Powder and Bulk Solids Handling Processes

Instrumentation and Control

Koichi Iinoya

• Publisher: CRC Press
• Year: 2017
• Print ISBN:
  9780367451288
• eBook ISBN:
  9781351423250
• Topic: Technology & Engineering
• Subtopic: Chemistry
• Index: Chemistry

Addressing key issues in the instrumentation of powder handling processes, this up-to-date volumeserves as an excellent source of new ideas for designing on-line instruments, as well as a helpfulguide for understanding and applying measurement principles.Describing physical and chemical principles in clear, simple language, Powder and BulkSolids Handling Processes provides substantial background material that lists related industrialfields and the physical representation of powder properties . . . focuses on instrumentation,reviewing state variables in powder processes . . . discusses the sampling of particles from apowder bed or suspension flow as a basic method for evaluating powder handling processes ... andpresents incisive information on various methods and instruments used for on-line measurement ofpowder flow rate, particle concentration in suspension, level of powder in storage vessels, andmore.Complete with references, equations, illustrations, and tables, this volume is essential reading forchemical, mechanical, systems, ceramic, and civil engineers, instrumentation engineers in powderand bulk solid processes, and upper-level undergraduate and graduate students in chemical andmechanical engineering.

1

Introduction to Powder Handling Processes

There are many types of industries where powder is produced by chemical reactions or handled as raw or intermediate materials. Here we give a brief review of various industries relating to powder handling processes. The physical representation of powder properties is then explained as a basis of the process instrumentation. Finally, some examples of powder handling processes are discussed.

1.1 Related Industrial Fields

Powder handling processes play an essential role in the following industries, among others [1]:

Operations in powder handling processes are classified into two categories. One is mechanical, such as size reduction of raw materials, filtration and separation of fine particles, size classification, powder mixing, and granulation. The second, based on heat and mass transfer, includes drying, crystallization, and extraction. Each is called a unit operation. Chemical industries are composed of unit processes for which unit operations are carried out. The several types of mechanical unit operations and their roles in industrial processes are summarized briefly below.

Size reduction: crushing and grinding of solids or particles so as to obtain particles that meet size specifications. The purposes are to make it easy to handle the solid materials in the processes that follow, to make it easy to separate various components contained in the solid, to obtain a higher reaction rate or activity of the solid, to control product quality, and so on.

Gas-solid separation: to recover the particles from gas-solid suspension as a process product or to clarify the process gas. Dust collection in soot and smoke-emitting facilities is an important operation to prevent air pollution.

Filtration: to collect particles from liquid-solid suspension in order to recover the particles as a process product or to clarify the liquid.

Classification: to classify particles according to their properties, such as particle diameter, particle shape, density, electric conductivity, magnetism, and so on. Size classification is one of the most widely used unit operations.

Powder mixing: to distribute more than two types of powder so as to get homogeneous powder of multiple components.

Mulling: to coat the surface of particles uniformly with liquid or paste. Mulling is an operation essential to the plastic treatment of powder.

Granulation: to produce particles of controlled size and shape from powder, liquid suspension, or fused material. Powder handling in subsequent processes becomes easier through granulation. Granulation is also required for the products to fit various applications.

Storing: to store powder in a storage vessel. The purpose is to keep a large amount of powder as feed, intermediate, or final material in industrial processes. Storage vessels work both as the buffer volumes in the processes and as protectors against contamination or change in powder quality.

Transportation: to transp...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright
• Table of Contents
• Preface
• 1 Introduction to Powder Handling Processes
• 2 Introduction to Instrumentation
• 3 Sampling of Particles
• 4 Powder Flow Rate
• 5 Particle Concentration in Suspensions
• 6 Level of Powder in Storage Vessels
• 7 Particle Size
• 8 Moisture Content
• 9 Pressure
• 10 Temperature
• 11 Viscosity of Slurries, Powder Composition, and Motion Sensors
• Index