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Showing 1 to 20 of 100 for “"floc"”.
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Cations and activated sludge floc structure
… For this purpose, cations in solution and in floc were evaluated along with various activated sludge characteristics and the collected waste activated sludge underwent both anaerobic and aerobic digestion. It was found that large amounts of biopolymer (protein + polysaccharide) remained in the …
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The Development of an In-situ Mud Floc Microscope Imaging Device and In-situ Floc Observations from the Lowermost Mississippi River
… can combine to form larger aggregates known as flocs. The size and density, and consequently, the settling velocity, of flocs is highly dynamic and depends on factors such as turbulence levels within the flow and biogeochemical components of the water and sediment. To better predict where mud …
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Chemical and physical properties of acid mine drainage floc
… occurs, a looser gelatinous material called "floc" is produced. The effects of neutralizing chemical, pH, sulfate to iron molar ratio, and solids concentration on floc settling properties were determined in synthetic acid mine drainage. Sulfate was the important factor affecting floc …
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The Effect of Nutritional Conditions on Floc Formation in Zoogloea ramigera.
The formation of bacterial flocs is of crucial importance in the activated sludge process of biological system, treatment waste treatment. In such a generally begins with the settling of large suspended solids from the influent wastewater. The liquid is then channeled into the reaction basin where …
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Seasonal Variation of Mud Floc Sizes in Two Small Freshwater Streams
Flocculation is not only an important part of sediment dynamics within coastal marine waters, but is also a factor of sediment transport within small freshwater streams in Blacksburg, Virginia. The goal of this project was to develop a relationship between floc sizes and stream characteristics …
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The role of floc density measurements in analyzing sludge dewatering characteristics
Floc density measurements may play a significant role in analyzing sludge dewatering characteristics. A laboratory technique was developed to measure this property by means of isopycnic centrifugation. Four laboratory sludges were subjected to a series of dewatering tests: gravity thickening, …
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PARTICLE REMOVAL IN FLOC BLANKET CLARIFIERS VIA INTERNAL FLOW THROUGH POROUS FRACTAL AGGREGATES
… The mechanism of primary particle removal in floc blanket clarifiers was characterized via size-based performance curves obtained from light blocking particle counters that measured the effluent of a laboratory-scale floc blanket clarifier treating synthetic raw water. Particle capture was …
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Application of Polyacrylamide-based Floc Logs for Turbidity Control at Highway Construction Sites
… the use of anionic polyacrylamide (PAM) based Floc Logs, for turbidity control. Five commercially available types of PAM-based Floc Logs were evaluated in jar tests, using soil excavated from Cato Springs Research Center (CSRC, Fayetteville AR) and six types of clay from the Clay Minerals …
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Shear Forces, Floc Structure and their Impact on Anaerobic Digestion and Biosolids Stability
… disintegration are directly related to anaerobic floc structure and its interaction with shearing forces. Mesophilic digestion was studied in two modes of operation, convention high rate and internal recycle mode to enhanced digestion using a wet sludge disintegration device. The internal recycle …
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Floc density measurement and the effects of microproperty variations on sludge dewatering characteristics
… structure: (1) primary particles, (2) floc particles, and (3) aggregate particles. To investigate sludge structure in relation to sludge dewatering, this study has defined sludge structure using several sludge particle micro properties. A laboratory technique incorporating isopycnic …
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Improvements to the Modeling of Average Floc Size in Turbulent Suspensions of Mud
… cohesive mud particles can aggregate, forming flocs whose sizes are a function of hydrodynamic and physiochemical conditions of the suspension. Here we present a new model refining the predicted floc size based on hydrodynamic conditions and inherited floc sizes, as well as on the salinity of …
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Impact of polymer type, dosage, and mixing regime and sludge type on sludge floc properties
… ionic strength on bound water content of sludge flocs. Data determined to evaluate the extent of dewatering included: percent dry solids, bulk density, bound water content (determined by dilatometric method), floc density (determined by isopycnic centrifugation), and cake solids concentrations. …
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High-Intensity Shear as a Wet Sludge Disintegration Technology and a Mechanism for Floc Structure Analysis
… to enhance solublization of solids, though deflocculation and deterioration of dewaterablility was observed. Anaerobic digestibility appears to be enhanced by the addition of a high shear as shown by increases in gas production and volatile solids destruction. The dewatering properties of …
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Elucidating the Response of Activated Sludge Cultures to Toxic Chemicals at the Process, Floc and Metabolic Scales
… consortium structurally organized in bioflocs to treat pollutants present in wastewater. The treatment process efficiency in these systems can be severely affected by toxic chemicals present in the influent wastewater. The effects of chemical toxins at the treatment process level are …
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The effect of certain sludge floc properties on the dewatering characteristics of biological and chemical waste sludges
… sludge viscosity and shear strength, and floc compressibility. The experimental investigation involved the collection of both water and wastewater sludge samples from full-scale treatment plants in the Commonwealth of Virginia. These samples were analyzed for each of the parameters …
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Modelling and control of an activated sludge process using ASM2d and taking into account sludge floc distribution effects
… phosphorous removal, comprehensive sludge floc distribution model remains lacking that would better describe this process. Consequently, the integrated system model has been developed to understand the impact of floc at low DO concentrations, and during the process of biological nitrogen …
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FLOC-SPANNER: An O(1) time, locally self-stabilizing algorithm for geometric spanner construction in a wireless sensor network
Geometric spanners are a popular form of topology control in wireless networks because they yield an efficient, reduced interference subgraph for both unicast and broadcast routing.;In this thesis work a distributed algorithm for creation of geometric spanners in a wireless sensor network is …
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Experiments on the Transformation of Mud Flocs in Turbulent Suspensions
This dissertation aims to better understand how floc aggregate characteristics and behaviors are modified under different local conditions and how such alterations impact the floc settling velocity, which is one of the most crucial parameters influencing sediment transport modeling. A series of …
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Effets des antibiotiques sur le procédé d'épuration par boues activées. Etude du cas de l'érythromycine, du floc bactérien au réacteur biologique
… ont montré qu’en présence d’érythromycine les flocs bactériens se fractionnaient suite aux lyses bactériennes. La microscopie en épifluorescence et la microscopie confocale combinées à des marqueurs de viabilité fluorescents ont permis de déterminer les vitesses de mortalité bactérienne. Ces …
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Cellulase production by fermentation with trichoderma viride on cellulose and wood wastes
… cellulose hydrolysis were studied using Solka Floc cellulose and waste wood (oak) as substrates. The fermentation produced higher enzyme concentration solutions with media containing additional amounts of soy peptone and KH<sub>2</sub>PO<sub>4</sub>.</p> <p>The kinetics of fermentation in …
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