SCEO_L5 - Selected Chemical Engineering Operations Selected...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Selected Chemical Engineering Operations Selected Chemical Engineering Operations LECTURE - 5
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Selected Chemical Engineering Operations Properties and Handling of Particulate Solids • Introduction • Particle shape • Particle size – Mixed particle size and size analysis – Screen analysis – Wet and dry screening – Example • Properties of particulate masses • Storage of solids – Pressure in bins and silos – Flow out of bins • Conveying • Mixing of solids
Background image of page 2
Selected Chemical Engineering Operations Mixing of Solids • The mixing of solids, whether free flowing or cohesive – resembles to some extent the mixing of low viscosity liquids • Both processes intermingle two or more separate components to form a more or less uniform products • More power is normally required in mixing paste and dry solids than in blending liquids • Mixing is harder to define and evaluate with solids and pastes than it is with liquids
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Selected Chemical Engineering Operations Mixing of Solids • A well mixed product is one that does what is required and has the necessary property such as – visual uniformity – high strength – uniform burning rate – other desired characteristic • A good mixer is one that produces this well-mixed product at the lowest overall cost • Mixing heavy pastes, plastic solids, and rubber is more of an art than a science • The properties of the materials to be mixed vary enormously from one process to another
Background image of page 4
Selected Chemical Engineering Operations Mixing of Solids • A batch of solids may be start in mixing process – as a dry free flowing power – become pasty on the addition of liquid – stiff and gummy as a reaction proceeds – then perhaps dry, granular and free flowing once more • Intermediate properties of the material such as – stiffness – tackiness – wettability are as significant in these mixing problems as viscosity and density
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Selected Chemical Engineering Operations Criteria of Mixer Effectiveness: Cohesive Solids • The performance of an industrial mixer is judged by – the time required
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 18

SCEO_L5 - Selected Chemical Engineering Operations Selected...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online