Effect of Solid Particle Characteristics on Suspension Atomization

Mulhem, Basel; Schulte, Günther

doi:10.1615/atomizspr.v13.i23.100

Cited by 16 publications

(29 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…While there are many specific observations, there are some overall general findings. One group of studies evaluated the role of slurry particle size and generally determined that, if the slurry particles are smaller than the droplets, the slurry particles do not tend to affect the droplet distribution (Mulhem et al 2006(Mulhem et al , 2003(Mulhem et al , 2001Fritsching et al 2009). When the slurry particles become progressively larger and specifically larger than droplets that would be generated in the absence of the slurry particles, droplet formation is naturally influenced.…”

Section: Effect Of Slurry Particlesmentioning

confidence: 99%

Small-Scale Spray Releases: Initial Aerosol Test Results

Mahoney¹,

Gauglitz²,

Kimura³

et al. 2012

View full text Add to dashboard Cite

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex.Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce.To address these technical areas, small-and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. For the combination of both test stands, the round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width × length) 0.3 × 5 to 2.74 × 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the much larger flow rates and equipment that would be required.This report presents the experimental results and analyses for the aerosol measurements obtained in the small-scale test stand. It includes a description of the simulants used and their properties, equipment and operations, data analysis methodologies, and test results. The results of tests investigating the role of slurry particles in plugging small breaches are reported in Mahoney et al. (2012). The results of the...

show abstract

Section: Effect Of Slurry Particlesmentioning

confidence: 99%

Small-Scale Spray Releases: Initial Aerosol Test Results

Mahoney¹,

Gauglitz²,

Kimura³

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Following the improvements in droplet sizes measuring techniques, modern droplet size studies have focussed especially on droplet size correlations for commercial nozzles and droplet size correlations for complex fluid atomisation such as suspensions, slurries and special polymer solutions (Mulhem et al, 2003(Mulhem et al, , 2006Juslin et al, 1995a,b;Yliruusi et al, 1992). Considering the ratio of the energy present in the atomising gas to the surface energy as the main factor determining the droplet sizes, and considering also the liquid loading and the liquid viscosity, Walzel (1993) and Groom et al (2004) derived a semi-empirical droplet size correlation according to Eq.…”

Section: External Mixing Droplet Size Correlationsmentioning

confidence: 99%

“…Following previous authors, some correlations for suspension droplet sizes produced from internal mixing two-fluid nozzles are published in Shirley and Truc (1987), Glaser (1989). Only recently, Mulhem et al (2003Mulhem et al ( , 2006 have published a correlation for suspension droplet sizes generated by an external mixing two-fluid nozzle according to Eq. (51).…”

Section: External Mixing Droplet Size Correlationsmentioning

confidence: 99%

“…(51) has shown good agreement with suspensions containing small particles with diameters in the range of 6--10 m and for d 32 values from 15 to 100 m. Apparently, the atomization process is not significantly affected by the presence of the tested particles in suspension and Eq. (51) has shown adequate precision with pure water droplets (Mulhem et al, 2003). However, Mulhem et al (2006) also showed that as the particles in the suspension increase in size up to the diameter of the liquid droplets, the solid particles and liquid will be more and more separated.…”

Section: External Mixing Droplet Size Correlationsmentioning

confidence: 99%

See 1 more Smart Citation

Two-fluid spray atomisation and pneumatic nozzles for fluid bed coating/agglomeration purposes: A review

Hede¹,

Bach

Jensen

2008

Chemical Engineering Science

186

106

View full text Add to dashboard Cite

“…Für Partikelgrößen d < 50 μm liegt eine monomodale Verteilung vor, die der Vergasung der reinen Suspensionsflüssigkeit entspricht, allerdings sorgen steigende Kapillarkräfte für höhere Suspensionsviskositäten und damit zu größeren Tropfengrößenverteilungen [3].…”

Section: Stand Der Forschungunclassified

Partikelform und Porosität von biogenen Pyrolysekoksen

Nicoleit

Haßel

Niebel

et al. 2015

Chemie Ingenieur Technik

View full text Add to dashboard Cite

Kokspartikel aus pyrolysierter Biomasse variieren stark in Partikelgröße und -form. Die durchschnittliche Länglichkeit der Partikel nimmt mit der Größe signifikant zu. In Abhängigkeit der Partikelgröße ist die durchschnittliche Länglichkeit für die untersuchten Proben unabhängig von Ausgangsstoff und Pyrolyseverfahren. Mit klassischen kugelbasierten Größen-verteilungen werden die Partikel nur ungenau beschrieben. Unter Berücksichtigung der Partikelform lassen sich die Kokse mittels Partikelgrößenverteilungen beschreiben, die auf einem Ellipsoidmodell basieren. Die hohe Schüttgutporosität ist im Wesentlichen auf die interpartikulären Zwischenräume zurückzuführen. Particle Shape and Porosity of Biogenic Pyrolysis CharChar particles from pyrolyzed biomass vary in particle size and shape. On average, the particles are more elongated the larger their size. The average size-specific elongation is almost alike for all investigated samples, i.e. independent from their source material and process. The particle collectives cannot be characterized accurately with classical particle size distributions, which assume spherical particle shape. Accounting for their shape, they can be described more accurately with particle size distributions that are based on an ellipsoid model. The high bulk porosity is mainly attributed to the spaces between particles.

show abstract

Effect of Solid Particle Characteristics on Suspension Atomization

Cited by 16 publications

References 0 publications

Small-Scale Spray Releases: Initial Aerosol Test Results

Small-Scale Spray Releases: Initial Aerosol Test Results

Two-fluid spray atomisation and pneumatic nozzles for fluid bed coating/agglomeration purposes: A review

Partikelform und Porosität von biogenen Pyrolysekoksen

Contact Info

Product

Resources

About