Suspension Process | ScienceGate

Obtaining real-time, in situ slurry concentration measurements during unsteady mixing can provide increased understanding into mixer performance. During recent tests an ultrasonic attenuation sensor was inserted into a mixing vessel to measure the slurry concentration during unsteady mixing in real time during pulse jet mixer operation. These pulse jet mixing tests to suspend noncohesive solids in Newtonian liquid were conducted at three geometric scales. To understand the solids suspension process and resulting solids distribution, the concentration of solids in the cloud was measured at various elevations and radial positions during the pulse jet mixer cycle. In the largest scale vessel, concentration profiles were measured at three radial locations: r = 0, 0.5 and 0.9 R where R is the vessel radius. These radial concentration data are being analyzed to provide a model for predicting concentration as a function of elevation. This paper describes pulse jet mixer operation, provides a description of the concentration probe, and presents transient concentration data obtained at three radial positions: in the vessel center (O R), midway between the center and the wall (0.5 R) and near the vessel wall (0.9 R) through out the pulse to provide insight into pulse jet mixer performance.

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Morphologic Modification in ABS by the Incorporation “in Situ” of Nano-ZnO: Study of the Effect on Characteristics and Final Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.644.135 ◽

2010 ◽

Vol 644 ◽

pp. 135-138 ◽

Cited By ~ 2

Author(s):

Ramón Díaz de León ◽

Rebeca Betancourt-Galindo ◽

Bertha A. Puente Urbina ◽

Pablo Acuña ◽

Luís Falcón

Keyword(s):

Acrylonitrile Butadiene Styrene ◽

Total Production ◽

X Ray Diffraction ◽

Nano Zno ◽

Suspension Process ◽

Styrene Acrylonitrile ◽

Poly Acrylonitrile ◽

Period Of Occurrence ◽

Molecular Weight Increase

The synthesis of poly(acrylonitrile-butadiene-styrene) (ABS) was carried out using the mass-suspension process, high cis polybutadiene (PB), benzoyl peroxide (BPO) as the initiator and modified and unmodified nanoparticles of zinc oxide (nano-ZnO). X-ray diffraction (XRD) and Fourier transform infrared (FTIR) were used to characterize the ZnO nanoparticles. A Universal tensiometer, Brokfield viscosimeter and transmission electronic microscopy (TEM) were used to characterize ABS. The employment of nano-ZnO induced an impressive morphologic modification and transformed the highly occluded salame morphology of poly(styrene-acrylonitrile) (SAN) to a highly dispersed one in its matrix. During the reaction, a decrease in the total production of SAN was observed due to the interaction between radicals produced by the initiator and nano-ZnO, causing a molecular weight increase of SAN. The nano-ZnO also induced a decline in the phase inversion and extended the period of occurrence. ABS without nano-ZnO yielded higher mechanical properties than one without any nanoparticles.

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Distribusi Sedimen Permukaan Dasar Laut Perairan Sumba, Nusa Tenggara Timur

Oseanologi dan Limnologi di Indonesia ◽

10.14203/oldi.2017.v2i3.118 ◽

2017 ◽

Vol 2 (3) ◽

pp. 49

Author(s):

Purna Sulastya Putra ◽

Septriono Hari Nugroho

Keyword(s):

Grain Size ◽

Grain Size Analysis ◽

Size Analysis ◽

Sediment Type ◽

Sediment Distribution ◽

Subsurface Sediment ◽

Suspension Process ◽

Subsurface Sediments ◽

The Indian Ocean ◽

Box Corer

<strong>Subsurface sediment distribution in the Sumba Waters, East Nusa Tenggara.</strong> Marine geological survey of the Ekspedisi Widya Nusantara 2016 was conducted in the Sumba Waters on 4 to 26 August 2016 using Baruna Jaya VIII research vessel. The aim of this survey was to reveal the type and characteristics of the subsurface sediments of the Sumba Waters. A total of 13 samples were taken from the different depth in the subsurface bottom of the sea using grabbing methode with box corer. Grain size analysis were conducted using Mastersizer 2000 to understand the characteristics and the sediment type distribution. In general, the type of the subsurface sediment in the Sumba Waters is ranging from medium to very coarse sandy silt. Distribution of the subsurface sediments is correlated to depths. Grain size of the sediments in the Sumba Strait is coarser than in the western and southern of Sumba Island that directly connected to the Indian Ocean. Distribution of the subsurface sediment showing that the sediment, which are distributed further away from the coast is poorly sorted. The deposition of the subsurface-sea sediment is interpreted to represent a calm, and slow sedimentation mechanism under uniform suspension process.

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Mixing system for highly concentrated fine-grained suspensions

Polish Journal of Chemical Technology ◽

10.2478/v10026-009-0043-9 ◽

2009 ◽

Vol 11 (4) ◽

pp. 52-56 ◽

Cited By ~ 2

Author(s):

Jiří Moravec ◽

Tomáš Jirout ◽

František Rieger ◽

Lukáš Krátký

Keyword(s):

Solid Phase ◽

Vessel Diameter ◽

Visual Observation ◽

The State ◽

Geometrical Parameters ◽

Energetic Costs ◽

Fine Grained ◽

Suspension Process ◽

Vessel Bottom ◽

Level Height

Mixing system for highly concentrated fine-grained suspensions The mixing equipment for highly concentrated fine-grained suspensions must be designed differently from the equipment in which a suspension with a low concentration of the solid phase or bigger particles is mixed. It is due to the different rheological properties of the suspensions. In this work we are trying to find a suitable mixing system for a highly concentrated fine-grained suspension. The aim was to determine an effect of particular geometrical parameters of the tested mixing systems on a suspension process, especially from the energetic viewpoint. The energetic costs of all the used mixing systems were compared on the basis of the power consumption which was necessary for reaching the state of sufficient suspension movement in the whole mixed bulk. As a result, it was confirmed that multistage impellers can be used even in standard vessels (with a liquid level height equal to a vessel diameter) with a profit. During experiments, the state of sufficient movement was determined by a visual observation of the suspension at the vessel bottom, at the wall and also at the suspension level.

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APPLICATION OF LES-STOCHASTIC TWO-WAY MODEL TO TWO-PHASE BOUNDARY LAYER FLOWS

Coastal Engineering Proceedings ◽

10.9753/icce.v32.waves.5 ◽

2011 ◽

Vol 1 (32) ◽

pp. 5

Author(s):

Yasunori Watanabe ◽

Yuta Mitobe ◽

Yasuo Niida ◽

Ayumi Saruwatari

Keyword(s):

Boundary Layer ◽

Particle Size ◽

Large Scale ◽

Three Dimensional ◽

Coupling Model ◽

Turbulent Energy ◽

Boundary Layer Flows ◽

Two Phase ◽

Eddy Simulation ◽

Suspension Process

A particle / turbulence two-way coupling model, integrated with conventional stochastic and sub-grid stress models of three-dimensional Large Eddy Simulation (LES), has been applied to the particle-laden turbulent flow in a wave boundary layer developed over seabed with the aim to understand dynamic effects of the particle size and number density to the suspension process in shearing flow over the seabed. While the particle size affects local velocity fluctuations, the particle population significantly induces secondary large-scale flows varying over a scale of the wavelength, and intensifies the turbulent energy near the bed. The particle-induced turbulence may result in additional suspension from the bed, causing a recursive suspension process via the particle turbulence interaction in the boundary layer.

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Groundwater Colloid Properties and their Potential Influence on Radionuclide Transport

MRS Proceedings ◽

10.1557/proc-465-835 ◽

1996 ◽

Vol 465 ◽

Cited By ~ 14

Author(s):

C. Degueldre

Keyword(s):

Steady State ◽

Water Flow Rate ◽

Clay Fraction ◽

Radionuclide Transport ◽

Transport Mechanisms ◽

Transport Models ◽

Contaminated Aquifer ◽

Suspension Process ◽

Alkali Elements ◽

Respective Concentration

ABSTRACTColloid facilitated transport is still an issue in radioactive waste management. Sophisticated phenomenological transport models are available, but progress is required to fully understand mechanisms and parameters. This study lead in this direction. Investigation of the marl groundwater colloids in steady-state conditions at Wellenberg, shows that their concentration is independent of the water flow rate. Their generation is caused by the re-suspension of the rock clay fraction only. The re-suspension process is presently being studied under flow transient conditions. Extension of our measurements to other safety relevant systems as well as a literature survey show that the colloid concentration under steady-state conditions is correlated to the concentration of alkali elements and earth alkali elements. The higher their respective concentration, the fewer colloids are occurring. Considerations on colloid contamination models are also included. The paper emphasises various colloid transport mechanisms including colloid generation from the irreversibly contaminated aquifer.

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