DEM study on the mixed feeding process of coal and cylindroid biomass particles in a screw feeder

The contact force between particles is analysed in this paper. Firstly, theoretical analysis is carried out based on the Hertz–Mindlin (no slip) model. Secondly, the normal force and tangential force are, respectively, simulated in single/double-flight screw feeders with the discharging device at three rotating speeds (60 rpm, 90 rpm, and 120 rpm) using different diameter particles (3 mm, 5 mm, and 7 mm) by the extended distinct element method (EDEM) software. Finally, the simulation results show that the particle diameter has the biggest impact on average contact force in the feeding process. This research provides theoretical basis for the study of the rule of bulk material movement in the screw feeder and the development of the high-precision feeding machine.

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Histopathological and morphological alterations in salivary gland of House fly induced by oral administration Thiamethoxam.

Kurdistan Journal of Applied Research ◽

10.24017/science.2018.1.8 ◽

2018 ◽

Vol 3 (1) ◽

pp. 40-44 ◽

Cited By ~ 1

Author(s):

Karim Mohammed Xider

Keyword(s):

Salivary Gland ◽

Cell Membrane ◽

Oral Administration ◽

Peak Concentration ◽

Active Component ◽

House Fly ◽

Morphological Alterations ◽

Gland Tissue ◽

Gland Duct ◽

Feeding Process

The current work the effect of Actara insecticide belongs to chemical family Neonicotinoid. The active component of thiamethoxam in three concentrations: 0.750 ppm, 1.5 ppm and 2.25ppm on adult house fly salivary glands. Histopathological and morphological effects revealed important alterations produced by this insecticide in histological and morphology of the adult house fly gland tissue categorized by increasing gland duct lumen diameter. These alterations are possibly related with excretion function of salivary gland might be accountable for removing this insecticide. Results show thiamethoxam is a powerful insecticide that performances histologically in salivary glant tissue, triggering alterations in the glands form, cytoplasm with extreme vacuolation ,disruption cell membrane, obvious disorganization tissues cells, terminating in progressive deteriorating phase with changes in nucleus glandular cell's, such alterations occurred together in its size and form of gland, disintegration of nucleus, and presence of apoptosis(fragmentation) nucleus, accelerating the process of glandular degeneration ,and interfering with feeding process of house fly particularly when the peak concentration of insecticide was used.

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Fluidization of mixtures of sand and wood bark biomass particles – an experimental study

10.26678/abcm.encit2016.cit2016-0265 ◽

2016 ◽

Author(s):

Flavia Zinani ◽

Guilherme A Genehr ◽

Flavia Zinani ◽

Maria Luiza Sperb Indrusiak

Keyword(s):

Experimental Study ◽

Wood Bark ◽

Biomass Particles

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Significance of the particle physical properties and the Geldart group in the use of correlations for the prediction of minimum fluidization velocity of biomass–sand binary mixtures

Biomass Conversion and Biorefinery ◽

10.1007/s13399-020-01189-9 ◽

2021 ◽

Author(s):

Louis Edwards Cáceres-Martínez ◽

Diana Carolina Guío-Pérez ◽

Sonia Lucía Rincón-Prat

Keyword(s):

Physical Properties ◽

Binary Mixtures ◽

Minimum Fluidization Velocity ◽

Fluidization Velocity ◽

Minimum Fluidization ◽

Mass Fractions ◽

Char Particle ◽

Geldart Groups ◽

Biomass Particles

AbstractThe present study explores the relevance of the physical properties of biomass particles on the determination of the minimum fluidization velocity (Umf) of binary mixtures. Fluidization experiments were performed in a cold flow unit with diverse biomasses mixed with sand in different mass fractions. Gas velocity and pressure drop across the bed were used to determine Umf. Different correlations reported in the literature were evaluated on their ability to accurately predict Umf of the mixtures. Results showed satisfactory predictions when appropriately identifying correlations according to the corresponding Geldart groups for the biomass particles. This perspective opens new possibilities toward the generalization of correlation factors and helps in improving the accuracy of the prediction for highly heterogeneous mixtures. The methodology also allows the analysis of mixtures for which the experimental approach is difficult, such as those including char particle, with the only requirement of carefully measuring the physical properties of the particles.

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