PartTech - Lecture 1

Particulate Materials

__________ (powders or bulk solids) are used widely in all areas of process industries.

Powders or Bulk Solids

Give examples of Particulate Materials (2)

Food Processing

Pharmaceutical

Biotechnology

Oil

Chemical

Mineral Processing

Metallurgical

Detergent

Power Generation

Paint

Plastics

Cosmetics

Give examples of process industries that use particulate materials (12)

Chemical engineers

Chemists

Biologists

Physicists

Pharmacists

Mineral Engineers

Food Technologists

Metallurgists

Examples of professional scientists and engineers that are involved in these industries (read lang)

Material scientists/engineers

Environmental scientists/engineers

Mechanical engineers

Combustion engineers

Civil engineers

More examples of professional scientists and engineers that are involved in these industries (read lang)

2/3

• Figures that indicate the significance of Particle Technology in the world economy

For the DuPont* Company, ~___ of its products involve particulate solids (powders, crystalline solids, granules, flakes, dispersions, paste)

1%

• Figures that indicate the significance of Particle Technology in the world economy

~___% of all electricity generated worldwide is used in reducing particle size.

$ 1 trillion

• Figures that indicate the significance of Particle Technology in the world economy

In 2008, the impact of particulate products to the US economy was estimated to be $__________.

2008

• Figures that indicate the significance of Particle Technology in the world economy

In ___, the impact of particulate products to the US economy was estimated to be $ 1 trillion.

Particle formation processes

Transportation processes

Mixing processes

Drying Processes

Coating Processes

Examples of the processing steps involving particles and powder include (5)

Crystallization

Precipitation

Granulation

Spray Drying

Tabletting

Extrusion

Grinding

Particle FORMATION Processes include (7)

Pneumatic transport

Hydraulic transport

Mechanical conveying

Screw feeding

Particle TRANSPORTATION Processes include (4)

True

True or False

Processes involving particulates require reliable storage facilities and give rise to health and safety issues, which must be satisfactorily handled.

False

Design and operation of many processes across a wide range of industries require knowledge of the behavior of powders and particles.

True or False

Design and operation of many processes across a wide range of industries does not require knowledge of the behavior of powders and particles.

False

Mixing two liquids by stirring, shaking or vibrating is more likely to produce size segregation in a mixture of free-flowing powders of different sizes.

• Design and operation of many processes across a wide range of industries require knowledge of the behavior of powders and particles.

Example 1:

Mixing two liquids by stirring, shaking or vibrating is more likely to produce size segregation in a mixture of free-flowing powders of similar sizes. True or False?

True

• Design and operation of many processes across a wide range of industries require knowledge of the behavior of powders and particles.

Example 2:

A storage hopper may not deliver even 1 kg when the outlet valve is opened unless the hopper has been correctly designed. True or False?

False

When a steel ball is placed at the bottom of a container of sand and the container is vibrated in the vertical plane, the steel ball will rise to the surface.

• Design and operation of many processes across a wide range of industries require knowledge of the behavior of powders and particles.

Example 3:

When a steel ball is placed at the bottom of a container of sand and the container is vibrated in the vertical plane, the steel ball will remain at the bottom. True or False?

Read onleh

• Design and operation of many processes across a wide range of industries require knowledge of the behavior of powders and particles.

Continuation of Example 3:

This steel ball will then sink swiftly to the bottom again if air is passed upwards through the sand causing it to be fluidized.

False

Engineers and scientists are used to dealing with gases and liquids, whose properties can be readily measured, tabulated or even calculated.

True or False

Engineers and scientists are not used to dealing with gases and liquids, whose properties can be readily measured, tabulated or even calculated.

80.1°C

The boiling point of pure benzene at atmospheric pressure can be safely assumed to remain at _____°C.

377 W/m-K

The thermal conductivity of copper can always be relied upon to be _____ W/m-K at 100°C.

100°C.

The thermal conductivity of copper can always be relied upon to be 377 W/m-K at _____°C.

0.001 Pa-s

The viscosity of water at 20°C can be confidently expected to be _____ Pa-s.

Particle size distribution

Particle shape

Surface properties

Humidity of the surrounding atmosphere

State of compaction of powder

Example:

The flow properties of sodium bicarbonate powder depend on (5)

False

These variables are not easy to characterize so their influence on the flow properties of powder are difficult to predict/control.

True or False

The flow properties of sodium bicarbonate powder not only depend on the particle size distribution, but also on particle shape and surface properties, the humidity of the surrounding atmosphere and the state of compaction of the powder.

These variables are easy to characterize so their influence on the flow properties of powder are easy to predict/control.

True

True or False

Powders appear to have some of the behavioral characteristics of the three phases – solids, liquids and gases.

Compressed

Powders can be __________ like gases.

Made to flow

Powders can be __________ like liquids.

Withstand deformation

Powders can __________ like solids.

Particle/Powder Technology

The Science of Particulate Materials is also known as __________.

True

True or False

The importance of the knowledge of the Science of Particulate Materials (a.k.a. Particle/Powder Technology) to the process industries can’t be overemphasized.

True

True or False

Difficulties in the handling/processing powders are often ignored/overlooked at the design stage, such that the powder-related problems are the cause of an inordinate number of production stoppages.

False

The application of even a basic understanding of the ways in which powders behave can minimize the processing problems.

True or False

The application of even a basic understanding of the ways in which powders behave is not enough to minimize the processing problems.

Read onleh

The application of even a basic understanding of the ways in which powders behave can minimize these processing problems, resulting in less downtime, improvements in quality control, and environmental emissions.

1. Characterization

2. Processing

3. Particle Formation

4. Storage and Transport

5. Separation

6. Safety

7. Engineering the Properties of Particulate Systems

Areas of Particle Technology (7)

Size Analysis

• Sub-areas of Particle Technology

1. Characterization (1)

Granulation

Fluidization

• Sub-areas of Particle Technology

2. Processing (2)

Size Enlargement

Size Reduction

• Sub-areas of Particle Technology

3. Particle Formation (2)

Hopper Design

Pneumatic Conveying

Standpipes

Slurry Flow

• Sub-areas of Particle Technology

4. Storage and Transport (4)

Filtration

Settling

Cyclones

• Sub-areas of Particle Technology

5. Separation (3)

Fire and Explosion Hazards

Health Hazards

• Sub-areas of Particle Technology

6. Safety (2)

Colloids

Respirable Drugs

Slurry Rheology

• Sub-areas of Particle Technology

7. Engineering the Properties of Particulate Systems (3)