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Powder / Bulk processes unit operations and key physics concepts

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This index gives access to all the basics knowledge interesting to Process Engineers in the field of powder handling, including powder flow, silo design, mixing principle and technology, milling, solid liquid mixing... when required to go more in detail the pages are referring to the online handbooks by with a collection of pages related to mixing, pneumatic conveying, common equipment, safety etc...

Powder / Bulk processes unit operations and key physics concepts

Powder Mixing introduction

Key dry mixing concept explained, main types of mixers reviewed and reference to mixing handbook

Froude number

Calculation of Froude number, physical interpretation for mixing, usual values

Homogeneity of a powder mix

What is a homogeneous mix, how to measure the homogeneity of a dry mix, the importance of sample size and of sampling, the role and choice of the tracer

Segregation - Demixing

What is segregation, what is promoting demixing, how to avoid it, which mixers to chose

Dosing and weighing

How to properly weight and dose materials in bulk solids handling processes, explainations of key concepts like Gain in Weight GIW and Loss in Weight LIW dosing

Pneumatic conveying - introduction

Overview of pneumatic conveying in bulk handling processes, process advantages, key design criteria, differences in between pressure and vacuum conveying, dilute and dense phase conveying

Solid Gas separation

Overview of solid gas separation methods, filters, cyclones, scrubbers... pros and cons of each methods and key design criteria

Grinding and milling introduction

Overview of grinding and milling processes, main mills design, usage recommendations, pros and cons of each design, key safety aspects of powder milling

Solid liquid suspension

How to properly mix solids and liquids, how to keep solids in suspension in the liquid, general rheology of slurries of solids in liquid

Checking, sieve and magnets

How to protect the process and the product from foreign bodies, sieving, use of powerful magnets, metal detection - general considerations

Magnets for foreign body prevention

Use of powerful magnets to protect the product and the process from metal contaminants, overview of the different designs of magnets, where to position them in the process

Metal detectors for foreign body prevention

Use of metal detectors to protect the product and the process from metal contaminants, where to position them in the process

Sifters for foreign body prevention

Use of sifters to screen the product and the process from contaminants, different sieves designs, where to position them in the process

Powder filling - filling and packing

Powder filling and packing machines, key concepts for filling powders, key points for interface process / filling machine

Dust explosion risks introduction

Safety risks associated with powder process, how to evaluate and handle them


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