on the eco-climatology of the biosphere /Amenu, Geremew Gurmessa. January 2007 (has links)
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-06, Section: B, page: 3647. Adviser: Praveen Kumar. Includes bibliographical references (leaves 332-359) Available on microfilm from Pro Quest Information and Learning.
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